Development and sensory evaluation of osmotically dehydrated guava

Abstract

Despite being a fruit available throughout the year in the irrigated regions of the different regions of the country, guava shows great post-harvest losses associated with its rapid ripening, requiring the application of processing techniques that reduce the loss of this fruit. The objective of this work was to study the mass transfer process during the osmotic dehydration of guava slices and evaluate the sensory parameters of the dried guava obtained at different osmosis temperatures and sucrose concentrations. Guava cv. Paluma slices (3.0 × 2.0 × 0.9 cm) were subjected to osmotic dehydration in sucrose syrup at 40 °Brix, 50 °Brix and 60 °Brix combined with temperatures of 30 °C, 40 °C and 50 °C using a factorial central point design. The osmotic pre-treatment was complemented by convective drying at 60 °C and the dried guava slices studied with respect to mass transfer during the process of osmotic dehydration followed by a sensory evaluation. It was found that the maximum mass transfer occurred during the initial 4 hours of dehydration and the concentration of sucrose had the greatest influence in reducing the amount of water and increasing the incorporation of solids. The sensory assessment parameters demonstrated that the product most preferred by the panellists was that obtained with lower sucrose concentrations for the attributes of appearance, colour, texture and flavour. No significant differences were observed between the scores awarded by the panellists for the attribute of odour. The sensory profile applied showed good acceptance of the osmotic pre-treatment when compared to the in natura fruit dried only by convective drying.

Keywords:
Mass transfer; Osmotic dehydration; Sensory acceptance