Flavor improvement of fermented soy sauce by extrusion as soybean meal pretreatment

Abstract

Flavor, an important index of soy sauce quality, includes odor and taste which mainly depend on volatile compounds and amino acids. Soy sauce made from extruded mixture of soy meal and flour (EMSF) was employed in fermentation to improve the flavor of final product. Combination of Headspace solid phase microextraction (HS‐SPME) and GC‐MS was employed to identify the volatile compounds, 40 volatile compounds were identified in soy sauce made from EMSF and 24 volatile compounds in soy sauce made form cooked mixture of soy meal and flour (CMSF). Pyrazines and their derivatives occupied one‐third of the total content of volatile compounds. Both samples had the same amino acid number, while total content of amino acids and contents of 15 kinds of amino acids in soy sauce made from EMSF were significantly higher than CMSF. Practical applications Extrusion had the advantage in low cost and capability of continuous processing, extruded mixture of soy meal and flour were used in soy sauce fermentation. Content of amino acids was improved by extrusion, this pretreatment method also increased volatile compounds of soy sauce and produced more desirable flavor and taste soy sauce.

Assessment the flavor of soybean meal hydrolyzed with Alcalase enzyme under different hydrolysis conditions by E-nose, E-tongue and HS-SPME-GC–MS

“…The analysis method was performed as described previously ( Zhang, He, Cao, Ma & Li 2017 ) with minor modifications. Three mL of soybean meal hydrolysate was accurately measured and placed in a 20 mL pre-balanced headspace bottle at 60 °C for 30 min.…”

Black rice addition prompted the beer quality by the extrusion as pretreatment

“…Extrusion processing is used widely for the improvement or modification of the food material qualities (Dale, Young, & Makinde, 2013;Zhang, He, Cao, Ma, & Li, 2017). During extrusion, starch gelatinization is performed at higher pressures and temperatures and also contributes to the breakdown of starch by mechanical shear force (Singh & Smith, 1997).…”

Partial substitution of wheat flour with soybean and gluten powder: impact on flavor characteristics of Pixian Douban‐Meju and its quality

“…Furthermore, acids, ketones, phenols, and furans have a significant effect on the flavor of PXDB. Recent studies have also illustrated that pyrazines and phenolics play an important role in fermented soy products 40,41 …”