Sifat Fisik dan Kimia Chips Gadung Rendah HCN Hasil Peyerapan Jenis Abu dan Lama Perendaman dalam Air Mengalir

Abstract

Gadung tubers are a potential local carbohydrate source but contain naturally occurring hydrogen cyanide (HCN), which must be reduced before consumption. Traditional detoxification commonly combines ash application with prolonged soaking; however, a more efficient treatment is needed to produce safe gadung chips while maintaining their physical and chemical quality. This study aimed to evaluate the effects of wood ash and rice husk ash and different soaking durations in flowing water on HCN reduction and the physical and chemical characteristics of gadung chips. A two-factor randomized block design was used, comprising ash type (wood ash and rice husk ash) and soaking duration (24, 48, and 72 h), with three replications. Each experimental unit used 6 kg of fresh gadung chips. The evaluated responses were yield, lightness, expansion capacity, moisture content, ash content, and HCN content. Data were analyzed using analysis of variance at a 95% confidence level, followed by Duncan’s Multiple Range Test. Ash type, soaking duration, and their interaction significantly affected the evaluated characteristics. Rice husk ash increased yield, ash content, and residual HCN content but reduced lightness, expansion capacity, and moisture content compared with wood ash. Longer soaking increased lightness, expansion capacity, and ash content while reducing yield, moisture content, and HCN content. Yield ranged from 18.08% to 21.99%, lightness from 40.45 to 60.88, expansion capacity from 39.07% to 53.65%, moisture content from 11.75% to 14.49%, ash content from 2.21% to 2.53%, and HCN content from 7.43 to 20.55 ppm.