Screening of Lactic Acid Bacteria Suitable for the Fermentation of Shenheling Slimming Beverages Based on the Activity Inhibition of Energy Digestive Enzymes and a Sensory Evaluation

Abstract

Obesity is a prevalent chronic disease worldwide. In this study, we screened lactic acid bacteria (LAB) suitable for fermenting Shenheling extract (SHLE) to enhance its anti-obesity efficacy and improve flavor. Using SHLE as the medium, a single strain was inoculated and the lactic acid bacteria suitable for growth in SHLE were preliminarily screened through a growth curve. The growth of the initially screened LAB was characterized in detail by the pH value, titration acidity and viable bacteria count. At the same time, appropriate LAB were selected with the lipase activity inhibition rate, α-glucosidase activity inhibition rate and a sensory evaluation as the response indicators. As a result, 6 of the 12 strains of lactic acid bacteria grew well in SHLE. The fermentation of five representative LAB could significantly improve the inhibition rate of the lipase activity of SHLE and maintain the inhibition rate of the α-glucosidase activity at a high level. In addition, fermentation removed the original flavors of SHLE such as grass, bitterness and cassia and added a sour taste, fruity aroma and cool taste. Among them, Lactobacillus fermentum grx08 and Lactobacillus rhamnosus hsryfm1301 gave SHLE a soft sour taste after fermentation. L. fermentum grx08, L. rhamnosus grx10 and hsryfm1301 imparted a moderately fruity aroma to SHLE after fermentation. In summary, L. fermentum grx08 and L. rhamnosus hsryfm1301 were the candidate strains for fermenting SHLE to produce good-flavored slimming functional drinks.