In vitro bioaccessibilities of vitamin C in baby biscuits prepared with or without UHT cow’s milk

Abstract

Vitamins C is an essential nutritional component of complementary baby foods. Knowing the bioaccessibility of vitamin C is important to determine daily vitamin intake for infants and young children. There is not enough information about the bioaccessibility of vitamin C added to baby biscuits and follow-on milk and the effect of UHT milk on vitamin C bioaccessibility. This study aimed to examine the bioaccessibility of vitamin C in baby biscuits and follow-on milk by an in vitro gastrointestinal system at different pH levels. Measured vitamin C concentrations were generally lower than the amounts declared on their labels. The average bioaccessibility of vitamin C in baby biscuits with and without added UHT cow's milk was 18.27 % and 0.34 % at gastric pH 1.5, respectively. It was 13.7 % and 0.30 % for gastric pH 4, respectively. The average bioaccessibility of vitamin C in follow-on milk was only 9.8 % and 9.1 %. In comparison, the bioaccessibility of naturally occurring vitamin C in UHT cow's milk was 91.6 % and 90.5 % at gastric pH 1.5 and gastric pH 4, respectively. As revealed in this research, the bioaccessibility of vitamin C in baby biscuits with UHT cow's milk was higher than that without adding UHT cow's milk in both gastric pH conditions. Naturally occurring vitamin C in milk was more bioaccessible in both gastric pH 1.5 and pH 4. • Vitamin C bioaccessibility in baby biscuits prepared with UHT cow's milk was high • Bioaccessibility of vitamin C at gastric pH 4 was lower than gastric pH 1.5. • Naturally occurring vitamin C in milk was more bioaccessible at two gastric pHs. • Vitamin C bioaccessibility may be related to binding with some specific proteins.