ANALYSIS OF PEACH FRUIT SLICES OSMOTICALLY DEHYDRATED WITH SORBITOLAND HOTAIR-DRIED OVER A 55-DAY CONSERVATION PERIOD

SALVAÑAL, LARA; GABILONDO, JULIETA; FRANCESCONI RAFAELA; BUDDE, CLAUDIO OLAF; ANDRES, SILVINA C; GUGOLE OTTAVIANO FERNANDA; SOSA, M; GARITTA, L; PIERONI, VICTORIA; LARA, MARÍA VALERIA; CORBINO, GRACIELA

Congreso; XVIII Congreso Argentino de ciencia y Tecnología de Alimentos. XVIII CyTAL® 2023; 2023

Peach is a subtropical fruit with a fleshy pulp and a delicate aroma. It’s the third more commercialized fruit around theglobe; though, it is perishable having a short shelf life. Different strategies are currently used to preserve itsnutraceutical properties. Osmotic dehydration (OD) previous heat drying is an emergent procedure which preventsbrowning and the bioactive compound loss due to prolonged heating. While different sugars such sucrose can be usedduring OD, sorbitol is a healthier alternative. Sorbitol is naturally occurring in peach fruit and it has a reduced calorievalue and a very low glycemic index, which make it ideal for diabetic persons and for consumers that are looking for asnack reduced in sugars. Previously, we showed that sorbitol can be used as osmolyte in the OD processing of peachfruit slices, rendering a healthy product. In the current work, we studied the stability over a 55-day period of driedpeach slices which were osmotically dehydrated with sorbitol previous to heat drying. Flordarking peaches from SanPedro, Buenos Aires, were harvested at commercial maturity, disinfected, cut in slices and immersed in ascorbic acidsolution. Then, the slices were incubated at 40°C in a 47° Brix sorbitol solution during 3 hours under stirring.Subsequent, they were dried at 58°C during 4 h until 8.3±1.0 % relative water content (RWC). Slices were stored in aclosed glass container with a supersaturated solution of sodium bromide to generate a 50 % relative humidityatmosphere. The vessel was placed in a dark chamber at 25 ˚C during 55 days. Color, fresh, and dry weights, sensorytexture analysis conducted by a trained pannel, antioxidant activity and total protein, glucose, sucrose, sorbitol,ascorbic acid, total phenolics compounds, carotenoids and flavonoids contents were measured at 0, 15, 33, 41, 49 and55 days after storage.RWC of the stored slices was 27.6±1.3 %, due to humidity equilibration with that of the chamber. Slight changes inslice color were observed during storage, with 55-days stored slices being reddish and less yellow than samplescollected at 0. This data agrees with a 75 % decrease in the carotenoid content in samples analyzed at day 55.Conversely, antioxidant activity, total protein, glucose, sucrose, sorbitol, ascorbic acid, total phenolic compounds, andflavonoids contents, and manual fracture, texture and cohesiveness were constant over time. After 15 days, firmnessand crunchy perception was increased and accompanied with a decrease in oral breakdown. Taking together, osmoticdehydration with sorbitol before heat drying is a plausible option to dehydrate peaches slices and to generate a healthysnack for diabetic consumers that maintains its nutritional properties and bioactive compounds over at least 55 daysafter processing.