maybe already rancid at the time of purchase. Consequently, pine nuts are often frozen to preserve their flavor. European pine nuts may be distinguished from Asian ones by their greater length than girth; Asian pine nuts are stubbier, shaped somewhat like long kernels of corn. The American piñon nuts are known for their large size and ease of shelling. In the United States, Pinus edulis, the hard shell of New Mexico and Colorado, became a sought-after species due to the trading post system and the Navajo people who used the nuts as a means of commerce. The Italian pine nut (P. pinea) was brought to the United States by immigrants and became a favored treat along the East Coast in the early 1930s, when bumper crops of American pine nuts were readily available at low prices. Nutrition When dried for eating, pine nuts are 2% water, 13% carbohydrates, 14% protein, and 68% fat (table). In a reference serving, dried pine nuts supply of food energy and are a rich source (20% or more of the Daily Value, DV) of numerous micronutrients, particularly manganese (419% DV), phosphorus (82% DV), magnesium (71% DV), zinc (67% DV), copper (65% DV), vitamin E (62% DV), vitamin K (51% DV), and the B vitamins, thiamin and niacin (29–35% DV), among others (table). Culinary uses Pine nuts have been eaten in Europe and Asia since the Paleolithic period. They are frequently added to meat, fish, salads, and vegetable dishes or baked into bread. In Italian, they are called pinoli (in the US, they are often called pignoli, but in Italy, pignolo is actually a word far more commonly used to describe a fussy, overly fastidious or extremely meticulous person) and are an essential component of Italian pesto sauce; the upsurge in the popularity of this sauce since the 1990s has increased the visibility of the nut in America, primarily on the West Coast. Torta della nonna (literally "granny's cake") is a generic Italian dish name that in most families indicates an old family recipe for any cake but often is used for a tart or a pie filled with custard, topped with pine nuts and optionally dusted with icing sugar. Pignoli cookies, an Italian American specialty confection (in Italy, these would be called biscotti ai pinoli), are made of almond flour formed into a dough similar to that of a macaroon and then topped with pine