Preservation of fresh walnut halves for use in e.g. cheese, pastries, confectionery and dietary foods

摘要

Preservation of fresh walnut halves comprises: (i) selecting husked, fresh, dried harvested walnuts; (ii) spraying with an aq. food grade acid soln. such as citric acid; (iii) freezing immediately by spraying with liq. N2 at -80 to -100 deg C; and (iii) maintaining the frozen walnuts in a cold unit. Batches of 30-50 kg walnut halves are pref. continuously passed through a citric acid mist in which they are maintained until covered with a film of the soln. Freezing involves contact with a refrigerant fluid for 1 min. and storage at below -18 deg C.