Minimally Processed Fresh-Cut Peach and Apricot Snacks of Extended Shelf-Life by Combined Osmotic and High Pressure Processing

Abstract

The quality and preservation of fresh-cut fruits can be improved by applying mild, non-thermal pre-treatments, such as osmotic dehydration and high hydrostatic pressure. The aim of this study was to model the effect of the combined application of these two technologies, on the main quality attributes of peaches and apricots (sensory indices, color, texture) and microbial stability during subsequent refrigerated storage. Fresh-cut fruit spheres were osmotically treated at preselected osmotic conditions (45 °C for 45 min, wfruit/wsolution = 1/5) (OD samples) and by in-pack cold-pasteurization (HP: 600 MPa/25 °C/5 min) (OD/HP samples) and stored at isothermal (5 to 15 °C) and dynamic temperature conditions (Teff = 7.8 °C). Kinetics of quality indices’ change was studied and modeled as a function of storage conditions. Shelf-life was significantly prolonged for OD/HP samples, at 309 and 320 days at 4 °C, for peach and apricot, respectively, compared to approximately 68-86 days, for OD samples, limited due to microbial growth. In any case, shelf-life extension is significant, in both pretreatments (OD and OD/HP), when compared to the respective non-treated samples, with an estimated chill storage durability of 5–7 days. Apricots (both fresh and pre-treated) were softer compared to peaches. HP effect on osmosed fruit tissue was considered as positive leading to a significant increase of hardness. OD/HP samples were characterized by dark yellow to light brown color, while OD samples by vivid yellow to orange color, both evaluated positively by the sensory panel. Both pre-treated samples were described to retain to a significant level, the fresh-like fruit characteristics (aroma/flavor).