Development and Nutritional Evaluation of Sweet Potato Flour from Osmotically Dehydrated Roots

Despite the well-established advantages of osmotic dehydration for conserving quality, its use in flour production has been poorly explored. Therefore, this study addresses how osmotic dehydration can enhance nutrient retention in sweet potato flour compared to traditional drying methods. Thus, this study designs an efficient method of processing sweet potato flour using osmotically dried roots to evaluate its proximate nutritional profile compared to conventionally dried roots. Local sweet potato varieties were treated with osmotic solutions by using sucrose solutions in varying levels (40% or 50%) and 60% in addition to temperatures (30-600C) and then followed by milling, drying and packing. Results showed sweet potato flour from osmotically dried roots, derived from 60 samples (30 per variety, Local Sada and Kamala Sundari), had significantly higher levels of sugars, protein, and ash (p < 0.05, as determined by Duncan’s Multiple Range Test [DMRT]) despite maintaining satisfactory levels of moisture and lipids when compared with the conventionally dried version. The results indicate that the process of osmotherapy efficiently improves the retention of nutrients and can enhance the flour’s functionality for food processing. The results suggest that osmotic dehydration does more than preserve but can also improve certain aspects of nutrition in sweet potatoes, primarily due to lower exposure to temperatures at high temperatures, which can destroy vitamins such as beta-carotene. The study’s sensory analysis revealed that although there were some variations in texture and taste, the acceptance of consumers was very high. Osmotic dehydration can be a feasible method of producing sweet potato flour with a better nutritional profile, which is ideal for baking applications.