This study aimed to produce and investigate Ale-type barley-spelt beers with low-alcohol levels by utilizing two different non-Saccharomyces yeasts,Torulaspora delbrueckii and Saccharomycodes ludwigii,and compare them...This study aimed to produce and investigate Ale-type barley-spelt beers with low-alcohol levels by utilizing two different non-Saccharomyces yeasts,Torulaspora delbrueckii and Saccharomycodes ludwigii,and compare them to Ale-beers fermented with commercial Ale-yeast(Saccharomyces cerevisiae).The effects of both primary and bottle fermentation on sugar utilization,ethanol yield,and volatile compound profiles were examined.Volatile compound profile and contents were determined after primary and bottle fermentations with GC-MS.Wort contained high initial levels of maltose(62.5 g/L),maltotriose(42.3 g/L),fructose(22.0 g/L),and sucrose(17.9 g/L).Fermentation with S.cerevisiae resulted in extensive sugar consumption,leaving only small amounts of maltose,maltotriose and fructose.By contrast,T.delbrueckii and S.ludwigii retained most of the maltose and maltotriose,but no fructose was detected.S.cerevisiae produced the highest ethanol concentrations(3.39%v/v),whereas T.delbrueckii and S.ludwigii yielded significantly lower levels(1.24%v/v and<1.0%v/v,respectively).S.cerevisiae increased the contents of many volatile compounds after both fermentation types,while only a few volatile compounds were detected in significant quantities in the non-Saccharomyces fermen-tations.Furthermore,non-Saccharomyces fermentations generated higher sulfur compound levels that could impact beer aging.In conclusion,S.cerevisiae demon-strated high efficiency in sugar assimilation and ethanol formation,while T.delbrueckii and S.ludwigii showed limited fermentation performance,indicating their potential in producing low-alcohol beers with potentially distinct and milder sensory properties.展开更多
Saccharomycodes ludwigii is a wine-related non-Saccharomyces yeast known for releasing significant amounts of polysaccharides that contribute to reduced wine haziness and enhanced mouthfeel and colloidal stability.Thi...Saccharomycodes ludwigii is a wine-related non-Saccharomyces yeast known for releasing significant amounts of polysaccharides that contribute to reduced wine haziness and enhanced mouthfeel and colloidal stability.This study focuses on the production and characterization of yeast derivatives from S.ludwigii strain SL#64.Pilot-scale biomass production was optimized in fed-batch mode by maintaining a specific growth rate of 0.073 h^(-1),below the critical threshold,thereby ensuring respiratory metabolism and minimizing ethanol formation,supporting the hypothesis of a Crabtree-positive behaviour in S.ludwigii.Biomass was subjected to six inacti-vation treatments:thermal inactivation(TI),partial lysis(PL),total lysis(TL),high-pressure processing(HPP),microfluidics(MF),and combined PL+HPP.These produced derivatives with distinct compositional profiles showing nitrogen contents of 0.2-0.6%,total fatty acid of 5.4-6.1%,and polysaccharides ranging from 27.1%to 30.9%.Their technological impact was assessed in laboratory-scale fermentations of Glera grape must with Saccharomyces cerevisiae,using a commercial yeast derivative as reference.The addition of 35 g/hL of each SL#64 derivative enhanced S.cerevisiae growth and fermentation kinetics,with TL showing the strongest effect on fermentation performance(12.74%ethanol and 10.70 g/L of residual sugars).The inactivation technique significantly influenced polysaccharide concentration(174.93 to 255.73 mg/L)and shaped the aromatic profile of the resulting wines.Overall,S.ludwigii may be proposed as a workhorse for the production of customized yeast derivatives with multifunctional applications in winemaking.展开更多
基金funded by the Southwestern Finland Regional Funds of the Finnish Cultural Foundation(85222197).
文摘This study aimed to produce and investigate Ale-type barley-spelt beers with low-alcohol levels by utilizing two different non-Saccharomyces yeasts,Torulaspora delbrueckii and Saccharomycodes ludwigii,and compare them to Ale-beers fermented with commercial Ale-yeast(Saccharomyces cerevisiae).The effects of both primary and bottle fermentation on sugar utilization,ethanol yield,and volatile compound profiles were examined.Volatile compound profile and contents were determined after primary and bottle fermentations with GC-MS.Wort contained high initial levels of maltose(62.5 g/L),maltotriose(42.3 g/L),fructose(22.0 g/L),and sucrose(17.9 g/L).Fermentation with S.cerevisiae resulted in extensive sugar consumption,leaving only small amounts of maltose,maltotriose and fructose.By contrast,T.delbrueckii and S.ludwigii retained most of the maltose and maltotriose,but no fructose was detected.S.cerevisiae produced the highest ethanol concentrations(3.39%v/v),whereas T.delbrueckii and S.ludwigii yielded significantly lower levels(1.24%v/v and<1.0%v/v,respectively).S.cerevisiae increased the contents of many volatile compounds after both fermentation types,while only a few volatile compounds were detected in significant quantities in the non-Saccharomyces fermen-tations.Furthermore,non-Saccharomyces fermentations generated higher sulfur compound levels that could impact beer aging.In conclusion,S.cerevisiae demon-strated high efficiency in sugar assimilation and ethanol formation,while T.delbrueckii and S.ludwigii showed limited fermentation performance,indicating their potential in producing low-alcohol beers with potentially distinct and milder sensory properties.
基金P.D.acknowledges the contribution of Enartis srl,(Via S.Cassiano 99,28069 Trecate,Italy)to the development of this work.
文摘Saccharomycodes ludwigii is a wine-related non-Saccharomyces yeast known for releasing significant amounts of polysaccharides that contribute to reduced wine haziness and enhanced mouthfeel and colloidal stability.This study focuses on the production and characterization of yeast derivatives from S.ludwigii strain SL#64.Pilot-scale biomass production was optimized in fed-batch mode by maintaining a specific growth rate of 0.073 h^(-1),below the critical threshold,thereby ensuring respiratory metabolism and minimizing ethanol formation,supporting the hypothesis of a Crabtree-positive behaviour in S.ludwigii.Biomass was subjected to six inacti-vation treatments:thermal inactivation(TI),partial lysis(PL),total lysis(TL),high-pressure processing(HPP),microfluidics(MF),and combined PL+HPP.These produced derivatives with distinct compositional profiles showing nitrogen contents of 0.2-0.6%,total fatty acid of 5.4-6.1%,and polysaccharides ranging from 27.1%to 30.9%.Their technological impact was assessed in laboratory-scale fermentations of Glera grape must with Saccharomyces cerevisiae,using a commercial yeast derivative as reference.The addition of 35 g/hL of each SL#64 derivative enhanced S.cerevisiae growth and fermentation kinetics,with TL showing the strongest effect on fermentation performance(12.74%ethanol and 10.70 g/L of residual sugars).The inactivation technique significantly influenced polysaccharide concentration(174.93 to 255.73 mg/L)and shaped the aromatic profile of the resulting wines.Overall,S.ludwigii may be proposed as a workhorse for the production of customized yeast derivatives with multifunctional applications in winemaking.
