Source: Ref. 10.

ity to the final stage where it is conveyed slowly through a 70-80% RH zone to cool to temperatures low enough to prevent thermal stress cracking. About 1 h is required. An additional 0.5-1.0% moisture loss occurs in this stage. The major advantages of this process are time, space, and labor savings.

Another drying process of interest is a system for the production of bread crumbs from bread dough. The fresh dough is extruded into one end of an 80 kW, 2450 MHz microwave-hot air tunnel where it is baked and dried so that the finished product can be cooled and ground into bread crumbs.

Some snack food items are being produced in a 240 kW, 915 MHz baking-drying unit. The dough is extruded as parallel strands onto a 5-ft-wide belt that passes through 12 independent sections, each with 25 kW of microwave power and an independent air system, where it is puffed, baked, and partially dried.

Microwave vacuum drying of fruit juice concentrates has been successfully demonstrated. In this process the concentrate is pumped into the vacuum chamber onto a conveyor belt where it foams under the effect of microwave energy and reduced pressure to a thickness of80-100 mm. The product dries to a meringuelike condition, is crushed, scraped, and brushed from the belt into a receiver that is isolated from the vacuum chamber. A 48 kW, 2,450 MHz system will dry concentrate to 2% moisture in about 40 min at a rate of 50 kg/h.

Berry Boosters

Berry Boosters

Acai, Maqui And Many Other Popular Berries That Will Change Your Life And Health. Berries have been demonstrated to be some of the healthiest foods on the planet. Each month or so it seems fresh research is being brought out and new berries are being exposed and analyzed for their health giving attributes.

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