Nuts

Shell

The walnut shell is the hard woody case around the Juglans regia kernel. It is not food. It governs storage life, in-shell roasting, and how nuts travel through trade and holiday bowls. Home cooks crack shells for peak freshness; factories crack and aspirate them before packing kernels. Shell fragments are a dental hazard—inspect meats carefully after hand cracking. Clean shells may be composted or used as biomass; never assume every shell is safe fuel for smoking food. English walnut shells are thinner than black walnut shells, which is why table crackers work so well on grocery in-shell stock. Sound shells look dry and closed; holes, soft spots, or musty dust signal insects or mould. Keep shell grit out of flour mills and blenders. The edible value lives entirely in the kernel; the shell only decides how long that value survives oxygen and light.