Search

Six different ganjang batches were prepared and the microbial communities in the ganjang samples and raw materials (meju and solar salts), as well as the metabolites generated during fermentation were analyzed. The varying amounts of raw materials used differentially affected the microbial communities. Halophilic or halotolerant microbes derived from solar salts were abundant during middle or late fermentation. By contrast, non-halophilic microbes derived from meju were abundant mainly during early fermentation. Debaryomyces, Tetragenococcus, and Staphylococcus were abundant in all ganjang batches, which suggested that these may be the most common microbes involved in ganjang fermentation. The salt concentrations did not affect the abundance of Debaryomyces, which was abundant in all ganjang batches. Tetragenococcus was abundant in low salt ganjang, whereas Staphylococcus was abundant in high salt ganjang. Metabolite analysis revealed that carbohydrate concentrations were high in ganjang prepared using high amounts of meju. The level of lactate, which may be largely produced by Tetragenococcus, in low salt ganjang was high because of high microbial activity. The amino acid concentrations of the ganjang batches were mainly associated with meju quantity, but not salt concentration. These results indicated that the production of amino acids may be associated with indigenous proteases in meju, but not microbial activities during ganjang fermentation., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Three types of meongge ( Halocynthia roretzi ) jeotgal (MJ) were prepared with 3 different types of salts (12%, w/v): purified salt (PS), solar salt aged for 3 years (SS), and bamboo salt that had been recrystalized 3 times (BS). One set of MJ was fermented with starters, Bacillus subtilis JS2 and Tetragenococcus halophilus BS1-37 (each 6 log CFU/g), and another set without starters for 42 days at 10°C. The LAB count of the SSMJ (non-starter) was highest at day 28 (2.30 log CFU/g). The pH of the PSMJ and SSMJ was 5.72-5.77 at day 0, and 5.40-5.50 at day 42. BSMJ showed higher pH and lower titratable acidities than other samples. Amino-type nitrogen (ANN) increased continuously, and SSMJ showed higher values than other samples from day 14. Bacterial species of non-starter MJ were examined by culture independent method. Clone libraries of 16S rRNA genes were constructed in Escherichia coli from total DNA from nonstarter MJ samples at day 0, 14, and 28. Thirty clones per each sample were randomly selected and DNA sequences were analyzed. Variovorax sp., uncultured bacterium, and Acidovorax sp. were the most dominant group at day 0, 14, and 28, respectively. Lactobacillus sakei and Streptococcus sp. were the next dominant group in SSMJ at day 28. A Streptococcus sp. was detected from PSMJ at day 28. Sensory evaluation for MJ samples at day 28 showed that SSMJ got higher overall acceptability scores. These results showed that solar salt can cause desirable changes in the microbial community of fermented foods, thereby positively affecting their overall quality.

Halapricum salinum CBA1105(T) (=KCTC 4202(T), JCM 19729(T)) is an extremely halophilic archaeon isolated from solar salt in the Republic of Korea. We present the draft genome of CBA1105(T), which is assembled into 3 contigs containing 3,451,492bp with a G+C content of 63.7%. This is the first genome that has been sequenced in the genus Halapricum., (Copyright © 2014 Elsevier B.V. All rights reserved.)