Pumpkin seed oil

Styrian pumpkin seed oil is traditionally made from the roasted seeds of Styrian oil pumpkins (Cucurbita pepo var. styriaca). However, pumpkin seed oil can also be made from raw seeds. Pumpkin seed oil is sometimes referred to as “green gold.” Its nutty taste adds a nice flavor to a wide range of dishes.

Culinary uses:

Pumpkin seed oil is an excellent dressing for raw vegetables and all kinds of salads. As a nutty, flavorsome oil, it is used to season dishes such as soups, casseroles, risotto, and pasta. Pumpkin seed oil has a slightly sweet taste, making it suitable for special desserts such as ice creams, parfaits, puddings, and cakes. It is furthermore excellent in creamy spreads and dips, making it ideal for aperitifs and snacks.

Although the seeds are usually roasted prior to oil production, pumpkin seed oil is a heat-sensitive oil, both when made from roasted and unroasted pumpkin seeds. When heated above 100 °C, pumpkin seed oil loses its greenish color, flavorsome taste, and some of its healthy nutrients. It may also develop unhealthy bittering agents. Pumpkin seed oil should therefore not be used for cooking, frying, or deep-frying.

Vegan recipe for Pumpkin Seed Pesto with Pumpkin Seed Oil:

This pumpkin seed pesto is quick and easy to prepare, and can be made a few days before serving.

Purchasing — where to shop?

One of the most well-known and high quality pumpkin seed oils comes from Styria, a state in southern Austria. Styrian pumpkin seed oil is often referred to as the “original” pumpkin seed oil because the Styrian oil pumpkin (Cucurbita pepo var. styriaca) comes from this region. Oil from pumpkins is also extracted in other regions and countries, but its quality is often inferior. Styrian pumpkin seed oil is geographically protected and has PGI status (protected geographical indication).

Traditional Styrian pumpkin seed oil is made from roasted pumpkin seeds; the oil itself is no longer heated. A more intense roasting may affect the taste and color of the oil. Pure Styrian pumpkin seed oil can be recognized by checking the label for the place of production (Austria) and words such as genuine and 100%.¹ Good pumpkin seed oil has a rather viscous consistency, smells pleasantly nutty, and tastes sweetish and flavorsome. Depending on the degree of roasting, the color ranges from dark green to reddish brown.

You can often find pumpkin seed oil at supermarkets such as Walmart, Whole Foods Markets, Kroger, and Safeway (United States); Asda, Sainsbury’s, Tesco, Aldi, Lidl, and Holland & Barret (Great Britain); Metro, Extra Foods, and Goodness Me (Canada); and Coles, Woolworths, and Harris Farm (Australia). If you are looking for real Styrian pumpkin seed oil, it is best to shop online. Pumpkin seed oil is sometimes found in blends with other edible oils, which are referred to as salad oil, edible oil, or table oil. However, some products sold as “genuine pumpkin seed oil” may be misleading, often containing stretched pumpkin seed oil. While these blends are almost indistinguishable from real pumpkin seed oil, the consistency of the stretched variant is somewhat thinner, the color is less intense and it may have a “greasy” taste.¹ An Austrian product-testing magazine (Der Konsument) found that stretched pumpkin seed oil produced outside Austria and from discount brands contained pesticide residues. These residues included the insecticide DDT, which is banned in Europe and the US.²

If possible, buy organic pumpkin seed oil. If you order on the Internet, be sure to check that you have found a trustworthy supplier, or order directly from the producer.

Organic pumpkin seed oil made from unroasted pumpkin seeds is also available, mostly on the Internet. Note that unroasted pumpkin seed oil cannot be called “Styrian pumpkin seed oil,” even if it comes from this region.³ Unroasted oil is a yellowish-green color, meaning it is significantly lighter than roasted pumpkin seed oil, which is greenish-brown.

Storing:

How long can you store pumpkin seed oil for? If stored in a cool (below 20° C) and dark place, the oil can be kept for a good 12 months in a closed bottle. Used bottles are best kept in the refrigerator. Once open, a bottle of pumpkin seed oil should be used up within 2–3 months, as the oil begins to oxidize and loses not only its vitamins, but also its flavor. You should definitely throw out rancid smelling pumpkin seed oil. It’s best to store pumpkin seed oil in dark glass bottles. This protects the oil a little better from the effects of light.

Production:

Pumpkin seed oil is usually pressed from the seeds of the Styrian oil pumpkin (Cucurbita pepo var. styriaca). One oil pumpkin produces about 1000 pumpkin seeds. Traditionally, the seeds are washed and dried and then ground into pumpkin seed flour. In order to obtain the oil from the dry flour, the ground seeds are mixed with water and salt. This separates the protein from the fat. Roasting the seeds slowly allows the water to evaporate. The oil cake is then pressed mechanically or hydraulically to obtain the pumpkin seed oil. This process is neither a cold pressing nor a hot pressing. The oil is not actively heated during the pressing process, but the ground raw material is roasted at a maximum temperature of 120 °C before pressing. The smoke point of pumpkin seed oil is also at this temperature, above which trans fats form.¹ As a comparison, sunflower and flaxseed oil have a smoke point of approximately 107 °C, cold-pressed canola oil 130 °C, and refined canola oil 200 °C.

Industrial pumpkin seed oil is produced by pressing warm chopped and roasted seeds of the garden pumpkin under high pressure with a hydraulic press. It is difficult to verify the temperatures that are reached in industrial production.

The Codex Alimentarius Austriacus (Das österreichische Lebensmittelbuch) defines cold-pressed oils as follows: “Cold-pressed oils are unrefined oils that are obtained by mechanical processes without heat input. They are not degummed, (partially) neutralized, bleached, deodorized, or fractionated. Decanting, filtering, and centrifuging are common methods for removing turbidity. Filtration is carried out with paper, stock filters, or other filter aids. It is possible that cold-pressed oils have undergone pretreatment and posttreatment processes such as roasting and washing the raw seeds, and steaming the oil — these processes are indicated on the product.”⁴

In the Codex Alimentarius Austriacus, you can also find the definition of pumpkin seed oil production: “Pumpkin seeds, the seeds of the common field pumpkin Curcurbita pepo and other pumpkin varieties, produce a yellowish-green oil when peeled and pressed. If, however, these seeds are roasted before pressing, a yellowish-brown to dark greenish-brown oil is produced. Pumpkin seed oil produced in Austria (primarily in Styria) is predominantly obtained for the shelled seeds of the Styrian oil pumpkin (Curcurbita pepo styriaca). These seeds are always roasted before pressing. Pressing results in a dark-colored, dichroic oil that appears greenish-brown in transmitted light. Only pumpkin seeds that have been selected and carefully treated are pressed.”⁴

Nutrients — nutritional information — calories:

Pumpkin seed oil has a high content of polyunsaturated fatty acids. In addition to alpha- and beta-tocopherol (vitamin E), which has antioxidant effects, pumpkin seed oil also contains selenium and the carotenoids lutein and zeaxanthin. Vitamin K and other phytonutrients such as phytosterols, beta-sitosterol, and delta-7 sterols are also present.^5,6.

Pumpkin seed oil’s green to red fluorescent color comes from the shell pigments in the oil: chlorophyll a and b and pheophytin (chlorophyll molecule without central Mg-ion).^7,8.

Does pumpkin seed oil contain omega-3? At 0.48 g per 100 g, pumpkin seed oil contains relatively low levels of omega-3 fatty acids. The ratio between inflammatory omega-6 fatty acids (LA) and anti-inflammatory omega-3 fatty acids (ALA) is alarmingly high in pumpkin seed oil (102:1), particularly given the fact that the Western diet already contains very high quantities of omega-6 fatty acids. For pumpkin seeds, this ratio may be as high as 172:1. According to the Swiss Federal Office of Public Health (FOPH), a healthy ratio of omega-6 to omega-3 fatty acids should not exceed 5:1. This disease-promoting aspect of pumpkin seed oil is of course not found in advertising; studies are also almost exclusively undertaken in contexts where the aim is to promote the sale of the oil.

Eating Erb Muesli is an example of how you can improve your fatty acid ratio in favor of omega-3 fatty acids. In the list of ingredients, use the “sort by nutritional values” function to select healthy ingredients or ingredients that may balance out your meals. This function can also be used in recipes, allowing you, for example, to sort ingredients by their omega-6 to omega-3 ratio.

Health aspects — effects:

What is pumpkin seed oil good for? The oil’s high content of polyunsaturated fatty acids has vasodilatory effects and can lower blood pressure, thus helping to prevent cardiovascular problems. The high proportion of phytosterols is said to have a cholesterol-lowering effect.

Dangers — intolerances — side effects:

At 102:1, pumpkin seeds and pumpkin seed oil unfortunately have an extremely poor ratio between linoleic acid (LA, inflammatory) and alpha-linolenic acid (ALA, anti-inflammatory).⁵ See the ingredient tables below and the link in the box above. To compensate for this imbalance and improve your LA:ALA ratio, you should add ingredients like flaxseed, Brazil nuts, and macadamia nuts to your dishes.

Use as a medicinal plant:

In naturopathy, it has long been known that pumpkin seeds have a positive effect on prostate health. Today, mainstream medicine is also aware of these benefits and there are now prostate medications that get their active ingredients from pumpkin seeds. To date, studies have shown a positive effect of pumpkin seeds on the urinary tract, bladder, and especially on the prostate.^9,10

For a long time, research assumed that it was the fat-soluble substances contained in pumpkin seed oil that had a positive effect on the bladder and prostate. Recent research has shown that water-soluble lignans (phytonutrients similar to estrogens) have a regulating effect on bladder function. However, high concentrations of lignans are found in aqueous extracts of pumpkin seeds but are hardly contained in pumpkin seed oil. According to the latest scientific studies, it appears that pumpkin seed oil’s effectiveness in treating an enlarged prostate and stress-induced incontinence is limited because it contains low levels of lignans. Studies conducted by the Taiwanese National Cheng Kung University in 2006 demonstrated pumpkin seed oil’s curative power in treating an enlarged prostate, but these experiments were conducted on animals.¹¹

High quality pumpkin seed oil is considered to have the highest amount of antioxidants of all edible oils. It therefore not only prevents cancer, but can also help with many heart, circulation, and lung diseases. The University of Graz conducted an interesting study where the health effects of pumpkin seed oil were investigated in relation to the fight against free radicals. According to this study, pumpkin seed oil is supposed to be an effective opponent of free radicals, preventing the development of arteriosclerosis.¹²

A study by the University of the West Indies in Kingston, Jamaica, investigated the potential benefits of pumpkin seed oil for conditions specific to women. Researchers observed a blood pressure-lowering effect of pumpkin seed oil in postmenopausal women. Furthermore, an increase in “good” HDL cholesterol levels was also observed, which is important for keeping your cholesterol metabolism in balance. However, this experiment of consuming 2 g pumpkin seed oil per day only lasted 12 days.¹³

According to a recent study in 2014, pumpkin seed oil could be an effective remedy for genetic hair loss. Seventy-six Korean participants were given 400 mg pumpkin seed oil daily for half a year. Their hair density increased by up to 40 %. The researchers suspect that this is because pumpkin seed oil contains less DHT than typical male hormone levels. The beta-sitosterol contained in pumpkin seed oil inhibits an enzyme that converts the male hormone “T” (17β-Hydroxyandrost-4-en-3-one) into DHT.¹⁴

Pumpkin seed oil is also said to help get rid of intestinal parasites.¹⁵

Pumpkin seed oil has many health-promoting properties. It would nevertheless be exaggerated to describe the oil as a superfood, especially because of its high ratio of polyunsaturated fatty acids.

Occurrence — origin:

The original domesticated pumpkin, Cucurbita pepo, dates back to the inhabitants of the caves of Guilá Naquitz in the province of Oaxaca (not Oxaca), Mexico, about 10'000 years ago. There is also evidence of its occurrence in Tikal (2000 BCE to 850 CE) and Peru (3000 BCE). The Cucurbita moschata (including butternut squash and giromon) was domesticated in Central America, while the Cucurbita maxima (including buttercup squash) was first cultivated in South America. There is also evidence that pumpkin was cultivated in India, Java, Angola, and Japan from the nineteenth century onwards.

The history of pumpkin seed oil dates back to 1735, when it was made from thick seeds. Today, pumpkin seed oil is made using pumpkin seeds that have a very thin shell, a variety of pumpkin that began to grow between 1870 and 1880 in Styria. Until the 1970s, pumpkin seed oil was only known within Austria in southern Styria. It was not until the 1980s that it expanded into kitchens around the world.

Today, the Styrian oil pumpkin is cultivated in southern Styria, in southern Burgenland (as well as the bordering regions of Hungary and Slovenia), and in Russia.

Pumpkins are generally cultivated in climates that range from hot, dry regions to cool cloud forests. However, most species grow in hot lowland climates with distinct wet and dry seasons. Pumpkins need lots of sunlight and are sensitive to frost.

Cultivation — harvest:

Information on pumpkin cultivation and the pumpkin season can be found on the page about pumpkin (squash).

Animal protection — species protection — animal welfare:

According to Wikipedia, flowers of the Cucurbita genus are important for insects that collect pollen and nectar, particularly bees of the Peponapis pruinosa and Xenoglossa genera. These flowers bloom during the day.¹⁷

General information:

The Styrian oil pumpkin (Cucurbita pepo var. styriaca) originates from the garden pumpkin (Cucurbita pepo) and belongs to the pumpkin family (Cucurbitaceae). The Styrian oil pumpkin is used almost exclusively to produce pumpkin seed oil. The Styrian oil pumpkin underwent a mutation over 100 years ago that resulted in seeds that now no longer have a thick shell. Cucurbita pepo var. styriaca’s seeds have a very thin outer layer. This makes it easier to obtain pumpkin seed oil in large quantities.¹⁶

Further information on pumpkin can be found on the pages for the following ingredients: hokkaido pumpkin, butternut pumpkin, summer squash, and pumpkin (squash).

Alternative names:

Pumpkin seed oil is called Kürbiskernöl, Kernöl, Kürbisöl, and Steirisches Kürbiskernöl in German.

Keywords for use:

The oil cake (press cake) of the pumpkin seeds can be used as a high quality, protein-rich feed for cattle and pigs.¹⁶

Cosmetic uses:

Is pumpkin seed oil good for your skin? In cosmetics, pumpkin seed oil is often used as a base oil because it contains many active ingredients that are good for skin care, such as vitamin E and carotenoids. Pumpkin seed oil is said to help with dehydrated skin, wrinkling, skin aging, stretch marks, and flaky and cracked skin.

Literature — sources:

Author: Kerstin Gackle | 29 Sept 2017