Quality of Kapi,Salted Shrimp Paste of Thailand,Inoculated with Bacillus spp. K-C3

The use of Bacillus spp. K-C3, isolated from commercial Kapi, salted shrimp paste of Thailand, as the starter culture for Kapi production, at different levels including 10², 10⁴, and 10⁶ CFU/g dry weight sample named Kapi-B2, Kapi-B4, and Kapi-B6, respectively, in comparison with naturally fermented Kapi (Kapi-C) was studied. All inoculated samples exhibited higher extent of proteolysis and lipolysis as indicated by higher trichloroacetic acid (TCA)-soluble peptide, degree of hydrolysis, and free fatty acid content in the final products. The greater rate of fermentation in the inoculated samples directly affected characteristics of Kapi and yielded Kapi with browner color and enhanced lipid oxidation as indicated by peroxide value (PV) and thiobarbituric acid reactive substance (TBARS) values. Increased antioxidative properties, including 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activities, and ferric reducing antioxidant power (FRAP), were obtained in Kapi with added inoculum. Moreover, those inoculated samples also contained higher intensity of volatile compounds, in which N-containing compounds, mainly pyrazine derivatives, were dominant. Kapi-B4 and Kapi-B6 showed the highest extent of these aforementioned values compared with Kapi-C and Kapi-B2. Therefore, inoculation with Bacillus spp. K-C3 at the level higher than 10⁴ CFU/g dry weight sample is a potential means to accelerate the fermentation rate and yielded Kapi with preferable characteristics.     

Combined Effect of Ethanolic Coconut Husk Extract and Modified Atmospheric Packaging (MAP) in Extending the Shelf Life of Asian Sea Bass Slices

Combined impact of ethanolic coconut husk extract (ECHE) (200 ppm) and modified atmosphere packaging (MAP) with two separate gas mixtures [60% CO₂/30% N₂/10% O₂ (M1) and 80% CO₂/10% N₂/10% O₂ (M2)] on the shelf life of Asian sea bass slices during 4°C storage was investigated. Microbial load of slices was lowered when packaged under MAP, regardless of ECHE treatment, compared to the control (no ECHE treatment, packed in air). For control, slices treated with ECHE packaged in air, and samples packaged under M1, TVBC (total viable bacteria count) exceeded 6.0 log CFU/g at day 6, 9, and 12, respectively. TVBC of samples treated with 200-ppm ECHE and packaged under M1 and those packaged under M2 without and with ECHE treatment were lower than 6.0 log CFU/g at day 15. Peroxide and thiobarbituric acid reactive substances values in samples treated with ECHE, regardless of the packaging method, were lower than those kept under MAP and the control. Thus, shelf life extension of Asian sea bass slices could be achieved by treatment with 200-ppm ECHE in combination with M1 packaging, in which they could be stored longer than 15 days at 4°C.     

Genetic diversity and structure of landrace of lablab (Lablab purpureus (L.) Sweet) cultivars in Thailand revealed by SSR markers

Lablab (Lablab purpureus (L.) Sweet) is a legume crop widely cultivated in tropical and subtropical regions of Africa and Asia. In this study, we assessed genetic diversity and population structure of 299 individuals of subspecies purpureus and bengalensis of lablab from Thailand using 13 simple sequence repeat (SSR) markers. The SSR markers detected only 34 alleles in total with a mean of 2.6 alleles per locus. Overall gene diversity was 0.360. Gene diversity (H_E) and allelic richness (A_R) in different geographic regions was comparable. Similarly, both H_E and A_R between subspecies purpureus and bengalensis were similar. STRUCTURE and neighbor-joining (NJ) analyses revealed that the 299 individuals were clustered into two major groups. In contrast, principal coordinate analysis (PCoA) revealed admixture of the lablab germplasm. STRUCTURE, NJ and PCoA analyses also revealed that the subspecies purpureus and bengalensis are not genetically differentiated. Although the number of individuals from the west of Thailand was small and all of them were collected from the same province, they possessed comparable gene diversity with those from the other geographic regions. These results demonstrated that there is moderately low genetic diversity of lablab in Thailand and the west of the country possesses high diversity of lablab.