Culture-Dependent and -Independent Methods to Investigate the Predominant Microorganisms Associated with Wet Processed Coffee.
The fermentation process of Yunnan arabica coffee is a typical wet fermentation. Its excellent quality is closely related to microbes in the process of fermentation. The purpose of this study was to isolate and identify the microorganisms in the wet method of coffee processing in Yunnan Province, China. Microbial community structure and dominant bacterial species were evaluated by traditional cultivated separation method and PCR-DGGE technology, and were further analyzed in combination with the changes of organic acid content, activity of pectinase, and physical parameters (pH and temperature). A large number of microorganisms which can produce pectinase were found. Among them, Enterobacter cowanii, Pantoea agglomerans, Enterobacteriaceae bacterium, and Rahnella aquatilis were the predominant gram-negative bacteria, Bacillus cereus was the predominant gram-positive bacterium, Pichia kluyveri, Hanseniaspora uvarum, and Pichia fermentans were the predominant yeasts, and all those are pectinase-producing microorganisms. As for the contents of organic acids, oxalic was the highest, followed by acetic and lactic acids. Butyrate and propionate, which were unfavorable during the fermentation period, were barely discovered.
College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.
Xiaomin
X
Feng
College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.
Honghong
H
Dong
College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.
Pan
P
Yang
Pu'er Institute of Pu-erh Tea, Pu'er City, 665000, Yunnan, China.
Ruijuan
R
Yang
Institute for Applied Ecology New Zealand, School of Applied Sciences, Faculty of Health and Environmental Sciences, Auckland University of Technology, Auckland, New Zealand.|School of Interprofessional Health Studies, Faculty of Health and Environmental Sciences, Auckland University of Technology, Auckland, New Zealand.|Institute of Biomedical Technology, Auckland University of Technology, Auckland, New Zealand.
Jun
J
Lu
College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China. lvjie@mail.buct.edu.cn.
Jie
J
Lv
Faculty of Food Science and Technology, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. shengj@ynau.edu.cn.
Jun
J
Sheng
D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D002681:China; D040503:Coffea / Q000378:metabolism / Q000382:microbiology*; D003069:Coffee; D005285:Fermentation; D005511:Food Handling; D016133:Polymerase Chain Reaction; D015003:Yeasts / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
D003069:Coffee