Refractance Window drying: Quality retention and energy efficiency

While dehydration is good for removing the harmful bacteria that cause food to spoil, the heat isn’t intense enough to kill those that thrive in raw meat. Be sure to cook any meat to its proper internal temperature using a meat thermometer before drying it. Since dehydrated foods are usually free from added sugars and preservatives, they are a great source of vitamins and minerals.
DETAILED DESCRIPTION A  low profile design air tunnel system and method for providing uniform air flow in a refractance window dryer are disclosed. According to one embodiment, a system comprises a conditioned air supply manifold that provides air into a drying chamber. The system has a drying belt directed through the drying chamber. A feed application tray at a first end of the drying belt applies a liquid to the drying belt. The system has an exhaust manifold located at the first end of the drying belt. SUMMARY A low profile design air tunnel system and method for providing uniform air flow in a refractance window dryer are disclosed.

Reviewers recommended this product for its easy setup, superior performance, and quiet operation. Many customers raved about the results they got with a variety of foods,  including meat, pineapple, and zucchini. Less satisfied consumers said that the product stopped working or cracked over time. Reviewers liked this dehydrator’s even heat distribution, quick-navigation control panel, and easy-to-clean parts. Many were thrilled with their results as well. Low-rated reviews mentioned the control panel malfunctioning and the body not reaching the full range of advertised temperatures.
1 illustrates a cross-sectional view of an exemplary dryer 100 using an air supply manifold 120 that extends across the width of the drying belt 110, according to one embodiment. The dryer 100 includes a cover 101 that provides a cover and headspace Refractance Window Dryer above a drying belt 110 for the dryer 100, an air supply manifold 120 that introduces conditioned air 102 into the dryer 100 and an air outlet exhaust manifold 130. The drying belt 110 floats above a heated medium flowing in a trough 150.

When water is placed over a heating source, infrared energ is transfered throughout the water by convection. The heat energy then radiates from the wanter, primarily through evaporation. •RW dried PJ have antioxidant activity equal or greater than FD and SD samples.
Drying describes a complex heat and mass transfer process of removing moisture from food materials. The final product may be in the form of sheet, flakes, film, powder, or  granules. An additional size reduction step may be involved based on product requirements.

Refractance window drying has found several applications not only in food industries but also in pharmaceutical, nutraceutical, cosmetic and pigment handling industries. The objective of this work is to present the recent trends in refractance window drying of foods with emphasis on the underlying mechanism and effect on product quality. A case study on refractance window drying of mango pulp is presented for improve understanding on the topic. Refractance window drying has the potential to produce high quality dried slices, purees and juices. Research suggests that active aromatic and pigment compounds responsible for characteristic sensory and nutritional attributes can be retained through this technique. Trough 640 may include a single pump or one pump per chamber, according to some embodiments.
Because Refractance Window Drying is a gentler process, it has several advantages over other common dehydration methods like spray drying or freeze drying. The dried food retains all of the nutritional properties of its fresh, raw-food equivalent because it is only briefly exposed to non-damaging temperatures and is never subjected to pressure or shear force. Wherein the conditioned air flows from the conditioned air supply manifold to the exhaust manifold above the belt and in a direction countercurrent to a direction of travel of the product on the belt.
4 illustrates an exemplary side view of a conditioned air supply manifold, according to one embodiment. 2 illustrates an exemplary dryer air supply manifold that distributes conditioned air, according to one embodiment. Another issue with the traditional design was that the perpendicular flow across the belt did not take full advantage of the heat gained from the evaporation of the water from product on belt, consequently requiring significantly more air. The original elevated hood design of the system also resulted in air free flowing high above the belt surface, so any temperature gain was not fully utilized especially given the high CFM flowrate. Jha, R.K.; Prabhakar, P.K.; Srivastav, P.P.; Rao, V.V. Influence of temperature on vacuum drying characteristics, functional properties and micro structure of Aloe vera gel.