Walnuts from California are available as in-shell and shelled walnuts.
60 % of Californian walnuts are marketed as kernels and are for both the final consumer and for further industrial processing. The nuts are only removed from the store and cracked when there is an order from the buyer. Fully automatic machines crack the nuts. They are then air-blasted to separate the walnut kernels from the shell residue, before they are electronically sorted according to color and size. The remaining pieces of shell are then removed using laser technology.
Walnuts with a perfect shell are predetermined to be sold as in-shell walnuts. Following drying, sizing of the in-shell nut occurs. In-shell walnuts are sized as jumbo, large, medium or baby according to USDA standards.
Find out more on the European Marketing Standard.