Hemp oil

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Hemp oil or hempseed oil is obtained by pressing hemp seeds. Cold pressed, unrefined hemp oil is dark to clear light green in color, with a nutty flavour. The darker the color, the grassier the flavour. It should not be confused with hash oil, a tetrahydrocannabinol-containing oil made from the Cannabis flower, hailed by some[1] for its medicinal qualities.[2]

Description[edit]

Refined hempseed oil is clear and colorless, with little flavor and lacks natural vitamins and antioxidants. Refined hempseed oil is primarily used in body care products. Industrial hempseed oil is used in lubricants, paints, inks, fuel, and plastics. Hempseed oil has found some limited use in the production of soaps, shampoos and detergents. The oil is of high nutritional value because of its 3:1 ratio of omega-6 to omega-3 essential fatty acids,[3] which matches the balance required by the human body.[4] It has also received attention in recent years as a possible feedstock for the large-scale production of biodiesel.[5][6] There are a number of organizations that promote the production and use of hempseed oil.[7]

Manufacture[edit]

Hempseed oil is manufactured from varieties of Cannabis sativa that do not contain significant amounts of tetrahydrocannabinol (THC), the psychoactive element present in the cannabis plant. This manufacturing process typically includes cleaning the seed to 99.99% before pressing the oil. There is no THC within the hempseed, although trace amounts of THC may be found in hempseed oil when plant matter adheres to the seed surface during manufacturing. The modern production of hempseed oil, particularly in Canada, has successfully lowered THC values since 1998.[8] Regular accredited sampling of THC in Canadian hemp seed oil shows THC levels usually below detection limit of 4 ppm (parts per million, or 4 mg/kg). Legal limit for THC content in foodstuffs in Canada is 10 ppm[citation needed]. Some European countries have limits of 5ppm or none-detected, some EU countries do not have such limits at all.

Nutrition[edit]

About 30–35% of the weight of hempseed is an edible oil that contains about 80% as essential fatty acids (EFAs); i.e., linoleic acid, omega-6 (LA, 55%), alpha-linolenic acid, omega-3 (ALA, 22%), in addition to gamma-linolenic acid, omega-6 (GLA, 1–4%) and stearidonic acid, omega-3 (SDA, 0–2%).

The proportions of linoleic acid (LA) and alpha-linolenic acid (ALA) in one tablespoon per day (15 ml) of hempseed oil easily provides human daily requirements for EFAs[citation needed]. Advocates of hempseed oil hold that unlike flaxseed oil, hempseed oil can be used continuously without developing a deficiency or other imbalance of EFAs. This has supposedly been demonstrated in a small clinical study of 14 people, where the daily ingestion of flaxseed oil "resulted in a higher proportion of ALA" in serum cholesteryl esters and triglycerides as compared with the ingestion of hempseed oil. However, the hempseed oil "resulted in higher proportions of both LA and gamma-linolenic acid" as compared with the flaxseed oil ingestion, and the conclusion talks of "only minor effects on concentrations of fasting serum total or lipoprotein lipid".[9]

In common with other oils, hempseed oil provides 9 kcal/g. Compared with other culinary oils it is low in saturated fatty acids.[10]

Highly unsaturated oils, and especially poor quality oils, can spontaneously oxidize and turn rancid within a short period of time when they are not stored properly; i.e., in a cool/cold, dark place, preferably in a dark glass bottle. Hempseed oil can be frozen for longer periods of storage time. Preservatives (antioxidants) are not necessary for high-quality oils that are stored properly.

Hempseed oil has a relatively low smoke point and is not suitable for frying. Hempseed oil is primarily used as a food oil and dietary supplement, and has been shown to relieve the symptoms of eczema[11]

Comparison to other vegetable oils[edit]

Vegetable oils[12][13]
Type Processing
Treatment
Saturated
fatty acids
Monounsaturated fatty acids Polyunsaturated fatty acids Smoke point
Total mono[12] Oleic acid
(ω-9)
Total poly[12] linolenic acid
(ω-3)
Linoleic acid
(ω-6)
Avocado[14] 11.6 70.6 13.5 1 12.5 249 °C (480 °F)[15]
Canola[16] 7.4 63.3 61.8 28.1 9.1 18.6 238 °C (460 °F)[17]
Coconut[18] 82.5 6.3 6 1.7 175 °C (347 °F)[17]
Corn[19] 12.9 27.6 27.3 54.7 1 58

232 °C (450 °F)[20]

Cottonseed[21] 25.9 17.8 19 51.9 1 54 216 °C (420 °F)[20]
Flaxseed/Linseed[22] 9.0 18.4 18 67.8 53 13

107 °C (225 °F)

Hempseed[23] 7.0 9.0 9.0 82.0 22.0 54.0

166 °C (330 °F)[24]

Olive[25] 13.8 73.0 71.3 10.5 0.7 9.8 193 °C (380 °F)[17]
Palm[26] 49.3 37.0 40 9.3 0.2 9.1 235 °C (455 °F)
Peanut[27] 20.3 48.1 46.5 31.5 31.4 232 °C (450 °F)[20]
Safflower[28] 7.5 75.2 75.2 12.8 0 12.8 212 °C (414 °F)[17]
Soybean[29] 15.6 22.8 22.6 57.7 7 51 238 °C (460 °F)[20]
Sunflower (< 60% linoleic)[30] 10.1 45.4 45.3 40.1 0.2 39.8

227 °C (440 °F)[20]

Sunflower (> 70% oleic)[31] 9.9 83.7 82.6 3.8 0.2 3.6

227 °C (440 °F)[20]

Cottonseed[32] Hydrogenated 93.6 1.5 0.6 0.3
Palm[33] Hydrogenated 88.2 5.7 0
Soybean[34] Partially hydrogenated 14.9 43.0 42.5 37.6 2.6 34.9
Values as percent (%) by weight of total fat.

Wood finish[edit]

Hemp oil is a "drying oil", as it can polymerize into a solid form. Due to its polymer-forming properties, hemp oil is used on its own or blended with other oils, resins, and solvents as an impregnator and varnish in wood finishing, as a pigment binder in oil paints, and as a plasticizer and hardener in putty. It has uses similar to linseed oil and characteristics similar to tung oil.[35]

Gallery[edit]

See also[edit]

References[edit]

  1. ^ "THC, Laboratory/Animal/Preclinical Studies, Anti-tumor Effects". National Cancer Institute at the National Institutes of Health. April 2014. Retrieved April 3, 2014. 
  2. ^ "Hemp-Oil Medicine". High Times. November 2013. Archived from the original on December 12, 2013. Retrieved December 7, 2013. 
  3. ^ Callaway, J. C. (2004). "Hempseed as a nutritional resource: An overview". Euphytica. 140: 65–72. doi:10.1007/s10681-004-4811-6. Retrieved 20 January 2014. 
  4. ^ "Hemp Oil". InnVista. November 2005. Archived from the original on September 17, 2012. Retrieved November 18, 2006. 
  5. ^ Agua Das (November 16, 1997). "Hemp Oil Fuels & How to Make Them". HempFarm.com. Archived from the original on October 29, 2006. Retrieved November 18, 2006. 
  6. ^ see Soybean Car
  7. ^ "Hemp Farm". Retrieved November 18, 2006. 
  8. ^ Holler JM, et al.(2008) delta-9-Tetrahydrocannabinol Content of Commercially Available Hemp Products. Journal of Analytical Toxicology 32: 428–432
  9. ^ Schwab, U. S.; Callaway, J. C.; Erkkilä, A. T.; Gynther, J; Uusitupa, M. I.; Järvinen, T (2006). "Effects of hempseed and flaxseed oils on the profile of serum lipids, serum total and lipoprotein lipid concentrations and haemostatic factors". European Journal of Nutrition. 45 (8): 470–7. doi:10.1007/s00394-006-0621-z. PMID 17103080. 
  10. ^ King's College Review of Nutritional Attributes of Cold Pressed Hemp Seed Oil Archived February 26, 2009, at the Wayback Machine.
  11. ^ Callaway, J.; Schwab, U.; Harvima, I.; Halonen, P.; Mykkänen, O.; Hyvönen, P.; Järvinen, T. (2005). "Efficacy of dietary hempseed oil in patients with atopic dermatitis". Journal of Dermatological Treatment. 16 (2): 87–94. doi:10.1080/09546630510035832. PMID 16019622. 
  12. ^ a b c "US National Nutrient Database, Release 28". United States Department of Agriculture. May 2016.  All values in this column are from the USDA Nutrient database unless otherwise cited.
  13. ^ "Fats and fatty acids contents per 100 g (click for "more details") example: avocado oil; user can search for other oils". Nutritiondata.com, Conde Nast for the USDA National Nutrient Database, Standard Release 21. 2014. Retrieved 7 September 2017.  Values from Nutritiondata.com (SR 21) may need to be reconciled with most recent release from the USDA SR 28 as of Sept 2017.
  14. ^ "Avocado oil, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  15. ^ What is unrefined, extra virgin cold-pressed avocado oil?, The American Oil Chemists’ Society
  16. ^ "Canola oil, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  17. ^ a b c d Katragadda, H. R.; Fullana, A. S.; Sidhu, S.; Carbonell-Barrachina, Á. A. (2010). "Emissions of volatile aldehydes from heated cooking oils". Food Chemistry. 120: 59. doi:10.1016/j.foodchem.2009.09.070. 
  18. ^ "Coconut oil, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  19. ^ "Corn oil, industrial and retail, all purpose salad or cooking, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  20. ^ a b c d e f Wolke, Robert L. (May 16, 2007). "Where There's Smoke, There's a Fryer". The Washington Post. Retrieved March 5, 2011. 
  21. ^ "Cottonseed oil, salad or cooking, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  22. ^ "Linseed/Flaxseed oil, cold pressed, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  23. ^ "Efficacy of dietary hempseed oil in patients with atopic dermatitis". Journal of Dermatological Treatment. 2005. Retrieved 25 October 2017. 
  24. ^ https://www.veghealth.com/nutrition-tables/Smoke-Points-of-Oils-table.pdf
  25. ^ "Olive oil, salad or cooking, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  26. ^ "Palm oil, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  27. ^ Vegetable Oils in Food Technology (2011), p. 61.
  28. ^ "Safflower oil, salad or cooking, high oleic, primary commerce, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  29. ^ "Soybean oil, salad or cooking, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  30. ^ "Sunflower oil, less than 60% of total fats as linoleic acid, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  31. ^ "Sunflower oil, high oleic - 70% or more as oleic acid, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  32. ^ "Cottonseed oil, industrial, fully hydrogenated, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  33. ^ "Palm oil, industrial, fully hydrogenated, filling fat, fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  34. ^ "Soybean oil, salad or cooking, (partially hydrogenated), fat composition, 100 g". US National Nutrient Database, Release 28, United States Department of Agriculture. May 2016. Retrieved 6 September 2017. 
  35. ^ http://badger-canoe-paddles.blogspot.ca/2011/06/badger-wood-oil-why-hemp.html