Improvement of the Texture of Yogurt by Use of Exopolysaccharide Producing Lactic Acid Bacteria.
19 Streptococcus thermophilus with high exopolysaccharide production were isolated from traditional Chinese fermented dairy products. The exopolysaccharide and viscosity of milk fermented by these 19 isolates were assayed. The strains of Streptococcus thermophilus zlw TM11 were selected because its fermented milk had the highest exopolysaccharide content (380 mg/L) and viscosity (7716 mpa/s). Then Streptococcus thermophilus zlw TM11 was combined with Lactobacillus delbrueckii subsp. bulgaricus 3 4.5 and the combination was named SH-1. The quality of the yogurt fermented by SH-1 and two commercial starter cultures (YO-MIX 465, YF-L711) were compared. It was shown that the exopolysaccharide content of yogurt fermented by SH-1 was similar to that of yogurt fermented by YF-L711 and significantly higher than YO-MIX 465 (p < 0.05). In addition, the yogurt fermented by SH-1 had the lowest syneresis (8.5%) and better texture and sensory than the samples fermented by YO-MIX 465 and YF-L711. It manifested that the selected higher exopolysaccharide production starter SH-1 could be used as yogurt starter and reduce the amount of adding stabilizer, which can compare with the imported commercial starter culture.
School of Chemical Engineering & Technology, Harbin Institute of Technology, Harbin 150090, China.
Xue
X
Han
School of Chemical Engineering & Technology, Harbin Institute of Technology, Harbin 150090, China.
Zhe
Z
Yang
School of Chemical Engineering & Technology, Harbin Institute of Technology, Harbin 150090, China.
Xueping
X
Jing
Dairy Research Institute, Bright Dairy & Food Co., Ltd., Building 2, No. 1518, West Jiangchang Road, Shanghai 200436, China.
Peng
P
Yu
School of Chemical Engineering & Technology, Harbin Institute of Technology, Harbin 150090, China.
Yingchun
Y
Zhang
School of Chemical Engineering & Technology, Harbin Institute of Technology, Harbin 150090, China.
Huaxi
0000-0002-6071-7113
H
Yi
School of Chemical Engineering & Technology, Harbin Institute of Technology, Harbin 150090, China.
Lanwei
0000-0003-3459-2975
L
Zhang
D000818:Animals; D005504:Food Analysis; D005516:Food Microbiology / Q000379:methods*; D019344:Lactic Acid / Q000096:biosynthesis / Q000378:metabolism; D008892:Milk / Q000737:chemistry / Q000382:microbiology*; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis* / Q000737:chemistry; D048249:Streptococcus thermophilus / Q000378:metabolism*; D014783:Viscosity; D015014:Yogurt / Q000032:analysis* / Q000382:microbiology*
D011135:Polysaccharides, Bacterial; D019344:Lactic Acid