Links

Tools

Export citation

Search in Google Scholar

Physical properties of mixes to mangaba sherbet ; Propriedades físicas de misturas para sherbet de mangaba

This paper was not found in any repository; the policy of its publisher is unknown or unclear.
This paper was not found in any repository; the policy of its publisher is unknown or unclear.

Full text: Unavailable

Question mark in circle
Preprint: policy unknown
Question mark in circle
Postprint: policy unknown
Question mark in circle
Published version: policy unknown

Abstract

Viscosity, unfrozen water (wnc) and glass transition temperature of the maximally freeze-concentrated material (Tg') of sherbet mixtures and the overrum of the sherbets with different concentrations of guar gum (from 0.2% to 0.5%) and mangaba pulp (21.1%, 25.8% and 28.5%) were evaluated. Apparent viscosity ranged from 85.8 to 286.1 cP, increasing with guar gum concentration and mangaba pulp. Thermal analysis using differential scanning calorimetry of sherbets mixture showed that wnc was from 12% to 20%, decreasing with the increasing of mangaba pulp concentration. The Tg' ranged from -57.65oC to -53.45oC and was not different between the samples. The overrum was from 20.1% to 40.59%. Sherbets containing the same pulp concentration presented different values of this variable, however a relationship between the increasing of guar gum concentrations and the air incorporation was observed only for sherbets with 25.8% of mangaba pulp. The stabilizer modified the viscosity of the mixture and overrum and the pulp concentration influenced thermal properties. Higher overrum is better for product smoothness. Higher pulp concentration decreases the wnc so, the product concentrates less water available to form great ices during the changes in the temperature which may cause losses in the product quality. ; O objetivo deste trabalho foi avaliar a viscosidade, a quantidade de água não congelada (wnc) e a temperatura de transição vítrea da fração maximamente crioconcentrada (Tg') de misturas para sherbet, e a incorporação de ar (IAr) dos sherbets, com diferentes concentrações de goma guar (0,2% a 0,5%) e polpa de mangaba (21,1%, 25,8% e 28,6%). A viscosidade aparente variou de 85,8 a 286,1 cP, aumentando com as concentrações de goma guar e mangaba. As análises térmicas com calorímetro diferencial de varredura mostraram que a wnc variou entre 12% e 20%, diminuindo com o aumento da concentração de polpa. A Tg' variou de -57,65oC a -53,45oC e não apresentou diferença entre as amostras. A IAr foi de 20,01% a 40,59%. Sherbets com a mesma concentração de polpa apresentaram valores diferentes desta variável, mas uma relação entre o aumento da quantidade de goma guar e maior IAr foi observada somente para os sherbets com 25,8% de polpa. O estabilizante interfere na viscosidade da mistura e IAr, e a concentração de polpa influencia as propriedades térmicas. O aumento de IAr proporciona melhor maciez ao produto. Maior quantidade de polpa diminui a wnc, assim o produto terá menos água disponível para migrar e formar cristais de gelo maiores durante as oscilações na temperatura, diminuindo a qualidade do produto.