Use of humectants in mulberry paste product

Abstract

The shelf-life extension of mulberry paste by using humectants to place sugar content could maintain the moisture while reducing the water activity (aw) of the product. The objectives of this research were to study on humectants replacement and the changes of the mulberry paste product quality during storage. The sugar content in the standard formula was replaced by 10% w/w glycerol and 90% w/w of maltitol and maltodextrin mixture (20:80 w/w). The final mulberry paste product consisted of mulberry, maltodextrin, maltitol, glycerol, salt and citric acid by 69.80% 21.62% 5.40% 3.01%, 0.17% and 0.07%, respectively. The chemical compositions: carbohydrates, proteins, fat, ash, fiber, and moisture, of the product were 76.92% 2.39% 0.14% 4.19% 4.30% 12.06%, respectively. The total energy by calculation was 318.50 kcal/100 g. The anthocyanin content was 68.32 mg cyanidin- 3-glucoside/g. Total titratable acidity (citric acid equivalent) was 0.60%. The reducing sugar and total sugar values were 1.74% and 3.90%, respectively. The consumer acceptance as evaluated by untrained panelists was in the level of moderately like (7 score). The product packed in glass bottle containers was stored at 27±2 ºC for 4 weeks. The aw was increased while the textural properties: hardness, adhesiveness, and chewiness, were decreased. The chemical quality analysis showed significant decreases (p≤0.05) in the moisture and the anthocyanin contents. The microbial quality; total plate count and yeast and mold measurements were significantly increased (p≤0.05), however, the values were within the acceptable range according to the Thai community product standard (35/2558).