71A-32 |
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S. Rattanasuwan and W. TUNGJAROENCHAI. Faculty of Agricultural Industry, King Mongkut's Institute of Technology, Ladkrabang, Bangkok, Thailand Addition of milk solids is a routine method to improve the texture of milk products. Inclusion of wheat starch has been used to improve the texture of yogurt, which resulted in an increased consistency of product with cleaner flavor and cereal notes. Research work on using tropical starch such as tapioca, waxy maize, and waxy rice starch in yogurt is limited. Our objective was to investigate the effects of modified tapioca, waxy maize, and waxy rice starch on texture, syneresis, whey holding capacity (WHC), microstructure, and sensory quality of low-fat set yogurt. Low-fat set yogurt was made by using a commercial DVS freeze-dried culture (YC 830). Modified tapioca (MTS), waxy maize (WMS), or waxy rice starch (WRS) was included in levels of 0, 0.5, 1.0, and 2.0% (w/w). Incubation was done at a temperature range of 42 to 45 °C for 6 hr. A TA.XT2 texture analyzer was used to evaluate texture of yogurt. Syneresis and WHC of yogurt were determined by the drain and centrifugation methods. Microstructure was viewed under scanning electron microscope (SEM). Twenty panelists performed preference test with 7 Hedonic scales. MTS increased the firmness of yogurt greater than those of WMR or WRS. WRS had the least effect on the firmness quality. Starch increased WHC and decreased syneresis of the curd. Scanning electron micrographs (SEM) suggested that starch granules helped stabilization of casein network. Yogurt containing 1.0% MTS and 2.0% WRS received the highest flavor scores. WMS and MTS imparted a poor taste quality in yogurt. WRS at 2.0% was recommended for low-fat set yogurt with a cleaner flavor. Starch could be used to improve or modify texture of yogurt. Starch stabilizers could help correct the problem of cooked flavor by excessive use of skim milk powder.
Session 71A, Dairy Foods: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |