No abstract

The processed drinks produced from grass of three varieties of rice (Jasmine, Sukhothai 1 and Sukhothai 2) and one each from wheat and barley grasses were analyzed for chlorophyll and total phenolic contents, and antioxidant activities [ABTS radical cation decolorisation assay and ferric reducing/antioxidative power (FRAP) assay]. The consumer acceptance of all the drinks was also evaluated. One serving size (200 mL) of these contained 82-958 μg of chlorophyll, 5.60-26.14 mg Gallic acid equivalent for total phenolic content and their antioxidant activities, ABTS and FRAP values were 17.88-35.18 mg Vitamin C equivalent and 5.66-23.70 mg FeSO equivalent, respectively. The overall consumer acceptability of drinks was significantly correlated to their aroma intensity and consumer preference on aroma and flavor. Jasmine and Sukhothai 1 rice grass drinks were most preferred, however, one subgroup preferred grass drink from Sukhothai 1 rice, while the second subgroup preferred the drinks from Sukhothai 2 rice and Jasmine rice. Wheat and barley grass drinks were not preferred by both subgroups.

L-glutaminase and glutamic acid decarboxylase (GAD) catalyzes the hydrolysis of L-glutamine and glutamate, respectively. L-glutaminase widely used in cancer therapy along with a combination of other enzymes and most importantly these enzymes were used in food industries, as a major catalyst of bioconversion. The current investigation was aimed to screen and select L-glutaminase, and GAD producing lactic acid bacteria (LAB). A total of 338 LAB were isolated from fermented meat, fermented fish, fermented soya bean, fermented vegetables and fruits. Among 338 isolates, 22 and 237 LAB has been found to be positive for L-glutaminase and GAD, respectively. We found that 30 days of incubation at 35 ºC and pH 6.0 was the optimum condition for glutaminase activity by G507/1. G254/2 was found to be the best for GAD activity with the optimum condition of pH 6.5, temperature 40 ºC and ten days of incubation. These LAB strains, G507/1 and G254/2, were identified as close relative of Lactobacillus brevis ATCC 14869 and Lactobacillus fermentum NBRC 3956, respectively by 16S rRNA sequencing. Further, improvements in up-stream of the fermentation process with these LAB strains are currently under development.Keywords: L-glutaminase; glutamic acid decarboxylase; lactic acid bacteria and 16S rRNA sequencing.Practical Application: LABs based safe starter culture for the fermentation of mushroom to produce high GABA.

Fermented plant beverages (FPB) with a high content of desirable principle components are served as functional foods from several years. Hericium erinaceus is famous for its antimicrobial, antioxidant, antihypertensive and antidiabetic nature. Accordingly, the current study was aimed to produce fermented H. erinaceus juice with a high content of L-glutamine (Gln) and L-glutamic acid (GA) through lactic acid bacteria (LAB) isolated from fermented Thai foods. LAB isolates were screened and identified the potent protease-producing bacteria Enterococcus faecalis (G414/1) that facilitate the production of Gln and GA through protein hydrolysis. Box-Behnken design (BBD) and response surface methodology (RSM) were adapted for the optimisation of conditions for the increased production of Gln and GA during fermentation of H. erinaceus. We succeeded with an optimum concentration of cofactor (CaCl 2 ), pH and temperature for improved protease activity and subsequent Gln and GA production. The ability of isolated E. faecalis strain to produce Gln and GA was demonstrated in this study. Further, upstream processes like strain improvement and media optimisation will direct the way to produce enriched H. erinaceus based FPB.

Comparative analysis of the Kao Dawk Mali 105 (KDML 105) premium rice variety, and its six mutants, obtained after low energy ion bombardment, was carried out for sensory and other consumer acceptance related important properties. Consumer acceptance test (n = 200), colour parameters (L*, a*, b*), grain length, and texture parameters of cooked rice and 2-Acetyl-1-pyrroline (2AP), amylose, fat, and protein contents of polished rice were determined. The consumer acceptance test showed that HyKOS3-1 and KDML 105 were equally accepted for every attribute, while HyKOS16 had lower colour liking than KDML 105. Other mutants of KDML 105 were less accepted than KDML 105. Preference mapping (PCA bi-plot) showed that the overall liking of cooked rice was positively correlated to 2AP and fat content and negatively correlated to hardness, cohesiveness, springiness, chewiness, amylose and protein contents. Consumers preferred cooked rice which has good aroma and soft texture. However, only 2AP content might be not enough to explain aroma liking of cooked rice and rice with different texture could be accepted in the same level of KDML 105.