Not all peanuts are the same. Currently, there are four different varieties of peanuts in the market: Virginia, Spanish, Runner and Valencia.
Virginia peanuts are most commonly eaten as whole peanuts for snacking, and Spanish peanuts are typically used in candy and confections.
Runner peanuts are used to make most of the commercial peanut butter brands. Runner kernels are very uniform in size, making it easy to roast evenly and make a consistent product. However, these commercial peanut butter brands usually add sugar and hydrogenated vegetable oil to "improve" the flavor and consistency of the peanut butter.
Valencia peanuts on the other hand, have smaller kernels (you can find three or more in each shell). They are sweeter and oilier than Virginia or Runner peanuts, which makes them perfect for all-natural peanut butter. We don't need to add any sweetener or extra oil. Also, they are less likely to contain mold.
Valencia peanuts grow in bushes above the ground, (as opposed to the other peanut varieties, which grow partially buried under the soil), and they are cultivated mostly in New Mexico and the Southwest of the United States. The dry climate and growth habit of the plants, make valencia peanuts less susceptible to aflatoxins (the toxin produced by the Aspergillus mold).
Mold can still grow on any peanut if these are not stored properly. But at East Wind Nut butters, we make sure to always get the highest quality nuts, and we immediately store our peanuts in our climate-controlled warehouse.