Recently, plant proteins have gained great importance due to the increasing demand for protein sources1. In this review, we are going to focus on the nutritional value of hempseed, one of the plant protein sources, and its health benefits.
Hemp, one of the belongings of the family Cannabaceae, has an important place in our lives for being a crucial source of textiles, food, medicine, cosmetics, and automotive2. Throughout history, the cultivation of hemp (Cannabis Sativa L.) has been controversial and limited by dozens of countries due to the use of the intoxicating compound tetrahydrocannabinol (THC)3. For this reason, to legally cultivate hemp, the plants must contain less than %0.2 or %0.3 (dry weight) of tetrahydrocannabinol (THC)4. Nevertheless, hemp has been replaced by other plant seeds and synthetics in the textile, food industry, and many other areas due to its controversial history4.
Cannabis Sativa is one of the food plants that have been removed from their natural habitat and been changed the genetic material to apply to the needs of human beings4. For millennia, hemp was cultivated as a fibre source and as an oilseed crop. Due to its high nutritional value, it also became very popular in the food industry4. Although it is not involved in the development of cells and provides energy for the human body, It plays an important role in human growth and metabolism4. In addition to its nutritional value, dietary supplementation of hempseed oil offers health benefits on lipid metabolism, cardiovascular health, dermatological disease and so forth4.
Hempseeds are usually round and smooth, nearly spherical in dark red-brown or dark grey colour, with the size ranging from 2.5 to 5 mm in diameter5. Hempseeds relatively contain 30% to 35% oil, 25% to 30% protein (similar to the protein content of soybeans2), 20% to 30% carbohydrates, substantial amounts of fibres, provitamin A vitamin E and minerals such as phosphorus, potassium, magnesium and so on. The edible portion of hempseed contains 46.7% oil and 35.9% protein if it’s hull removal. There are also some antinutritional compounds in the concentration of hempseed such as phytic acid, and trypsin inhibitors which are presented in many small quantities3,4.
The fact that hemp seeds contain a small amount of saturated fatty acids indicates that the seed has a quality oil content, nevertheless, omega-3, one of the unsaturated fatty acids, represents in hempseeds2. It has been also well known for its essential amino acid composition, especially arginine which is very important for human health is remarkably high, yet 60% to 80% content of hempseed protein includes edestin (globulin)2,3. By using X-ray crystallography techniques, It is shown that edestin structure is very similar to the structure of hexamer (a compound containing six subunits6) of soy glycinin, incorporate to six identical subunits, each consisting of acidic (AS) and basic (BS) subunit linked by one disulphide bond3.
In the image above; in section A, you can see SDS–PAGE profiles of HPI (hempseed protein isolate)in comparison with SPI (soy protein isolate) in reduced (presence) and unreduced (absence) of 2‐mercaptoethanol. “AS and BS represent the acidic and basic subunits of soy glycinin, respectively, and α’, α, and β represent the corresponding major subunits of soy β‐conglycinin. In section B, SDS–PAGE in reducing conditions of hemp flour and HPI showing edestin dominating in both samples”3.
Although there were a few kinds of research on the nutritional value of hempseed for many years, in the last two decades in scientific research, hempseed has drawn attention and now it is known that hempseed protein has the excellent nutritional quality and health benefits.
- Yavuz M., Özçelik B. 17 Dec 2016. “ Bitkisel Protein İzolatlarının Fonksiyonel Özellikleri”, Gıda Mühendisliği Bölümü, Kimya Metalürji Fakültesi, İstanbul Teknik Üniversitesi, 424-430.
- Göre, M. and O. Kurt, Bitkisel Üretimde Yeni Bir Trend: Kenevir. International Journal of Life Sciences and Biotechnology, 2021. 4(1): p. 138-157. DOI: 10.38001/ijlsb.789970
- Wang Q., Xiong Y. 09 May 2019. “ Processing, Nutrition, and Functionality of Hempseed Protein: A review. https://doi.org/10.1111/1541-4337.12450
- Zu Y., Li J., Zhao J., Wang W., Griffin J., Li Y., Bean S., Tilley M., Wang D. 08 August 2020. “Hempseed as a nutritious and healthy human food or animal feed source: a review”. https://doi.org/10.1111/ijfs.14755
- Leonard W., Zhang P., Ying D., Fang Z. 19 December 2019. “Hempseed in food industry: Nutritional value, health benefits, and industrial applications. https://doi.org/10.1111/1541-4337.12517
Figure Reference: Wang Q., Xiong Y. 09 May 2019. “ Processing, Nutrition, and Functionality of Hempseed Protein: A review. https://doi.org/10.1111/1541-4337.12450