Rheological behavior of mixed drink of annona and milk

Abstract

ABSTRACT:In this study the rheological behavior in different temperatures (0; 6; 18 e 24 °C) and physicochemical parameters of integral annona (Annona squamosa) pulp and the annona pulp with milk in different percentages pulp/milk (75g of annona pulp/25g of milk, 50g of annona pulp/50g of milk, 25g of annona pulp/75g of milk) have been availed, in order to verify the effect of temperature and pulp concentration in the rheological behavior of these beverages. To obtain the rheological parameters a concentric cylinder rheometer has been used and the rheograms were analyzed using the Ostwald-de-Wael (power Law) and Herschel-Bulkley models. The physicochemical parameters (sugars, pH, ash, acidity and soluble solids) were determined in order to establish correlations with the rheological behavior. Finally, the best results had been obtained using the Herschel-Bulkley model; the low values for the behavior index (n <1) obtained confirm the pseudoplastic behavior of all samples.KEYWORDS: fruit, rheology, agro-industry, processing. COMPORTAMENTO REOLÓGICO DE BEBIDA MISTA DE PINHA E LEITERESUMO: Estudou-se o comportamento reológico em diferentes temperaturas (0; 6; 18 e 24 °C) e os parâmetros físico-químicos da polpa de pinha (Annona squamosa) integral e também da polpa de pinha com diferentes percentuais de leite (75g de polpa de pinha/25g de leite; 50g de polpa de pinha/50g de leite; 25g de polpa de pinha/75g de leite), com o intuito de verificar o efeito da temperatura e da concentração de polpa no comportamento reológico desses blends. Para a obtenção dos parâmetros reológicos, foi utilizado um reômetro de cilindros concêntricos. Os parâmetros físico-químicos das formulações pH, acidez total titulável, sólidos solúveis totais, sólidos totais e cinzas foram determinados com o intuito de correlacioná-los com o comportamento reológico obtido. Os reogramas foram analisados utilizando os modelos de Ostwald-de-Wael (Lei da Potência) e Herschel-Bulkley. Os melhores resultados foram obtidos usando o modelo de HerschelBulkley, e os baixos valores obtidos para o índice de comportamento (n<1) confirmam o comportamento pseudoplástico de todas as amostras.

Comparative Physicochemical Properties and Antioxidant Activity of Dietary Soursop Milkshake

“…The total soluble solids observed in fresh extract (SFE) was higher than the value of 12.83 • reported for soursop pulp by Orsi et al [27], and this may be attributable to the level of fruit ripeness and geographical variation. The present result is similar to the finding of Duarte et al [22], who reported a value of 23.67 • Brix for a blend of 75% Annona pulp and 25% milk. However, Bajwa and Mittal [28] reported a lower brix value (13.9 • ) for mango flavoured milk drink.…”

“…Yapo et al [20] and Islam et al [21] also reported similar values for pineapple juice and mango juice, respectively. An increase in pH was reported for sugar-apple pulp substituted with milk [22]. The pH values observed for the milkshakes were higher than those reported by de Moura et al [23] for a milk drink flavoured with mangaba pulp (4.03-4.12).…”