Quality of York Imperial apples as affected by the use of corn syrup in the freezing media
The purpose of this study was to investigate the effects of freezing on apple slices in a sucrose media with two levels of replacement of regular and high conversion and commercial corn syrups. The dextrose equivalent of the syrup, drained weight, soluble solids of the syrup and fruit, the relationship of cellular structure and firmness and acceptability as judged by a taste panel were studied after 3 weeks and 3 months storage.
Objective measures included drained weight, soluble solids, reducing sugar content of the syrup, Alla-Kramer shear press readings of firmness and microscopic examination of the apple tissue. Color, flavor, sweetness, firmness and overall acceptability of the apple slices were measured subjectively by a taste panel.
The results obtained indicated that there was a movement of water out of the apple tissue, the amount of which was dependent on the dextrose equivalent of the syrup. There was also some slight migration of sugars into the apple slices, after cellular damage occurred. As the dextrose equivalent of the freezing media increased there was a decrease in drained weight and syrup soluble solids and an increase in fruit soluble solids, browning, cellular damage and firmness.
The addition of" 25% commercial corn syrup to a 40% sucrose syrup would be highly recommended as a freezing media for York Imperial apples because of the increase in drained weight. slight increase in fruit soluble solids, less cellular damage and the retention of a more natural color.