Pistachio nuts are dry fruits of species of trees belonging in the Anacardiaceae family, in the genus: Pistacia. The plant is a medium sized broad, bushy, dioecious, deciduous tree, believed to be originating in the mountain ranges of West-Asian region. Several cultivars exist; however, the most popular variety grown for the commercial purpose is the kerman.
Pistachios grow well under hot, dry climates with cool winters. They are currently being cultivated in large scale in the orchards in the USA, Iran, Syria, Turkey, and China. After plantation, it takes approximately eight to ten years until it produces its first major crop. Once established, it keeps bearing fruits for centuries.
The fruit, in fact, is a drupe (fruit with a large, central located single seed), and its seed kernel is actually the edible portion. Each season, the tree bears heavy clusters of fruits, which appear somewhat like that of a grape bunch. On the exterior, the mature fruit features hard, off-white color shell which splits apart exposing yellow-light green, oblong shape kernel inside. Pistachio kernel measures about 1 inch in length and 1/2 inch in diameter and weighs about 0.7-1 gm.
Additionally, remains of the Atlantic pistachio and pistachio seed along with nut-cracking tools were discovered by archaeologists at the Gesher Benot Ya'aqov site in Israel's Hula Valley, dated to 78,000 years ago. Healthy Food - Pistachio.
Pliny the Elder in his Natural History asserts that pistacia, “well known among us,” was one of the trees unique to Syria, and that the seed was introduced into Italy by the Roman consul in Syria, Lucius Vitellius the Elder (consul in Syria in 35 AD) and into Hispania at the same time by Flaccus Pompeius. The early sixth-century manuscript De observatione ciborum (“On the observance of foods”) by Anthimus implies that pistacia remained well known in Europe in Late Antiquity. The pistachio is one of three seeds mentioned in the Bible. The pistachio is mentioned once, in Genesis 43:11, as is the walnut in Song of Songs 6:11, while the almond is mentioned many times.
More recently, the pistachio has been cultivated commercially in many parts of the English-speaking world, in Australia, and in New Mexico and California, of the United States, where it was introduced in 1854 as a garden tree. David Fairchild of the United States Department of Agriculture introduced hardier cultivars collected in China to California in 1904 and 1905, but it was not promoted as a commercial crop until 1929. Walter T. Swingle’s pistachios from Syria had already fruited well at Niles by 1917.
The earliest records of pistachio in English are around roughly year 1400, with the spellings “pistace” and “pistacia”. The word pistachio comes from medieval Italian pistacchio, which is from classical Latin pistacium, which is from ancient Greek pistákion and pistákē, which is generally believed to be from Middle Persian, although unattested in Middle Persian. Later in Persian, the word is attested in Persian as pista. As mentioned, the tree came to the ancient Greeks from Western Asia.
Pistachio is a desert plant, and is highly tolerant of saline soil. It has been reported to grow well when irrigated with water having 3,000–4,000 ppm of soluble salts. Pistachio trees are fairly hardy in the right conditions, and can survive temperatures ranging between −10 °C (14 °F) in winter and 48 °C (118 °F) in summer. They need a sunny position and well-drained soil. Pistachio trees do poorly in conditions of high humidity, and are susceptible to root rot in winter if they get too much water and the soil is not sufficiently free-draining. Long, hot summers are required for proper ripening of the fruit.
The Jylgyndy Forest Reserve, a preserve protecting the native habitat of Pistacia vera groves, is located in the Nooken District of Jalal-Abad Province of Kyrgyzstan.
The fruit is a drupe, containing an elongated seed, which is the edible portion. The seed, commonly thought of as a nut, is a culinary nut, not a botanical nut. The fruit has a hard, creamish exterior shell. The seed has a mauvish skin and light green flesh, with a distinctive flavor. When the fruit ripens, the shell changes from green to an autumnal yellow/red, and abruptly splits part way open (see photo). This is known as dehiscence, and happens with an audible pop. The splitting open is a trait that has been selected by humans. Commercial cultivars vary in how consistently they split open.
Each pistachio tree averages around 50 kilograms (110 lb) of seeds, or around 50,000, every two years. Healthy Food - Pistachio.
The shell of the pistachio is naturally a beige color, but it is sometimes dyed red or green in commercial pistachios. Originally, dye was applied by importers to hide stains on the shells caused when the seeds were picked by hand. Most pistachios are now picked by machine and the shells remain unstained, making dyeing unnecessary except to meet ingrained consumer expectations. Roasted pistachio seeds can be artificially turned red if they are marinated prior to roasting in a salt and strawberry marinade, or salt and citrus salts.
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.
Health benefits of Pistachios
- Pistachios are an excellent sources of vitamin-E, especially rich in gamma-tocopherol; contain about 23 g per100 g. vitamin E is a powerful lipid soluble antioxidant, essential for maintaining the integrity of cell membrane of mucus membranes and skin; offer protection from harmful oxygen-free radicals.
- Pistachios are delicious tree nuts recognized for their wholesome nutrition properties. Together with walnuts, almonds, and cashew, they form important source of protein, fats, and minerals to otherwise dry and arid regions of Central, West and South Asian population.
- Pistachios are rich source of energy; 100 g of nuts provides 557 calories. In addition, they are rich in mono-unsaturated fatty acids like oleic acid and an excellent source of antioxidants. Regular consumption of pistachios in the diet helps to lower total as well as bad LDL cholesterol and increases good HDL cholesterol levels within the blood. Research studies suggest that Mediterranean diet that is rich in dietary-fiber, mono-unsaturated fatty acids, and antioxidants help to prevent coronary artery disease and strokes by favoring healthy blood lipid profile.
- Pistachio oil extracted from these nuts is one of the healthiest cooking oils. It has pleasent nutty aroma and has excellent emollient properties. It helps keep skin well protected from dryness. Besides been used in cooking, it also employed as “carrier or base oil” in traditional medicines in massage therapy, aromatherapy, in pharmaceutical, and cosmetic industry.
- The nuts are packed with many important B-complex groups of vitamins such as riboflavin, niacin, thiamin, pantothenic acid, vitamin B-6, and folates.
- They are rich source of many phyto-chemical substances that may contribute to their overall antioxidant activity, including carotenes, vitamin E, and polyphenolic antioxidant compounds. Research studies have been suggestive of that these compounds help remove toxic oxygen-free radicals from the body, and thus, protect it from diseases, cancers, as well as infections.
- They are the storehouse of minerals like copper, manganese, potassium, calcium, iron, magnesium, zinc, and selenium. 100 g nuts provide 144% of daily-recommended levels of copper. Copper is an essential trace mineral that is required in neuro-transmission, metabolism, as well as red blood cell (RBC) synthesis.
Just a hand full of pistachios a day provides enough recommended levels of phenolic anti-oxidants, minerals, vitamins, and protein. Healthy Food - Pistachio.
Selection and storage
Pistachios are available in the markets year around. In the grocery stores, one may choose shelled, unshelled (with-shell), roasted, salted, sweetened, etc forms of nuts displayed for sale. Try to buy completely unshelled (with intact outer coat) nuts instead of processed ones. They are generally available in the airtight packs as well as in bulk bins.
Look for healthy, compact, uniform, off white color whole shell nuts that feel heavy in hand. They should be free from cracks other than the natural split, mold, spots, and of rancid smell.
Raw, unshelled pistachios can be placed in a cool dry place for couple of months. However, shelled kernels should be placed inside an airtight container and kept inside the refrigerator in order to prevent them turn rancid.
- Pistachios are nutty, yet pleasantly sweet in taste with a fruity aroma. Baklava, a sweet-pastry made of layers of paper-thin "phyllo or strudel dough" filled with chopped pistachio, almonds and cashew nuts and sweetened with syrup or honey, is a popular pastry preparation in Turkey, Iran, Armenia, and many Middle East states.
- Popularly known as "pista," these nuts have been widely used in sweet dishes in Indian, Pakistani and other South-East Asian countries.
- Roasted and crushed nuts often sprinkled over salads, desserts, particularly sundaes and other ice cream based dessert preparations (for example, kulfi in Indian subcontinent), biscuits, sweets and cakes.
- Split pistachios are a great addition to vegetable/fruit salads.
- The nuts are usually eaten as thay are, by cracking them open between fingers or using a nutcracker machine. They can also be enjoyed roasted, salted, or sweetened, just as in macadamia and peanuts.
Pistachio nut allergy sometimes occur as an allergic manifestations due to chemical compound anacardic acid (urushiol) that is present in these nuts. Cross-reactions may also occur with some other related nuts and fruits of Anacardiaceae family such as mango, cashew nuts... etc. Persons with known allergic reactions to these nuts may, therefore, require to observe caution while eating cashews and mango, and conversely.
The reaction symptoms may range from simple skin itching (hives) to severe form anaphylactic manifestations, including breathing difficulty, pain abdomen, vomiting, and diarrhea. Healthy Food - Pistachio.
Recycling the shells