Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships w...Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships with antioxidant activity and oxidative stability,gas chromatography-mass spectrometry was performed to characterize the associated fatty acid profiles.The antioxidant activity of vegetable oils,based on their DPPH-scavenging capacity(expressed as IC_(50) values),was used to assess their impact on human health,and their oxidative stability was characterized by performing lipid oxidation analysis to determine the oxidative induction time of fats and oils.In addition,correlation analyses were performed to examine associations between the fatty acid composition of the oils and DPPH-scavenging capacity and oxidative stability.The results revealed that among the assessed oils,coffee seed oil has the highest saturated fatty acid content(355.10 mg/g),whereas Garddenia jaminoides oil has the highest unsaturated fatty acid content(844.84 mg/g).Coffee seed oil was also found have the lowest DPPH IC_(50) value(2.30 mg/mL)and the longest oxidation induction time(17.09 h).Correlation analysis revealed a significant linear relationship(P<0.05)between oxidative stability and unsaturated fatty acid content,with lower contents tending to be associated with better oxidative stability.The findings of this study provide reference data for the screening of functional edible vegetable oils.展开更多
Walnuts are rich in a variety of nutritional components.However,due to their high content of unsaturated fatty acids(UFAs),the quality of walnuts tends to decline during storage,which adversely affects the development...Walnuts are rich in a variety of nutritional components.However,due to their high content of unsaturated fatty acids(UFAs),the quality of walnuts tends to decline during storage,which adversely affects the development of the walnut industry.This study was aimed to investigate the impacts of temperature and packaging methods on the storage quality and oxidative stability of walnuts.The Wen 185 walnut variety was selected,and the physical-chemical and nutritional indexes of walnuts stored for 42 weeks under different temperatures(18℃,4℃,and room temperature)and packaging methods(vacuum light-exposed,vacuum light-proof,vacuum-ra-diation light-exposed,vacuum-radiation light-proof,nitrogen-filled light-exposed,nitrogen-filled light-proof)were measured.The results showed that low temperatures,especially18℃,in combination with vacuum lightproof packaging,could effectively suppress the increase in oxidative stability indicators such as acid value(AV)and peroxide value(PV),and maintain high retention rates of nutritional indicators like tocopherol and phytosterol.This study has elucidated that low temperatures and appropriate packaging methods play the crucial roles in maintaining the quality and oxidative stability of walnuts during storage.It has provided comprehensive and valuable data support and theoretical basis for the scientific storage of walnuts,contributing to the devel-opment of the walnut industry and the guarantee of product quality.展开更多
Background Clostridium butyricum(CB)is a probiotic that can regulate intestinal microbial composition and improve meat quality.Rumen protected fat(RPF)has been shown to increase the dietary energy density and provide ...Background Clostridium butyricum(CB)is a probiotic that can regulate intestinal microbial composition and improve meat quality.Rumen protected fat(RPF)has been shown to increase the dietary energy density and provide essential fatty acids.However,it is still unknown whether dietary supplementation with CB and RPF exerts beneficial effects on growth performance and nutritional value of goat meat.This study aimed to investigate the effects of dietary CB and RPF supplementation on growth performance,meat quality,oxidative stability,and meat nutritional value of finishing goats.Thirty-two goats(initial body weight,20.5±0.82 kg)were used in a completely randomized block design with a 2 RPF supplementation(0 vs.30 g/d)×2 CB supplementation(0 vs.1.0 g/d)factorial treatment arrangement.The experiment included a 14-d adaptation and 70-d data and sample collection period.The goats were fed a diet consisted of 400 g/kg peanut seedling and 600 g/kg corn-based concentrate(dry matter basis).Result Interaction between CB and RPF was rarely observed on the variables measured,except that shear force was reduced(P<0.05)by adding CB or RPF alone or their combination;the increased intramuscular fat(IMF)content with adding RPF was more pronounced(P<0.05)with CB than without CB addition.The pH24h(P=0.009),a*values(P=0.007),total antioxidant capacity(P=0.050),glutathione peroxidase activities(P=0.006),concentrations of 18:3(P<0.001),20:5(P=0.003)and total polyunsaturated fatty acids(P=0.048)were increased,whereas the L*values(P<0.001),shear force(P=0.050)and malondialdehyde content(P=0.044)were decreased by adding CB.Furthermore,CB supplementation increased essential amino acid(P=0.027),flavor amino acid(P=0.010)and total amino acid contents(P=0.024)as well as upregulated the expression of lipoprotein lipase(P=0.034)and peroxisome proliferator-activated receptorγ(PPARγ)(P=0.012),and downregulated the expression of stearoyl-CoA desaturase(SCD)(P=0.034).The RPF supplementation increased dry matter intake(P=0.005),averaged daily gain(trend,P=0.058),hot carcass weight(P=0.046),backfat thickness(P=0.006),concentrations of 16:0(P<0.001)and c9-18:1(P=0.002),and decreased the shear force(P<0.001),isoleucine(P=0.049)and lysine content(P=0.003)of meat.In addition,the expressions of acetyl-CoA carboxylase(P=0.003),fatty acid synthase(P=0.038),SCD(P<0.001)and PPARγ(P=0.022)were upregulated due to RPF supplementation,resulting in higher(P<0.001)content of IMF.Conclusions CB and RPF could be fed to goats for improving the growth performance,carcass traits and meat quality,and promote fat deposition by upregulating the expression of lipogenic genes of Longissimus thoracis muscle.展开更多
In order to select an appropriate deacidification process and improve the quality of walnut oil,low-temperature cold-pressed crude walnut oil was used as raw material.Deacidified walnut oil was prepared using three de...In order to select an appropriate deacidification process and improve the quality of walnut oil,low-temperature cold-pressed crude walnut oil was used as raw material.Deacidified walnut oil was prepared using three deacidification processes:chemical deacidification(CD),adsorption deacidification(AD),and molecular distillation deacidification(MDD).The physicochemical properties,nutritional components,and in vitro antioxidant activities of the resulting deacidified walnut oils were comparatively analyzed.The results indicate that the fatty acid content in walnut oil exhibits fluctuating changes during the three different deacidification processes.The MDD shows a higher deacidification rate,reaching 94.06%,which is superior to the other two methods.Additionally,the AD retains more total phenols and tocopherols,with retention rates of 95.79%and 74.62%,respectively;whereas MDD is more effective at retaining phytosterols,achieving a retention rate of 98.09%.All these methods displayed positive impacts on the in vitro antioxidant capacity and oil stability of walnut oil,with ferric-reducing antioxidant power(FRAP)content and oxidative stability time were significantly reduced.-whencompared to the untreated crude oil Among them,AD had the greatest impact on oxidative stability index(OSI),with its decreasing from 2.06 h to 0.82 h.Overall,compared to CD or MDD,the AD has best application prospects in preserving nutritional components.展开更多
Linusorbs(LOs),particularly the Methionine(Met)-containing yet Tryptophan(Trp)-free LO(CLB and CLP),play a significant role in shaping the quality and sensory attributes of flaxseed oil.To investigate the stability of...Linusorbs(LOs),particularly the Methionine(Met)-containing yet Tryptophan(Trp)-free LO(CLB and CLP),play a significant role in shaping the quality and sensory attributes of flaxseed oil.To investigate the stability of these LOs and their oxidized forms during accelerated oxidation,the polar fractions of crude flaxseed oil were selectively removed using silica absorption and then reintroduced separately into the oil matrix along with LOs andγ-tocopherol(γ-T).Through comprehensive analysis of oxidative stability indexes,LOs content changes,oxidation kinetics,and the correlation between LOs and oxidative stability indexes,we observed that the LOs fraction alone exhibited a moderate antioxidant effect on the peroxide value(PV)but a weaker effect on the panisidine value(p-AV)of flaxseed oil.However,upon addition ofγ-T,we observed a weak synergistic effect betweenγ-T and LOs in suppressing PV,while a stronger effect in suppressing p-AV.Additionally,a comparison of the oxidation kinetics of different LOs indicated thatγ-T preferentially protected the oxidation of CLP over CLB.Similar protective trends ofγ-T towards the methionine sulfoxide(MetO)and methionine sulfoxide(MetO2)form of LOs were also observed,albeit to a lesser extent.Correlation analysis revealed that changes in Metcontaining LOs,particularly CLP,showed a high correlation with PV in the tested matrices,while MetOcontaining LOs better depicted changes in p-AV.Importantly,CLP demonstrated higher susceptibility to the influence of antioxidants,making it more suitable for evaluating the peroxide value in flaxseed oil samples.展开更多
To investigate the effects of a synthetic isoflavone （SI） on meat quality and oxidative stability, 1 500 43-d-old Lingnan yellow male broilers were randomly assigned to five dietary treatments： diets supplemented w...To investigate the effects of a synthetic isoflavone （SI） on meat quality and oxidative stability, 1 500 43-d-old Lingnan yellow male broilers were randomly assigned to five dietary treatments： diets supplemented with 0, 10, 20, 40, or 80 mg SI kg-1, fed ad libitum for a period of 3 wk. After refrigerated storage, a＊ value of the meat increased with dietary SI supplementation using 10 and 40 mg kg-1 level （P〈0.05）, L＊ value decreased （P〈0.05）, and 40 mg kg-j increased the pH （P〈0.05）. Supplementation with SI, at all levels, increased water holding capacity （P〈0.05） and decreased lactic acid content of meat （P〈0.05）. The concentration of malondialdehyde at 72 h decreased linearly （P=0.005） and quadratically （P=0.004） with increasing levels of SI. Dietary SI at 20 and 40 mg kg-1 levels enhanced total superoxide dismutase activity in meat （P〈0.05）. Meat pH quadratically decreased as the storage time increased （P〈0.05）, with the highest value at 24 h （P〈0.05）. Lactic acid and malondialdehyde concentrations of meat increased over time, with value at 96 h being far higher than at earlier times （P〈0.05）. Supplemental SI linearly and quadratically increased the mRNA abundance ofglutathione peroxidase （GPX） （P=0.001 and P=0.002） and catalase （CAT） （P=0.003 and P=0.006） in breast muscle. The results from this study indicate that dietary supplementation with SI can improve meat quality during refrigerated storage by decreasing lipid peroxidation and enhancing oxidative stability and, for male broilers from 43 to 63 d of age, the optimal level of SI was 40 mg kg-1.展开更多
Biodiesel(fatty acid alkyl esters),an alternate to fossil fuel,has the tendency of autoxidation and hence requires antioxidants for long term storage.The influence of synthetic and natural antioxidants on the oxidativ...Biodiesel(fatty acid alkyl esters),an alternate to fossil fuel,has the tendency of autoxidation and hence requires antioxidants for long term storage.The influence of synthetic and natural antioxidants on the oxidative stability was analysed for fresh FAMEs(fatty acid methyl esters)obtained from hevea brasiliensis at 140 C.Higher activity was observed for synthetic antioxidants following the order of GA】BHT】DTBP】Q】GT-M】PH-M】GT-C,whereas the oxidative stability of stored FAMEs samples measured at 110 C reveals a nearly inverse trend.Storage stability was tested for the FAMEs obtained from hevea brasiliensis stored at 30 C,after addition of synthetic and natural antioxidants—butylated hydroxytoluene(BHT),2,6-di-tert-butylphenol(DTBP),quercetin(Q),gallic acid(GA),methanol extracts from green tea(GTM),pomegranate hull(PH-M),and chloroform extract of green tea(GT-C).Antioxidant activities above 1500 ppm was in the order of DTBP】BHT】GA】GT-C】GT-M】Q】PH-M.Synthetic antioxidants have been found more efficient to improve the storage stability of FAMEs obtained from hevea brasiliensis.DTBP in particular has the highest protection factor.展开更多
Forty-two (42) finishing pigs (entire males—EM, surgical castrates—SC and gilts—G, each of 14)—progeny of Landracesows and Hampshire × Pietrain boars, were included in the trial. They were randomly divided in...Forty-two (42) finishing pigs (entire males—EM, surgical castrates—SC and gilts—G, each of 14)—progeny of Landracesows and Hampshire × Pietrain boars, were included in the trial. They were randomly divided into control and experimental groups(each of seven). Control groups were fed the standard diet without any supplement. Experimental groups received standard diet withthe same composition as control but with supplement of creatine monohydrate (CMH, 2.0 g/kg of feed) for 30 d prior to slaughter.Sex of pigs had significant effect (p < 0.05) on drip loss and tenderness of pork when EM showed higher drip loss than SC and lowertenderness compared to other two groups (4.71% vs. 3.80%, resp. 3.23 vs. 3.91 and 4.12). Creatine level in plasma was increased byCMH supplementation in 46% in EM, 43% in SC and 41% in G. Similarly, concentration of phosphocreatine (PCr) in muscleincreased in 84% in EM, 88% in SC and 83% in G, respectively. CMH also improved meat colour L* (50.03 vs. 48.88) and reduceddrip loss in both EM (5.24% vs. 4.18%) and G (4.48% vs. 3.60%). Higher tenderness and better oxidative stability of pork after CMHsupplementation was found in all three sexes.展开更多
The increasing demand of natural food from consumers has limited the use of traditional methods to control the oxidation of lipids,such as synthetic antioxidants and hydrogenation.Besides,it has been reported that the...The increasing demand of natural food from consumers has limited the use of traditional methods to control the oxidation of lipids,such as synthetic antioxidants and hydrogenation.Besides,it has been reported that the use of enzymes is efficient to eliminate dissolved oxygen in foods such as vegetable oils.Laccase is a polyphenol oxidase and the reduction of oxygen to water is accompanied by the oxidation,typically,of a phenolic substrate.Laccase have become important,industrially relevant enzymes that can be used for a number of diverse applications such waste detoxification,textile dye transformation,food technologic uses,biosensor and analytical applications,bioethanol production,among others.The target of this study was to evaluate the effect of laccase enzyme from Trametes versicolor,on the oxidative stability of sesame,chia,peanut and sunflower oils,measured through the peroxide value(PV)and conjugated dienes(K232)and trienes(K270).The samples of oil with laccase showed higher PV,K232 and K270 than their corresponding controls,under the conditions evaluated(room temperature and 60◦C).The results suggest that fungal laccase has an unexpected pro-oxidant effect on vegetable oils,possibly promoted by products derived from the oxidation of phenols by enzymatic action.展开更多
Flaxseed oil,a key source of plant-based ω-3α-linolenic acid,is susceptible to oxidation and hazardous substance formation during refining and storage.This study evaluated the effects of refining stages(crude,degumm...Flaxseed oil,a key source of plant-based ω-3α-linolenic acid,is susceptible to oxidation and hazardous substance formation during refining and storage.This study evaluated the effects of refining stages(crude,degumming,complete refining)on aldehydes,trans fatty acids,and oxidative stability in flaxseed oil.The results indicate that heat-pressed oil has dark color with high a*and b*values,but exhibits the relatively highest oxidative stability during the oxidation process.However,compared to cold-pressing,heat-pressing promotes the generation of three additional aldehydes,butenal,nonanal,and trans,trans-2,4-decadienal.Degumming optimizes the color of crude oil while maintaining α-linolenic acid.In contrast,complete refining(degumming,deacidification,bleaching,and deodorization)caused the loss of substantial carotenoids and polyphenols,and α-linolenic acid decreased by 3.48%–4.47%,as well as a large amount of production of trans fatty acids.In addition,complete refining not only leads to the formation of newborn acrolein and trans-2-nominal but also results in a significant increase in most aldehydes concentration.This study provides a reference for the processing of flaxseed oil when considering the formation of hazardous substances induced by the oxidation and isomerization of polyunsaturated fatty acids.展开更多
The aim of the present study was to investigate the effect of dietary supplementation with sugar cane extract(SCE) on meat quality and oxidative stability of Longissimus dorsi muscle in finishing pigs.Eighteen barrows...The aim of the present study was to investigate the effect of dietary supplementation with sugar cane extract(SCE) on meat quality and oxidative stability of Longissimus dorsi muscle in finishing pigs.Eighteen barrows(Duroc × Landrace × Jiaxing Black), with an average initial body weight of 62.1 ± 5.0 kg,were randomly allotted to 1 of 3 diets with 6 replicates per treatment for 42 days. The diets comprised a normal diet and the normal diets supplemented with 5 and 25 g/kg SCE. The results showed that SCE supplementation did not affect final body weight of finishing pigs. Dietary SCE supplementation significantly increased(P < 0.05) Longissimus dorsi muscle pH_(24 h),and tended to reduce(P < 0.1) and significantly decreased(P < 0.05) shear force, drip loss, myofiber cross sectional area and lactate dehydrogenase activity at 5 and 25 g/kg, respectively. Meanwhile, dietary SCE treatments significantly decreased(P < 0.05) malonaldehyde content and total superoxide dismutase activity in Longissimus dorsi muscle, and tended to reduce(P < 0.1) malonaldehyde content in serum. Altogether, these data indicate that SCE is an effective feed additive to improve pork meat quality, and the underlying mechanism may be partly due to the improved oxidative stability induced by dietary SCE supplementation.展开更多
Oxidative deterioration of vegetable oils is of great importance in the food industry.In China,vegetable oils produced via thermal pretreatment are popular owing to their strong oil flavor and enhanced yield.Here,we r...Oxidative deterioration of vegetable oils is of great importance in the food industry.In China,vegetable oils produced via thermal pretreatment are popular owing to their strong oil flavor and enhanced yield.Here,we review:(i)the currently employed thermal treatment methods of oilseeds before oil extraction;(ii)effects of thermal treatments on the physicochemical properties,contents of minor lipid components,and oxidative stability of vegetable oils;and(iii)Maillard model systems that are related to oil and oilseed chemistry.Among the thermal pretreatment technologies,microwave and infrared radiations are promising,but these are not performed on the same large production scales as roasting.For most oilseeds,thermal treatments increase the yield of extracted oil and content of minor lipid compounds in the oil,such as polyphenols,tocopherols,and phytosterols.In addition,some Maillard reaction products(MRPs)generated by heating oilseeds have been extracted.The presence of both minor lipids and MRPs in the oil confers improved oxidative stability.However,the mechanism or relationship between thermal treatment and oxidative stability is yet to be clearly elucidated because vegetable oil oxidation is dependent on variables such as unsaturation,concentration and types of minor lipid components,MRPs,and the potential synergistic effects of these components.Recently,several Maillard reaction models related to thermally treated oilseeds have been established,suggesting that MRPs play a critical role during oxidation.However,comprehensive identification of antioxidants and the mechanism by which they inhibit oxidation are lacking.Future research can be performed to establish models that would help elucidate the antioxidative mechanisms of MRPs for more oilseeds.Using these models,it will be possible to predict the oil quality after processing,based on the presence of MRPs and oil chemistry.展开更多
Fatliquor oxidation may give leather unpleasant odor,and excessive amounts of Cr(VI)and volatile organic com-pounds.The accurate evaluation and improvement of the oxidative stability of fatliquors are of great signifi...Fatliquor oxidation may give leather unpleasant odor,and excessive amounts of Cr(VI)and volatile organic com-pounds.The accurate evaluation and improvement of the oxidative stability of fatliquors are of great significance to high-quality leather manufacturing.We proposed a set of practical methods for evaluating the oxidative stability of fatliquors on the basis of oxidation induction time,change in iodine value(∆IV),and change in acid value(∆AV)under accelerated oxidation conditions(at 100°C with 10 L/h of air).Oxidation induction time is a highly sensitive marker for quantifying the oxidative stability of fatliquors,and∆IV and∆AV that are low cost and easy to operate are useful in evaluating the oxidative stability of fatliquors when the oxidation induction time is less than 22 h.The number of double bonds in fatliquors is an important factor affecting oxidative stability.The sulfation modification of fatliquors that greatly reduces double bonds and the addition of antioxidants,especially butylated hydroxyanisole and butylated hydroxytoluene,markedly improve oxidative stability of fatliquors.展开更多
Nanoemulsion systems were employed to encapsulate the orange peel extract obtained from conventional maceration and novel ultrasound assisted extraction technology.Different wall materials maltodextrin(MD),whey protei...Nanoemulsion systems were employed to encapsulate the orange peel extract obtained from conventional maceration and novel ultrasound assisted extraction technology.Different wall materials maltodextrin(MD),whey protein isolate(WPI)and complex maltodextrin and whey protein isolate(MD/WPI)(1:1)were used in order to enhance the nanoemulsion stability,protect the bioactive core from degradation and control the release of bioactive compounds.The freeze drying technology was then used to obtain powder encapsulates with encapsulation efficiency and loading capacity of MD,WPI and MD/WPI as 89.3,91.2,95.6%and 95.3,94.4 and 93.1%respectively which depicts that encapsulation has taken place properly.All emulsions obtained were in nanoscale range with average hydrodynamic diameter as 105.0,201.82,215.12 and 298.82 for primary W/O emulsion,MD,WPI and MD/WPI stabilised emulsions respectively.These encapsulates were then incorporated in soyabean and mustard oil at different concentration 100,200 and 300 ppm and compared with free extract and synthetic antioxidant BHT to enhance storage life by controlling the oxidative changes during accelerated shelf life storage at 60o C for 24 days.The results obtained concluded that nanoencapsulated extracts performed better in prevention of oxidative indices than the free extract.However,nanocapsules encapsulated by MD/WPI exhibited higher protection of oils during storage than the maltodextrin and whey protein isolate.展开更多
During storage,olive oil may suffer degradation leading to an inferior quality level when purchased and consumed.Oxidative stability is one of the most important parameters for maintaining the quality of olive oil,whi...During storage,olive oil may suffer degradation leading to an inferior quality level when purchased and consumed.Oxidative stability is one of the most important parameters for maintaining the quality of olive oil,which affects its acceptability and market value.The current methods of predicting the oxidative stability of edible oils are costly and time-consuming.The aim of the present research is to demonstrate the use of dielectric spectroscopy integrated with computer vision for determining the oxidative stability index(OSI)of olive oil.The most effective features were selected from the extracted dielectric and visual features for each olive oil sample.Three machine learning techniques were employed to process the raw data to develop an oxidative stability prediction algorithm,including artificial neural network(ANN),support vector machine(SVM)and multiple linear regression(MLR).The predictive models showed a great agreement with the results obtained by the Rancimat instrument that was used as a reference method.The best result for modelling the oxidative stability of olive oil was obtained using SVM technique with the R-value of 0.979.It can be concluded that this new approach may be utilized as a perfect replacement for quicker and cheaper assessment of olive oil oxidation.展开更多
Beeswax can be a good structuring agent for edible oleogels.There is controversy about its role in the oleogel oxidation processes.This study investigated the oxidative stability of oleogels and the impact of their co...Beeswax can be a good structuring agent for edible oleogels.There is controversy about its role in the oleogel oxidation processes.This study investigated the oxidative stability of oleogels and the impact of their composition and texture on this stability.Oleogels were created by structuring sunflower oil with beeswax or combinations of its fractions(6%w/w gelator).Preparative flash chromatography was used to obtain beeswax fractions,which had a diverse composition according to TLC and HPLS-ELSD(hydrocarbons,wax esters,free fatty acids,and alcohols).Different oxidation indices(PV,AV,CDV,TOTOX,volatile organic compounds)of oleogels were evaluated,as well as their textural properties(firmness and Young’s modulus)after 20 days of storage at 35◦C.Among the tested samples,unstructured sunflower oil demonstrated the highest oxidative stability.The sample based on hydrocarbons and monoesters was the most stable of the oleogels tested.Hexanal is the most common volatile organic molecule generated during the oxidation of sunflower oil.Oleogels have a more complex profile of volatile compounds,including ketones,alcohols,and terpenes.Beeswax based oleogel’s induction period was the shortest.The oxidation rate of oleogels and Young’s modulus(r2=0.9511,negative),as well as the concentration of free fatty acids(r2=0.8195,positive)had a strong correlations.The results show that oleogels structured with beeswax fractions could be beneficial in fat-containing products with improved oxidation resistance.展开更多
This study aims to enhance the oxidative stability of njangsa seed oil(NSO)through encapsulation by ionic gelation using sodium alginate(ALG)solely or in combination with Bambara groundnut protein isolate(BPI)as wall ...This study aims to enhance the oxidative stability of njangsa seed oil(NSO)through encapsulation by ionic gelation using sodium alginate(ALG)solely or in combination with Bambara groundnut protein isolate(BPI)as wall materials.The encapsulation efficiency(EE)and loading capacity of the microcapsules produced using ALG and ALG-BPI were 73.76 and 76.30%and 57.99 and 61.48%,respectively.Confocal microscopic analysis showed an even distribution of NSO within the ALG-BPI microcapsules,which was confirmed by FTIR analysis.The scanning electron microscopy(SEM)analysis revealed a rough and porous structure for ALG-NSO,which ex-plains the higher NSO released of 22.29 and 78.51%during simulated gastric and intestinal digestion,respec-tively compared to ALG-BPI-NSO.Higher melting and degradation temperatures were obtained for ALG-BPI-NSO(304.76℃)compared to ALG-NSO(286.94℃).The free fatty acid content,peroxide,p-anisidine,and thio-barbituric acid values of encapsulated NSO were lower than in the free oil throughout the 21-day study period,with NSO encapsulated in ALG-BPI showing higher improved oxidative stability than with alginate alone.The study provided valuable information on fabricating an alginate-Bambara groundnut protein isolate-based effective delivery system for NSO.展开更多
Fatty acid composition and triacylglycerols(TAG)profile of chia seed oil were determined.The main fatty acids present in the tested oil wereα-linolenic acid(Ln,61.1%)>linoleic acid(L,16.6%)>palmitic acid(P,6.7%...Fatty acid composition and triacylglycerols(TAG)profile of chia seed oil were determined.The main fatty acids present in the tested oil wereα-linolenic acid(Ln,61.1%)>linoleic acid(L,16.6%)>palmitic acid(P,6.7%)>oleic acid(O,6.0%)>stearic acid(S,3.2%).Five major triacylglycerols in chia oil were LnLnLn,LnLLn,LnLnP,LnOLn,and LLLn and these contributed more than 76%to the total.The oxidative stability under autoxidative and photooxidative conditions before and after the removal of their minor components was also determined.In addition,tocols,chlorophylls and carotenoids were measured in the oil.Oil samples were stripped of their minor components by using a facile silicic acid and charcoal in one pot rather than in a column.Storage under Schaal oven condition and photooxidation were also monitored for both crude oil(non-stripped)and stripped oil using stationary phase material.Total tocopherol contents were in the order ofβ−/γ-282.68,δ-47.44,andα-tocopherols 10.94 mg/kg of oil.Stripping removed all the minor components including tocopherols,chlorophylls and carotenoids.Oxidative stability of the tested seed oil was primarily affected by its composition of fatty acids,triacylglycerols,minor components,and storage conditions.展开更多
The sulfonated poly(α-methyl styrene-b-isobutylene-b-α-methyl styrene)copolymers(S-ASIBS)with the average molar percentage of sulfonic acid(-SO_(3)H)groups(SP)ranging from 3.6 mol%to 14.3 mol%could be synthesized by...The sulfonated poly(α-methyl styrene-b-isobutylene-b-α-methyl styrene)copolymers(S-ASIBS)with the average molar percentage of sulfonic acid(-SO_(3)H)groups(SP)ranging from 3.6 mol%to 14.3 mol%could be synthesized by sulfonation of ASIBS with acetyl sulfate.The hydrophilic ionic channels were generated for proton exchange membranes(PEMs)by ion aggregation of-SO_(3)H groups and microphase separation between hydrophobic polyisobutylene and hydrophilic sulfonated poly(α-methyl styrene)segments in S-ASIBS.The proton transport ability was improved while oxidative stability was decreased by increasing SP in S-ASIBS.The appropriate SP of about 12.7 mol%in S-ASIBS provides the available PEMs with high proton transport ability,low methanol permeability and good oxidative stability.The absence of active tertiary hydrogen atoms along S-ASIBS copolymer chains avoids their attack by peroxy radicals.The residual rates of weight(RW)and proton conductivity(Rσ)of S-ASIBS-12.7 membrane after oxidation treatment for 916 h were 84.3%and 88.1%respectively,near to those of commercial Nafion 117(RW=87.9%,Rσ=90.3%).The membrane electrode assembly(MEA)could be prepared by using various S-ASIBS as PEMs for direct methanol fuel cell.The single cell with S-ASIBS-12.7 MEA behaves high performance of open circuit voltage(OCV)of 548 mV and peak power density(Pmax)of 36.1 mW·cm^(-2),which is similar to those of Nafion 117(OCV=506 mV,P_(max)=35.6 mW·cm^(-2)).To the best of our knowledge,this is the first example of advanced S-ASIBS membrane with high proton conductivity,excellent fuel barrier property and remarkable oxidative stability for promising PEMs.展开更多
The oxidative and physical stability of the reformulated mayonnaise with processed beetroot was investigated and compared with a control(mayonnaise without beetroot)and a commercially available product.Processing of b...The oxidative and physical stability of the reformulated mayonnaise with processed beetroot was investigated and compared with a control(mayonnaise without beetroot)and a commercially available product.Processing of beetroot had an impact on the structural integrity of the antioxidants present.Microwaving(960 W for 7 min)was advantageous for preserving the betalain and polyphenol content of beetroot compared to roasting(180◦C for 90 min)and boiling(100◦C for 30 min).The oxidative stability of mayonnaise samples was determined by Rancimat and the thiobarbituric(TBA)assay.The addition of microwaved beetroot significantly enhanced the oxidative stability of mayonnaise at the end of a storage period of 4 weeks(4◦C).Although no significant differences(P>0.05)were detected between the mayonnaise samples containing beetroot and the commercial control,the latter was less susceptible to oxidation during storage.The turbiscan stability index(TSI)revealed that the commercial mayonnaise was less prone to destabilization phenomena.All the textural parameters increased with the incorporation of beetroot.The sensory evaluation revealed that,with the exception of graininess and uniformity,most of the sensory attributes are preserved if not improved with the addition of beetroot.展开更多
文摘Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships with antioxidant activity and oxidative stability,gas chromatography-mass spectrometry was performed to characterize the associated fatty acid profiles.The antioxidant activity of vegetable oils,based on their DPPH-scavenging capacity(expressed as IC_(50) values),was used to assess their impact on human health,and their oxidative stability was characterized by performing lipid oxidation analysis to determine the oxidative induction time of fats and oils.In addition,correlation analyses were performed to examine associations between the fatty acid composition of the oils and DPPH-scavenging capacity and oxidative stability.The results revealed that among the assessed oils,coffee seed oil has the highest saturated fatty acid content(355.10 mg/g),whereas Garddenia jaminoides oil has the highest unsaturated fatty acid content(844.84 mg/g).Coffee seed oil was also found have the lowest DPPH IC_(50) value(2.30 mg/mL)and the longest oxidation induction time(17.09 h).Correlation analysis revealed a significant linear relationship(P<0.05)between oxidative stability and unsaturated fatty acid content,with lower contents tending to be associated with better oxidative stability.The findings of this study provide reference data for the screening of functional edible vegetable oils.
基金Key Technology Research and Development Program in Autonomous Region(2022A02009)Agricultural Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2021-OCRI).
文摘Walnuts are rich in a variety of nutritional components.However,due to their high content of unsaturated fatty acids(UFAs),the quality of walnuts tends to decline during storage,which adversely affects the development of the walnut industry.This study was aimed to investigate the impacts of temperature and packaging methods on the storage quality and oxidative stability of walnuts.The Wen 185 walnut variety was selected,and the physical-chemical and nutritional indexes of walnuts stored for 42 weeks under different temperatures(18℃,4℃,and room temperature)and packaging methods(vacuum light-exposed,vacuum light-proof,vacuum-ra-diation light-exposed,vacuum-radiation light-proof,nitrogen-filled light-exposed,nitrogen-filled light-proof)were measured.The results showed that low temperatures,especially18℃,in combination with vacuum lightproof packaging,could effectively suppress the increase in oxidative stability indicators such as acid value(AV)and peroxide value(PV),and maintain high retention rates of nutritional indicators like tocopherol and phytosterol.This study has elucidated that low temperatures and appropriate packaging methods play the crucial roles in maintaining the quality and oxidative stability of walnuts during storage.It has provided comprehensive and valuable data support and theoretical basis for the scientific storage of walnuts,contributing to the devel-opment of the walnut industry and the guarantee of product quality.
基金supported by the National Key Research and Development Program of China(2022YFD1301105)the earmarked fund for CARS(CARS-36)+2 种基金the Natural Science Foundation of Heilongjiang Province(YQ2021C018)the Postdoctoral Foundation of Heilongjiang Province(LBH-Z21100)the Open Project Program of International Joint Research Laboratory in Universities of Jiangsu Province of China for Domestic Animal Germplasm Resources and Genetic Improvement(IJRLD-KF202204).
文摘Background Clostridium butyricum(CB)is a probiotic that can regulate intestinal microbial composition and improve meat quality.Rumen protected fat(RPF)has been shown to increase the dietary energy density and provide essential fatty acids.However,it is still unknown whether dietary supplementation with CB and RPF exerts beneficial effects on growth performance and nutritional value of goat meat.This study aimed to investigate the effects of dietary CB and RPF supplementation on growth performance,meat quality,oxidative stability,and meat nutritional value of finishing goats.Thirty-two goats(initial body weight,20.5±0.82 kg)were used in a completely randomized block design with a 2 RPF supplementation(0 vs.30 g/d)×2 CB supplementation(0 vs.1.0 g/d)factorial treatment arrangement.The experiment included a 14-d adaptation and 70-d data and sample collection period.The goats were fed a diet consisted of 400 g/kg peanut seedling and 600 g/kg corn-based concentrate(dry matter basis).Result Interaction between CB and RPF was rarely observed on the variables measured,except that shear force was reduced(P<0.05)by adding CB or RPF alone or their combination;the increased intramuscular fat(IMF)content with adding RPF was more pronounced(P<0.05)with CB than without CB addition.The pH24h(P=0.009),a*values(P=0.007),total antioxidant capacity(P=0.050),glutathione peroxidase activities(P=0.006),concentrations of 18:3(P<0.001),20:5(P=0.003)and total polyunsaturated fatty acids(P=0.048)were increased,whereas the L*values(P<0.001),shear force(P=0.050)and malondialdehyde content(P=0.044)were decreased by adding CB.Furthermore,CB supplementation increased essential amino acid(P=0.027),flavor amino acid(P=0.010)and total amino acid contents(P=0.024)as well as upregulated the expression of lipoprotein lipase(P=0.034)and peroxisome proliferator-activated receptorγ(PPARγ)(P=0.012),and downregulated the expression of stearoyl-CoA desaturase(SCD)(P=0.034).The RPF supplementation increased dry matter intake(P=0.005),averaged daily gain(trend,P=0.058),hot carcass weight(P=0.046),backfat thickness(P=0.006),concentrations of 16:0(P<0.001)and c9-18:1(P=0.002),and decreased the shear force(P<0.001),isoleucine(P=0.049)and lysine content(P=0.003)of meat.In addition,the expressions of acetyl-CoA carboxylase(P=0.003),fatty acid synthase(P=0.038),SCD(P<0.001)and PPARγ(P=0.022)were upregulated due to RPF supplementation,resulting in higher(P<0.001)content of IMF.Conclusions CB and RPF could be fed to goats for improving the growth performance,carcass traits and meat quality,and promote fat deposition by upregulating the expression of lipogenic genes of Longissimus thoracis muscle.
基金Key Technology Research and Development Program in Autonomous Region(2022A02009)Agricultural Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2022-OCRI).
文摘In order to select an appropriate deacidification process and improve the quality of walnut oil,low-temperature cold-pressed crude walnut oil was used as raw material.Deacidified walnut oil was prepared using three deacidification processes:chemical deacidification(CD),adsorption deacidification(AD),and molecular distillation deacidification(MDD).The physicochemical properties,nutritional components,and in vitro antioxidant activities of the resulting deacidified walnut oils were comparatively analyzed.The results indicate that the fatty acid content in walnut oil exhibits fluctuating changes during the three different deacidification processes.The MDD shows a higher deacidification rate,reaching 94.06%,which is superior to the other two methods.Additionally,the AD retains more total phenols and tocopherols,with retention rates of 95.79%and 74.62%,respectively;whereas MDD is more effective at retaining phytosterols,achieving a retention rate of 98.09%.All these methods displayed positive impacts on the in vitro antioxidant capacity and oil stability of walnut oil,with ferric-reducing antioxidant power(FRAP)content and oxidative stability time were significantly reduced.-whencompared to the untreated crude oil Among them,AD had the greatest impact on oxidative stability index(OSI),with its decreasing from 2.06 h to 0.82 h.Overall,compared to CD or MDD,the AD has best application prospects in preserving nutritional components.
基金supported by the National Natural Science Foundation of China (Grant No.31920103012 and 32372356)Guangzhou Basic and Applied Basic Research Foundation (Grant No.202201010535).
文摘Linusorbs(LOs),particularly the Methionine(Met)-containing yet Tryptophan(Trp)-free LO(CLB and CLP),play a significant role in shaping the quality and sensory attributes of flaxseed oil.To investigate the stability of these LOs and their oxidized forms during accelerated oxidation,the polar fractions of crude flaxseed oil were selectively removed using silica absorption and then reintroduced separately into the oil matrix along with LOs andγ-tocopherol(γ-T).Through comprehensive analysis of oxidative stability indexes,LOs content changes,oxidation kinetics,and the correlation between LOs and oxidative stability indexes,we observed that the LOs fraction alone exhibited a moderate antioxidant effect on the peroxide value(PV)but a weaker effect on the panisidine value(p-AV)of flaxseed oil.However,upon addition ofγ-T,we observed a weak synergistic effect betweenγ-T and LOs in suppressing PV,while a stronger effect in suppressing p-AV.Additionally,a comparison of the oxidation kinetics of different LOs indicated thatγ-T preferentially protected the oxidation of CLP over CLB.Similar protective trends ofγ-T towards the methionine sulfoxide(MetO)and methionine sulfoxide(MetO2)form of LOs were also observed,albeit to a lesser extent.Correlation analysis revealed that changes in Metcontaining LOs,particularly CLP,showed a high correlation with PV in the tested matrices,while MetOcontaining LOs better depicted changes in p-AV.Importantly,CLP demonstrated higher susceptibility to the influence of antioxidants,making it more suitable for evaluating the peroxide value in flaxseed oil samples.
基金supported by Grant Agreement from Guangdong Provincial Natural Science Fund Committee (S2012010010432)the Earmarked Fund for Modern Agro-Industry Technology Research System (CARS-42) from Ministry of Agriculture,China
文摘To investigate the effects of a synthetic isoflavone （SI） on meat quality and oxidative stability, 1 500 43-d-old Lingnan yellow male broilers were randomly assigned to five dietary treatments： diets supplemented with 0, 10, 20, 40, or 80 mg SI kg-1, fed ad libitum for a period of 3 wk. After refrigerated storage, a＊ value of the meat increased with dietary SI supplementation using 10 and 40 mg kg-1 level （P〈0.05）, L＊ value decreased （P〈0.05）, and 40 mg kg-j increased the pH （P〈0.05）. Supplementation with SI, at all levels, increased water holding capacity （P〈0.05） and decreased lactic acid content of meat （P〈0.05）. The concentration of malondialdehyde at 72 h decreased linearly （P=0.005） and quadratically （P=0.004） with increasing levels of SI. Dietary SI at 20 and 40 mg kg-1 levels enhanced total superoxide dismutase activity in meat （P〈0.05）. Meat pH quadratically decreased as the storage time increased （P〈0.05）, with the highest value at 24 h （P〈0.05）. Lactic acid and malondialdehyde concentrations of meat increased over time, with value at 96 h being far higher than at earlier times （P〈0.05）. Supplemental SI linearly and quadratically increased the mRNA abundance ofglutathione peroxidase （GPX） （P=0.001 and P=0.002） and catalase （CAT） （P=0.003 and P=0.006） in breast muscle. The results from this study indicate that dietary supplementation with SI can improve meat quality during refrigerated storage by decreasing lipid peroxidation and enhancing oxidative stability and, for male broilers from 43 to 63 d of age, the optimal level of SI was 40 mg kg-1.
文摘Biodiesel(fatty acid alkyl esters),an alternate to fossil fuel,has the tendency of autoxidation and hence requires antioxidants for long term storage.The influence of synthetic and natural antioxidants on the oxidative stability was analysed for fresh FAMEs(fatty acid methyl esters)obtained from hevea brasiliensis at 140 C.Higher activity was observed for synthetic antioxidants following the order of GA】BHT】DTBP】Q】GT-M】PH-M】GT-C,whereas the oxidative stability of stored FAMEs samples measured at 110 C reveals a nearly inverse trend.Storage stability was tested for the FAMEs obtained from hevea brasiliensis stored at 30 C,after addition of synthetic and natural antioxidants—butylated hydroxytoluene(BHT),2,6-di-tert-butylphenol(DTBP),quercetin(Q),gallic acid(GA),methanol extracts from green tea(GTM),pomegranate hull(PH-M),and chloroform extract of green tea(GT-C).Antioxidant activities above 1500 ppm was in the order of DTBP】BHT】GA】GT-C】GT-M】Q】PH-M.Synthetic antioxidants have been found more efficient to improve the storage stability of FAMEs obtained from hevea brasiliensis.DTBP in particular has the highest protection factor.
基金The authors thank Jana Zeleňáková(RIAP Nitra)for meat quality analysis.Special thanks also go to Research Institute for the Biology of Farm Animals,Dummerstorf,Germany,for antioxidant stability analysis.
文摘Forty-two (42) finishing pigs (entire males—EM, surgical castrates—SC and gilts—G, each of 14)—progeny of Landracesows and Hampshire × Pietrain boars, were included in the trial. They were randomly divided into control and experimental groups(each of seven). Control groups were fed the standard diet without any supplement. Experimental groups received standard diet withthe same composition as control but with supplement of creatine monohydrate (CMH, 2.0 g/kg of feed) for 30 d prior to slaughter.Sex of pigs had significant effect (p < 0.05) on drip loss and tenderness of pork when EM showed higher drip loss than SC and lowertenderness compared to other two groups (4.71% vs. 3.80%, resp. 3.23 vs. 3.91 and 4.12). Creatine level in plasma was increased byCMH supplementation in 46% in EM, 43% in SC and 41% in G. Similarly, concentration of phosphocreatine (PCr) in muscleincreased in 84% in EM, 88% in SC and 83% in G, respectively. CMH also improved meat colour L* (50.03 vs. 48.88) and reduceddrip loss in both EM (5.24% vs. 4.18%) and G (4.48% vs. 3.60%). Higher tenderness and better oxidative stability of pork after CMHsupplementation was found in all three sexes.
基金This work was funded by Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)and Secretaria de Ciencia y Técnica(SECyT)-Universidad Nacional de Córdoba,Argentina.
文摘The increasing demand of natural food from consumers has limited the use of traditional methods to control the oxidation of lipids,such as synthetic antioxidants and hydrogenation.Besides,it has been reported that the use of enzymes is efficient to eliminate dissolved oxygen in foods such as vegetable oils.Laccase is a polyphenol oxidase and the reduction of oxygen to water is accompanied by the oxidation,typically,of a phenolic substrate.Laccase have become important,industrially relevant enzymes that can be used for a number of diverse applications such waste detoxification,textile dye transformation,food technologic uses,biosensor and analytical applications,bioethanol production,among others.The target of this study was to evaluate the effect of laccase enzyme from Trametes versicolor,on the oxidative stability of sesame,chia,peanut and sunflower oils,measured through the peroxide value(PV)and conjugated dienes(K232)and trienes(K270).The samples of oil with laccase showed higher PV,K232 and K270 than their corresponding controls,under the conditions evaluated(room temperature and 60◦C).The results suggest that fungal laccase has an unexpected pro-oxidant effect on vegetable oils,possibly promoted by products derived from the oxidation of phenols by enzymatic action.
文摘Flaxseed oil,a key source of plant-based ω-3α-linolenic acid,is susceptible to oxidation and hazardous substance formation during refining and storage.This study evaluated the effects of refining stages(crude,degumming,complete refining)on aldehydes,trans fatty acids,and oxidative stability in flaxseed oil.The results indicate that heat-pressed oil has dark color with high a*and b*values,but exhibits the relatively highest oxidative stability during the oxidation process.However,compared to cold-pressing,heat-pressing promotes the generation of three additional aldehydes,butenal,nonanal,and trans,trans-2,4-decadienal.Degumming optimizes the color of crude oil while maintaining α-linolenic acid.In contrast,complete refining(degumming,deacidification,bleaching,and deodorization)caused the loss of substantial carotenoids and polyphenols,and α-linolenic acid decreased by 3.48%–4.47%,as well as a large amount of production of trans fatty acids.In addition,complete refining not only leads to the formation of newborn acrolein and trans-2-nominal but also results in a significant increase in most aldehydes concentration.This study provides a reference for the processing of flaxseed oil when considering the formation of hazardous substances induced by the oxidation and isomerization of polyunsaturated fatty acids.
基金supported by the National Key Research and Development Program of China(2016YFD0500505)the National Nature Science Foundation of China (No.31272485)
文摘The aim of the present study was to investigate the effect of dietary supplementation with sugar cane extract(SCE) on meat quality and oxidative stability of Longissimus dorsi muscle in finishing pigs.Eighteen barrows(Duroc × Landrace × Jiaxing Black), with an average initial body weight of 62.1 ± 5.0 kg,were randomly allotted to 1 of 3 diets with 6 replicates per treatment for 42 days. The diets comprised a normal diet and the normal diets supplemented with 5 and 25 g/kg SCE. The results showed that SCE supplementation did not affect final body weight of finishing pigs. Dietary SCE supplementation significantly increased(P < 0.05) Longissimus dorsi muscle pH_(24 h),and tended to reduce(P < 0.1) and significantly decreased(P < 0.05) shear force, drip loss, myofiber cross sectional area and lactate dehydrogenase activity at 5 and 25 g/kg, respectively. Meanwhile, dietary SCE treatments significantly decreased(P < 0.05) malonaldehyde content and total superoxide dismutase activity in Longissimus dorsi muscle, and tended to reduce(P < 0.1) malonaldehyde content in serum. Altogether, these data indicate that SCE is an effective feed additive to improve pork meat quality, and the underlying mechanism may be partly due to the improved oxidative stability induced by dietary SCE supplementation.
基金supported by the National Natural Science Founda-tion of China(Grants No.31920103012 and 31901603)China Postdoc-toral Science Foundation(Grant No.2019M663386)the Science and Technology Project of Guangzhou City(Grant No.201903010049).
文摘Oxidative deterioration of vegetable oils is of great importance in the food industry.In China,vegetable oils produced via thermal pretreatment are popular owing to their strong oil flavor and enhanced yield.Here,we review:(i)the currently employed thermal treatment methods of oilseeds before oil extraction;(ii)effects of thermal treatments on the physicochemical properties,contents of minor lipid components,and oxidative stability of vegetable oils;and(iii)Maillard model systems that are related to oil and oilseed chemistry.Among the thermal pretreatment technologies,microwave and infrared radiations are promising,but these are not performed on the same large production scales as roasting.For most oilseeds,thermal treatments increase the yield of extracted oil and content of minor lipid compounds in the oil,such as polyphenols,tocopherols,and phytosterols.In addition,some Maillard reaction products(MRPs)generated by heating oilseeds have been extracted.The presence of both minor lipids and MRPs in the oil confers improved oxidative stability.However,the mechanism or relationship between thermal treatment and oxidative stability is yet to be clearly elucidated because vegetable oil oxidation is dependent on variables such as unsaturation,concentration and types of minor lipid components,MRPs,and the potential synergistic effects of these components.Recently,several Maillard reaction models related to thermally treated oilseeds have been established,suggesting that MRPs play a critical role during oxidation.However,comprehensive identification of antioxidants and the mechanism by which they inhibit oxidation are lacking.Future research can be performed to establish models that would help elucidate the antioxidative mechanisms of MRPs for more oilseeds.Using these models,it will be possible to predict the oil quality after processing,based on the presence of MRPs and oil chemistry.
基金This work was financially supported by the Fundamental Research Funds for the Central Universities(2021SCU12094)the College Students Innovation and Entrepreneurship Training Program(C2021117946).
文摘Fatliquor oxidation may give leather unpleasant odor,and excessive amounts of Cr(VI)and volatile organic com-pounds.The accurate evaluation and improvement of the oxidative stability of fatliquors are of great significance to high-quality leather manufacturing.We proposed a set of practical methods for evaluating the oxidative stability of fatliquors on the basis of oxidation induction time,change in iodine value(∆IV),and change in acid value(∆AV)under accelerated oxidation conditions(at 100°C with 10 L/h of air).Oxidation induction time is a highly sensitive marker for quantifying the oxidative stability of fatliquors,and∆IV and∆AV that are low cost and easy to operate are useful in evaluating the oxidative stability of fatliquors when the oxidation induction time is less than 22 h.The number of double bonds in fatliquors is an important factor affecting oxidative stability.The sulfation modification of fatliquors that greatly reduces double bonds and the addition of antioxidants,especially butylated hydroxyanisole and butylated hydroxytoluene,markedly improve oxidative stability of fatliquors.
基金the Indian Council of Medical Research(ICMR),Government of India for providing the Senior Research Fellowship(SRF)grant in favour of Miss Rubiya Rashid(3/1/2/124/2019-(Nut).
文摘Nanoemulsion systems were employed to encapsulate the orange peel extract obtained from conventional maceration and novel ultrasound assisted extraction technology.Different wall materials maltodextrin(MD),whey protein isolate(WPI)and complex maltodextrin and whey protein isolate(MD/WPI)(1:1)were used in order to enhance the nanoemulsion stability,protect the bioactive core from degradation and control the release of bioactive compounds.The freeze drying technology was then used to obtain powder encapsulates with encapsulation efficiency and loading capacity of MD,WPI and MD/WPI as 89.3,91.2,95.6%and 95.3,94.4 and 93.1%respectively which depicts that encapsulation has taken place properly.All emulsions obtained were in nanoscale range with average hydrodynamic diameter as 105.0,201.82,215.12 and 298.82 for primary W/O emulsion,MD,WPI and MD/WPI stabilised emulsions respectively.These encapsulates were then incorporated in soyabean and mustard oil at different concentration 100,200 and 300 ppm and compared with free extract and synthetic antioxidant BHT to enhance storage life by controlling the oxidative changes during accelerated shelf life storage at 60o C for 24 days.The results obtained concluded that nanoencapsulated extracts performed better in prevention of oxidative indices than the free extract.However,nanocapsules encapsulated by MD/WPI exhibited higher protection of oils during storage than the maltodextrin and whey protein isolate.
文摘During storage,olive oil may suffer degradation leading to an inferior quality level when purchased and consumed.Oxidative stability is one of the most important parameters for maintaining the quality of olive oil,which affects its acceptability and market value.The current methods of predicting the oxidative stability of edible oils are costly and time-consuming.The aim of the present research is to demonstrate the use of dielectric spectroscopy integrated with computer vision for determining the oxidative stability index(OSI)of olive oil.The most effective features were selected from the extracted dielectric and visual features for each olive oil sample.Three machine learning techniques were employed to process the raw data to develop an oxidative stability prediction algorithm,including artificial neural network(ANN),support vector machine(SVM)and multiple linear regression(MLR).The predictive models showed a great agreement with the results obtained by the Rancimat instrument that was used as a reference method.The best result for modelling the oxidative stability of olive oil was obtained using SVM technique with the R-value of 0.979.It can be concluded that this new approach may be utilized as a perfect replacement for quicker and cheaper assessment of olive oil oxidation.
基金supported by the Russian Science Foundation under grant(Project No.19-16-00113).
文摘Beeswax can be a good structuring agent for edible oleogels.There is controversy about its role in the oleogel oxidation processes.This study investigated the oxidative stability of oleogels and the impact of their composition and texture on this stability.Oleogels were created by structuring sunflower oil with beeswax or combinations of its fractions(6%w/w gelator).Preparative flash chromatography was used to obtain beeswax fractions,which had a diverse composition according to TLC and HPLS-ELSD(hydrocarbons,wax esters,free fatty acids,and alcohols).Different oxidation indices(PV,AV,CDV,TOTOX,volatile organic compounds)of oleogels were evaluated,as well as their textural properties(firmness and Young’s modulus)after 20 days of storage at 35◦C.Among the tested samples,unstructured sunflower oil demonstrated the highest oxidative stability.The sample based on hydrocarbons and monoesters was the most stable of the oleogels tested.Hexanal is the most common volatile organic molecule generated during the oxidation of sunflower oil.Oleogels have a more complex profile of volatile compounds,including ketones,alcohols,and terpenes.Beeswax based oleogel’s induction period was the shortest.The oxidation rate of oleogels and Young’s modulus(r2=0.9511,negative),as well as the concentration of free fatty acids(r2=0.8195,positive)had a strong correlations.The results show that oleogels structured with beeswax fractions could be beneficial in fat-containing products with improved oxidation resistance.
基金U.S.Department of Agriculture-Research,Education and Economics(Agricultural Research Service)for providing funding for this study(58-8030-1-006)。
文摘This study aims to enhance the oxidative stability of njangsa seed oil(NSO)through encapsulation by ionic gelation using sodium alginate(ALG)solely or in combination with Bambara groundnut protein isolate(BPI)as wall materials.The encapsulation efficiency(EE)and loading capacity of the microcapsules produced using ALG and ALG-BPI were 73.76 and 76.30%and 57.99 and 61.48%,respectively.Confocal microscopic analysis showed an even distribution of NSO within the ALG-BPI microcapsules,which was confirmed by FTIR analysis.The scanning electron microscopy(SEM)analysis revealed a rough and porous structure for ALG-NSO,which ex-plains the higher NSO released of 22.29 and 78.51%during simulated gastric and intestinal digestion,respec-tively compared to ALG-BPI-NSO.Higher melting and degradation temperatures were obtained for ALG-BPI-NSO(304.76℃)compared to ALG-NSO(286.94℃).The free fatty acid content,peroxide,p-anisidine,and thio-barbituric acid values of encapsulated NSO were lower than in the free oil throughout the 21-day study period,with NSO encapsulated in ALG-BPI showing higher improved oxidative stability than with alginate alone.The study provided valuable information on fabricating an alginate-Bambara groundnut protein isolate-based effective delivery system for NSO.
文摘Fatty acid composition and triacylglycerols(TAG)profile of chia seed oil were determined.The main fatty acids present in the tested oil wereα-linolenic acid(Ln,61.1%)>linoleic acid(L,16.6%)>palmitic acid(P,6.7%)>oleic acid(O,6.0%)>stearic acid(S,3.2%).Five major triacylglycerols in chia oil were LnLnLn,LnLLn,LnLnP,LnOLn,and LLLn and these contributed more than 76%to the total.The oxidative stability under autoxidative and photooxidative conditions before and after the removal of their minor components was also determined.In addition,tocols,chlorophylls and carotenoids were measured in the oil.Oil samples were stripped of their minor components by using a facile silicic acid and charcoal in one pot rather than in a column.Storage under Schaal oven condition and photooxidation were also monitored for both crude oil(non-stripped)and stripped oil using stationary phase material.Total tocopherol contents were in the order ofβ−/γ-282.68,δ-47.44,andα-tocopherols 10.94 mg/kg of oil.Stripping removed all the minor components including tocopherols,chlorophylls and carotenoids.Oxidative stability of the tested seed oil was primarily affected by its composition of fatty acids,triacylglycerols,minor components,and storage conditions.
基金financially supported by the National Natural Science Foundation of China (No. 21774006)
文摘The sulfonated poly(α-methyl styrene-b-isobutylene-b-α-methyl styrene)copolymers(S-ASIBS)with the average molar percentage of sulfonic acid(-SO_(3)H)groups(SP)ranging from 3.6 mol%to 14.3 mol%could be synthesized by sulfonation of ASIBS with acetyl sulfate.The hydrophilic ionic channels were generated for proton exchange membranes(PEMs)by ion aggregation of-SO_(3)H groups and microphase separation between hydrophobic polyisobutylene and hydrophilic sulfonated poly(α-methyl styrene)segments in S-ASIBS.The proton transport ability was improved while oxidative stability was decreased by increasing SP in S-ASIBS.The appropriate SP of about 12.7 mol%in S-ASIBS provides the available PEMs with high proton transport ability,low methanol permeability and good oxidative stability.The absence of active tertiary hydrogen atoms along S-ASIBS copolymer chains avoids their attack by peroxy radicals.The residual rates of weight(RW)and proton conductivity(Rσ)of S-ASIBS-12.7 membrane after oxidation treatment for 916 h were 84.3%and 88.1%respectively,near to those of commercial Nafion 117(RW=87.9%,Rσ=90.3%).The membrane electrode assembly(MEA)could be prepared by using various S-ASIBS as PEMs for direct methanol fuel cell.The single cell with S-ASIBS-12.7 MEA behaves high performance of open circuit voltage(OCV)of 548 mV and peak power density(Pmax)of 36.1 mW·cm^(-2),which is similar to those of Nafion 117(OCV=506 mV,P_(max)=35.6 mW·cm^(-2)).To the best of our knowledge,this is the first example of advanced S-ASIBS membrane with high proton conductivity,excellent fuel barrier property and remarkable oxidative stability for promising PEMs.
文摘The oxidative and physical stability of the reformulated mayonnaise with processed beetroot was investigated and compared with a control(mayonnaise without beetroot)and a commercially available product.Processing of beetroot had an impact on the structural integrity of the antioxidants present.Microwaving(960 W for 7 min)was advantageous for preserving the betalain and polyphenol content of beetroot compared to roasting(180◦C for 90 min)and boiling(100◦C for 30 min).The oxidative stability of mayonnaise samples was determined by Rancimat and the thiobarbituric(TBA)assay.The addition of microwaved beetroot significantly enhanced the oxidative stability of mayonnaise at the end of a storage period of 4 weeks(4◦C).Although no significant differences(P>0.05)were detected between the mayonnaise samples containing beetroot and the commercial control,the latter was less susceptible to oxidation during storage.The turbiscan stability index(TSI)revealed that the commercial mayonnaise was less prone to destabilization phenomena.All the textural parameters increased with the incorporation of beetroot.The sensory evaluation revealed that,with the exception of graininess and uniformity,most of the sensory attributes are preserved if not improved with the addition of beetroot.
