Fruit Covered Functional Candied Chestnut Production: Nutritional and Technological Effects of Riboflavin Fortification and Copigmentation ^†

Abstract

The food industry offers innovative approaches in accordance with the changing demands of consumers. Developing functional formulations that may have positive effects on human health in addition to the nutritional feature of food has become a very popular approach. Chestnut (Castanea sativa Mill.) has many ways of being consumed, and one of them is candied chestnuts. Candied chestnuts, which are one of the gastronomic products, is offered on the market as whole or broken. Broken candied chestnuts, which have less economic value than whole candied chestnuts, are consumed directly or with a chocolate coating. There are no examples of fruit-coated candied chestnut production. The objective of this research was to produce an alternative and functional new food product by coating broken chestnut candies with pomegranate juice concentrate. Within the scope of the research, four different formulations of fruit-coated candied chestnuts were produced: candied chestnuts coated with solely pomegranate juice concentrate (I), pomegranate juice concentrate coated candied chestnuts with copigment agent (II), riboflavin fortified pomegranate juice concentrate coated candied chestnuts (III), and candied chestnuts coated with riboflavin-fortified and copigment agent added pomegranate juice concentrate (IV). Pomegranate peel phenolic extract as a copigment agent was obtained via microwave-assisted extraction followed by evaporation. The added amount of copigment agent was decided by determining the total phenolic content of the obtained extract (23.1 mg GAE/g) and the total monomeric anthocyanin content of the pomegranate juice (62.7 mg cyn-3-glu/kg). Riboflavin was added to the coating material at a ratio of 50 mg/product to meet the daily intake of individuals. The products were finally packed via aluminum polyethylene (ALPE) packages and stored for two months at 4 °C. Texture, color, total phenolic content, anthocyanin content and antioxidant capacity analyses were performed each 15 days of the 60-day storage period. This study was financially supported with a fund from The Scientific and Technological Research Council of Türkiye (TUBITAK-BIDEB 2209-A).