Development and quality evaluation of ready to eat product from elephant foot yam tuber (Amorphophallus spp.)

Abstract

Osmotic dehydration process for development of ready to eat elephant foot yam product was optimized using response surface methodology and quality of raw and optimized samples was compared. Optimal conditions were 64°Brix osmotic solution concentration, 59 °C temperature and 180 min processing time. The moisture content of osmo-dried samples was reduced to 18 ± 0.75 g/100 g (wet basis) by hot air drying. Under optimum conditions, the values of water loss, solute gain, water activity, L-value, and overall acceptability of optimized sample were 51.7 g/100 g, 16.32 g/100 g, 0.69, 15.12 and 8.82, respectively. Comparative study revealed that protein content was significantly altered and no significant changes were observed in fat, ash, and, phenolic contents of optimized or raw samples. Also, when compared to raw samples, the increase in crude fiber content, decrease in hardness (N), water activity, and oxalate content was observed in optimized sample. Furthermore, optimized osmo-dried samples showed fewer micro-structural changes as compared to samples dried without osmotic dehydration. We conclude that optimized product is highly palatable and nutritionally comparable to raw elephant foot yam samples thus making it possible to use this medicinal and nutritional crop in regular diet.