We have isolated a new strain of Lactobacillus plantarum from Japanese pickles produced by a farmer in Hokkaido, and have named the strain HOKKAIDO. Our investigation of HOKKAIDO strain revealed several characteristics. The strain exhibits digestive juice tolerance and can survive in the intestine. The strain strongly adheres to human enterocyte-like Caco-2 cells, and cells of HOKKAIDO strain competed with E. coli O-157 cells for adhesion to Caco-2 cells. From several examinations with human dendritic cells, this strain may act to improve immune function. It was found that HOKKAIDO strain is superior in the fermentation of vegetables, fruits, and cereals. These characteristics were exploited to produce foods such as fermented soybean milk, alcoholic beverages using sake lees, and fermented carrot drink. In addition, HOKKAIDO strain as a probiotic was contained in commercial products such as yogurt and a milk substitute for calves.
Advanced technologies have been presented for optimum freezing and storage conditions based on the relationships between ice crystal morphology and food qualities such as color and sensory score. An improved method using cryo-adhesive film was proposed for quick measurement of ice crystal size and shape in frozen foods. The formation of ice crystals could make products less appealing and affect the sensory score of texture and palatability. Thus, relationships among freezing rate, ice crystal size, and color have been assessed quantitatively to investigate a temporary whitening effect on the surface of salmon fillets during freezing. Then, the size of ice crystals in frozen cooked rice was highly correlated with palatability score. Prediction methodologies for the optimum temperature conditions and inhibition temperature conditions of recrystallization to maintain the quality of frozen cooked rice have been proposed using artificial neural network models based on the size and fractal dimension of ice crystals. The quantitative analysis of ice crystals in foods provides useful information to demonstrate the effects on food quality and design practical models for optimum freezing and storage temperature conditions.
The conventional approach to preventing the onset of food allergy has been to prohibit pregnant/ lactating women and infants from consuming highly allergenic foods such as hen’s egg, cow’s milk and wheat. However, it has been shown that the avoidance of such foods by pregnant/ lactating mothers has no effect on preventing food allergy in infants. Furthermore, recent research suggests that early introduction of allergenic foods in the weaning diet prevents the onset of food allergy. We conducted a randomized, double-blind, placebo-controlled trial in which the subjects were infants with atopic dermatitis, and demonstrated that early introduction of hen’s egg at six months of age prevents the onset of egg allergy.
Recent years, many people have wanted to be healthier and paid attention to vitamin rich foods. However, vitamin contents in foods shown in tables of food composition do not always correspond to vitamins available for body, because dietary B-group vitamins exist as free-, cofactor- and bound-forms and human cannot completely digest and absorb the bound-form B-group vitamins. This manuscript shows our recent works to develop evaluation of vitamin nutritional status and bioavailability of B-group vitamins in diets and foods using urine samples as nutritional biomarkers. Especially, our results showed that eggs contained enough amounts of bioavailable pantothenic acid and biotin. Evaluation of bioavailability of B-group vitamins in foods and intake of foods such as eggs containing high bioavailable B-group vitamin is important to maintain health.