Efeito do congelamento ultrarrápido sobre as características físico-químicas e sensoriais de polpa de umbu (Spondias tuberosa Arruda Câmara) durante a armazenagem frigorificada.

Abstract

Ripe umbu pulp has been submitted to three initial fieezing methods, at -22,6°C, -110°C and at-196°C during a period of 180 days of freezing storage. Freezing a cooling kinetic have been determined, physical ehemical and sensory altemations. For the frozen pulp at -22,6°C the cooling, crystallization and poet-freezing phases obtained a time o f around 1.200, 3.000, and 10.200 seconds respectively. For the írozen pulp at-196°C, this time was 70,20 and 235 seconds respectively. The freezing methods didn't interfere on the ascorbic acid stability. The acid leveis present an increasing trend along storing. Reducer, non-redueer sugar and totais have been kept stable in a general way and haven't suffered influence from freezing methods. There has been a trend to increase soluble solids of umbu pulp during freezing storage, for the there initial freezing methods. pH has been stable and hasn't suffered influence from freezing methods. Sensory analysis has showed a preference among tasters. About appearance for írozen pulp at -110°C and at -196°C in relation to freezing in a conventional freezer at -22,6°C, this preference leaning to disappear at the end of the period. About smell, color and taste, ali treatment obtained equal preference among the tasters.