Lactose absorption by postweaning rats from yogurt, quarg, and quarg whey

Area of Science:

• Food Science
• Gastroenterology
• Nutritional Science

Background:

• Lactose intolerance affects a significant portion of the global population.
• Fermented dairy products like yogurt are often better tolerated than milk.
• The mechanisms behind improved lactose digestion in fermented products require further elucidation.

Purpose of the Study:

• To investigate the effects of yogurt, quarg, and whey on lactose digestion in lactose-intolerant rats.
• To compare the efficacy of different fermented dairy products in alleviating lactose malabsorption symptoms.
• To explore the role of viable organisms, enzyme activity, and gastric emptying in lactose digestion.

Main Methods:

• Lactose-intolerant rats were fed diets containing yogurt, quarg (from yogurt and buttermilk cultures), and whey for 7 days.
• Lactose malabsorption was assessed by monitoring blood glucose levels and the occurrence of diarrhea.
• Gastrointestinal contents were analyzed for viable organisms and beta-galactosidase activity.

Main Results:

• Yogurt and quarg were well-tolerated, showing no significant blood glucose elevation or diarrhea.
• Whey induced severe diarrhea and poor lactose absorption, indicated by unchanged blood glucose levels.
• Quarg consumption confirmed the presence of viable organisms and beta-galactosidase activity in the gut.

Conclusions:

• Fermented dairy products, yogurt and quarg, facilitate lactose digestion in lactose-intolerant individuals.
• Whey products were associated with exacerbated lactose malabsorption symptoms.
• Viable organisms, exogenous lactase activity, and slower gastric emptying from quarg and yogurt contribute to improved lactose hydrolysis.