Efeitos da aplicação de calor e da radiação UV-C na qualidade de polpas refrigeradas de hortofrutícolas

Mestrado em Engenharia Alimentar - Qualidade e Segurança AlimentarPasteurization conditions, optimized by response surface methodology, were dependent upon the tested formulations: P_Amarela [Rocha pear (50%): Pineapple (50%)] e P_Vermelha [Rocha pear (66%) Strawberry (30%), Beetroot (4%): Lemon juice (1.5%)], for the timetemperature binomials of 95 ºC/10min and 90 ºC/10min, respectively. After processing, pasteurized pulps showed significant levels of reduction of mesophilic load (> 2 Log cicles) as well as POD inactivation (>99%) without causing changes in colour, pH, soluble solids content and phenolic content. These results were validated for P_Amarela and P_Vermelha, where again high decontamination levels (4 Log cicles) and POD inactivation, were achieved gathered with high sensorial acceptance. The levels of soluble solids content, pH, consistency index and pulp colour did not significantly change during 30 days (5 °C), irrespective of evaluated formulation. Maintenance in total phenolic content was observed in P_Amarela throughout storage while P_Vermelha showed a decrease for the initial 7 days to about half the initial content, maintaining these levels till the end of storage (p>0.05). The tested doses of UV-C radiation, from 0.5 to 16 kJ/m2, did not promote the expected decontamination effects and/or of enzymatic inhibition (POD)