Yeast Strain and Kinetic Aspects of the Formation of Flavour Components in Cider

Abstract

An apple juice was fermented at 8°C using twelve strains of Saccharomyces uvarum. Glucose, fructose, malic and L-lactic adds, isobutanol, 2,3 butanediol, isoamyl alcohol, ethyl acetate and titratable acidity were determined and monitored in the course of fermentation. It was observed that yeast strains differed from one another mainly In fermentation rates. When components were determined in ciders of the same remaining fructose concentration, rather than after the same fermentation time, the only significant effect of the yeast strain was on the amounts of glucose and ethanol in sweeter cider (fructose 34 g/IHre), or on the amounts of glucose, acetic add, isobutanol and amyl alcohols in dryer ciders (fructose 17 g/litre).A sensory analysis showed that standard deviations of concentrations of remaining or formed components in dders fermented by different yeast strains, was sufficient to be detected by the taste panel. Added glucose in this range of concentration (1.5 g/litre) in dder reduced the perception of sourness while the addition of acetic add (0.3 g/litre) reduced the perception of the scanted flavour. Added Isobutnol (6 mg/litre) reduced the perception of sweetness. No significant effect of added isoamyl alcohol (30 mg/litre) could be detected.Chemical determinations were correlated by means of regression equations derived from earlier work with some organoleptic characteristics. No anticipated effect of the yeast strain could be detected on any studied flavour characteristic. It is concluded that in ciders of the same attenuation, the effect if ft does exist, of the S.uvarum strain isolated from ciders, must be low.

Aroma formation by immobilized yeast cells in fermentation processes

“…Buron et al () performed an extensive investigation for the screening of representative cider yeasts and bacteria (47 yeast strains and 16 bacterial strains) for volatile phenol‐production ability. Interestingly, when components were determined in ciders of the same remaining fructose concentration produced with 12 different yeast strains (70 day fermentations carried out at 8 °C), the only significant effect of the yeast strain was on the amounts of glucose and ethanol in sweeter cider (fructose 34 g/l), or on the amounts of glucose, acetic acid, isobutanol and amyl alcohols in dryer ciders (fructose 17 g/l) (Leguerinel et al, ). The trends in food fermentation are focused on the isolation of proper wild‐type strains from traditional products to be used as starter cultures, with the aim of conducting industrial production processes without losing their unique flavour and product characteristics.…”

The microbiology of alcoholic beverages

“…Fermentation leads to the production of mainly ethanol and a vast range of acids, higher alcohols, esters, aldehydes, ketones and sulphur volatiles which, with the fruit constituents, give cider its characteristic sensory quality. The final ethanol concentration in the product may range from 1.5 to 8.5%, depending on national legislation (Leguerinel et at., 1989;Jarvis et at., 1995;Lea, 1995).…”

Effect of Enzymatic Maceration on Synthesis of Higher Alcohols During Mango Wine Fermentation

“…Cider taste depends mainly on cultivar (Beech and Carr 1977), while cider odor depends more on the processing technology (Gomis et al. 1991) and yeast strain employed (Leguerinel et al. 1989).…”