Reliable production of biofuels and specifically bioethanol has attracted a significant amount of re-search recently.Within this context,this study deals with dynamic simulation of bioethanol production processes and ...Reliable production of biofuels and specifically bioethanol has attracted a significant amount of re-search recently.Within this context,this study deals with dynamic simulation of bioethanol production processes and in particular aims at developing a mathematical model for describing simultaneous saccharification and co-fermentation （SSCF） of C6 and C5 sugars.The model is constructed by combining existing mathematical mod-els for enzymatic hydrolysis and co-fermentation.An inhibition of ethanol on cellulose conversion is introduced in order to increase the reliability.The mathematical model for the SSCF is verified by comparing the model predic-tions with experimental data obtained from the ethanol production based on kraft paper mill sludge.When fitting the model to the data,only the yield coefficients for glucose and xylose metabolism were fine-tuned,which were found to be 0.43 g·g-1 （ethanol/glucose） and 0.35 g·g-1 （ethanol/xylose） respectively.These promising validation results encourage further model application to evaluate different process configurations for lignocellulosic bioetha-nol technology.展开更多
Co-cultivation of yeast strains with lactic acid bacteria(LAB)can address flavor and nutritional deficiencies in LAB monoculture fermentation.This study aimed to evaluate the strain-specific effects of different yeast...Co-cultivation of yeast strains with lactic acid bacteria(LAB)can address flavor and nutritional deficiencies in LAB monoculture fermentation.This study aimed to evaluate the strain-specific effects of different yeast strains combined with L.plantarum on the bioactive and flavor quality of a multi-substrate beverage containing cherry tomato,apple,goji berry,and broccoli.Five enological yeast strains were paired with L.plantarum HY1,including Torulaspora delbrueckii TD12,Kluyveromyces marxianus KM20,Pichia kluyveri PK7,Hanseniaspora guilliermondii HG2,and Starmerella bacillaris SB2.Results indicated that the co-cultivation enhanced the functional and flavor properties of the fermented beverage compared to LAB monoculture,but the degree was highly strain-dependent.Co-inoculation with P.kluyveri PK7 achieved the highest fermentation rate,LAB population and lactic acid production,which was accompanied by the enrichment of umami and sweet amino acids and the reduction of bitter amino acids.Notably,a striking 6.34-fold increase in sodium cholate adsorption was observed after simulated digestion,suggesting the hypolipidemic effect of P.kluyveri PK7.Additionally,co-fermentation with K.marxianus KM20 significantly increased the levels of vitamin C and phenolic compounds,resulting in the strongest antioxidant capacity.Importantly,the presence of K.marxianus KM20 displayed the highest contents of four novel esters produced by co-fermentation,especially ethyl octanoate and ethyl hexanoate.This study demonstrated that co-culturing LAB with enological P.kluyveri or K.marxianus led to synergistic enhancements of functional and flavor quality in complex plant matrix fermentation,and provided critical insights for developing next-generation fermented fruit-vegetable beverages.展开更多
Developing specialized fermented wines with unique sensory characteristics and defined functional benefits is desirable for the brewing industry.This study investigated the potential of quinoa as a functional adjunct ...Developing specialized fermented wines with unique sensory characteristics and defined functional benefits is desirable for the brewing industry.This study investigated the potential of quinoa as a functional adjunct in Huangjiu brewing.Among yellow,red,and black varieties,red quinoa performed best as a substrate during fermentation,exhibiting robust yeast growth and yielding the highest total flavonoid content(TFC)of 95.08 mg/L,significantly higher than that of rice(13.20 mg/L).Consequently,a rice-red quinoa co-fermentation strategy was established.This synergy substantially enhanced yeast metabolic activity,leading to 5.35-fold and 25.60%increases in flavonoids(73.09 mg/L)and polyphenols(56.20 mg/L),respectively,compared with pure rice fermentation.The optimized brewing matrix enhanced sugar metabolism and increased acetic acid accumulation by 53.20%,reaching 7.43 g/L,resulting in a final fermentation mash with superior antioxidant capacity(ABTS+⋅scavenging activity of 98.40%).Furthermore,red quinoa supplementation increased TFC by 54.50%to 135.32 mg/L and raised total free amino acids(FAA)by 46.86%to 17.77 g/L,with arginine showing the most significant increase,reaching 3.04 g/L,a 3.28-fold increase over the control group.GC-MS analysis showed that red quinoa supplementation increased total esters by 55.97%relative to the control,with a prominent increase in ethyl acetate,and promoted the accumulation of aldehydes such as nonanal.Sensory evaluation showed stronger fruity and grain aromas and higher overall acceptability in quinoa Huangjiu.These findings demonstrate that red quinoa is a potent co-fermenting agent for producing high-quality rice wine with enhanced functional and sensory attributes.展开更多
The commercialization of peanut products is presently limited by the absence of a reliable method of degrading the allergen while yielding acceptable flavor.We examined the effect of co-fermentation of peanut milk by ...The commercialization of peanut products is presently limited by the absence of a reliable method of degrading the allergen while yielding acceptable flavor.We examined the effect of co-fermentation of peanut milk by Lactobacillus plantarum strain P1 and Lactobacillus pentosus strain Y6(FPM-LE)on its protein structure,Ara h 1’s immunoreactivity,physicochemical properties and flavor.Protein analysis showed that protein folding,and degradation occurred during the fermentation and significantly degraded peanut proteins greater than 20 kDa.The immunoreactivity of FPM-LE of Ara h 1 was most reduced by 74.65%compared to sterilized peanut milk.We found that FPM-LE had higher acidity,water holding capacity,viscosity.The flavor of FPM-LE was significantly improved compared to peanut milk fermented by L.plantarum P1 or L.pentosus Y6 alone.The characteristic flavor metabolites(CFM)of FPM-LE were 1-hexanol.Overall,FPM-LE as a product has strong potential to become a hypoallergenic,peanut milk drink with excellent taste and flavor.展开更多
Co-fermentation technology is expected to improve the flavor and quality properties of fermented surimi products.Effects of fermentation with Monascus purpureus(M.purpureus)and Actinomucor elegans(A.elegans)at differe...Co-fermentation technology is expected to improve the flavor and quality properties of fermented surimi products.Effects of fermentation with Monascus purpureus(M.purpureus)and Actinomucor elegans(A.elegans)at different inoculation ratios on the volatile profiles and physicochemical properties of surimi were investigated.Generally,fermentation resulted in significant surimi protein hydrolysis as indicated by increased amino acid nitrogen,TCA-soluble peptide and free amino acid contents,simultaneously accompanied by decreases in hardness,gumminess and chewiness of surimi.Co-fermentation effectively improved the volatile profiles of surimi.Comparatively,a higher inoculation ratio of M.purpureus was favorable for the production of esters and ketones,whereas a higher proportion of A.elegans reduced the aldehyde contents,especially nonanal with fishy odor.Taken together,a 1:1 inoculation ratio of M.purpureus and A.elegans was more conductive to improve the aroma profiles of surimi,with a 77.2%reduction of aldehyde compared to unfermented surimi.展开更多
The global rise in obesity and hyperlipidemia highlights the urgent need for innovative dietary strategies to regulate lipid metabolism.Kombucha,a traditional tea-based fermented beverage,provides health benefits but ...The global rise in obesity and hyperlipidemia highlights the urgent need for innovative dietary strategies to regulate lipid metabolism.Kombucha,a traditional tea-based fermented beverage,provides health benefits but has limited hypolipidemic activity.This study explored lactic acid bacteria(LAB)co-fermentation to enhance its lipid-lowering potential using four strains:Lactiplantibacillus plantarum LP3,Lacticaseibacillus paracasei LCG,Limosilactobacillus fermentum LF1,and Lactobacillus acidophilus AA2.In vitro assays showed a marked improve-ment in hypolipidemic activity,with a 55.2%increase in pancreatic lipase inhibition,and elevated bile salt binding capacities,39.7%for glycocholate and 33.4%for taurocholate.In vivo studies in high-fat diet-fed mice demonstrated significant metabolic improvements,including reduced body weight gain,improved blood lipid profiles,and decreased liver weight.The LCG group showed the highest effects,reducing total cholesterol(TC)by 11.8%,triglyceride(TG)by 18.3%,and increasing high-density lipoprotein cholesterol(HDL-C)by 48.5%.Co-fermentation also enhanced the production of key short-chain fatty acids(SCFAs),including propionic acid,butyric acid,and valeric acid,which are critical for lipid metabolism.Untargeted metabolomics analysis revealed that LAB co-fermentation elevated key hypolipidemic metabolites,such as medium-chain fatty acids,citric acid,flavonoids,and amino acids,which were enriched in pathways like fatty acid oxidation,tricarboxylic acid cycle(TCA)and flavonoid biosynthesis.These findings indicate that LAB co-fermentation enhances kombucha's direct hypolipidemic effects and SCFA-mediated mechanisms,offering a promising route for the development of pre-cision nutrition solutions and sustainable future foods targeting hyperlipidemia and metabolic disorders.展开更多
This study aimed to identify the optimal ratio of Lactiplantibacillus plantarum LP315(LP315)and Streptococcus salivarius subsp.thermophilus S10(S10)and to evaluate the effects of co-fermented milk during storage.The p...This study aimed to identify the optimal ratio of Lactiplantibacillus plantarum LP315(LP315)and Streptococcus salivarius subsp.thermophilus S10(S10)and to evaluate the effects of co-fermented milk during storage.The physicochemical properties of co-fermented milk produced using different LP315:S10 ratios(1:1,1:10,10:1,1:100,and 1:1000)were systematically assessed.Co-fermentation at a 1:1 ratio yielded fermented milk with superior viable counts,acidity,viscosity,water-holding capacity,texture,and sensory attributes after 1 day of storage.Based on this optimal ratio,the physicochemical properties of co-fermented milk were further compared with those of single-strain fermented milks on days 1,7,14,and 21 of storage.The results showed that cofermented milk showed improved physicochemical characteristics compared with single-strain fermented milks,particularly on day 1.Untargeted metabolomics analysis identified 12 key differential metabolites significantly enriched in co-fermented milk and associated with flavor and functionality,including carbohydrates(D-glucose and lacto-N-tetraose),vitamins(pyridoxal and pantothenic acid),organic acids(L-2-hydroxyhexanoic acid,3-(3-hydroxyphenyl)propionic acid,and L-lactic acid),and amino acids(phenylalanine,leucine,proline,glutamic acid,and threonine).These findings highlight LP315 as a promising adjunct strain for use with commercial starters in the production of functional fermented dairy products.展开更多
Spontaneous fermentation imparts unique flavors to beverages,but its uncontrolled nature often leads to quality inconsistencies.Targeted microbial co-fermentation has thus emerged as a key strategy to enhance flavor p...Spontaneous fermentation imparts unique flavors to beverages,but its uncontrolled nature often leads to quality inconsistencies.Targeted microbial co-fermentation has thus emerged as a key strategy to enhance flavor profiles while ensuring production stability.This study investigated the influence of co-fermenting Saccharomyces cer-evisiae with Clostridium butyricum in sugarcane molasses on microbial interactions and rum flavor development.While pure yeast fermentation yielded high ethanol,it produced a low total ester content.In contrast,co-fermentation significantly increased ester levels,which varied with inoculation timing and ratio.Headspace solid-phase microextraction gas chromatography-mass spectrometry(HS-SPME-GC-MS)analysis showed that co-fermentation elevated the concentrations of volatile compounds,particularly esters(increased by 53.7-159.2%)and ketones(increased by 102.7-134.6%).The 24 h sequential inoculation protocol achieved the highest total volatile content(4633.4±113.5μg/L)and ester concentration(2102.13±19.03μg/L).Variable importance in projection(VIP)and odor activity value(OAV)analyses identified 12 key metabolites significantly contributing to fruity and floral aromas.Quantitative descriptive analysis confirmed that sequentially inoculated fermenta-tions exhibited more intense fruity and floral notes,with the 12 h sequential protocol receiving the highest sensory acceptability.In summary,C.butyricum co-fermentation reshaped fermentation kinetics and metabolite distribution,enhancing the diversity and complexity of flavor compounds.This study provides new insights into microbial interactions during rum fermentation and offers theoretical and technical guidance for enhancing the flavor of fermented foods through co-fermentation technology.展开更多
Natto,a nutritious fermented soybean product,is known for its health benefits.Modern production methods use Bacillus subtilis as the starter culture to ensure consistent quality.However,this method overlooks the poten...Natto,a nutritious fermented soybean product,is known for its health benefits.Modern production methods use Bacillus subtilis as the starter culture to ensure consistent quality.However,this method overlooks the potential positive effects of other microbial species present in traditionally,naturally fermented natto.This study explored the effects of ARTP-induced mutants of B.subtilis var.natto and several strains of lactic acid bacteria(LAB)on natto quality.The results showed that these two types of bacteria have complementary roles in fermentation.B.subtilis var.natto,with enhanced extracellular protease activity,promotes the hydrolysis of soy protein and enhances the product’s ACE inhibitory and fibrinolytic activities.Meanwhile,two strains of Lactiplantibacillus plantarum reduced the content of total volatile basic nitrogen(TVB-N)while increasing the content of folic acid in the final product.In addition,B.subtilis var.natto and LAB produce different profiles of volatile compounds(VOCs).Subsequently,B.subtilis var.natto and Lpb.plantarum were used to co-ferment natto in different ratios.The results showed that the two types of bacteria could co-colonize and enhance fermentation quality through their respective strengths.Specifically,Lpb.plantarum strains co-metabolized with B.subtilis var.natto to elevate the content of pyrazines,characteristic VOCs in natto.The optimal quality of natto was achieved when Lpb.plantarum HIS6,Lpb.plantarum LP3 and B.subtilis var.natto Y15-11 were combined in a 2:1:2 ratio.This study not only identified effective combinations of starter cultures with complementary benefits but also elucidated the metabolic pathways of key volatile compounds.Our findings also provide technical insights for improving natto quality,enhancing consumer acceptance,and supporting industrial production.展开更多
Current research on co-fermented fruit wines has primarily focused on flavor profiles,while the theoretical understanding of how co-fermentation affects wine color remains limited.To address this knowledge gap,this st...Current research on co-fermented fruit wines has primarily focused on flavor profiles,while the theoretical understanding of how co-fermentation affects wine color remains limited.To address this knowledge gap,this study systematically optimized fermentation parameters through single-factor experiments examining inoculation methods,inoculation ratios,and fermentation temperatures.The CIELAB parameters and anthocyanin color parameters were determined under optimized conditions.Results demonstrated that the optimal fermentation protocol consisted of LAB inoculation 5 days prior to yeast inoculation,a 1:1 inoculation ratio,and maintenance at 25℃.The co-fermentation process significantly improved mulberry wine color attributes without substantially compromising alcoholic fermentation efficiency.Compared with yeast monoculture,the results of pH differential method showed that co-fermentation increased anthocyanin retention by 30%,and the results of HPLC showed that co-fermentation increased the peak area of C3G by 742.80%.These findings suggest that yeast-LAB co-fermentation provides a promising strategy for quality enhancement in fruit wine production.展开更多
Anaerobic fermentation is an efficient method to extract phosphorus from excess sludge,thereby facilitating its recovery and mitigating the phosphorus resource shortage.However,the prevalent metal-bound phosphorus spe...Anaerobic fermentation is an efficient method to extract phosphorus from excess sludge,thereby facilitating its recovery and mitigating the phosphorus resource shortage.However,the prevalent metal-bound phosphorus species within sludge was difficult to release into the fermentation liquor.To address this,this study evaluated the enhanced phosphorus release performance from sludge containing iron-phosphorus compounds(Fe-P)via co-fermenting it with agriculture wastes.Specifically,protein-rich feather(Feather Group)and polysaccharide-rich tea residue(Tea Group)was respectively dosed into batch-scale fermentation jar.Results showed that the Feather Group exhibited significantly higher levels of released soluble phosphorus(2.1 folds)and volatile fatty acids(41.4 folds)compared to the Control Group,with concentrations reaching up to 280 mg/L and 9366 mg chemical oxygen demand/L,respectively.The activities ofα-glucosidase,neutral protease and acetate kinase in the Feather group were increased by 11.1%,92.3%and 37.6%,respectively,compared with the Control group.Methanogen abundance decreased while hydrolytic acid-producing bacteria and iron-reducing bacteria increased significantly after supplying agricultural wastes.Metagenomic analysis demonstrated a significant increase in genes related to acetic acid synthesis.Mechanism elucidation suggested that increased iron-reducing bacteria abundance promoted Fe3+reduction into Fe2+,thus enhancing phosphorus release from Fe-P compounds.This work may provide valuable information for developing effective strategy to extract phosphorus resource from complex environmental wastes.展开更多
Abstract： Daqu distiller＇s grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The singl...Abstract： Daqu distiller＇s grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The single factor tests were used to investigate the effects of ratio of strains, inoculum size, culture temperature and culture time on the production of microbial oils. The best processing conditions were obtained by orthogonal test through measuring the content of microbial oils in product. The result shows that the microbial oils content of the co-fermented product under the ratio of Trichoderma.koningii to Trichosporon cutaneum of 1：1, the inoculum size of strains of 11% at 28 ℃ for 6 d is 7.15 g/L. It is shown that the production of microbial oils co-fermented by Trichoderma.koningii and Trichosporon cutaneum with Daqu distiller＇s grains is possible. The research provides a new idea for the reuse of Daqu distiller＇s grains and also provides a new way for the development of microbial oils.展开更多
Jujubes,known for their bioactive compounds,are underutilized due to their unappealing dry qualities with lingering bitterness,and short shelf-life when fresh.Co-fermented jujube puree storage could enhance its functi...Jujubes,known for their bioactive compounds,are underutilized due to their unappealing dry qualities with lingering bitterness,and short shelf-life when fresh.Co-fermented jujube puree storage could enhance its functional food potential.For the first time,the impact of storage on 8-day tri-cultured Junzao jujube puree experimented with commercial and indigenous Chinese lactic and acetic acid bacteria on the functionality,physicochemical,volatile compounds,and sensory characteristics was investigated.Despite a decline in microbial loads,the stored purees exhibited excellent viability,with specific tricultures showing promising probiotic activity of more than 6-log CFU/mL of viable counts.Stored purees demonstrated improved acidification,increased total acid content,and reduced pH.Fourier-transform infrared spectroscopic analysis indicated structural changes in polysaccharides,and total flavonoid content quintupled(31.05%),with the highest observed in tri-culture:Lactobacillus casei,Lactobacillus plantarum and Acetobacter pasteurianus(98.74 mg rutin equivalent/100 g)with peculiar formation of l-methionine(1.93 mg/100 g).Antioxidant capacity varied among stored tri-cultured purees,and sensory analysis showed sourness,fruity,floral,thickness,intense yellowish color was associated with the stored tricultures compared to the unfermented sample.Headspace solid-phase microextraction gas chromatography-mass spectrometry analysis identified 80 volatile compounds,with esters(38%)being predominant.Overall,the results demonstrated that lactic-acetic acid tri-culture storage could bio-valorize Junzao jujube puree,improving its organoleptic appeal and shelf-life.展开更多
Microbial fermentation provides an effective strategy to improve the sensory properties of grain foods.This study employed Lentilactobacillus kisonensis(formerly Lactobacillus kisonensis)to ferment quinoa,black barley...Microbial fermentation provides an effective strategy to improve the sensory properties of grain foods.This study employed Lentilactobacillus kisonensis(formerly Lactobacillus kisonensis)to ferment quinoa,black barley,and their mixtures.Volatile organic compounds(VOCs)were analyzed using SPME-GC-MS to characterize their distri-bution profiles,and key aroma compounds were identified based on relative odor activity values(ROAV).Distinct substrate compositions directed different metabolic routes:fermented quinoa was rich in aromatic compounds such as cumene,while black barley was abundant in heterocyclic compounds like 2-pentylfuran.Co-fermentation integrated these divergent profiles,suppressing undesirable VOCs(e.g.,cumene,indole)while optimizing the aromatic hierarchy and reducing flavor intensity of dimethyl trisulfide and dimethyl disulfide,leading to the formation of two distinct aroma profiles:a fruity and grassy notes in the supernatant(dominated byβ-damascenone and nonanal),and a roasted and cereal aromas in the precipitate(dominated by 2-pentylfuran and dimethyl trisulfide).Additionally,the distribution and composition of VOCs differed significantly between the supernatant and precipitate:over 90%of VOCs were retained in the precipitate,with compounds such as phenethyl alcohol,acetoin,and furfural-which impart sweet and caramel aromas-accumulating exclusively in the precipitate.According to pathway analysis,the formation of these VOCs was closely associated with the degradation of carbohydrates and amino acids,lipid oxidation,and the cleavage of carotenoids.Overall,qui-noa-black barley co-fermentation achieved balanced aroma formation through substrate complementation and metabolic synergy,reducing off-flavors while enhancing desirable sensory attributes.展开更多
In recent years,volatile fatty acid(VFA)production through anaerobic fermentation of sewage sludge,instead of methane production,has been regarded as a high-value and promising roadmap for sludge stabilization and res...In recent years,volatile fatty acid(VFA)production through anaerobic fermentation of sewage sludge,instead of methane production,has been regarded as a high-value and promising roadmap for sludge stabilization and resource recovery.This review first presents the effects of some essential factors that influence VFA production and composition.In the second part,we present an extensive analysis of conventional pretreatment and co-fermentation strategies ultimately addressed to improving VFA production and composition.Also,the effectiveness of these approaches is summarized in terms of sludge degradation,hydrolysis rate,and VFA production and composition.According to published studies,it is concluded that some pretreatments such as alkaline and thermal pretreatment are the most effective ways to enhance VFA production from sewage sludge.The possible reasons for the improvement of VFA production by different methods are also discussed.Finally,this review also highlights several current technical challenges and opportunities in VFA production with spectrum control,and further related research is proposed.展开更多
Traditional pile fermentation of Liupao tea relies primarily on endogenous tea constituents as nutrient sources for microbial activity.This study investigated the application of a saccharified Polygonatum solution as ...Traditional pile fermentation of Liupao tea relies primarily on endogenous tea constituents as nutrient sources for microbial activity.This study investigated the application of a saccharified Polygonatum solution as an additional fermentable matrix during pile fermentation in order to examine its association with microbial succession and with the formation of colour-,taste-and flavour-related metabolites.Microbiome profiling revealed that Pol-ygonatum fortification was associated with earlier microbial reorganisation,accompanied by earlier shifts in notable genera such as Staphylococcus and Thermomyces.Under the same piling conditions,the fortified piles showed earlier moderation of bitterness,an earlier transition to a characteristic bright-red infusion,and distinct treatment-related trajectories in volatile compounds.Non-volatile profiling further showed earlier increases in theabrownins and a higher final level in the fortified piles,together with shifts in catechin-derived pigment transformation.Taken together,these results indicate that the introduction of saccharified Polygonatum was associated with coordinated microbial and chemical changes during Liupao tea pile fermentation,providing a useful basis for further investigation of Polygonatum-associated dark-tea fermentation under practical piling conditions.展开更多
The growing focus on sustainable development is encouraging more people to adopt vegetarian diets and alternative protein sources,increasing the demand for natural sources of vitamin B12.Propionibacterium freudenreich...The growing focus on sustainable development is encouraging more people to adopt vegetarian diets and alternative protein sources,increasing the demand for natural sources of vitamin B12.Propionibacterium freudenreichii has been identified as a potent producer of vitamin B12 through fermentation processes.In this study,two distinct batches of beer were produced:one serving as a control comprising probiotic Saccharomyces boulardii CNCM I-745 and Saccharomyces cerevisiae SafAle^(TM) US-05,and the other integrating these yeasts alongside P.freudenreichii DSM 20271.A two-step fermentation approach was adopted,with bacterial fermentation followed by yeast fermentation,to augment the vitamin B12 content in the beer.The application of this methodology resulted in successful enhancement of vitamin B12 levels in the beer,reaching 2.80(±0.3)ng/ml,translating to 1.40(±0.13)μg of vitamin B12 per 500-ml beer bottle.Over the course of an 80-day fermentation period,various parameters including cell counts,sugars,acids,ethanol,volatile compounds and vitamin B12 were monitored.Furthermore,a trained sensory panel was engaged to discern any perceptible differences between the two beer variants.The results suggest that the co-fermented beer exhibited minimal divergence in sensory attributes compared with the yeast-fermented counterpart,implying that the metabolite production by P.freudenreichii did not significantly affect the sensory profile of the beer.This study serves as compelling evidence that the natural fortification of beer with nutritionally significant levels of vitamin B12 can be achieved through fermentation processes involving P.freudenreichii.展开更多
Probiotic stability and activity during broth fermentation are crucial for enhancing the flavour and nutritional value of the final product.This study introduces a novel staining technique that allows differentiation ...Probiotic stability and activity during broth fermentation are crucial for enhancing the flavour and nutritional value of the final product.This study introduces a novel staining technique that allows differentiation of Lacticaseibacillus rhamnosus and Staphylococcus xylosus within sodium alginate(SA)encapsulated microspheres without altering the SA structure.Encapsulation efficiencies were 88.41%for L.rhamnosus and 82.68%for S.xylosus,with the staining technique enhancing thermal stability.Co-fermentation in pork broth resulted in significant increases in organic acids(e.g.,lactic acid from 3.209 g/L to 8.673 g/L and acetic acid),thereby improving sensory attributes.Amino acid analysis revealed substantial increases in essential amino acids,including glutamic acid(from 7.493 mg/100 g to 27.422 mg/100 g)and glycine(from 12.435 mg/100 g to 30.632 mg/100 g),which contributed to an improved nutritional profile.Furthermore,significant increases in volatile compounds,such as isophorone(up to 148.25μg/L),1-Octanol(up to 39.02μg/L),and benzaldehyde(up to 570.84μg/L),enriched the aroma of the pork broth.SA encapsulation maintained probiotic viability throughout the extended fermentation period,while strain interactions further enriched both nutritional and flavour profiles.These findings highlight the potential of SA encapsulation combined with co-fermentation to optimize the sensory and nutritional qualities of fermented foods.展开更多
Kazak cheese is a traditional acid-curd dairy product in China,valued for its unique flavor but limited by inconsistent quality in industrial production.Its flavor profile is primarily determined by lactic acid bacter...Kazak cheese is a traditional acid-curd dairy product in China,valued for its unique flavor but limited by inconsistent quality in industrial production.Its flavor profile is primarily determined by lactic acid bacteria(LAB)during fermentation,however,their strain-specific characteristics affect the profiles of volatile com-pounds.This study evaluated the effect of the Lactobacillus casei TCS,Pediococcus pentosaceus 4D,Lactobacillus casei TGA and Lactococcus lactis 408 on the volatile compounds of Kazak cheeses.Using GC-IMS analysis,58 volatile compounds were identified,predominantly acids and ketones,which constituted 75%of the total volatile compounds.Based on ROAV results,acetaldehyde(13.12%-22.20%),acetoin(6.95%-10.06%)significantly contributed to the cheese flavor.Principal component analysis demonstrated that 3-methylbutanal(nutty notes)was correlated with L.lactis 408-fermented Kazak cheese,while diacetyl(milky notes)was asso-ciated with L.casei TGA-fermented cheeses.Furthermore,co-fermentation of L.lactis 408 and L.casei TCS significantly increased acetoin concentration(1406 mg/kg,p<0.01)in Kazak cheese.Additionally,molecular docking analysis revealed that acetoin exhibited higher binding energy with acetoin reductase than that with diacetyl and diacetyl reductase,thereby facilitating the production of 2,3-butanediol.These findings highlight the pivotal roles of microbial metabolism in Kazak cheese flavor and provide insights into optimizing the flavor compositions.展开更多
Lactic acid bacteria(LAB)fermentation has the potential to be an effective way to improve the flavor of foods.In this study,Lactococcus lactis(L.lactis),Lactobacillus plantarum(L.plantarum)and Lactobacillus rhamnosus(...Lactic acid bacteria(LAB)fermentation has the potential to be an effective way to improve the flavor of foods.In this study,Lactococcus lactis(L.lactis),Lactobacillus plantarum(L.plantarum)and Lactobacillus rhamnosus(L.rhamnosus)co-fermented oat beverage was prepared and both the molecular and biochemical basis for its unique flavor formation were investigated by using cross-correlation analysis combined with untargeted flavoromics.Results showed that via co-fermentation main flavor substances like organic acids,free amino acids(FAAs)and volatile flavor compounds(VFCs)could be regulated dynamically.Interaction network analysis and redundancy analysis(RDA)convinced the crucial roles of three bacteria in shaping the overall flavor profile of co-fermented beverage,especially for the formation of soft sourness,sweetness,and freshness.According to untargeted metabolomics,it could be concluded that co-fermentation regulated significant differential metabolites(56 in total)unique to LAB co-fermented oat beverage such as benzoic acid,DL-arginine,uridine,and citrate.KEGG pathway enrichment analysis further predicted the viable formation pathways of key flavor compounds obtained by RDA such as organic acids(malate,citrate,et al.),FAAs(aspartate,glutamate,et al.)and VFCs(2,3-butanedione,1-nonanol,et al.).This work demonstrates the positive flavor contribution of LAB co-fermentation,providing valuable reference for subsequent multi-omics studies on fermented oat products.展开更多
基金Supported by the Mexican National Council for Science and Technology (CONACyT# 118903)the Danish Research Council for Technology and Production Sciences (FTP# 274-07-0339)
文摘Reliable production of biofuels and specifically bioethanol has attracted a significant amount of re-search recently.Within this context,this study deals with dynamic simulation of bioethanol production processes and in particular aims at developing a mathematical model for describing simultaneous saccharification and co-fermentation （SSCF） of C6 and C5 sugars.The model is constructed by combining existing mathematical mod-els for enzymatic hydrolysis and co-fermentation.An inhibition of ethanol on cellulose conversion is introduced in order to increase the reliability.The mathematical model for the SSCF is verified by comparing the model predic-tions with experimental data obtained from the ethanol production based on kraft paper mill sludge.When fitting the model to the data,only the yield coefficients for glucose and xylose metabolism were fine-tuned,which were found to be 0.43 g·g-1 （ethanol/glucose） and 0.35 g·g-1 （ethanol/xylose） respectively.These promising validation results encourage further model application to evaluate different process configurations for lignocellulosic bioetha-nol technology.
基金supported financially by China Agriculture Research System(CARS-29).
文摘Co-cultivation of yeast strains with lactic acid bacteria(LAB)can address flavor and nutritional deficiencies in LAB monoculture fermentation.This study aimed to evaluate the strain-specific effects of different yeast strains combined with L.plantarum on the bioactive and flavor quality of a multi-substrate beverage containing cherry tomato,apple,goji berry,and broccoli.Five enological yeast strains were paired with L.plantarum HY1,including Torulaspora delbrueckii TD12,Kluyveromyces marxianus KM20,Pichia kluyveri PK7,Hanseniaspora guilliermondii HG2,and Starmerella bacillaris SB2.Results indicated that the co-cultivation enhanced the functional and flavor properties of the fermented beverage compared to LAB monoculture,but the degree was highly strain-dependent.Co-inoculation with P.kluyveri PK7 achieved the highest fermentation rate,LAB population and lactic acid production,which was accompanied by the enrichment of umami and sweet amino acids and the reduction of bitter amino acids.Notably,a striking 6.34-fold increase in sodium cholate adsorption was observed after simulated digestion,suggesting the hypolipidemic effect of P.kluyveri PK7.Additionally,co-fermentation with K.marxianus KM20 significantly increased the levels of vitamin C and phenolic compounds,resulting in the strongest antioxidant capacity.Importantly,the presence of K.marxianus KM20 displayed the highest contents of four novel esters produced by co-fermentation,especially ethyl octanoate and ethyl hexanoate.This study demonstrated that co-culturing LAB with enological P.kluyveri or K.marxianus led to synergistic enhancements of functional and flavor quality in complex plant matrix fermentation,and provided critical insights for developing next-generation fermented fruit-vegetable beverages.
基金National Natural Science Foundation of China(U23A20259 and 32372307)the Shanghai Oriental Talent Leading Project(T2024105)+1 种基金the Young Elite Scientist Sponsorship Program of China Association for Science and Technology(YESS20220128),Shanghai Rising-Star Pro-gram(24QA2706000)the Shanghai Research Center for Food Microbiology Engineering(19DZ2281100).
文摘Developing specialized fermented wines with unique sensory characteristics and defined functional benefits is desirable for the brewing industry.This study investigated the potential of quinoa as a functional adjunct in Huangjiu brewing.Among yellow,red,and black varieties,red quinoa performed best as a substrate during fermentation,exhibiting robust yeast growth and yielding the highest total flavonoid content(TFC)of 95.08 mg/L,significantly higher than that of rice(13.20 mg/L).Consequently,a rice-red quinoa co-fermentation strategy was established.This synergy substantially enhanced yeast metabolic activity,leading to 5.35-fold and 25.60%increases in flavonoids(73.09 mg/L)and polyphenols(56.20 mg/L),respectively,compared with pure rice fermentation.The optimized brewing matrix enhanced sugar metabolism and increased acetic acid accumulation by 53.20%,reaching 7.43 g/L,resulting in a final fermentation mash with superior antioxidant capacity(ABTS+⋅scavenging activity of 98.40%).Furthermore,red quinoa supplementation increased TFC by 54.50%to 135.32 mg/L and raised total free amino acids(FAA)by 46.86%to 17.77 g/L,with arginine showing the most significant increase,reaching 3.04 g/L,a 3.28-fold increase over the control group.GC-MS analysis showed that red quinoa supplementation increased total esters by 55.97%relative to the control,with a prominent increase in ethyl acetate,and promoted the accumulation of aldehydes such as nonanal.Sensory evaluation showed stronger fruity and grain aromas and higher overall acceptability in quinoa Huangjiu.These findings demonstrate that red quinoa is a potent co-fermenting agent for producing high-quality rice wine with enhanced functional and sensory attributes.
基金supported by National Natural Science Foundation of China(NSFC,Project N0.32201999)Key R&D Plan of Jiangxi Province(20232BBF60024)+2 种基金National Key Laboratory Project(20232BCD44005)Agricultural key core technology research project of Jiangxi Province(JXNK202303-05)Central Government Guide Local Special Fund Project for Scientific and Technological Development of Jiangxi Prov-ince(20221ZDD02001).
文摘The commercialization of peanut products is presently limited by the absence of a reliable method of degrading the allergen while yielding acceptable flavor.We examined the effect of co-fermentation of peanut milk by Lactobacillus plantarum strain P1 and Lactobacillus pentosus strain Y6(FPM-LE)on its protein structure,Ara h 1’s immunoreactivity,physicochemical properties and flavor.Protein analysis showed that protein folding,and degradation occurred during the fermentation and significantly degraded peanut proteins greater than 20 kDa.The immunoreactivity of FPM-LE of Ara h 1 was most reduced by 74.65%compared to sterilized peanut milk.We found that FPM-LE had higher acidity,water holding capacity,viscosity.The flavor of FPM-LE was significantly improved compared to peanut milk fermented by L.plantarum P1 or L.pentosus Y6 alone.The characteristic flavor metabolites(CFM)of FPM-LE were 1-hexanol.Overall,FPM-LE as a product has strong potential to become a hypoallergenic,peanut milk drink with excellent taste and flavor.
基金supported by the National Key R&D Program of China(2023YFD2401502)National Natural Science Foundation of China(No.32402151).
文摘Co-fermentation technology is expected to improve the flavor and quality properties of fermented surimi products.Effects of fermentation with Monascus purpureus(M.purpureus)and Actinomucor elegans(A.elegans)at different inoculation ratios on the volatile profiles and physicochemical properties of surimi were investigated.Generally,fermentation resulted in significant surimi protein hydrolysis as indicated by increased amino acid nitrogen,TCA-soluble peptide and free amino acid contents,simultaneously accompanied by decreases in hardness,gumminess and chewiness of surimi.Co-fermentation effectively improved the volatile profiles of surimi.Comparatively,a higher inoculation ratio of M.purpureus was favorable for the production of esters and ketones,whereas a higher proportion of A.elegans reduced the aldehyde contents,especially nonanal with fishy odor.Taken together,a 1:1 inoculation ratio of M.purpureus and A.elegans was more conductive to improve the aroma profiles of surimi,with a 77.2%reduction of aldehyde compared to unfermented surimi.
基金support from the National Natural Science Foundation of China(Grants No.32302267,32302953)China Postdoctoral Science Foundation(Grants No.2021TQ0274,2022M720120)“QingLan”Talent Support Program of Yangzhou University.
文摘The global rise in obesity and hyperlipidemia highlights the urgent need for innovative dietary strategies to regulate lipid metabolism.Kombucha,a traditional tea-based fermented beverage,provides health benefits but has limited hypolipidemic activity.This study explored lactic acid bacteria(LAB)co-fermentation to enhance its lipid-lowering potential using four strains:Lactiplantibacillus plantarum LP3,Lacticaseibacillus paracasei LCG,Limosilactobacillus fermentum LF1,and Lactobacillus acidophilus AA2.In vitro assays showed a marked improve-ment in hypolipidemic activity,with a 55.2%increase in pancreatic lipase inhibition,and elevated bile salt binding capacities,39.7%for glycocholate and 33.4%for taurocholate.In vivo studies in high-fat diet-fed mice demonstrated significant metabolic improvements,including reduced body weight gain,improved blood lipid profiles,and decreased liver weight.The LCG group showed the highest effects,reducing total cholesterol(TC)by 11.8%,triglyceride(TG)by 18.3%,and increasing high-density lipoprotein cholesterol(HDL-C)by 48.5%.Co-fermentation also enhanced the production of key short-chain fatty acids(SCFAs),including propionic acid,butyric acid,and valeric acid,which are critical for lipid metabolism.Untargeted metabolomics analysis revealed that LAB co-fermentation elevated key hypolipidemic metabolites,such as medium-chain fatty acids,citric acid,flavonoids,and amino acids,which were enriched in pathways like fatty acid oxidation,tricarboxylic acid cycle(TCA)and flavonoid biosynthesis.These findings indicate that LAB co-fermentation enhances kombucha's direct hypolipidemic effects and SCFA-mediated mechanisms,offering a promising route for the development of pre-cision nutrition solutions and sustainable future foods targeting hyperlipidemia and metabolic disorders.
基金funded by Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(NJYT25017)Inner Mongolia Autonomous Region Natural Science Foundation(2024LHMS03043).
文摘This study aimed to identify the optimal ratio of Lactiplantibacillus plantarum LP315(LP315)and Streptococcus salivarius subsp.thermophilus S10(S10)and to evaluate the effects of co-fermented milk during storage.The physicochemical properties of co-fermented milk produced using different LP315:S10 ratios(1:1,1:10,10:1,1:100,and 1:1000)were systematically assessed.Co-fermentation at a 1:1 ratio yielded fermented milk with superior viable counts,acidity,viscosity,water-holding capacity,texture,and sensory attributes after 1 day of storage.Based on this optimal ratio,the physicochemical properties of co-fermented milk were further compared with those of single-strain fermented milks on days 1,7,14,and 21 of storage.The results showed that cofermented milk showed improved physicochemical characteristics compared with single-strain fermented milks,particularly on day 1.Untargeted metabolomics analysis identified 12 key differential metabolites significantly enriched in co-fermented milk and associated with flavor and functionality,including carbohydrates(D-glucose and lacto-N-tetraose),vitamins(pyridoxal and pantothenic acid),organic acids(L-2-hydroxyhexanoic acid,3-(3-hydroxyphenyl)propionic acid,and L-lactic acid),and amino acids(phenylalanine,leucine,proline,glutamic acid,and threonine).These findings highlight LP315 as a promising adjunct strain for use with commercial starters in the production of functional fermented dairy products.
基金supported by grant from the Basic Research Program of Jiangsu(BK20252085,BK20251603)the National Natural Science Foundation of China(32302030).
文摘Spontaneous fermentation imparts unique flavors to beverages,but its uncontrolled nature often leads to quality inconsistencies.Targeted microbial co-fermentation has thus emerged as a key strategy to enhance flavor profiles while ensuring production stability.This study investigated the influence of co-fermenting Saccharomyces cer-evisiae with Clostridium butyricum in sugarcane molasses on microbial interactions and rum flavor development.While pure yeast fermentation yielded high ethanol,it produced a low total ester content.In contrast,co-fermentation significantly increased ester levels,which varied with inoculation timing and ratio.Headspace solid-phase microextraction gas chromatography-mass spectrometry(HS-SPME-GC-MS)analysis showed that co-fermentation elevated the concentrations of volatile compounds,particularly esters(increased by 53.7-159.2%)and ketones(increased by 102.7-134.6%).The 24 h sequential inoculation protocol achieved the highest total volatile content(4633.4±113.5μg/L)and ester concentration(2102.13±19.03μg/L).Variable importance in projection(VIP)and odor activity value(OAV)analyses identified 12 key metabolites significantly contributing to fruity and floral aromas.Quantitative descriptive analysis confirmed that sequentially inoculated fermenta-tions exhibited more intense fruity and floral notes,with the 12 h sequential protocol receiving the highest sensory acceptability.In summary,C.butyricum co-fermentation reshaped fermentation kinetics and metabolite distribution,enhancing the diversity and complexity of flavor compounds.This study provides new insights into microbial interactions during rum fermentation and offers theoretical and technical guidance for enhancing the flavor of fermented foods through co-fermentation technology.
基金supported by the National Key Research and Development Project of China(2022YFD2100905)the National Natural Science Foundation of China(grant number 32072289).
文摘Natto,a nutritious fermented soybean product,is known for its health benefits.Modern production methods use Bacillus subtilis as the starter culture to ensure consistent quality.However,this method overlooks the potential positive effects of other microbial species present in traditionally,naturally fermented natto.This study explored the effects of ARTP-induced mutants of B.subtilis var.natto and several strains of lactic acid bacteria(LAB)on natto quality.The results showed that these two types of bacteria have complementary roles in fermentation.B.subtilis var.natto,with enhanced extracellular protease activity,promotes the hydrolysis of soy protein and enhances the product’s ACE inhibitory and fibrinolytic activities.Meanwhile,two strains of Lactiplantibacillus plantarum reduced the content of total volatile basic nitrogen(TVB-N)while increasing the content of folic acid in the final product.In addition,B.subtilis var.natto and LAB produce different profiles of volatile compounds(VOCs).Subsequently,B.subtilis var.natto and Lpb.plantarum were used to co-ferment natto in different ratios.The results showed that the two types of bacteria could co-colonize and enhance fermentation quality through their respective strengths.Specifically,Lpb.plantarum strains co-metabolized with B.subtilis var.natto to elevate the content of pyrazines,characteristic VOCs in natto.The optimal quality of natto was achieved when Lpb.plantarum HIS6,Lpb.plantarum LP3 and B.subtilis var.natto Y15-11 were combined in a 2:1:2 ratio.This study not only identified effective combinations of starter cultures with complementary benefits but also elucidated the metabolic pathways of key volatile compounds.Our findings also provide technical insights for improving natto quality,enhancing consumer acceptance,and supporting industrial production.
基金supported by the National Natural Science Foundation of China(No.32572601)the Technology Program of Guangzhou(No.2024B03J1360)+1 种基金the National Key Research and Development Program(NO.2024YFD2101300)the Guangzhou Key Research and Development Program(NO.2025B03J0008)。
文摘Current research on co-fermented fruit wines has primarily focused on flavor profiles,while the theoretical understanding of how co-fermentation affects wine color remains limited.To address this knowledge gap,this study systematically optimized fermentation parameters through single-factor experiments examining inoculation methods,inoculation ratios,and fermentation temperatures.The CIELAB parameters and anthocyanin color parameters were determined under optimized conditions.Results demonstrated that the optimal fermentation protocol consisted of LAB inoculation 5 days prior to yeast inoculation,a 1:1 inoculation ratio,and maintenance at 25℃.The co-fermentation process significantly improved mulberry wine color attributes without substantially compromising alcoholic fermentation efficiency.Compared with yeast monoculture,the results of pH differential method showed that co-fermentation increased anthocyanin retention by 30%,and the results of HPLC showed that co-fermentation increased the peak area of C3G by 742.80%.These findings suggest that yeast-LAB co-fermentation provides a promising strategy for quality enhancement in fruit wine production.
基金supported by the“Pioneer”and“Leading Goose”R&D Program of Zhejiang(No.2023C03149).
文摘Anaerobic fermentation is an efficient method to extract phosphorus from excess sludge,thereby facilitating its recovery and mitigating the phosphorus resource shortage.However,the prevalent metal-bound phosphorus species within sludge was difficult to release into the fermentation liquor.To address this,this study evaluated the enhanced phosphorus release performance from sludge containing iron-phosphorus compounds(Fe-P)via co-fermenting it with agriculture wastes.Specifically,protein-rich feather(Feather Group)and polysaccharide-rich tea residue(Tea Group)was respectively dosed into batch-scale fermentation jar.Results showed that the Feather Group exhibited significantly higher levels of released soluble phosphorus(2.1 folds)and volatile fatty acids(41.4 folds)compared to the Control Group,with concentrations reaching up to 280 mg/L and 9366 mg chemical oxygen demand/L,respectively.The activities ofα-glucosidase,neutral protease and acetate kinase in the Feather group were increased by 11.1%,92.3%and 37.6%,respectively,compared with the Control group.Methanogen abundance decreased while hydrolytic acid-producing bacteria and iron-reducing bacteria increased significantly after supplying agricultural wastes.Metagenomic analysis demonstrated a significant increase in genes related to acetic acid synthesis.Mechanism elucidation suggested that increased iron-reducing bacteria abundance promoted Fe3+reduction into Fe2+,thus enhancing phosphorus release from Fe-P compounds.This work may provide valuable information for developing effective strategy to extract phosphorus resource from complex environmental wastes.
基金Project(10A110) supported by Hunan Provincial Education Department of ChinaProject(2010JT4055) supported by Hunan Provincial Science & Technology Department of China
文摘Abstract： Daqu distiller＇s grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The single factor tests were used to investigate the effects of ratio of strains, inoculum size, culture temperature and culture time on the production of microbial oils. The best processing conditions were obtained by orthogonal test through measuring the content of microbial oils in product. The result shows that the microbial oils content of the co-fermented product under the ratio of Trichoderma.koningii to Trichosporon cutaneum of 1：1, the inoculum size of strains of 11% at 28 ℃ for 6 d is 7.15 g/L. It is shown that the production of microbial oils co-fermented by Trichoderma.koningii and Trichosporon cutaneum with Daqu distiller＇s grains is possible. The research provides a new idea for the reuse of Daqu distiller＇s grains and also provides a new way for the development of microbial oils.
基金grateful to the management of Zhenjiang Key Research and Development Program(Modern Agriculture)for their support[grant number NY2020020].
文摘Jujubes,known for their bioactive compounds,are underutilized due to their unappealing dry qualities with lingering bitterness,and short shelf-life when fresh.Co-fermented jujube puree storage could enhance its functional food potential.For the first time,the impact of storage on 8-day tri-cultured Junzao jujube puree experimented with commercial and indigenous Chinese lactic and acetic acid bacteria on the functionality,physicochemical,volatile compounds,and sensory characteristics was investigated.Despite a decline in microbial loads,the stored purees exhibited excellent viability,with specific tricultures showing promising probiotic activity of more than 6-log CFU/mL of viable counts.Stored purees demonstrated improved acidification,increased total acid content,and reduced pH.Fourier-transform infrared spectroscopic analysis indicated structural changes in polysaccharides,and total flavonoid content quintupled(31.05%),with the highest observed in tri-culture:Lactobacillus casei,Lactobacillus plantarum and Acetobacter pasteurianus(98.74 mg rutin equivalent/100 g)with peculiar formation of l-methionine(1.93 mg/100 g).Antioxidant capacity varied among stored tri-cultured purees,and sensory analysis showed sourness,fruity,floral,thickness,intense yellowish color was associated with the stored tricultures compared to the unfermented sample.Headspace solid-phase microextraction gas chromatography-mass spectrometry analysis identified 80 volatile compounds,with esters(38%)being predominant.Overall,the results demonstrated that lactic-acetic acid tri-culture storage could bio-valorize Junzao jujube puree,improving its organoleptic appeal and shelf-life.
基金supported by grants from the National Natural Science Foundation of China(Grant No.32172221).
文摘Microbial fermentation provides an effective strategy to improve the sensory properties of grain foods.This study employed Lentilactobacillus kisonensis(formerly Lactobacillus kisonensis)to ferment quinoa,black barley,and their mixtures.Volatile organic compounds(VOCs)were analyzed using SPME-GC-MS to characterize their distri-bution profiles,and key aroma compounds were identified based on relative odor activity values(ROAV).Distinct substrate compositions directed different metabolic routes:fermented quinoa was rich in aromatic compounds such as cumene,while black barley was abundant in heterocyclic compounds like 2-pentylfuran.Co-fermentation integrated these divergent profiles,suppressing undesirable VOCs(e.g.,cumene,indole)while optimizing the aromatic hierarchy and reducing flavor intensity of dimethyl trisulfide and dimethyl disulfide,leading to the formation of two distinct aroma profiles:a fruity and grassy notes in the supernatant(dominated byβ-damascenone and nonanal),and a roasted and cereal aromas in the precipitate(dominated by 2-pentylfuran and dimethyl trisulfide).Additionally,the distribution and composition of VOCs differed significantly between the supernatant and precipitate:over 90%of VOCs were retained in the precipitate,with compounds such as phenethyl alcohol,acetoin,and furfural-which impart sweet and caramel aromas-accumulating exclusively in the precipitate.According to pathway analysis,the formation of these VOCs was closely associated with the degradation of carbohydrates and amino acids,lipid oxidation,and the cleavage of carotenoids.Overall,qui-noa-black barley co-fermentation achieved balanced aroma formation through substrate complementation and metabolic synergy,reducing off-flavors while enhancing desirable sensory attributes.
基金supported by the National Natural Science Foundation of China(No.51578068)"One Thousand Talent Plan" Youth Program
文摘In recent years,volatile fatty acid(VFA)production through anaerobic fermentation of sewage sludge,instead of methane production,has been regarded as a high-value and promising roadmap for sludge stabilization and resource recovery.This review first presents the effects of some essential factors that influence VFA production and composition.In the second part,we present an extensive analysis of conventional pretreatment and co-fermentation strategies ultimately addressed to improving VFA production and composition.Also,the effectiveness of these approaches is summarized in terms of sludge degradation,hydrolysis rate,and VFA production and composition.According to published studies,it is concluded that some pretreatments such as alkaline and thermal pretreatment are the most effective ways to enhance VFA production from sewage sludge.The possible reasons for the improvement of VFA production by different methods are also discussed.Finally,this review also highlights several current technical challenges and opportunities in VFA production with spectrum control,and further related research is proposed.
基金supported by the Guangxi Science and Technology Program(Grant No.AB24010194)the Special Project for Research and Development in Key areas of Guangdong Province(Grant No.2022B0202050001)the project of China Agriculture Research System of MOF and MARA(CARS-21).
文摘Traditional pile fermentation of Liupao tea relies primarily on endogenous tea constituents as nutrient sources for microbial activity.This study investigated the application of a saccharified Polygonatum solution as an additional fermentable matrix during pile fermentation in order to examine its association with microbial succession and with the formation of colour-,taste-and flavour-related metabolites.Microbiome profiling revealed that Pol-ygonatum fortification was associated with earlier microbial reorganisation,accompanied by earlier shifts in notable genera such as Staphylococcus and Thermomyces.Under the same piling conditions,the fortified piles showed earlier moderation of bitterness,an earlier transition to a characteristic bright-red infusion,and distinct treatment-related trajectories in volatile compounds.Non-volatile profiling further showed earlier increases in theabrownins and a higher final level in the fortified piles,together with shifts in catechin-derived pigment transformation.Taken together,these results indicate that the introduction of saccharified Polygonatum was associated with coordinated microbial and chemical changes during Liupao tea pile fermentation,providing a useful basis for further investigation of Polygonatum-associated dark-tea fermentation under practical piling conditions.
基金provided by the University of Helsinki Doctoral School in Environmental,Food and Biological Sciences,Finland.
文摘The growing focus on sustainable development is encouraging more people to adopt vegetarian diets and alternative protein sources,increasing the demand for natural sources of vitamin B12.Propionibacterium freudenreichii has been identified as a potent producer of vitamin B12 through fermentation processes.In this study,two distinct batches of beer were produced:one serving as a control comprising probiotic Saccharomyces boulardii CNCM I-745 and Saccharomyces cerevisiae SafAle^(TM) US-05,and the other integrating these yeasts alongside P.freudenreichii DSM 20271.A two-step fermentation approach was adopted,with bacterial fermentation followed by yeast fermentation,to augment the vitamin B12 content in the beer.The application of this methodology resulted in successful enhancement of vitamin B12 levels in the beer,reaching 2.80(±0.3)ng/ml,translating to 1.40(±0.13)μg of vitamin B12 per 500-ml beer bottle.Over the course of an 80-day fermentation period,various parameters including cell counts,sugars,acids,ethanol,volatile compounds and vitamin B12 were monitored.Furthermore,a trained sensory panel was engaged to discern any perceptible differences between the two beer variants.The results suggest that the co-fermented beer exhibited minimal divergence in sensory attributes compared with the yeast-fermented counterpart,implying that the metabolite production by P.freudenreichii did not significantly affect the sensory profile of the beer.This study serves as compelling evidence that the natural fortification of beer with nutritionally significant levels of vitamin B12 can be achieved through fermentation processes involving P.freudenreichii.
基金supported by the National Natural Science Foundation of China(32372368).
文摘Probiotic stability and activity during broth fermentation are crucial for enhancing the flavour and nutritional value of the final product.This study introduces a novel staining technique that allows differentiation of Lacticaseibacillus rhamnosus and Staphylococcus xylosus within sodium alginate(SA)encapsulated microspheres without altering the SA structure.Encapsulation efficiencies were 88.41%for L.rhamnosus and 82.68%for S.xylosus,with the staining technique enhancing thermal stability.Co-fermentation in pork broth resulted in significant increases in organic acids(e.g.,lactic acid from 3.209 g/L to 8.673 g/L and acetic acid),thereby improving sensory attributes.Amino acid analysis revealed substantial increases in essential amino acids,including glutamic acid(from 7.493 mg/100 g to 27.422 mg/100 g)and glycine(from 12.435 mg/100 g to 30.632 mg/100 g),which contributed to an improved nutritional profile.Furthermore,significant increases in volatile compounds,such as isophorone(up to 148.25μg/L),1-Octanol(up to 39.02μg/L),and benzaldehyde(up to 570.84μg/L),enriched the aroma of the pork broth.SA encapsulation maintained probiotic viability throughout the extended fermentation period,while strain interactions further enriched both nutritional and flavour profiles.These findings highlight the potential of SA encapsulation combined with co-fermentation to optimize the sensory and nutritional qualities of fermented foods.
基金supported by the National Natural Science Foun-dation of China(No.32072346)the Cross-Innovation Open Project of Food Flavor and Health(No.FFHCI2025029)+1 种基金Beijing Technology&-Business University,the Science and Technology Commission of Shanghai Municipality(No.22XD1432700)Shanghai Engineering Technology Research Center of Shanghai Science and Technology Commission(No.20DZ2255600).
文摘Kazak cheese is a traditional acid-curd dairy product in China,valued for its unique flavor but limited by inconsistent quality in industrial production.Its flavor profile is primarily determined by lactic acid bacteria(LAB)during fermentation,however,their strain-specific characteristics affect the profiles of volatile com-pounds.This study evaluated the effect of the Lactobacillus casei TCS,Pediococcus pentosaceus 4D,Lactobacillus casei TGA and Lactococcus lactis 408 on the volatile compounds of Kazak cheeses.Using GC-IMS analysis,58 volatile compounds were identified,predominantly acids and ketones,which constituted 75%of the total volatile compounds.Based on ROAV results,acetaldehyde(13.12%-22.20%),acetoin(6.95%-10.06%)significantly contributed to the cheese flavor.Principal component analysis demonstrated that 3-methylbutanal(nutty notes)was correlated with L.lactis 408-fermented Kazak cheese,while diacetyl(milky notes)was asso-ciated with L.casei TGA-fermented cheeses.Furthermore,co-fermentation of L.lactis 408 and L.casei TCS significantly increased acetoin concentration(1406 mg/kg,p<0.01)in Kazak cheese.Additionally,molecular docking analysis revealed that acetoin exhibited higher binding energy with acetoin reductase than that with diacetyl and diacetyl reductase,thereby facilitating the production of 2,3-butanediol.These findings highlight the pivotal roles of microbial metabolism in Kazak cheese flavor and provide insights into optimizing the flavor compositions.
基金supported by the Science and Technology SMES Innovation Ability Improvement Project of Shandong Province,China(Project NO.2023TSGC0980)the Key Research and Development Program of Changzhou,Jiangsu Province,China(Project No.CE20222005).
文摘Lactic acid bacteria(LAB)fermentation has the potential to be an effective way to improve the flavor of foods.In this study,Lactococcus lactis(L.lactis),Lactobacillus plantarum(L.plantarum)and Lactobacillus rhamnosus(L.rhamnosus)co-fermented oat beverage was prepared and both the molecular and biochemical basis for its unique flavor formation were investigated by using cross-correlation analysis combined with untargeted flavoromics.Results showed that via co-fermentation main flavor substances like organic acids,free amino acids(FAAs)and volatile flavor compounds(VFCs)could be regulated dynamically.Interaction network analysis and redundancy analysis(RDA)convinced the crucial roles of three bacteria in shaping the overall flavor profile of co-fermented beverage,especially for the formation of soft sourness,sweetness,and freshness.According to untargeted metabolomics,it could be concluded that co-fermentation regulated significant differential metabolites(56 in total)unique to LAB co-fermented oat beverage such as benzoic acid,DL-arginine,uridine,and citrate.KEGG pathway enrichment analysis further predicted the viable formation pathways of key flavor compounds obtained by RDA such as organic acids(malate,citrate,et al.),FAAs(aspartate,glutamate,et al.)and VFCs(2,3-butanedione,1-nonanol,et al.).This work demonstrates the positive flavor contribution of LAB co-fermentation,providing valuable reference for subsequent multi-omics studies on fermented oat products.
