Effect of Pre-treatments on the Osmotic Dehydration and Mass Transfer Behaviour of Sweet Potatoes (Ipomoea batatas Lam.)

Food security is increasingly threatened by rapid population growth, climate change, and resource constraints, necessitating efficient preservation techniques to minimize post-harvest losses. This study investigates the osmotic dehydration process of two sweet potato (Ipomoea batatas Lam.) varieties, Local Sada and Kamala Sundari, under varying sugar concentrations (40%, 50%, 60%), temperatures (30°C, 40°C, 50°C, and 60°C), slice thickness (3 mm or 5 mm), and pre-treatment conditions (blanched or unblanched). The research problem addresses the high perishability of sweet potatoes post-harvest, leading to significant food losses, and the lack of optimized osmotic dehydration parameters tailored to specific sweet potato varieties. The novelty of this study lies in its comprehensive examination of multiple processing parameters simultaneously within a single experimental framework, allowing for an in-depth understanding of mass transfer mechanisms and varietal differences. Results indicate that increased sugar concentrations and temperatures enhance dehydration rates, with blanching further accelerating mass transfer by increasing cell permeability. However, varietal differences were significant: Kamala Sundari exhibited slower yet more controlled dehydration, maintaining better structural integrity, while Local Sada dehydrated faster but showed higher susceptibility to structural collapse. Slice thickness also played a crucial role, as thinner slices (3 mm) dehydrated more quickly but were prone to texture loss compared to thicker slices (5 mm). Unblanched samples, despite slower dehydration rates, retained better textural attributes. These findings have strong industrial relevance, providing a framework for optimizing osmotic dehydration conditions tailored to different sweet potato varieties, ensuring improved product quality and reduced post-harvest losses in food processing industries.