Physicochemical Characteristics of Three Local Sweet Potato Flour from East Kalimantan

Abstract

The character of local sweet potato flour is needed to give good results in food production. This research aims to investigate the physicochemical and functional properties of three verieties of sweet local potato flour from East Kalimantanr i.e Sawenter, White and Purple Kutim. The flour making process includes sorting, cleaning, peeling, soaking in metabisulfite 0.3%, draining, slicing, drying, milling and sieving. The results has a yield ranging from 26.93 to 28.86%; water content of 2.53 to 3.75% w/w; ash content of 1.95 to 5.11% w/w; protein content of 1.63 - 2.38% w/w; fat content of 0.6 to 1.15% w/w; fiber content from 2.72 to 3.3% w/w and carbohydrate by difference 85.13 to 88.6%, color (L = 73.15 to 95.63; a = -1.97 to +11.93, b = + 1,92- +16.52). The gelatinization temperature range 78.5 - 79,75°C; the maximum viscosity 596 - 1157 cP; breakdown viscosity 63-366 cP; setback viscosity 116-309 cP and final viscosity 436-972 cP. The granular form is polygonal and size between 2-12μm. This research is important because it can be applied as a mixed raw material in the manufacture of products that don’t require a high level of development such as brownies and biscuits.