Free amino acids identification and process optimization in greengage wine fermentation and flavor formation

Abstract

Greengage wine with low alcohol content is increasing in popularity owing to its fruity taste and rich nutrition. The key to wine aroma and taste is flavor substances like free amino acids (FAAs), volatile fatty acids, higher alcohols, and esters. Amino acid (AA) metabolisms in yeast are an important source of these secondary compounds, which vary with the fermentation conditions. This study explored and optimized the impact of different parameters (carbon source, inoculum, pH, temperature) on FAA contents and dynamics in greengage wine. The results demonstrated that total and essential amino acid (EAA) content rose with a higher proportion of glucose, less yeast inoculation, higher temperature, and higher initial pH. With the results obtained it was concluded that the condition of 22.4°C, pH 4.5, and 3% inoculation was optimum for a 14.9‐fold increase of EAAs in fermented greengage wine. In the long run, the research will aid in the development of the greengage brewing industry.

Contribution of Saccharomyces and Non-Saccharomyces Yeasts on the Volatile and Phenolic Profiles of Rosehip Mead

“…These findings support previous work [58], which reported that the composition of amino acids affects the formation of volatile compounds that contribute to the aroma of fermented beverages. Moreover, Yan et al [59], emphasized that amino acid composition and prevalence play a paramount role in understanding flavor and taste formation, as they act as crucial precursors for synthesizing volatile compounds that contribute to aroma and taste perception. Based on their taste characteristics, amino acids can be classified as follows: sweet amino acids including glycine (Gly), serine (Ser), alanine (Ala), proline (Pro), threonine (Thr), cysteine (Cys), and methionine (Met); bitter amino acids such as arginine (Arg), histidine (His), isoleucine (Ile), leucine (Leu), phenylalanine (Phe), lysine (Lys), tyrosine (Tyr), and valine (Val); and umami amino acids namely aspartic acid (Asp) and glutamic acid (Glu) [60,61].…”