Osmotic dehydration of physalis (Physalis peruviana L.): Evaluation of water loss and sucrose incorporation and the quantification of carotenoids

Abstract

The rapid growth in demand for physalis production is associated with its nutraceutical and medicinal characteristics. However, one aspect that hampers its commercialization is the high perishability. In present work it is proposed to submit Physalis peruviana L. for osmotic dehydration, to evaluate the effects of temperature (40–70 °C) and osmotic sucrose solution concentration (40–70 g 100 g−1 solution). Moisture content and total sugar content analysis were performed along the osmotic dehydration process and the total content of carotenoids was analyzed for the fresh fruit and after 10 h of processing. Water mass diffusivity ranging between 1.4–2.9 × 10−10 m2 s−1 and the effective mass diffusivity of sucrose ranged from 0.7 to 1.1 × 10−10 m2 s−1. Among all conditions studied in the experimental design, the osmotic dehydration was more efficient when performed at a temperature of 70 °C and an osmotic solution concentration of 70 g 100 g−1 of solution. In these conditions, there was the highest water loss and a statistically significant reduction in the water activity of this fruit. However, the greatest loss of total carotenoids (approximately 50%) was observed. Under this experimental condition, the tissue matrix of physalis suffered structural changes, as proven through scanning electron microscopy analysis.