KMITL
Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/kmitl/1
Browse
2 results
Search Results
- Some of the metrics are blocked by yourconsent settings
Item type:Publication, Volatile profiles and aroma-active components of Northern Thai fermented soybean (thua nao) produced from controlled and uncontrolled fermentations(2023-09-01) ;Mathatheeranan, Pakavit; ;Na Nan, Tansiphorn; Wang, YiThua nao is a fermented soybean product that is widely consumed, especially in the northern part of Thailand. Thua nao can be used as a condiment to enhance the aroma and flavor of foods. In general, commercial thua nao is traditionally made by indigenous microbial, especially Bacillus spp. fermentation under ambient conditions, leading to inconsistencies in product aroma quality. To solve this problem, inoculation of selected microorganisms can help control thua nao consistency. The objective of this research was to characterize and compare volatile aroma-active compounds in three samples, including thua nao made by commercial Bacillus subtilis inoculation fermented under controlled conditions (YSB) and two thua nao products made by indigenous fermentation in commercial production sites in Lumpoon (LPN) and Chiang-Mai (CMI) provinces, Thailand. It was found that 2-methyl butanoic acid, phenylethyl alcohol, benzaldehyde, 2,5-dimethylpyrazine, 2,6-dimethylpyrazine and 2-methoxy phenol were dominant compounds in the YSB samples. These compounds contributed to fermented/sour, floral, almond-like and nutty aromas, which were related to positive attributes perceived by consumers. In contrast, several aldehydes and ketones related to off-aroma as oxidized, fatty, green, and earthy attributes derived from lipid oxidations were dominantly detected in samples from uncontrolled fermentations (LPN and CMI). From the study, it can be implied that inoculation of B. subtilis in thua nao fermentation could enhance aroma compounds with positive attributes and thus improve the organoleptic property of the product. These findings could benefit fermented soybean manufacturers to improve their aroma quality and to control products’ consistency by controlling fermentation conditions. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, β-glucosidase producing Bacillus isolated from Thua-nao, an indigenous fermented soybean food in Thailand(2017-10-01) ;Meannui, Nutwara ;Riebroy, Siriporn; ;Hong, Jeong HwaSumpavapol, PunnaneeThe characteristics of commercial dried flatten Thua-nao collected from Northern of Thailand, namely oven dried (LPO) and sun dried (LPS) samples from Lamphun, sun dried sample from Chiang Mai (CMS) and sun dried sample from Chiang Rai (CRS),were investigated. The variations of chemical and physical characteristics were found among these Thua-nao products. Seventeen isolates of spore-forming bacteria were obtained from such products. Among these, four isolates (LPO-2, LPO-4, LPS-2 and CMS-1) were identified as Bacillus subtilis group by API 50CHB kit. For cellulolytic enzyme production, CMS-1 exhibited the highest clear zone on tryptic soy agar supplemented with carboxymethyl cellulose (P<0.05). Contrastingly, LPO-2 had the highest β-glucosidase activity with the lowest clear zone of cellulolytic enzyme activity (P<0.05). From 16S rRNA gene sequencing result, LPO-2 could be identified as Bacillus sp. and closely related to B. subtilis group.
