Formation of Volatile Compounds DuringBacillus subtilis Fermentation of Soya Beans

Characterization of Volatile and Semi-Volatile Compounds in Chinese Rice Wines by Headspace Solid Phase Microextraction Followed by Gas Chromatography-Mass Spectrometry

“…As a result of the cooking process, furans are formed by thermal degradation and rearrangement of carbohydrates and proteins in non-enzymatic browning reactions (Maillard reaction) 5 . Similar to the furans, six nitrogen-containing compounds were detected in this study, most of which were identified in Chinese rice wine for the first time, and these could be formed through both non-enzymatic and enzymatic pathways 21,24 . In addition, three lactones were detected in the rice wines, and γ-butyrolactone and γ-nonalactone appeared in most rice wines.…”

Bacillus Fermentation of Soybean: A Review

“…The major components of these volatiles are 3-hydroxybutanone (acetoin), 2-methylbutanoic acid, pyrazines, and dimethyl sulfides together with other aromatic compounds. Similarly, Owens et al, (1997) reported that under anaerobic condition B. subtilis secretes á-acetolate which is decarboxylated by á-acetolate decarboxylase (extra cellular enzyme) to acetoine. Acetoine is then oxidised to diacetyl which is an aromatic compound linked in to flavour of many foods, such as yogurt.…”

“…Acetoine is then oxidised to diacetyl which is an aromatic compound linked in to flavour of many foods, such as yogurt. Production of ketone compounds is due to degradation of soy lipids and amino acids (Owens et al, 1997). Owens et al, (1997) listed changes in a number of aliphatic compounds; aliphatic aldehydes; aliphatic ketones; aliphatic acids and esters; pyrazines; furans; sulphur compounds; aromatic compounds; and other miscellaneous compounds during the B. subtilis fermentation.…”

“…Production of ketone compounds is due to degradation of soy lipids and amino acids (Owens et al, 1997). Owens et al, (1997) listed changes in a number of aliphatic compounds; aliphatic aldehydes; aliphatic ketones; aliphatic acids and esters; pyrazines; furans; sulphur compounds; aromatic compounds; and other miscellaneous compounds during the B. subtilis fermentation. In particular, concentration of pyrazines compounds increase well above their initial level which contributing significantly to the aroma of fermented soybeans.…”

“…However, drying of Thua-Nao drastically lower the concentration of volatile compounds in commercial Nao (fermented soybeans), reducing level of aliphatic acids, esters and sulphur compounds, but enhancing hexanol and trimetylpyrazine level. The loss of volatile compounds can be minimized by improving drying method or by alternative of preservation method (Owens et al, 1997).…”