Influence of cold-storage conditions on the quality of unshelled walnuts
Abstract In this work the influence of cold-storage conditions on unshelled walnut quality is studied. Quarterly, over a period of one year, the evolution of different walnut quality parameters has been analysed (kernel and whole walnut water content, faulty fruit presence, kernel colour, oil-free acidity, oxidative stability of the oil and fatty acids composition), in walnuts stored under two relative humidity conditions (40% and 60%) and three temperatures (3°C, 7°C and 10°C). The assays have been repeated for two consecutive years. It was observed that the whole walnut quality was maintained, for a period of at least 12 months, at 10°C and relative humidity conditions of 60%. With walnuts, cold storage at 40% relative humidity does not improve the final quality of the product, and causes a significant weight loss of dehydration. The tendency of the walnut kernel to darken depends on the variety and harvest or year.