My Meals are on Wheels

One of America’s Favorites – Peanut Butter

“Smooth” peanut butter in a jar

Peanut butter is a food paste or spread made from ground, dry-roasted peanuts. It often contains additional ingredients that modify the taste or texture, such as salt, sweeteners, or emulsifiers. Peanut butter is popular in many countries. The United States is a leading exporter of peanut butter and itself consumes $800 million of peanut butter annually.

Peanut butter is served as a spread on bread, toast, or crackers, and used to make sandwiches (notably the peanut butter and jelly sandwich). It is also used in a number of breakfast dishes and desserts, such as peanut-flavored granola, smoothies, crepes, cookies, brownies, or croissants. It is similar to other nut butters such as cashew butter and almond butter.

The two main types of peanut butter are crunchy (or chunky) and smooth (or creamy). In crunchy peanut butter, some coarsely-ground peanut fragments are included to give extra texture. The peanuts in smooth peanut butter are ground uniformly, creating a creamy texture.

In the US, food regulations require that any product labelled “peanut butter” must contain at least 90% peanuts; the remaining <10% usually consists of “…salt, a sweetener, and an emulsifier or hardened vegetable oil which prevents the peanut oil from separating”. In the US, no product labelled as “peanut butter” can contain “artificial sweeteners, chemical preservatives, natural or artificial coloring additives.” Some brands of peanut butter are sold without emulsifiers that bind the peanut oils with the peanut paste, and so require stirring after separation. Most major brands of peanut butter add white sugar, but there are others that use dried cane syrup, agave syrup, or coconut palm sugar.

Organic and artisanal peanut butters are available, but their markets are small.

A tractor being used to complete the first stage of the peanut harvesting process

Production process
Planting and harvesting
Due to weather conditions, peanuts are usually planted in spring. The peanut comes from a yellow flower which bends over and infiltrates the soil after blooming and wilting, and the peanut starts to grow in the soil. Peanuts are harvested from late August to October, while the weather is clear. This weather allows for dry soil so that when picked, the soil does not stick to the stems and pods. The peanuts are then removed from vines and transported to a peanut shelling machine for mechanical drying. After cropping, the peanuts are delivered to warehouses for cleaning, where they are stored unshelled in silos.

Shelling
Shelling must be conducted carefully lest the seeds be damaged during the removal of the shell. The moisture of the unshelled peanuts is controlled to avoid excessive frangibility of the shells and kernels, which in turn, reduces the amount of dust present in the plant. After, the peanuts are sent to a series of rollers set specifically for the batch of peanuts, where they are cracked. After cracking, the peanuts go through a screening process where they are inspected for contaminants.

Roasting
The dry roasting process employs either the batch or continuous method. In the batch method, peanuts are heated in large quantities in a revolving oven at about 800 °F (427 °C). Next, the peanuts in each batch are uniformly held and roasted in the oven at 320 °F (160 °C) for about 40 to 60 minutes. This method is good to use when the peanuts differ in moisture content. In the continuous method, a hot air roaster is employed. The peanuts pass through the roaster whilst being rocked to permit even roasting. A photometer indicates the completion of dry roasting. This method is favored by large manufacturers since it can lower the rate of spoilage and requires less labor.

Cooling
After dry roasting, peanuts are removed from the oven as quickly as possible and directly placed in a blower-cooler cylinder. There are suction fans in the metal cylinder that can pull a large volume of air through, so the peanuts can be cooled more efficiently. The peanuts will not be dried out because cooling can help retain some oil and moisture. The cooling process is completed when the temperature in the cylinder reaches 86 °F (30 °C).

Blanching
After the kernels have been cooled down, the peanuts will undergo either heat blanching or water blanching to remove the remaining seed coats. Compared to heat blanching, water blanching is a new process. Water blanching first appeared in 1949.

Heat blanching
Peanuts are heated by hot air at 280 °F (138 °C) for not more than 20 minutes in order to soften and split the skins. After that, the peanuts are exposed to continuous steam in a blanching machine. The skins are then removed using either bristles or soft rubber belts. After that, these skins are separated and blown into waste bags. Meanwhile, the hearts of peanuts are segregated through inspection.

Water blanching
After the kernels are arranged in troughs, the skin of the kernel is cracked on opposite sides by rolling it through sharp stationary blades. While the skins are removed, the kernels are brought through a one-minute hot water bath and placed on a swinging pad with canvas on top. The swinging action of the pad rubs off the skins. Afterward, the blanched kernels are dried for at least six hours by hot air at 120 °F (49 °C).

After blanching, the peanuts are screened and inspected to eliminate the burnt and rotten peanuts. A blower is also used to remove light peanuts and discolored peanuts are removed using a color sorting machine.

Grinding
After blanching the peanuts are sent to grinding to be manufactured into peanut butter. The peanuts are then sent through two sizes of grinders. The first grinder produces a medium grind, and the second produces a fine grind. At this point, salt, sugar and a vegetable oil stabilizer are added to the fine grind to produce the peanut butter. This adds flavor and allows the peanut butter to stay as a homogenous mixture. Chopped peanuts may also be added at this stage to produce “chunky” peanut butter.

Packaging

A jar of commercial “creamy” peanut butter

Before packaging, the peanut butter must first be cooled in order to be sealed in jars. The mixture is pumped into a heat exchanger in order to cool it to about 120 °F (49 °C). Once cool, the peanut butter is pumped into jars and vacuum sealed. This vacuum sealing rids the container of oxygen so that oxidation cannot occur, preserving the food. The jars are then labelled and set aside until crystallization occurs. The peanut butter is then packaged into cartons distributed to retailers, where they are stored at room temperature and sold to consumers.

A 2012 article stated that “China and India are the first and second largest producers, respectively”, of peanuts. The United States of America “…is the third largest producer of peanuts (Georgia and Texas are the two major peanut-producing states)” and “more than half of the American peanut crop goes into making peanut butter.”

Nutritional profile
In a 100 gram amount, smooth peanut butter supplies 588 Calories and is composed of 50% fat, 25% protein, 20% carbohydrates (including 6% dietary fiber), and 2% water (table).

Peanut butter is a rich source (20% or more of the Daily Value, DV) of dietary fiber, vitamin E, pantothenic acid, niacin, and vitamin B6 (table, USDA National Nutrient Database). Also high in content are the dietary minerals manganese, magnesium, phosphorus, zinc, and copper (table). Peanut butter is a moderate source (10–19% DV) of thiamin, iron, and potassium (table).

Both crunchy/chunky and smooth peanut butter are sources of saturated (primarily palmitic acid, 21% of total fat) and monounsaturated fats, mainly oleic acid as 47% of total fat, and polyunsaturated fat (28% of total fat), primarily as linoleic acid).

Peanut allergy
For people with a peanut allergy, peanut butter can cause a variety of possible allergic reactions, including life-threatening anaphylaxis. This potential effect has led to banning peanut butter, among other common foods, in some schools.

Symptoms
* Shortness of breath
* Wheezing
* Tightening of the throat
* Itching
* Skin reactions such as hives and swelling
* Digestive problems

Peanut butter cookies, a popular type of cookie made from peanut butter and other ingredients

As an ingredient
Peanut butter is included as an ingredient in many recipes: peanut butter and jelly sandwiches, peanut butter cookies, and candies where peanut is the main flavor, such as Reese’s Pieces, or various peanut butter and chocolate treats, such as Reese’s Peanut Butter Cups and the Crispy Crunch candy bar.

Peanut butter’s flavor combines well with other flavors, such as oatmeal, cheese, cured meats, savory sauces, and various types of breads and crackers. The creamy or crunchy, fatty, salty taste pairs very well with complementary soft and sweet ingredients like fruit preserves, bananas, apples, and honey. The taste can also be enhanced by similarly salty things like bacon (see peanut butter, banana and bacon sandwich), especially if the peanut butter has added sweetness.

One snack for children is called “Ants on a Log”, with a celery stick acting as the “log”. The groove in the celery stick is filled with peanut butter and raisins arranged in a row along the top are “ants”.

Plumpy’nut is a peanut butter-based food used to fight malnutrition in famine-stricken countries. A single pack contains 500 calories, can be stored unrefrigerated for 2 years, and requires no cooking or preparation.

As animal food
Peanut butter inside a hollow chew toy is a method to occupy a dog with a favored treat. A common outdoor bird feeder is a coating of peanut butter on a pine cone with an overlying layer of birdseed.