Production technology, nutritional, and microbiological investigation of traditionally fermented mare milk (Chigee) from Xilin Gol in China

Abstract

Mare milk originated from female horses, known as mares, to feed their foals during lactation. The health‐promoting characteristics of traditionally fermented mare milk (Chigee) are well known for the function of clinic treatment in the traditional Mongolian medicine. This study was conducted to investigate the production technology of Chigee and to evaluate the nutritional and microbiological characteristics of mare milk and Chigee based on 188 samples. The nutritional analysis of mare milk and Chigee indicated that lactose significantly decreased from 6.95 ± 0.45% to 2.82 ± 1.65% and acidity and alcoholic content significantly increased to 136.72 ± 57.88°T and 1.22 ± 0.7%, respectively, after spontaneous fermentation of mare milk. The microbiological analysis of Chigee showed that the total lactic acid bacteria (LAB) count varied from 5.32 to 8.56 log cfu/ml and total yeast count varied from 2.41 to 6.98 log cfu/ml. Moreover, the acidity of Chigee rose with the increase in LAB count within limits, and high acidity (≥178°T) inhibited the growth of coliforms. These findings provide an understanding of traditional production technology, nutrition, and microbiology that is fundamental for establishing the food standard of Chigee in China and will contribute to standardize the fermentation process for the industrial production of Chigee in the future.

Comparison of Bacterial Microbiota in Raw Mare’s Milk and Koumiss Using PacBio Single Molecule Real-Time Sequencing Technology

“…Most samples had rich and complex bacterial community (shown in a heatmap, Figure 3B). In addition, a small proportion of sequences of raw mare's milk represented potential pathogens/contaminants such as S. aureus, A. lwoffii, Klebsiella (K.) oxytoca, K. pneumoniae, E. faecalis, Enterobacter cloacae, which were possibly acquired via infection of the mare's teats or from environmental contamination (Quigley et al, 2013;Guo et al, 2020).…”

“…The decrease in the level of S. succinus could be a result of the increasing acidity along the koumiss fermentation process. The increase in acidity as koumiss fermentation progressed possibly selected for acid-tolerant species like L. helveticus (Quigley et al, 2013;Guo et al, 2020).…”

“…The types and functions of microbiome found in the two kinds of dairy products were possibly selected by the nutritional components and acidity in the two distinct dairy environments. The high contents of milk lactose, protein, fat, vitamins, minerals and essential amino acids, as well as the high water activity and slightly neutral pH, might provide an ideal environment that not only supported the microbial growth (Gesudu et al, 2016;Guo et al, 2020) but the development of a wide microbial diversity (Bilige et al, 2009). Meanwhile, it could also increase the potential for harboring potential pathogens like S. succinus, which might increase the risk of infection.…”

“…The overall acidic environment in koumiss might also help extend its shelf life, since many lactobacilli are regarded as probiotics and can produce bioactive materials. These microbial originated bioactive materials might be related with the health-promoting effect of koumiss (Hou et al, 2019;Guo et al, 2020).…”

“…Moreover, no study has yet compared the microbiota structure and composition between raw mare's milk, the raw material of koumiss, and its fermented product. In addition, culture-independent methods are more sensitive and accurate in providing ample biological information (Menghe et al, 2004;Gesudu et al, 2016;Mulyawati et al, 2019;Guo et al, 2020).…”