Quantification of Biogenic Amines in 35 Korean Cottage Industry Traditional Gochujang (Fermented Red Pepper Paste) Products

Safety Analysis of Korean Cottage Industries' Doenjang, a Traditional Fermented Soybean Product: A Special Reference to Biogenic Amines

The typical Korean diet contains a significant quantity of doenjang owing to its unique taste and health benefits. However, the presence of anti-nutritional and toxic substances, such as biogenic amines and microbial pathogens, in doenjang has resulted in a loss of revenue and poor consumer health. The present study focused on the identification and quantification of different biogenic amines, pathogenic Bacillus cereus, and yeast counts in 36 doenjang products (designated as De-1 to De-36, 500 g each) procured from the different cottage industries situated in different parts of the Republic of Korea. The results indicated, only three samples were contaminated with B. cereus, exceeding the recommended limit (4 log CFU/g) suggested by the national standards of Korea. A total of six distinct yeasts were identified in different doenjang samples, whose comprehensive enzymatic profiling suggested the absence of harmful enzymes such as N-acetyl-β-glucosaminidase, α-chymotrypsin, and β-glucuronidase. The biogenic amines were detected in the range of 67.68 mg/kg to 2556.68 mg/kg and classified into six major groups based on hierarchical cluster analysis. All doenjang samples contained tryptamine, putrescine, cadaverine, histamine, and tyramine, while 94.44% were positive for spermidine and spermine. The results documented the analysis of traditional cottage industry doenjang and suggest the need for constant monitoring to ensure the safety of food for the consumer.

Correlation between the microbiome and pack burst spoilage of Allium sativum supplemented fermented hot pepper paste

Gochujang (fermented hot pepper paste) products are well known for their distinct, spicy flavor. However, frequent pack burst spoilage of gochujang products occurs during transportation and storage because of microbial aerogenesis, resulting in considerable economic losses. The present study aimed to prevent pack burst spoilage of gochujang products by supplementing them with garlic ethanol extract. A simulated pack burst experiment revealed that 42.86 % of normal gochujang products were spoiled. Garlic ethanol extract significantly inhibited the growth of Zygosaccharomyces rouxii in gochujang products, with low minimum inhibitory concentration values (12.5-25 mg/mL). Gochujang products supplemented with various concentrations (1 % and 2.5 %) of garlic ethanol extract exhibited marked inhibition of microbial growth, particularly Z. rouxii, and pack burst spoilage. Microbiome analysis revealed that the pack burst samples harbored a high abundance of Z. rouxii. Supplementation of gochujang with 1 % garlic ethanol extract drastically reduced Z. rouxii abundance and prevented pack burst. Moreover, gochujang products supplemented with 1 % garlic ethanol extract exhibited a high hedonic score in the sensory analysis. Based on the results of this study, we concluded that supplementation of gochujang products with 1 % garlic ethanol extract before packaging could be effective in preventing pack burst spoilage of gochujang.

Physicochemical, Microbial, and Volatile Compound Characteristics of Gochujang, Fermented Red Pepper Paste, Produced by Traditional Cottage Industries

Gochujang, fermented red pepper paste, is a grain-based Korean traditional food. The quality of gochujang produced by cottage industries is not well-documented. Thus, the present study aimed to analyze the quality of gochujang from 35 traditional cottage industries for physicochemical and microbial characteristics, along with volatile compound contents. In addition to microbial characteristics, salinity, pH, free amino nitrogen, and alcohol content were evaluated. Ethanol was detected as the predominant alcohol and 57% of tested gochujang products harbored >1% of total alcohol content, which was above the recommended level for halal products. Gochujang products contained hexadecanoic and linoleic acids predominantly and several volatile compounds belonging to the classes of alcohols, aldehydes, alkanes, nitrogen-containing compounds, and terpenes. A wide range of aerobic mesophilic bacteria (2.79–8.73 log CFU/g) and yeast counts (1.56–7.15 log CFU/g) was observed. Five distinct yeast species were identified, including Zygosaccharomyces rouxii. Eight gochujang products were found to be contaminated with Bacillus cereus (>4 log CFU/g). This study suggests that there is a need to limit B. cereus contamination in cottage industry products and reduce alcohol content to comply with halal food guidelines.