Drying characteristics of mango slices using the Refractance Window™ technique

Heat Transfer Mechanisms in Conductive Hydro-Drying of Pumpkin (Cucurbita maxima) Pieces

“…2a and 2c). Based on the typical temperature profile at the sample surface during RW drying, as reported by other authors [3,6,13] , there is a zone of initial heating and a stabilization zone (linear) where thermal equilibrium is reached, which is consistent with the results shown in this paper. Stabilization in temperature occurs due to the increased thermal resistance of the dry product layer, allowing the product to dry at moderate temperatures, and no further degradation occurs [7] .…”

“…For clarity in reading the data in Figure surfaces. This same behavior has been reported by several researchers for RW drying (with Mylar) of purees, juices, and slices of several fruits and vegetables [2,3,6,20] .…”

“…High temperatures recorded for a product under any type of drying could lead to greater moisture losses. However, that was not observed in this study or by Ochoa et al [3] .…”

“…Ochoa et al [3] , during RW drying of mango slices of 1 mm thickness with the water temperature at 90°C, reported a temperature at the sample surface near 72°C that is maintained until the end of drying, 60 min later. Meanwhile, in convective air-drying at 90°C, the sample temperature shows a rising trend and reaches 80°C after 60 min.…”

“…Refractance Window drying (RW TM ), patented by Magoon [1] and developed by MCD Technologies Inc. (Tacoma, WA), is a method of food dehydration that offers low operating costs with excellent retention of color, flavor and nutrients. The use of this technology has been reported for drying a variety of fruits and vegetables such as strawberry and carrot [2] , mango [3,4] , açai [5] , pumpkin [6] , aloe vera [7] , paprika [8] , potato [9] and tomato [10] . In addition, this drying has gained preference over other techniques and has been successfully used to produce a wide range of other products such as egg mixtures, herbal extracts, seafood, nutritional supplements, dietary and nutraceutical ingredients and food ingredients such as herbs and spices [7,11,12] .…”