Effects of Blanching Parameters and Partial Drying on the Physicochemical Properties of Sweet Potato Slices

This study assesses the effects of temperature and time in hot water blanching on physical and biochemical properties of sweet potato slices. It also aimed to identify suitable blanching conditions followed by partial drying at 90°C to reduce moisture content for producing semi-perishable sweet potato slices. Sweet potato slices were blanched at various temperatures from 80°C to 100°C for 60 to 300 seconds durations. The results showed that the most favourable blanching settings was 100°C for 300 seconds, which resulted in the maximum total sugar and ascorbic acid content retention, as well as the best sensory properties. The chemical parameters on selected blanching settings of 100°C for 300 seconds were as 16.56±0.5 mg 100g^-1 ascorbic acid, 17.59±0.78% total sugar, and 5.6±0.0 pH. It was observed that it took 300 min to reach the moisture content of 30% on wet basis with an average drying rate of 6.3 g water g^-1 of dry matter min^-1. This study provides a scientific basis for selecting appropriate blanching and partial drying conditions to produce semi-perishable sweet potato slices with improved nutritional retention, sensory quality, and shelf-life.