processing the peanuts

BASIC PEANUT BUTTER RECIPE

2 cups (300 grams) unsalted shelled peanuts

1/4 to 3/4 teaspoon kosher salt

1 to 2 teaspoons honey

1 to 3 teaspoons peanut or vegetable oil, if needed

DIRECTIONS

Heat oven to 350°F. Add the nuts to a round or square cake pan (or rimmed baking sheet). Roast nuts for 3 minutes, shake pan then roast another 3 to 5 minutes or until the nuts are lightly browned and smell nutty. Let cool until you can handle them.

If you are making crunchy peanut butter, add 1/3 cup of the roasted peanuts to the bowl of a food processor. Pulse 6 to 8 times, or until the peanuts are chopped into very small pieces. Transfer chopped peanuts to a bowl and reserve for later.

Add the roasted peanuts to the bowl of a food processor. Process 1 minute then scrape sides of the bowl with a rubber spatula. Process another 2 to 3 minutes until the peanut butter is shiny and smooth. Add your desired amount of salt and honey then process until combined. Check the consistency, if it seems too thick, add oil, a teaspoon at a time, until you are happy with it. For crunchy peanut butter, stir in the reserved peanuts1.

A Brief History of Peanuts & Peanut Allergies

A peanut dominant recipe, like this one, may sound appetizing and make your mouth water upon imaging the sweet, yet salty, smell of peanuts roasting in the oven. However, for many individuals, this smell is not only off-putting, but also deadly. In the US alone, 0.6-1.0% of the entire population has a peanut allergy. This means that at Colby College, a campus of around 2000 students, 12- 20 students would likely be allergic to peanuts, given this statistic. The interesting and complex history of both peanuts and peanut butter throughout recent years will be discussed in how it relates to current nutritional and dietary studies, especially in regards to peanut allergies2.

raw peanuts

Peanuts are part of the legume family and make up a large portion of the worlds crop production, especially in India, China, the US, Africa and Europe. Peanuts are largely popular in the US, where peanut butter is common in many diets. There are two main types of peanuts grown, including bunch/erect, that grow upright, or runners/prostate, which are distributed along the ground. But within the food production there are four main peanut distinctions; Virginia, Runner, Spanish, and Valencia, which differ in their origin, season, and nut phenotype. It is also important to note that peanuts are not actually tree nuts, rather they are groundnuts. Interestingly enough, peanuts are self-pollinating with flowers that are above ground, even though the peanut itself grows underground2.

Peanuts are believed to have originated early in 2000 B.C. in Peru. The majority of the peanuts that reached the US arrived via the slave trade, beginning in Africa, but before this, peanuts were already present on US soil (most likely from Mexico, South or Central America). Peanuts were initially grown as a food source for livestock that could quickly fatten up farm animals, such as pigs, turkeys, and chickens. Peanuts didn’t begin to gain popularity for human consumption until the US Civil War, during which, George Washington Carver found many uses for peanuts. In Europe, a huge market for peanut oil developed, arising from an inability to meet the high demand from the market for olive oil, since peanuts are able to store oil, rather than starch, like in most legumes2.

diagram of peanut plant

Although a market for peanuts had arisen, they proved to be slightly difficult to grow. In fact, about 25% of all peanut crops are lost each year due to a variety of plant disorders. Two common peanut pathogens are Sclerotina minor, which causes sclerotine blight, and Cercospora arachidicola, which causes early leaf spot. Herbicides can be used to control these diseases; however, this treatment is not always effective because of high levels of resistance. Peanuts grow best in hot climates that experience both wet and dry seasons. When growing, the addition of calcium sulfate is essential since without it, the development of peanut fruits is greatly affected. Also, peanuts are typically grown as part of a crop rotation, alternating with other crops every three years in order to decrease the likelihood of soil depletion. When harvesting, only about 15% of peanut flowers actually produce fruit and of the fruit harvested, only 70% of those picked are actually mature at the time2.

Peanuts have an incredibly high percentage of protein by weight, compared to other foods that are typically considered high in protein. For example, the composition of peanut butter is ~27% protein. Thus, peanuts are prized for their ability to provide an inexpensive, yet high, source of vegetable protein. For example, a single 1oz serving of peanuts has 7-8g of protein, which equates to 11-12% of the recommended daily allowance of protein. As mentioned previously, proteins also have a high fat content, ranging from 44-56% composition and of this, 85% of the fat is unsaturated, with a 2:3 ratio of polyunsaturated to monounsaturated fat. With their high fat content, 75% of calories from peanuts come from fat. Additionally, peanuts are particularly low in sodium, but often times peanuts that are consumed are purchased in a salted form, that have much higher compositions of sodium. As far as the composition of vitamins within peanuts, they are high in magnesium, phosphorous, sulfur, copper, and they also contain high amounts of tryptophan, an amino acid that is converted into niacin2.

fresh peanut butter

Despite the highly nutritious content that peanuts contain, they can also be quite deadly to people who have peanut allergies. Allergic reactions occur when an individual’s immune system reacts strongly to a harmless substance, such as peanuts or other common allergens, by producing large amount of antibodies, also known as Immunoglobulin E (IgeE), to target the allergen. These antibodies, in combination with mast cells and basophils, all work together to produce a heightened inflammatory response. A severe allergic reaction is known as anaphylaxis, or anaphylactic shock, which if often life-threatening, requiring immediate emergency intervention. Common symptoms of anaphylactic shock include itchy hives, swelling of the throat and tongue, shortness of breath, dizziness, headache, nausea, vomiting, and abnormal heart rate3.

Research on developing a peanut vaccine has been ongoing for about twenty years. A study published in the Journal of Allergy and Clinical Immunology last Spring indicates that the reality of this peanut vaccine is now within reach. This research study was lead by Jessica O’Konek at the University of Michigan’s Food Allergy Center. The vaccine that they’ve created works by redirecting the immune system, specifically immune cells, during an allergic reaction to peanuts. The studies in which a vaccine was effective were carried out by using mice with allergies to peanuts as a model organism. Dr. O’Konek explains, “By redirecting the immune responses, our vaccine not only suppresses the response but prevents the activation of cells that would initiate allergic reactions”. More research must continue before the FDA approves clinical trials on humans, but these results are extremely encouraging that creating an allergy vaccine is entirely feasible in the future4.

So next time you’re having a handful of peanuts or a PB&J make sure to keep in mind both the history of peanuts in the US as well as the life-threatening allergy attacks that occur when some people consume them.

Sources: 

Gallagher, Joanne. “How to Make The Best Homemade Peanut Butter.” Inspired Taste – Easy Recipes for Home Cooks, 1 Nov. 2018, www.inspiredtaste.net/21318/how-to-make-peanut-butter-three-ways/.

Kiple, K. F. (2001). The Cambridge world history of food. Cambridge: Cambridge Univ. Press.

Krack Media. “Eating Well: Allergies Quick Facts.” The Peanut Institute, www.peanut-institute.org/eating-well/allergy/quick-facts.asp.

Mostafavi, B. (2018). Study: Vaccine Suppresses Peanut Allergies in Mice. Retrieved from https://labblog.uofmhealth.org/lab-report/study-vaccine-suppresses-peanut-allergies-mice