The physical properties of coffee caviar as influenced by sodium alginate concentration and calcium sources
W B Sunarharum, A D Kambodji, M Nur
Brawijaya Senso-Gastronomy Centre, Sensory and Applied Food Science, Faculty of Agricultural Technology, Universitas Brawijaya, Malang, Indonesia
Abstract
Coffee caviar is a product of spherification technique, which is one of well-known technique in molecular gastronomy field. Spherification is a process when liquid turns into spheres in a bath due to gelling mechanism. In application of basic spherification on coffee caviar, a solution consists of coffee and sodium alginate as a gelling agent are added to calcium bath using a syringe. The calcium bath can be made either with calcium chloride or calcium lactate, which is providing the missing ions for sodium alginate to start the gelling process. Proportion of sodium alginate, calcium chloride, and calcium lactate takes major role on the end result of coffee caviar, such as textures, viscosity, and gelling properties. This study aimed for finding the effect of sodium alginate (1%, 1.5% and 2 %) and calcium sources (calcium lactate or calcium chloride) to the physical characteristics of coffee caviar. The result showed that highest concentration of sodium alginate (2%) had the highest viscosity of 1120 cP, meanwhile the original coffee without sodium alginate had the viscosity of 200 cP. Higher concentration of sodium alginate also created a darker caviar. The effect of calcium source were on the texture and gellation speed to reach the gel strength. Calcium chloride with higher calcium content was more likely to give a faster gellation speed than calcium lactate, as well as the hardness of the gel, measured by TPA.
Keywords: coffee caviar, basic spherification, gelling properties, texture
Topic: AGRICULTURAL PRODUCT TECHNOLOGY