Abstract

Nuts, hard-shelled seeds enclosing a single edible oily kernel, are generally used for human consumption. Nuts may be consumed as shelled whole nuts or, after blanching, roasted. Roasted nuts may be either eaten or ground into nut butters. Peanuts which contain excessive levels of aflatoxin are generally extracted for peanut oil. Production processes are outlined for nut salting, defatting, and the making of peanut butter. With the exception of peanuts, most commercially important nuts are borne on trees. As a whole, nuts have high oil and protein contents and a low percentage of carbohydrate. Approximate composition in terms of amino acid, fatty acid, vitamin and carbohydrate levels are tabulated for selected nuts and nut products. Because of the high oil content of nuts, rancidity is one of the first signs of deterioration in nuts. Optimal storage conditions are discussed as are coatings and antioxidants to delay the onset of rancidity. Non-edible uses of nuts are as a source of quick drying oils, activated charcoal, dyes, and tannins. Production data are given for the principal edible nuts: almonds, cashews, Brazil nuts, English walnuts, filberts or hazelnuts, macadamia nuts, pecans, and pistachios.