Fermentation of green coffee beans is a promising method for enhancing coffee quality.However,to maintain the consistency of the coffee produced,a controlled and consistent process is required using a fermenter(fermen...Fermentation of green coffee beans is a promising method for enhancing coffee quality.However,to maintain the consistency of the coffee produced,a controlled and consistent process is required using a fermenter(fermentation vessel).This study aimed to evaluate the effect of ohmic heating(oH)and fermentation duration on the properties of coffee beans(robusta variety).Experiments were performed by combining two factors:fermentation type(with and without oH)and fermentation duration(6,12,and 18 h).The results showed that the fermentation time significantly affected the pH value of the fermented liquid,total acidity of the coffee,coffee bean colour,and caffeine content.oH-assisted fermentation reduced the caffeine content and increased the total acidity of robusta coffee,with the 18-h treatment yielding the lowest caffeine content.Additionally,a sensory analysis using the Specialty Coffee Association of America method revealed that coffee produced using oH-assisted fermentation for 18 h resulted in a higher score of 82.75,classified as a specialty grade.This study suggests that oH-assisted fermentation could improve sensory quality and reduce caffeine content in robusta green coffee beans,making it suitable for people who are sensitive to caffeine.展开更多
The combined inoculation of yeast and lactic acid bacteria(LAB)is a promising approach to enhance microbial metabo-lism and the quality of fermented food products.In this study,we investigated the effects of simultane...The combined inoculation of yeast and lactic acid bacteria(LAB)is a promising approach to enhance microbial metabo-lism and the quality of fermented food products.In this study,we investigated the effects of simultaneous and sequential inoculation of LAB and yeast on coffee fermentation.Fermentations were conducted using single and combined protocols with P.fermentans YC5.2 and P.pentosaceus LPBF07.A temporal analysis utilizing Illumina high-throughput rRNA Gene Sequencing revealed a synergistic interaction between the two microbial groups.This positive synergy led to increased consumption of coffee pulp sugar and the production of metabolites,surpassing the results observed in single cultures and the spontaneous process.Furthermore,the combined inoculation processes demonstrated a more significant role in sup-pressing wild microbiota compared to single cultures.Notably,the sequential process emerged as particularly effective in promoting a more intricate aroma profile and elevated sensorial score,attributed to the formation of distinctive compounds such as benzeneacetaldehyde,1-hexanol,2-heptanol,benzyl alcohol and phenylethyl alcohol.These results suggest that implementing a sequential inoculation process could enable coffee farmers to standardize on-farm processing and produce high-value-added products.展开更多
Microbial metabolites produced during fermentation migrate into the coffee and can influence the decrease in seed viability and coffee quality.This study evaluated the effects of physiological changes in seed viabilit...Microbial metabolites produced during fermentation migrate into the coffee and can influence the decrease in seed viability and coffee quality.This study evaluated the effects of physiological changes in seed viability on the sensory quality of the beverage using starter cultures through self-induced anaerobic fermentation(SIAF)in Coffea arabica L.for natural and pulped coffee.The yeasts were monitored by real-time polymerase chain reaction(qPCR).High-performance liquid chromatography(HPLC)detected citric,malic,and succinic acids in all fermented coffees.Furthermore,lactic acid was mainly identified in those coffees processed by the SIAF method.Volatile compounds(40)were detected by gas chromatography-mass spectrometry(GC-MS).Alterations in physiological quality were identified,with decreased embryonic viability and cell membrane damage by tetrazolium and electrical conductivity tests.All fermented coffees obtained scores above 80 points.The Torulospora delbrueckii yeast got the best score(86.50)in pulped coffee,and the Candida parapsilosis yeast received the highest score(85.90)in the natural coffee using the SIAF method.The coffees were characterized by aromas and flavors of citrus,caramel,honey,chocolate,and chestnut.The coffee fermentation process with yeast inoculation affected the coffee bean viability but not the beverage’s sensory quality,indicating that the use of yeast starters by SIAF favors the production of specialty coffees with differentiated sensory characteristics.展开更多
Rudimentary food fermentation can be defined as a spontaneous process of conversion of food components through enzy-matic action.A great variety of fermented foods are produced using spontaneous approaches;however,coc...Rudimentary food fermentation can be defined as a spontaneous process of conversion of food components through enzy-matic action.A great variety of fermented foods are produced using spontaneous approaches;however,cocoa and coffee represent the most important agricultural commodities on international markets.As a manner to increase the efficiency of these processes,starter cultures have been developed and applied under field conditions.The selection process begins with the recovery of microbial strains from spontaneous fermentation through phenotypic and metabolic traits.Next,mutation-based breeding is used to develop and improve well-adapted starter cultures.With advances in synthetic biology,especially in the last decade,the development of robust cellular fabrications with high fermentative capacity has become easier-largely due to the development of genomic approaches,such as next-generation sequencing techniques,CRISPR-Cas system and bioinformatics tools.This review brings prospects on the use of synthetic biology to design new robust strains for use in cocoa and coffee fermentations,but which can be extended to other rudimentary foods.In addition,metabolic traits and target genes(e.g.,UvrA,RecA,GPD1,and GPP2)are proposed as a starting point for the improvement of cocoa and coffee starters.Finally,the regulatory and safety requirements for these food crops are addressed.This review aims to stimulate research on the process of fermentation and the associated synthetic biology tools to produce fermented food efficiently and sustainably.展开更多
基金supported by Research Organization for Agriculture and Food,National Research and Innovation Agency-Indonesia under the Appropriate Technology Development Program Home(B-2172/III.11/PR.03.08/9/2022).
文摘Fermentation of green coffee beans is a promising method for enhancing coffee quality.However,to maintain the consistency of the coffee produced,a controlled and consistent process is required using a fermenter(fermentation vessel).This study aimed to evaluate the effect of ohmic heating(oH)and fermentation duration on the properties of coffee beans(robusta variety).Experiments were performed by combining two factors:fermentation type(with and without oH)and fermentation duration(6,12,and 18 h).The results showed that the fermentation time significantly affected the pH value of the fermented liquid,total acidity of the coffee,coffee bean colour,and caffeine content.oH-assisted fermentation reduced the caffeine content and increased the total acidity of robusta coffee,with the 18-h treatment yielding the lowest caffeine content.Additionally,a sensory analysis using the Specialty Coffee Association of America method revealed that coffee produced using oH-assisted fermentation for 18 h resulted in a higher score of 82.75,classified as a specialty grade.This study suggests that oH-assisted fermentation could improve sensory quality and reduce caffeine content in robusta green coffee beans,making it suitable for people who are sensitive to caffeine.
基金funded by the National Council for Scientific and Technological Development,CNPq,grant nos.440343/2022-4 and 306421/2020-8.
文摘The combined inoculation of yeast and lactic acid bacteria(LAB)is a promising approach to enhance microbial metabo-lism and the quality of fermented food products.In this study,we investigated the effects of simultaneous and sequential inoculation of LAB and yeast on coffee fermentation.Fermentations were conducted using single and combined protocols with P.fermentans YC5.2 and P.pentosaceus LPBF07.A temporal analysis utilizing Illumina high-throughput rRNA Gene Sequencing revealed a synergistic interaction between the two microbial groups.This positive synergy led to increased consumption of coffee pulp sugar and the production of metabolites,surpassing the results observed in single cultures and the spontaneous process.Furthermore,the combined inoculation processes demonstrated a more significant role in sup-pressing wild microbiota compared to single cultures.Notably,the sequential process emerged as particularly effective in promoting a more intricate aroma profile and elevated sensorial score,attributed to the formation of distinctive compounds such as benzeneacetaldehyde,1-hexanol,2-heptanol,benzyl alcohol and phenylethyl alcohol.These results suggest that implementing a sequential inoculation process could enable coffee farmers to standardize on-farm processing and produce high-value-added products.
文摘Microbial metabolites produced during fermentation migrate into the coffee and can influence the decrease in seed viability and coffee quality.This study evaluated the effects of physiological changes in seed viability on the sensory quality of the beverage using starter cultures through self-induced anaerobic fermentation(SIAF)in Coffea arabica L.for natural and pulped coffee.The yeasts were monitored by real-time polymerase chain reaction(qPCR).High-performance liquid chromatography(HPLC)detected citric,malic,and succinic acids in all fermented coffees.Furthermore,lactic acid was mainly identified in those coffees processed by the SIAF method.Volatile compounds(40)were detected by gas chromatography-mass spectrometry(GC-MS).Alterations in physiological quality were identified,with decreased embryonic viability and cell membrane damage by tetrazolium and electrical conductivity tests.All fermented coffees obtained scores above 80 points.The Torulospora delbrueckii yeast got the best score(86.50)in pulped coffee,and the Candida parapsilosis yeast received the highest score(85.90)in the natural coffee using the SIAF method.The coffees were characterized by aromas and flavors of citrus,caramel,honey,chocolate,and chestnut.The coffee fermentation process with yeast inoculation affected the coffee bean viability but not the beverage’s sensory quality,indicating that the use of yeast starters by SIAF favors the production of specialty coffees with differentiated sensory characteristics.
基金funded by Conselho Nacional de Desenvolvimento Científico e Tecnológico,306421/2020-8.
文摘Rudimentary food fermentation can be defined as a spontaneous process of conversion of food components through enzy-matic action.A great variety of fermented foods are produced using spontaneous approaches;however,cocoa and coffee represent the most important agricultural commodities on international markets.As a manner to increase the efficiency of these processes,starter cultures have been developed and applied under field conditions.The selection process begins with the recovery of microbial strains from spontaneous fermentation through phenotypic and metabolic traits.Next,mutation-based breeding is used to develop and improve well-adapted starter cultures.With advances in synthetic biology,especially in the last decade,the development of robust cellular fabrications with high fermentative capacity has become easier-largely due to the development of genomic approaches,such as next-generation sequencing techniques,CRISPR-Cas system and bioinformatics tools.This review brings prospects on the use of synthetic biology to design new robust strains for use in cocoa and coffee fermentations,but which can be extended to other rudimentary foods.In addition,metabolic traits and target genes(e.g.,UvrA,RecA,GPD1,and GPP2)are proposed as a starting point for the improvement of cocoa and coffee starters.Finally,the regulatory and safety requirements for these food crops are addressed.This review aims to stimulate research on the process of fermentation and the associated synthetic biology tools to produce fermented food efficiently and sustainably.
