EFFECT OF PURPLE YAM (DIOSCOREA ALATA L.) MUCILAGE AS FAT REPLACER ON PHYSICAL, CHEMICAL, SENSORY PROPERTIES AND STORAGE ON LOW-FAT MUFFINS

Abstract

Consumers are increasingly seeking healthier and lower-calorie products without compromising on sensory appeal. This study hence investigated the replacement of oil in muffins with purple yam (Dioscorea alata L.) mucilage. Purple yam mucilage (PYM), chosen for its unique gel-forming properties and beneficial health characteristics, serves as an oil replacement. Purple yam mucilage exhibits a thick, gel-like substance that mimics certain functions of fats in recipes, such as providing moisture, texture, and mouthfeel. The study assessed the physicochemical properties, color, texture, sensory attributes, and changes after 7 days of storage by quantitative descriptive analysis. Substituting fat with PYM resulted in a reduction of fat content by up to 97.04% and a decrease in caloric content by up to 34.22%. Muffins with higher concentrations of PYM exhibited increased moisture content, ash, and carbohydrates while fat and caloric values decreased significantly (P£0.05). Texture properties of muffins with increased PYM concentration showed a notable decrease compared to the control sample. However, fat replacement with PYM up to 50% did not adversely affect baking loss or specific volume. Sensory evaluation indicated that muffins with 25% and 50% PYM substitution showed no significant difference compared to the control samples. In addition, after storage duration, quantitative descriptive analysis indicated that the control sample may end its shelf life due to the presence of obvious sticky crust and rancid aroma, while the muffins with 50% and upward fat replacement level retained the typical aroma but could get spoiled by microorganism. Therefore, the study suggests that replacing fat with M50 (50% PYM and 50% fat) in muffin could be suitable to develop reduced-fat muffins but further studies should be done on storage conditions for better shelf-life.