Pistachio
Resources > Food > Culinary Nuts > Pistachio

Are you a Smart Kitchen™ Chef?

Try it FREE or take a TOUR to explore Smart Kitchen!
+ -

 

What we call a Pistachio Nut is actually the drupe fruit of the Pistachio Tree, and not a biological Nut at all. The drupe fruit has a whitish exterior shell and contains an elongated Seed. Because the differences only really matter to a biologist and because we use Pistachios in the kitchen as though they are a Nut, we group them in a category called Culinary Nuts.

Though Iran is often cited as the source of the original wild Pistachio trees, remains of the Atlantic Pistachio, its seeds and nut cracking tools dating to 760,000 years ago have been found in Israel’s Hula Valley. The Atlantic Pistachio is a cousin to our modern commercial Pistachio Tree (Pistacia vera in the Anacardiaceae family which includes Poison Ivy, Mangoes and Cashews) and the two, as well as most species in the genus Pistachio, are easily confused.

According to the archeological record, man has been enjoying the Pistachio vera since at least 6750 BC, where evidence of Pistachios as a food have been found. Pistachios were reported to have been planted in the famous Hanging Gardens of Babylon and they are one of the only two “nuts” mentioned in the Bible (Genesis 43:11). Almonds are the other. Pliny the Elder, the Roman author, mentions Pistachios in his “Natural History” and asserts that the Roman Consul in Syria introduced Pistachios to Italy around 35 A.D.

The Pistachio is not mentioned in English until 1,400 A.D. at the earliest, and it was not until 1854 that Pistachios were imported to the United States, primarily as a garden tree. It took until 1929 for Pistachios to be exploited as a commercial crop.

Cultivation

The Pistachio is a desert plant and is very tolerant of saline soil. Pistachios need long hot summers to ripen properly. Pistachio trees do poorly with high humidity and can get root rot if they get too much water.

When the Pistachio’s drupe fruit ripens (the part we consider the nut), the shell changes from green to a whitish/yellow/beige, which is the natural shell color. You may find red or green shelled Pistachios but they are usually imports dyed to hide any stains resulting from manual harvesting of the Pistachios. Most domestic Pistachios are machine harvested, so staining is less of a problem in the U.S.

As the Pistachio ripens, the shell will suddenly split apart with an audible “Pop,” in a process known as “dehiscence,” which is a desirable trait that farmers have bred into almost all commercial Pistachio Cultivars.

Production

Turkey, the United States (specifically California) and Iran are the major producers of Pistachios. Farmers plant the Pistachio Trees in orchards at a density of 120 trees per acre. The Pistachio trees take 7 to 10 years to become productive, with peak productivity taking 20 years to achieve. Pistachio Trees bear biennially, meaning that alternate years have a heavier crop. Each tree will yield 80 pounds to 110 pounds (36 kg to 50 kg) of fruit a year on average once they are mature.

Trees are usually pruned to size to make the harvest easier. One male tree produces enough pollen for eight to twelve nut-bearing females. Harvesting in the United States and in Greece is often accomplished by using shaking equipment to shake the nuts off the tree. After hulling and drying, pistachios are sorted according to open mouth and closed mouth shell. Sun drying has been found to be the best method of drying. Then they are roasted or processed by special machines to produce pistachio kernels.

Pistachio trees are vulnerable to a wide variety of diseases (see list of pistachio diseases). Among these is infection by the fungus Botryosphaeria, which causes panicle and shoot blight (i.e., kills flowers and young shoots), and can damage entire pistachio orchards.

In California, almost all female pistachio trees are the cultivar "Kerman". A scion from a mature female Kerman is grafted onto a one-year-old rootstock. Male pistachios may be a different variety.  California grows 98% of all U.S. Pistachios. Each individual Pistachio requires about 0.75 gallons of water to reach maturity. 

In Greece, the cultivated type of pistachios is different. It has an almost-white shell, a sweet taste, a red-green kernel and a little bit more close mouth shell than "Kerman" variety. Most of the production in Greece comes from the island of Aegina and the region of Thessaly.

Purchasing

You may find red or green shelled Pistachios but they are usually imports dyed to hide any stains resulting from manual harvesting of the Pistachios. Most domestic Pistachios are machine harvested, so staining is less of a problem in the U.S.

Most pistachios are now picked by machine and the shells remain unstained, making dyeing unnecessary except to meet ingrained consumer expectations. Roasted pistachio nuts can be artificially turned red if they are marinated prior to roasting in a salt and strawberry marinade, or salt and citrus salts.

Bulk container shipments of pistachio kernels are prone to self-heating and spontaneous combustion because of their high fat and low water content.

Storage

Store in a cool/dry place.

Culinary Uses

There is even a use for all of those empty Pistachio shells, if you buy the Pistachios in bulk and shell them yourself. Empty Pistachio shells make great kindling for starting a fire in the fireplace or in the Grill. They also make a good mulch for plants that thrive in acidic soils.

Nutritional Value USDA
PISTACHIO NUTS,RAW
Amount Per 100g
Calories 562
%Daily Value*
 
69%
Total Fat 45g
3%
Saturated Fat 5g
Polyunsaturated Fat 13g
Monounsaturated Fat 23g
0%
Cholesterol 0mg
0%
Sodium 1mg
21%
Potassium 1025mg
9%
Total Carbohydrate 27g
40%
Dietary Fiber 10g
Sugars 7g
Protein 20g
* Percent Daily Values are based on a 2,000 calorie diet. Your Daily Values may be higher or lower depending on your calorie needs.
Nutrition

A serving of Pistachios is 1/4 Cup (50 ml) or a small handful of about 40 to 49 nuts which will weigh about 1 to 1.3 oz (31 to 38 grams).

In the world of Culinary Nuts, a serving of Pistachios (1/4 cup (50 ml) about 40-49 kernels (31 grams) or a small handful) has the least calories per ounce, are a Monounsaturated Fat (90%), and are a good source of the Antioxidants, LuteinAlpha-Carotene,  Beta-Carotene and Vitamin E. They also contain a good amount of Vitamin B6PotassiumPhosphorusCopperManganeseMagnesium and Dietary Fiber (12% as much as a bowl of Oatmeal).

Since July 2003, Pistachios have been considered a heart healthy food. In 2003 the Food and Drug Administration (FDA) approved the first qualified health claim specific to nuts lowering the risk of heart disease: "Scientific evidence suggests but does not prove that eating 1.5 ounces (42.5g) per day of most nuts, such as pistachios, as part of a diet low in saturated fat and cholesterol may reduce the risk of heart disease."

The FDA approved the claim because numerous studies have shown that Pistachios help lower LDL (the bad cholesterol) and animal studies indicate that Pistachios can help raise HDL (good cholesterol). In some studies LDL was lowered up to 11%. It is thought that the Phytosterols in Pistachios are what make them so effective against cholesterol.

Salted & Roasted Pistachios can be fairly salty (126 mg of sodium per serving). If you are watching your sodium intake, you may want to switch to roasted but un-salted Pistachios which have only 3 mg of sodium per serving.

The USDA also places Pistachios among the top Antioxidant foods. Human studies have shown that 32–63 grams per day of Pistachios can significantly elevate plasma levels of LuteinAlpha-CaroteneBeta-Carotene, and Gamma-Tocopherol.

Allergens

Like other members of the Anacardiaceae family (which includes poison ivy, sumac, mango, and cashew), pistachios contain urushiol, an irritant that can cause allergic reactions.

Gluten Free

Yes

Low Fat

No

Low Calorie

No