Hemp oil

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Hemp oil
Raw material plant (noun)

Industrial hemp ( Cannabis sativa )

origin

Seeds

colour

green-yellowish (cold-pressed), dark green (hot-pressed)

ingredients
Oleic acid 10-15%
Linoleic acid 50-60%
Linolenic acid up to 29% ( α-linolenic acid up to 25%, γ-linolenic acid up to 4%)
Palmitic acid 7%
More fatty acids Gadoleic acid <1%, stearic acid 1–3%, stearidonic acid 0.5–1.5%, arachidic acid 0–2%
Σ saturated fat 8-13%
Σ monounsaturated fatty acids 12-17%
Σ polyunsaturated fatty acids 70-80%
Vitamin E 2 up to 80 mg / 100 g
Other ingredients Tocopherol 468-950 mg / kg, tetrahydrocannabinol 50 mg / kg
properties
density 0.924-0.932 kg / l at 15 ° C
viscosity = 50-70 mm 2 · s −1 at 20 ° C; 27.4-29.3 mm 2 s −1 at 40 ° C
Oxidation stability 1.3-2.5 h
Melting point −25 ° C ... −15 ° C
Smoke point 165 ° C
Flash point 250-265 ° C; 308 ° C
Iodine number 149-167
Saponification number 190-194
Calorific value 39.5 MJ / kg
Cetane number 39.5-48.7
Manufacturing and Consumption
Most important production countries France , China, Chile
Consumption worldwide 1254 t (2003)

Hemp oil is a fatty vegetable oil that is obtained from the seeds of industrial hemp ( Cannabis sativa ).

It is often confused with other oily hemp products from which it needs to be distinguished. Hemp oil is an edible oil and must therefore not be confused with essential hemp oil (obtained from distilled leaves and flowers) or hashish oil (oily resin extract with a high content of THC).

Unlike the resin of the plant, hemp seeds do not contain any significant amounts of tetrahydrocannabinol (THC). Therefore, they do not have an intoxicating psychoactive effect , which accordingly also applies to the oil produced from them.

Manufacturing

Since the industrial cultivation of hemp is usually done for the production of hemp fibers, the seeds and thus also the hemp oil are only a by-product of the cultivation. The seeds are obtained and processed during the preparation of the harvested hemp plants . If you want to extract high-quality hemp oil from the hemp seeds, careful harvesting and oil extraction are essential.

Due to its firm shell, the seed is protected from environmental influences such as oxygen and sunlight. If you want to extract oil from the seeds, you have to carefully peel them, which is usually done by machine. Then the hemp nuts are pressed in an oil mill . Cold pressing is best for this , as the pressing temperature here is between 40 ° C and 60 ° C, and thus the valuable ingredients of the hemp oil are not damaged or reduced by heat. With an oil content of 30 to 35%, the oil yield is around 180 to 350 liters per hectare. The press cake (hemp cake) contains a lot of protein and can be used as feed.

  • Hemp seeds ("hemp nuts") with shells.

  • Hemp seeds (peeled) ready for oil extraction.

properties

General chemical structure of oils, such as hemp oil. R 1 , R 2 and R 3 therein are alkyl radicals (20%) or alkenyl radicals (85%) with a mostly uneven number of carbon atoms.

Hemp oil is one of the fatty oils . Chemically, like other oils, it is a homogeneous mixture of liquid triglycerides . The color differs depending on the production method. Cold-pressed hemp oil is green-yellowish, while warm-pressed hemp oil is dark green. Hemp oil smells herbaceous and aromatic and has a green-nutty odor. The taste varies from nutty to herbaceous.

durability

If the hemp oil is kept airtight, the shelf life is at least 60 weeks; As with other oils, dark and refrigerated storage also reduces the gradual decomposition due to oxidation .

composition

In addition to various other plant substances, such as chlorophylls , carotenoids and vitamins , hemp oil is largely composed of fatty acids (over 70% are unsaturated ). For human nutrition, the polyunsaturated fatty acids contained in the oil are of greater importance, especially linoleic acid and alpha-linolenic acid , the two omega-n fatty acids that are essential for humans, and gamma-linolenic acid , an omega-6 that is rare in edible oils. Fatty acid . Their content in hemp oil is remarkably high at up to 4 g / 100 g. Hemp oil also contains stearidonic acid , an omega-3 fatty acid that is converted by the body into the fatty acid EPA . The omega-6 to omega-3 fatty acid ratio of hemp oil is relatively low at around 2: 1 to 3: 1, which is considered beneficial for health.

In addition, hemp oil also contains various other plant substances that are released by pressing, such. B. Chlorophylls and carotenoids , which are also responsible for its color. It also contains relatively large amounts of tocopherol (approx. 800 mg / 100 g, of which approx. 80% γ-tocopherol) and phytosterols (3.6–6.7 g / kg).

use

The use of hemp as a useful plant can be traced back a long way in history; the earliest ropes made from hemp fibers date from around 2,800 BC. From China and its use as textile fiber is proven by finds from the Zhou dynasty (1122 to 149 BC). The earliest use of hemp oil as food or for other uses, however, cannot be dated today.

By the Single Convention on Narcotic Drugs of 1961, in the course of which has been largely banned the cultivation of hemp in most countries, the use of hemp products fell into oblivion. Since the 1990s in particular, the various possible uses have been gradually rediscovered, established and partially legalized.

In the kitchen

Due to its fatty acid spectrum, which contains all essential fatty acids that are important for humans, hemp oil is considered a nutritionally valuable vegetable oil and is often used in the kitchen. Because of its nutty taste, it is mainly used as an edible oil in the preparation of salads , dressings , sauces , marinades and spreads . Due to its relatively low smoke point of around 165 ° C, however, it should not be used for frying or deep-frying , otherwise the fatty acids would decompose at a higher temperature and the taste of the oil would change. In contrast, the use of hemp oil for stewing and steaming is harmless .

Cosmetics manufacturing

Hemp oil is used in the cosmetics industry in the manufacture of a wide variety of products such as massage oils, ointments, creams, soaps and shampoos .

In the medicine

In medicine, it is used to treat inflammation of the ears, nose and throat, and especially in dermatology for inflammatory skin diseases.

As a technical oil

Hemp oil is also used as a technical oil in industry. Because of its high triacylglycerine content, it is used here as a raw material for the production of cleaning agents. Various chemical processes ( saponification , ethoxylation and sulfation ) can be used to produce various raw materials (including soaps, emulsifiers , solvents , care products or surfactants ) for the cleaning industry from hemp oil , which have the advantage that they are easily biodegradable. Furthermore, because of its high lubricity, hemp oil is used for the production of printing inks, paints and varnishes and is also used in the production of wood preservatives, lubricants and crayons. In the Orient in particular , it is still used today as lamp oil because it burns particularly brightly and, in conjunction with essential hemp oil, develops the smell typical of hemp.

As a biofuel

Hemp oil is still not used to generate energy. Although it could be used as a basis for vegetable oil -based fuels ( biodiesel , vegetable oil fuel ), there is currently neither the need nor the technical maturity to use the hemp oil, which is classified as high-quality, for energy purposes. In a study from 2007, the authors came to the conclusion that hemp oil is currently unsuitable for use in engines that are suitable for other vegetable oils due to insufficient oxidation stability and high coke residue compared to rapeseed oil , for example . There is a risk of technical problems and deterioration in emissions. An optimization of the manufacturing process or the addition of additives to improve the fuel properties remains open. However, it can be used as an additive to other vegetable oils.

As a feed additive

Hemp seed oil is an approved feed for animals. Various manufacturers have developed feed and feed additives based on hemp oil. The omega fatty acids have a positive effect on skin and fur and, similar to humans, improve the flow properties of the blood.

As a wood finish

Hemp oil is a 'drying oil' because it can polymerize into a solid form. Due to its polymer-forming properties, hemp oil is used alone or mixed with other oils, resins and solvents as an impregnating agent and varnish in wood finishing, as a pigment binder in oil paints and as a softener and hardener in fillers.

literature

  • Michael Carus et al .: Study on the market and competitive situation for natural fibers and natural fiber materials (Germany and EU). Gülzower Expert Discussions Volume 26 (PDF; 3.9 MB), Fachagentur Nachwachsende Rohstoffe eV 2008
  • Sabine Krist: Lexicon of vegetable fats and oils . 2nd Edition. Springer, 2013, ISBN 978-3-7091-1004-1 , pp. 251–257 ( limited preview in Google Book search).
  • Sabine Krist: Lexicon of vegetable fats and oils . Springer, 2008, ISBN 978-3-211-75606-5 , pp. 142–147 ( limited preview in Google Book search).
  • Geoff Talbot: Specialty Oils and Fats in Food and Nutrition. Woodhead, 2015, ISBN 978-1-78242-376-8 , p. 41 ff.

Web links

Wiktionary: Hemp oil  - explanations of meanings, word origins, synonyms, translations

swell

  1. ↑ a b c d e f g h i j k l m entry on hemp oil. In: Römpp Online . Georg Thieme Verlag, accessed on June 23, 2013.
  2. ↑ a b Sabine Krist
  3. ↑ Cary Leizer, David Ribnicky, Alexander Poulev, Slavik Dushenkov, Ilya Raskin: The Composition of Hemp Seed Oil and Its Potential as an Important Source of Nutrition. In: Journal of Nutraceuticals, Functional & Medical Foods. Volume 2, Issue 4, 2000, doi : 10.1300 / J133v02n04_04 , online (PDF; 784 kB), at eiha.org, accessed on May 2, 2017.
  4. ↑ a b c d Bavarian State Ministry for State Development and Environmental Issues: Vegetable oil- powered combined heat and power plants. Part 1, 2002, pp. 11, 18 online (PDF; 2.12 MB), lfu.bayern.de, accessed on April 30, 2017.
  5. ↑ a b c d e Peter Emberger, Rita Haas and others: Testing of hemp oil with regard to its properties as a fuel for engines suitable for vegetable oil. Technologie- und Förderzentrum (TFZ) , 2007, online (PDF; 1.51 MB), at nova-institut.de, accessed on May 2, 2017.
  6. ↑ Sibel Uluata, Nurhayat Özdemir: Antioxidant Activities and Oxidative Stabilities of Some Unconventional Oilseeds. In: J. Am. Oil Chem. Soc. 89 (4), 2012, pp. 551-559, doi : 10.1007 / s11746-011-1955-0 .
  7. ↑ Ernest Small: Cannabis: A Complete Guide. CRC Press, 2017, ISBN 978-1-4987-6163-5 .
  8. ↑ MA Rakusin: The investigation of petroleum and its products. Vieweg, 1906, Let Me Print 2013, ISBN 978-5-87762-073-5 (Reprint), pp. 31, 152.
  9. ↑ FAO statistics 2014 .
  10. ↑ DN Prjanischnikow : Special crop production. Springer, 1930, ISBN 978-3-642-98310-8 (reprint), p. 491.
  11. ↑ Sigrid Kerschbaum, Paul Schweiger: Changes in hemp oil during storage. State Institute for Plant Production Baden-Württemberg, February 13, 2001, ( page no longer available , search in web archives: (PDF; 101 kB) ).@1@ 2Template: Toter Link / www.ltz-bw.de
  12. ↑ JC Callaway: Hempseed as a nutritional resource: An overview . In: Euphytica . tape 140 , 2004, p. 65–72 , doi : 10.1007 / s10681-004-4811-6 (English, springer.com [accessed January 20, 2014]).
  13. ^ OV Grigoriev: Application of hempseed (Cannabis sativa L.) oil in the treatment of ear, nose and throat (ENT) disorders. In: J. Ind. Hemp. 7, 2002, pp. 5-15, doi : 10.1300 / J237v07n02_02 .
  14. ↑ Ivan Bócsa, Michael Karus, Daike Lohmeyer: The hemp cultivation - botany, varieties, cultivation and harvest, markets and product lines . Landwirtschaftsverlag, 2000, ISBN 3-7843-3066-5 , pp. 178-179.
  15. ↑ Hanf Journal: CannaFit for Horses , published on July 1st, 2011, accessed on March 18th, 2018
  16. ↑ Use of hemp oil - lets old wood shine in new splendor , published on 04/17/20, accessed on 05/18/20