EFFECTS OF PUREE PROCESSING METHODS ON THE TEXTURAL CHARACTERISTICS OF AN ALGINATE- TEXTURIZED SWEET POTATO PRODUCT

The objective was to determine the effect of sweet potato (SP) puree preparation methods on the properties of texturized SP products. The treatments were separated into two main types in which sliced SPs were cooked prior to puree preparation, or purees were prepared by grinding raw roots, followed by heat processing using steam injection. Purees from each treatment were texturized into cylinders 12.7 cm long and 5.5 cm in diameter, using an alginate-calcium system, and frozen. We found that cooked purees prepared by steam injection of raw purees had higher viscosities than did purees made from cooked SP. Texture Profile Analysis (TPA) revealed that texturized product made from SP cooked before puree preparation was the most fracturable and least springy of the texturized products. Sensory panelists did not express apreference for texturized product from any of the treatments, but 23% of the panelists noted a grainy texture and/or raw root aroma in products prepared by steam injection of raw purees. In view of these observations and the fact that puree preparation from cooked SP is the simplest process, this process appears to be the best for this type of texturized SP product.