Processamento e estabilidade de uma bebida de caju e yacon durante o armazenamento sob refrigeração

Abstract

The objective of the present study was to evaluate the stability of a beverage produced with cashew apple and yacon during refrigerated storage. The beverage, composed of cashew pulp and yacon extract (ratio 1: 1, v / v), was pasteurized at 85 °C for 90 seconds and stored at 5 °C. The following components were evaluated at zero time (after processing and packaging) and every 45 days during the storage period: The bioactive compound contents (ascorbic acid (AA), total extractable polyphenols (PET), total antioxidant activity (AAT), total soluble solids, titratable acidity (AT), pH and colour (L ∗, a ∗ and b ∗). After 225 days of storage, the beverage presented a 22% decrease in AAT as analysed by the FRAP method (Ferric Reducing Antioxidant Power), as well as a drop in the AA and PET concentrations of around 20 and 16%, respectively. The beverage complied with the microbiological standard established by Brazilian legislation for coliforms at 45 °C and Salmonella sp. (absence/25 mL), but after 135 days storage, the beverage had a yeast and mould count greater than 104 CFU/mL. Thus although the beverage presented considerable levels of bioactive compounds and AAT during the 225 days of refrigerated storage (5 °C), it is recommended that it be stored for up to 90 days under refrigeration (5 °C), considering the microbiological, sensorial quality and maintenance of its bioactive components during this period.