Processamento mínimo em goiabas 'Paluma' e 'Pedro Sato': 2. Avaliação química, sensorial e microbiológica

Abstract

Two cultivars of guava fruit, and Paluma, were studied. They were both obtained from a commercial orchard, at the maturation stage of ready for harvest, corresponding to a dull-green coloration and considered perfect for eating. The fruits were initially immersed in a solution of sodium hypochlorite (150mg.L-1 chlorine) for 5 min, for superficial disinfection. Trained personnel, using adequate protection and disinfected equipment, peeled the fruits, cut them longitudinally down the middle and removed the pulp with the seeds, at a temperature of 12°C. After rinsing with chlorinated water (20mg.L-1 chlorine) the fruit halves were packaged in polyethylene terephthalate containers. These units were stored at 3°C for 10 days. Microbiological analyses were performed throughout the study. Chemical analyses of the products were carried out to determine the contents of lignin, ascorbic acid, total titratable acidity, total soluble solids and the percentage of solublized pectin, in addition to testing for the sensory variables of texture, flavor and preference. For both cultivars the texture became more fragile and the ascorbic acid content reduced during the storage period. During this period there was an increase in lignin content and no change in total soluble solids (TSS) content, total titratable acidity (TTA) and the TSS/TTA ratio. The product of the Pedro Sato cultivar showed less loss of texture than that of 'Paluma,' considered by the tasters as the one with more flavor and thus being more preferred. Because of the hygiene precautions taken during the processing of the product, it showed a lower microbial contamination (< 103 CFU.g-1), in all the tests conducted.