Effect of Novel Starter Culture on Reduction of Biogenic Amines, Quality Improvement, and Sensory Properties of Doenjang, a Traditional Korean Soybean Fermented Sauce Variety

Abstract

To select appropriate microorganisms as starter cultures for the reliable and reproducible fermentation of soybean fermented products of Korean Doenjang, various ratios of fungi (Aspergillus oryzae J, Mucor racemosus 15, M. racemosus 42) combined with Bacillus subtilis TKSP 24 were selected as either single, double, or multiple Meju strains for commercial mass production of Doenjang, followed by analysis of sensory characteristics. In the sensory evaluation, Doenjang BAM15-1 and BAM42-1, which were fermented with multiple strains (1:1:1), showed the highest sensory scores as compared to control. Based on sensory characteristics, 6 Doenjang samples were subjected to quantitative determination of amino acids, free sugars, and organic acids (volatile and nonvolatile) contents, followed by determination of biogenic amines. Total sweet taste amino acid contents were highest in BAM15-1 and BAM42-1 samples (333.7 and 295.8 mg/100 g, respectively) and similar that of control (391.1 mg/100 g). Samples BAM15-1 and BAM42-1 showed the relatively high volatile and nonvolatile organic acid contents (154.24, 192.26, and 71.31, 82.42 mg/100 g, respectively). In addition, BAM15-1 and BAM42-1 showed negligible biogenic amine formation, ranging from 0.00 to 1.02 and 0.00 to 3.92 mg/100 g, respectively. These findings indicate that determination of food components along with sensory and quality attributes using multiple microbial Meju strains as a starter culture may provide substantial results on improved quality fermented Doenjang products.

Development of Safe and Flavor‐Rich Doenjang (Korean Fermented Soybean Paste) Using Autochthonous Mixed Starters at the Pilot Plant Scale

“…The a * value (redness) increased during the fermentation progressed, but the b * value (yellowness) changed little over the aging period. Overall, the changes in a * and b * values were insignificant and this tendency was in agreement with previous studies Shukla et al, 2015).…”

“…The L value (lightness) generally decreased during doenjang aging, and the 4 week samples showed a very dark color. In general, lightness decreases during doenjang aging, especially in traditional doenjang (Lee et al., ; Shukla et al., ). The a * value (redness) increased during the fermentation progressed, but the b * value (yellowness) changed little over the aging period.…”

Bioavailability of Isoflavone Metabolites After Korean Fermented Soybean Paste (Doenjang) Ingestion in Estrogen‐Deficient Rats

“…Natural microorganisms such as Bacillus subtillis , Rhizopus spp., and Aspergillus spp. are involved in the fermentation process (Shukla et al., ). Several studies on the functionality of DJ have revealed anti‐obesity, anti‐diabetic, antioxidant, and anti‐inflammatory effects (Kwak, Son, Chung, & Kwon, ; Kwon, Daily, Kim, & Park, ; Nam, Won, Chung, Kwak, & Kwon, ).…”

Evaluation of fungal microflora for aflatoxin producing possibility in novel quality Meju fermented with single and/or multiple additions of Nelumbo nucifera, Ginkgo biloba, and Allium sativum extracts

“…In Korea, there are several traditional fermented soybean products with the most common being Chungkukjang , Doenjang , Kochujang , and soy sauce. These soybean‐based products are traditionally fermented using various natural microflora such as Bacillus subtilis , Aspergillus oryzae ( A. oryzae ), and Mucor racemosus ( M. racemosus ), although microorganisms in the environment can vary (Shukla, Lee, Park, Kim, & Kim, ). For the production of soybean fermented products by traditional methods, cooked soybeans are formed into bricks and fermented outdoors for 30–45 days in a natural environment.…”