We think of peanuts as nuts, and for all culinary, research and nutritional purposes they are. But they aren’t a typical “nut” – botanically a fruit whose ovary becomes hard at maturity. This is because along with peas, beans and lentils, they belong to the legume family, whose members produce those familiar pods typically with one to twelve seeds and whose root nodules are home to the helpful nitrogen-fixing Rhizobium bacteria.
Peanuts (also called groundnuts) are the seeds of Arachis hypogaea and originally came from South America. The earliest evidence of people tucking into them as a food crop (along with squash, beans, quinoa and coca) comes from Nanchoc Valley in northern Peru where macro and micro-fossils (from the calculus of human teeth) suggest they were part of the local diet between at least 9500 and 7000 BP. They arrived in Europe with the conquering Spaniards at the end of the fifteenth century and then speedily made their way around the world to Asia, Africa and North America.
Dr George Washington Carver is considered by many to be the father of the peanut industry in the US. He began his peanut research in 1903. He suggested to farmers that they rotate their cotton plants (which deplete the nitrogen in the soil) and cultivate peanuts which puts it back.
With their protein, fibre, unsaturated fats, vitamins, minerals, trace elements and phytochemicals, these popular nibbles pack a nutritional punch. They are also rich in substances considered protective for the heart: an amino acid (building block of protein) called arginine; vitamin E, folate, copper (a mineral) and plant sterols.
What about aflatoxin? Processed peanuts are quality-controlled for the presence of fungus that produces a toxin called aflatoxin. Because peanuts in the shell are not screened, throw away any mouldy ones.
What about peanut allergy? This is an increasingly common food allergy especially in children. One-third of all peanut-allergic people are also allergic to tree nuts such as brazil nuts, hazelnuts, walnuts, almonds, macadamia nuts, pistachios, pecans, pine nuts and cashews. See Read More for fact sheet sheet.