Are nut seeds, legumes, or fruit? In the culinary world, the answer is “yes” to all three. Although the botanical definition of a nut is quite defined, the culinary use of the word “nut” is rather varied. While almonds, cashews, pistachios, and walnuts are technically seeds, and peanuts are really a legume. On the other hand, hazelnuts are considered a true botanical nut.
Botanically speaking, nuts are a composite of seed and dry fruit found inside of a hard outer shell. For culinary purposes, what are considered "nuts" share the same characteristics: oily, tender flesh surrounded by a hard outer shell. They're used in a variety of recipes, from baked goods to granola, and offer a quick snack when eaten out of hand.
Nuts are a common snack food and are perfect for traveling. Nuts are often a major component in trail mixes and granola bars. In addition to being eaten whole, nuts are often pureed into “butters” and used as a spread or as an ingredient in dips.
Some nuts, like almonds, are used to produce non-dairy milk substitutes. The nuts are pureed, mixed with water, and then strained to remove the solids. The resulting liquid can be consumed plain or flavored and sweetened to increase palatability.
Nuts can be purchased raw, either in-shell or pre-shelled. Whole nuts with the shell intact are a popular item during the winter months and holiday season. Whole nuts can be stored at room temperature or refrigerated. Regardless of the storage temperature, nuts should be kept away from moisture and heat. Natural nut oils are delicate and can go rancid easily. If a nut has a bitter or off-flavor, it should be discarded.
Shelled nuts can be purchased raw or roasted. Roasted nuts have a deeper, more complex flavor and may also be salted or seasoned with other spices. Nuts can be either dry roasted or roasted in oil, both of which produce a unique flavor and texture in the nut. Shelled nuts also need to be stored away from heat and moisture. Freezing nuts is an option that can dramatically increase their shelf life.
A variety of nuts are made into butters or purees, most notably peanut, almond, and cashew. Nut butter can be stored at room temperature if purchased in a sealed container but should be refrigerated once opened. Freshly ground nut butters should be stored in an air-tight container in the refrigerator.