Food Biochemistry and Food Processing

530 Part V: Fruits, Vegetables, and Cereals

most popular freezing media. From the vacuum
tank, the apple slices pass through an IQF freezing
unit where the slices are individually frozen. From
the freezing unit the slices are filled into tins or poly-
lined boxes and stored frozen at 17°C or below.
Dehydrofrozen apple slices are dehydrated to less
than 50% of their original weight and then frozen.

The dehydrofrozen slices are packed in cardboard

containers or large metal cans with polyethylene lin-

ers and rapidly frozen before storing. Frozen slices

are thawed and then soaked in a combined solution

of sugar, CaCl 2 , and ascorbic acid or bisulphite. For

fresh and refrigerated apple slices the use of 0.1–

0.2% calcium chloride and ascorbate protects apple

Figure 22.6.Apple processing flowchart.