Folate contents, nutritional quality and consumer acceptability of yogurt fortified with red beetroot extract

Abstract

Folate is one of essential vitamin which plays an important role in human life. This vitamin cannot be synthesized by humans and must be obtained externally from foods to prevent folate deficiency. Folic acid, which is chemically synthesized form of folate, is often used for food fortification and supplementation, but higher intake can result into adverse effects such as vitamin B12 deficiency. Therefore, novel methods to increase concentrations of naturally occurring folate in foods have grabbed the interest of researchers. Bio-fortification of B vitamin folic acid in plain yogurt by using red beetroot as a novel strategy to increase “natural” folate levels was explored in this study. Yoghurt samples A (Control), B, C and D were produced at 0%, 5%, 10%, and 20% of milk substitutions with red beetroot powder. Proximate compositions, folate content and sensory analyses were determined to ascertain the quality attributes of the products. Folate content increased significantly (p<0.05) by 84.3, 84.4 and 88.8% with blended red beetroot extract samples at 5, 10 and 20%. The pH of samples containing 20% red beetroot extract significantly (p<0.05) decreased by a factor of 0.86; while titratable acidity was increased by a factor of 2.07 relative to the plain yoghurt. At 20% beetroot extract inclusion level, the protein content of the samples was significantly (p<0.05) increased by 21.25% relative to the control while fat content shows no significant difference. On the other hand, carbohydrate content of the plain yoghurt was significantly (p<0.05) reduced by 33.7 – 44.0% in the presence of red beetroot after the fermentation period. In sensory evaluation, there were no significant change of sensory attributes up to 10% additional with exception of texture. Overall, the study shows that fortification of yoghurt with red beetroot up to 10% enhances folate levels with minor physical and chemical changes.

Keywords: Folate, red beetroot, bio-fortification, yoghurt