Effect of compositions on physicochemical properties and rheological behavior of gelatinized adzuki-bean cake (Yokan)

Abstract

Gelatinized adzuki-bean cake (commonly known as Yokan or Yanggaeng) is one of Asia's favorite bean snacks. This product as a continuous phase structure, which is embedded with the dispersed phase formed by adzuki bean paste, which is prepared by the combination of agar and sugar. The gel characteristics of gelatinized adzuki-bean cake are influenced by the physical properties of agar, sugar, and the adzuki bean paste and are highly correlated to its product quality. An analysis was carried out using a Rapid Visco Analyzer on the adzuki bean powder to investigate the feasibility of simplifying its preparation process and reducing the amount of agar used in it. The effect of starch contained in the adzuki bean powder on the gelling capacity was also investigated. The gelatinous properties and viscoelasticity of gelatinized adzuki-bean cake were affected by the textural properties of adzuki bean paste, agar, and sugar. The results showed that the structured bean paste particles were distributed in the continuous phase formed by agar and sugar. These particles formed a gelatinous product with a homogeneous dispersion system following a long cooking period and concentration.