Use of Pseudocereals Preferment Made with Aromatic Yeast Strains for Enhancing Wheat Bread Quality

Abstract

Usually, aromatic yeasts are designed to ferment wheat substrates for baking purposes but identification of new substrates for these strains and consequently new formulations for dough could lead to diversified bakery products with improved nutritional qualities and specific sensorial properties. The purpose of our study was to optimize the fermentation of quinoa and amaranth flours with non-conventional yeast strains in order to obtain a preferment with high potential in enhancing nutritional, textural and sensorial features of white wheat bread. Two biotypes of Saccharomyces cerevisiae yeast-a wine yeast strain and a beer yeast strain-commercialized for their aromatic properties were used. Both aromatic yeast strains revealed good performance on fermenting pseudocereal substrates. Utilization of the obtained preferment in white wheat breadmaking led to bread with higher protein, fibres, mineral, total polyphenols content, with specific texture and aroma profile and high consumers' acceptability.

Keywords: aromatic yeast; preferment; quinoa; wheat bread.

Figure 1

pH and total titratable acidity (TTA,%) variations (A), yeast counts (B) for preferment samples during fermentation period and carbohydrates conversion and ethanol formation after 18h of fermentation in pseudo-cereals preferment by aromatic yeast strains (C) (T1- sampling time before inoculation; T2- sampling time after 18h of fermentation. All determinations were performed in triplicate; For details, see Materials and methods; Each sample code is explained by sample name in Table 1).