Effect of dehydration temperature on physico-chemical properties and antioxidant capacity of glodenberry (Physalis peruviana L.)

Jessica Lopez1, Antonio Vega-Galvez1, Maria Jose Torres1, Roberto Lemus-Mondaca1, Issis Quispe-Fuentes1, Karina Di Scala2*
Health-conscious consumers prefer a nutritious diet with an increase in fruit intake because of their bioactive compounds. Dehydration is widely used to prolong fruit shelf life. This study researched the effect of convective dehydration on physico-chemical properties, color, vitamin C, β-carotene, total phenolic content (TPC), flavonoids, and antioxidant capacity during dehydration of goldenberry (Physalis peruviana L.) fruits in the 50 to 90 ºC temperature range. Chromatic parameters (L*, a*, and b*) as well as Chroma and hue angle were affected by drying temperature, which contributed to fruit discoloring during this process. Total phenolic content, flavonoids, and β-carotene increased from 321.05-356.68 mg gallic acid 100 g-1 DM, 99.25-144.29 mg quercetin equivalents 100 g-1 DM, and 722.30-783.16 mg 100 g-1 sample, respectively, at 90 ºC. Radical scavenging activity showed higher antioxidant activity at high temperatures than low temperatures. Both vitamin C content and TPC decreased as air-drying temperature decreased. A high correlation was observed between fruit TPC and flavonoids with antioxidant capacity. Based on these results, this fruit has potential for the development of new functional products.
Keywords: Antioxidant characteristics, bioactive compounds, functional food.
1Universidad de La Serena, Departamento de Ingeniería de Alimentos, Av. Raúl Bitrán s/n 599, La Serena, Chile. 2Universidad Nacional de Mar del Plata, Facultad de Ingeniería, Juan B. Justo 4302. Mar del Plata 7600, Argentina. *Corresponding author (kdiscala@fi.mdp.edu.ar).