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This study was conducted to investigate the isolation,
identification and characteristics of lactic acid bacteria and
yeasts in kefir starters. The kefir starters were obtained
from Xien-zhu and Taipei region in Taiwan. counts of lactic
acid bacteria in kefir form Xien-zhu and Taipei were 8.6±0.1log
CFU/ml and 8.9±0.1 log CFU/ml, respectively. Counts of yeast in
these two kinds of kefir were 6.9±0.1 log CFU/ml and 5.2±0.1
log CFU/ml, respectively. Kefir from Taipei had the better
performance of titratable acidity, viscosity and water-holding
capacity, but its ethanol content was lower than that from
Xien-zhu. The lactic acid bacteria isolated from the kefir
starter from Xien-zhuwere identified as Lactobacillus helveticus
and Leuconostoc mesenteroides, andthe isolates of yeasts were
identified as Kluyveromyces marxianus. The lacticacid bacteria
isolated from the kefir starter from Taipei were identified
asLeu. mesenteroides, and the yeasts were identified as Kluy.
marxianus and Pichia fermentans. From the results of the
studies on the growth charac-teristics of the above strains,
L. helveticus was possessed of better growthcharacteristics, and
Kluy. marxianus exhibited better L(+)-lactic acid produc-tion.
D(-)-lactic acid was the major form produced from Leu.
mesenteroides, and the isolates of kefir from Taipei exhibited
better production than thosefrom Xien-zhu. P. fermentans was a
lactose-nonfermenting yeast, therefore theactive proteolytic
enzymes was essential for its growth in milk.
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