EFECTO DE PRETRATAMIENTO MECÁNICO SOBRE LA DEGRADACIÓN DE ÁCIDO ASCÓRBICO EN FRUTOS DE LA Rosa Rubiginosa SECADOS CON AIRE CALIENTE

OHACO ELIZABETH H, MABELLINI ALEJANDRA, MARQUEZ CARLOS A, DE MICHELIS, ANTONIO, LOZANO, JORGE E

Congreso; VIII Congreso Iberoamericano de Ingeniería de Alimentos; 2011

The Rose Hip fruits (Rosa Rubiginosa) have a high ascorbic acid content, between 500 and 2200 mg by each 100 g of fresh fruit; which undergoes a partial degradation during the drying with hot air. The effect was evaluated that has the application of a physical treatment (perforated) previous to the drying of these fruits on the ascorbic acid content, and kinetic one of degradation was determined its. The pre-treatment consisted of making three superficial perforations of 1mm by fruit. The drying took place in an experimental equipment, with a speed of air of 5m/s, 5% of relative humidity, and to different temperatures: 50, 70 and 90¨¬C, comparing with samples without treatment. As much the perforated fruits as the whole numbers follow a kinetic one of first order. The energy of activation was determined by the method of a single step, being of 73,76 kJ/mol K for the whole fruits and of 40,35 kJ/mol K for the perforated fruits. Although the perforated one of the fruits demonstrated to be effective for the reduction of the time of dehydration, is not managed to preserve of better form the ascorbic acid content. The degradation of ascorbic acid during the drying behaves different in the sample witness and the perforated one, nevertheless in the adimensional humidity rank (X*=0, 2- 0,1) the final ascorbic acid content does not present a significant difference (ANOVA, ¥á= 0,05).