Study of Water Distribution, Textural and Colour Properties of Cold Formulated and Air-Dried Apple Snacks

Abstract

Vacuum impregnation is considered a cold formulation technology since it allows the incorporation of a desired functional compound into porous plant tissue without applying any heat. It is widely used in combination with the drying process to obtain added-value snacks. The aim of this work was to evaluate the effect of two trehalose concentrations (5 and 10% w/w) on: (i) the water state and texture evolution during the air drying (50 °C, 8 h) of apple snacks vacuum impregnated with blueberry juice, and on (ii) the colour of the final dried apple snacks. The results of nuclear magnetic resonance (NMR) showed that trehalose affects the water mobility of the samples during drying especially after 200–300 min of drying. In terms of textural properties, trehalose could increase the crispier characteristic of the samples impregnated with trehalose at the end of drying. Significative changes were found in terms of chroma and hue angle.

Home-Drying Operation Effect on Moisture Content, Electric Energy Consumption, Ascorbic Acid, Total Polyphenol Content, and Color of Sliced “Fuji” Apples

“…These authors consider that long drying time at low temperatures could promote color changes associated with browning product formation in apples. Others results showed that drying with hot air causes a significant color alteration of apple slices [ 14 , 33 ].…”

“…The worldwide consumption of dried apples as a snack (slices, cubes, etc.) is popular due to its photochemical components that are beneficial to human health and attractive organoleptic quality [ 13 , 14 ]. Apple drying using home equipment allows the fruit preservation and avoids waste.…”

Effect of the Pulsed Electric Field Treatment on Physical, Chemical and Structural Changes of Vacuum Impregnated Apple Tissue in Aloe Vera Juices

“…Recently the application of juices, both concentrated or diluted, has also been studied. In particular, apples have been enriched with the phenolic compounds from the blueberry juice [12] and grape juice concentrate [13]. In addition, apple juice [14] and mandarin juice [15] were used as a medium for probiotic introduction into the apple tissue.…”