Kestose is a type of oligosaccharide known to be well fermented by intestinal bacteria. We have demonstrated that kestose has various physiological functions, such as promotion of gut health, improvement of allergic diseases, and prevention of metabolic syndrome. These findings indicate that kestose is a prebiotic component that contributes to maintenance of health in humans through several physiological functions. We have also tried to improve the activity of an enzyme involved in kestose synthesis. Here we describe research on the physiological functions and practical uses of kestose.

Changes in postprandial blood glucose were measured after ingestion of two types of low-carbohydrate (CHO) bread in comparison with plain and whole-grain breads. The effects of a second meal and CHO digestibility were also investigated. The subjects were 11 healthy adults (2 males and 9 females). Plain (net CHO: 38.6 g), whole-grain (net CHO: 36 g), mildly low-CHO (net CHO: 8.5 g, high protein), and super-low-CHO (net CHO: 3.4 g, high protein and high fat) breads were ingested for breakfast. In addition, four tests were conducted in which curry and rice were eaten for lunch, and postprandial blood glucose was measured over time. CHO digestibility was measured using the in vitro Glucose Releasing Rate method. It was found that the blood glucose level was low after ingestion of mildly or super-low-CHO bread, but no second-meal effect was observed. In terms of digestibility, postprandial blood glucose level and satiety, mildly low-CHO bread was considered to be superior among the two types of low-CHO bread used in this study.