Methodology for Direct Contact Freezing of Vegetables in Aqueous Freezing Media

This work treats the freezing of foodstuffs in aqueous media with the intention of reducing the pickup of solute on the solid. Product frozen in 23% NaCl solution (AF 23‐0) was centrifuged, washed, and/or blotted to remove surface adhering freezant. Freezing times of less than 1 min were obtained for peas, diced carrots, snow peas and cut green beans. This corresponded to an estimated surface heat transfer coefficient in the range 50‐150 BTU/hr ft 2 °F. Salt residuals ranged from 0.48% (peas) to 2.2% (carrots) and compared favorably to the values reported for canned and remanufactured products. Preliminary cost analysis indicated competitiveness of the method to air‐blast freezing methods.