Effect of Blending Ratio, Cooking method and Cooking Time on Physicochemical, Nutritional Content and Sensory Acceptability of Tamarind (Tamarindus Indica) and Orange- Fleshed Sweet Potato (Ipomoea Batatas L.) Jam

Abstract

Underutilized crops like tamarind (Tamarindus indica) and orange-fleshed sweet potatoes (OFSP, Ipomoea batatas L.) have the potential to diversify Ethiopian diets, enhance nutrition, and lower postharvest losses. Despite their nutritional advantages, vitamin A and C deficits are still common, which emphasizes the demand for goods made from these crops that have added value. The objective of this study was to create and assess the physicochemical, nutritional, and sensory characteristics of jam made from blends of tamarind and OFSP. Three cooking methods (microwave, dry heat, and pressure cooking), three cooking times (20, 30, and 40 minutes), and three blending ratios (90:10, 80:20, and 70:30 OFSP:tamarind) were used in the study's fully randomized factorial experiment. Proximate composition, vitamin and mineral levels, and sensory appeal were among the parameters examined. The findings showed that the blending ratios had a substantial (p < 0.05) impact on the composition of nutrients. Blends rich in tamarinds had higher levels of protein (3.42%), ash (2.81%), iron (3.1 mg/100 g), zinc (1.42 mg/100 g), and vitamin C (19.36 mg/100 g), whereas blends rich in OFSP had higher levels of utilizable carbohydrates (75.6%), crude fiber (2.15%), calcium (54.8 mg/100 g), magnesium (23.6 mg/100 g), and β-carotene (5.21 mg/100 g). Cooking times affected vitamin stability; longer cooking times decreased the preservation of β-carotene while decreasing vitamin C. The combination of 70% OFSP and 30% tamarind cooked for 20 minutes was found to be the most acceptable by sensory evaluation; on a 7-point hedonic scale, it scored highest for taste (6.1), color (5.9), texture (5.8), scent (5.6), and overall acceptability (6.2). Overall, the OFSP– tamarind blended jam is a nutritionally improved, and technically viable product. Its production has the potential to improve food diversity, lessen postharvest losses, and address vitamin A and C shortages