Effect of Xanthan Gum and Guar Gum on the Qualities of Boba from Germinated Brown Rice Flour and Germinated Black Glutinous Rice Flour Substituted Cassava Flour

Abstract

The aim of this research was to develop boba products by using germinated brown rice flour and germinated black glutinous rice flour. The basic formula of boba is made with cassava flour. Mixture design was used to optimize the formula of the boba production from three variables: cassava flour (45-85%), germinated brown rice flour (5-35%), and germinated black glutinous rice flour (10-50%) on the physical and sensory qualities of the product. The results showed that decreasing cassava flour content decreased the lightness, hardness and gumminess of boba. Increasing of germinated brown rice flour decreased the hardness and gumminess of boba. An increasing in amount of germinated black glutinous rice flour in boba resulted in higher values of hardness and stickiness than boba with germinated rice flour. Boba made with 85% cassava flour, 5 % germinated brown rice flour and 10% black germinated glutinous rice flour had liking score closest to the basic formula. The effects of the xanthan gum to guar gum ratio at 0:1, 1:0, 0.75:0.25, 0.25:0.75 and 0.5:0.5 on the physical and sensory qualities of the product were investigated. The formula without xanthan gum and guar gum served as control. Results showed that, compared to the control, the addition of xanthan gum and guar gum increased lightness, yellowness, hardness and gumminess. The most desirable level of xanthan-guar gum was at 0.25:0.74%, as it improved textural quality and had the highest liking score of the boba. The developed boba had moisture, carbohydrates, fats, proteins, ash and crude fibers which were 71.58, 99.51, 0.20, 0.11, 0.18 and 0.0029, respectively. The energy value determined by Bomb calorimeter which was 173.08 kcal per 1 serving (43 g).