Karakteristik Umbi dan Pati Dua Varietas Ubi Jalar pada Berbagai Dosis Pupuk Kalium

Abstract

The research was conducted to find the effectof varieties and potassium fertilizer on the characterization of sweet potato and its starch. This research was performed in November 2010-September 2011 at the Laboratory of Food Technology, Agriculture Faculty, North Sumatera University, Medan and The Laboratory of Chemistry TechnicBogor Institute of Agriculture, using randomized block factorial design with two steps. The first, was planting two varieties of sweet potatoes (Sari and Beta-2) at four levels potassium fertilizer dosage (K0 = 0 kg/ha KCl, K1= 75 kg/ha KCl, K2 = 150 kg/ha KCl, and K3 = 225 kg/ha KCl). The second, was finding the thephysico-chemical and functionalanalysis were yield, whiteness, amilograph, paste clarity, and granular measurement, proximate analysis, amlyumand amylopektincontent, water and oil absorption capacity and starch solubility. The results showed that the sweet potato varieties of sweet potato gave highly significant effect on starch content, whiteness, paste clarity, peak viscosity, down viscosity, and starch solubility.Potassium fertilizer dosages gave highly significant effect on ash content, fibercontent, lipidcontent, proteincontent, starch content, amylopektincontent, and starch solubility. Interaction sweet potato Universitas Sumatera Utara varieties and potassium fertilizer dosages gave highly significant effect on the fiber content, starch content, and paste clarity.