Abstract:
In this study, to reveal the physicochemical properties and microbial taxa of Hong Qu produced in Shandong, China three Hong Qu samples were collected from a Shandong Qu-making company, and based on the determination of their physicochemical indexes and fermentation characteristics, the microbial taxa were resolved using MiSeq high-throughput sequencing technology, and the
Bacillus and lactic acid bacteria contained in them were isolated and identified. The results showed that the moisture content of the three Hong Qu samples ranged from 8.27% to 10.30%, acidity ranged from 1.0 to 1.3 mmol/10 g, amino acid nitrogen content ranged from 131.65 to 172.76 mg/100 g, saccharification power ranged from 476 to 764 U/g, esterification power ranged from 331 to 548 U/g, and fermentation power, liquefaction power and alcoholization power were less than 10 U/g. The bacterial taxa of Hong Qu were mainly composed of
Weissella (41.93%) and
Acetobacter (9.99%), and the fungal taxa were mainly composed of
Pichia (55.83%) and
Monascus (21.24%), where the correlation between bacteria and alcoholization power was significant, and while the correlation between fungi and saccharification power was significant (
P<0.05).
Bacillus siamensis (
B. siamensis) accounted for 79.17% of the
Bacillus isolates and
Pediococcus pentosaceus (
P. pentosaceus) accounted for 55.55% of the lactic acid bacteria isolates. This shows that the
Bacillus and lactic acid bacteria taxa included in this study mainly consisted of
B. siamensis and
P. pentosaceus, and the low content of
Monascus and high content of
Pichia might be the main reason for their low saccharification power.