Chemistry of Peanut Butter

Peanut butter is consumed in 90 percent of American households, according to the National Peanut Board, at time of publication. The organization also notes that the average American consumes more than 6 pounds of peanuts and peanut butter products each year. With Americans spending nearly $800 million annually on peanut butter, you might be curious to know exactly what is in this popular foodstuff. You might even be surprised to discover that substances other than peanuts may be in this creamy concoction.

Peanuts

• Peanuts, the most important, and the most obvious, ingredient in peanut butter, are not actually nuts at all. Instead, they are classified as legumes and are in the same classification as beans and lentils. Any product labeled “peanut butter” in the United States must be at least 90 percent peanuts. And while they may have "nut" in their name, peanuts contain more protein, niacin, folate and phytosterols, steroid compounds that occur naturally in plants, than any actual nut. Peanuts contain high levels of antioxidants and offer more than 30 essential nutrients and phytonutrients (plant-based nutrients). They are a naturally cholesterol-free food.

Phytonutrients and Antioxidants

• Just like red grapes, red wine and dark chocolate, peanut butter is packed with phytonutrients and antioxidants. The main phytonutrient in peanut butter is a heart-healthy compound called "resveratrol." Resveratrol, which has been linked to anti-aging, is believed to help prevent cancer. Resveratrol might also help reduce the risk of stroke by improving blood flow in the brain by as much as 30 percent.

Monounsaturated Fats

• Peanut butter sometimes gets a bad rap for being a high-fat food, but the majority of that fat is the good heart-healthy kind. Monounsaturated fats, like the oleic acid in peanut butter, which is the same type as in olive oil, are believed to help decrease the risk of cardiovascular disease. In the chemical sense, a monounsaturated fat is a fat that has one double-bonded, or unsaturated, carbon in its molecule. Monounsaturated fats are typically liquid at room temperature but become solid in chilled temperatures. A good example of this is demonstrated in the oil separation of natural peanut butter. When you first open the jar, the oil is pooled at the surface, and you must mix it back into the solid portion; however, upon refrigeration, the oil quickly solidifies to match the consistency of the rest of the mixture.

Hydrogenated Oil

• Certain brands of peanut butter contain an extra ingredient known as hydrogenated oil; small amounts of hydrogenated oils are added to these brands to help prolong their shelf-life. When added to peanut butter, hydrogenated oil also keeps the natural oil from separating, preventing the mixture from becoming gritty or pasty. A debate has been going on over the years as to the effect of hydrogenated oils (trans fats) on health, as such acids are thought to be a cause of atherosclerosis, which can lead to such illnesses as coronary heart disease and stroke.