Abstract:

Prickly pear (Opuntia-ficus indica L.) grows in arid and semi-arid areas and show good nutritional and medicinal characteristics. Fruit consumption is limited by short harvesting season and shelf life. Drying may resolve such issues. The objective of the present work was to evaluate the effect of different types of dehydrated fruits (dehydrated bars, dehydrated slices or powder) on the storage ability of 2 ecotypes of Opuntia-ficus fruit harvested in South of Portugal (“Orange” and “Green”). Fruits were prepared without peel and cut in slices or mixed as pulp then dried at 60°C. Afterwards, slices were stored, and pulp prepared as dehydrated bars or powder, then stored at room temperature for 9 months. Initially and at the end of storage period, colour (CIELab), soluble solids content (SSC), titratable acidity, water activity (a_w), total fibre content, ash content, protein content, phenolics, flavonoids, tannins, betalains and antioxidant activity were determined and as well microbial contamination and sensory panels. Prickly pear dried food products showed very good nutritional quality attributes. Apart from colour, there were no significant differences between ecotype quality. The fruit powder was lower in SSC than the fruit bars and higher in bioactive compounds (total phenols, tannins, flavonoids and betalains) and antioxidant activity. Dehydrated sliced fruits, although they are nutritionally rich, do not seem to be commercially viable because they contain too many seeds in the opinion of the taste panel. Fruit bars are a good source of energy and with good overall acceptance by the taste panel. The quality was maintained for all treatments up to 9 months storage with microbial development under the standard limits.