29C-29 |
Rheological properties of "chocolate"milk beverage from cupuassu |
S. C. S. LANNES, Biochemical-Pharmaceltical Technology Dept./Pharmaceutical Faculty, University of São Paulo, Av. Prof. Lineu Prestes, 580/Cidade Universitária, São Paulo-SP, CEP 05508 90, Brazil and M. L. Medeiros, Biochemical-Pharmaceutica Dept./Pharmaceutical Faculty, University of São Paulo, Av. Prof. Lineu Prestes, 580/Cidade Universitária, São Paulo-SP, CEP 05508900, Brazil. Cupuassu is one of Amazonian’s most popular fruit species, commanding excellent prices during its harvest season. Its developing market outside Amazonia is supplied with frozen pulp. Cupuassu’s seed is very rich in fats (± 60% dry weight) and after treating this could provide a powder similar to cocoa, which could be used to produce a cupuassu powder “chocolate”. Our objective was to produce cupuassu powder “chocolate” processed by spray dryer to promote instantisation, dilute in milk and to determine the flow properties, obtaining models parameters of Newton, Ostwald and Bingham equations for these beverages. A mini spray dryer Büchi 190 was used to instantised the cupuassu “chocolate” powder prepared. A coaxial cylinder rheometer (Rheotest RN 3.1), a thermostated bath (25 and 40˚C), and Rheotest Software were used. Experimental data were fitted to Newton, Ostwald, Bingham and Casson models. Experimental results, obtained at 25 and 40˚C, fitted mostly the Ostwal, Bingham and Casson models, with R2 ≥ 0,99. The Newton model has R2 ≥ 0,93. At 25˚C, as expected, viscosity of samples was higher and pseudoplasticity increased (n values were lower). The results obtained were satisfatory, due to the complete instantisation of the product after processing. Cupuassu powder does not disperse readily in water owing to its oil content. Consequently, a form of cupuassu with the oil removed is need to produce an acceptably instant drink. Cupuassu chocolate drink powder is a mixture of cupuassu powder, sugar, flavour and other ingredients of formulation. The product was processed by spray-dryer, leading a dry, pulverized and instantaneized product. The rheological data of the prepared beverages give a information about the process and which rheological models could be adapted to these products.
Session 29C, Food Engineering: Rheology and texture
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