36G-7 |
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A. R. TAHERIAN, A. Bégin, and E.-A. Levesque. Food Research and Development Centre, Agriculture and Agri-Food Canada, Processed Plant Products, 3600 Casavant Blvd. W., Saint-Hyacinthe, QC J2S 8E3, Canada Commercial hydrocolloids and their mixtures are used in frozen desserts to impart texture and palatability to the final product and to protect the whipped product against excessive drainage during storage. The mechanism of stabilization by hydrocolloids in foamed emulsions is not yet fully known, and a clear understanding of their role is needed to improve functionality and extend shelf life. Contributions of maltodextrin and arabic gum to flow and dynamic properties, glass transition, particle size and distribution, water-holding capacity, and texture of nondairy emulsions, in forms of mix and frozen foam, were investigated. The results were then compared to the properties driven from a commercial ice cream mix at both mix and frozen states. An identical procedure was used to prepare foamed emulsions, and all samples were stored for one week at -20°C prior to examinations. Rheological and textural characteristics of mix and frozen were determined using an AR-1000N Rheometer equipped with a 60mm cone of 2° C and a TA-XT2 Texture Analyzer attached with a 50mm circular probe. Glass transition temperatures were also measured using a Universal V2.5H TA Instruments differential scanning colorimetry. Examination of flow and dynamic properties of prepared mixes indicated a higher viscosity and flow behavior index for the mix prepared with maltodextrin. All mixes indicated pseudoplastic behavior and G' or elastic modulus at maximum frequency level (50 rad s-1), and apparent viscosity at minimum shear rate (0.1 s-1) of mixes and texture of frozen foams were related. Glass transition temperature of mix containing matodextrin, arabic gum, and commercial ice cream mix were found to be -27.54, -30.94, and -30.41° C, respectively. The results of this study could help to understand more about the functionality of hydrocolloids in frozen desserts.
Session 36G, Refrigerated & Frozen Foods: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |