A Maritime Industrial Hemp Product Marketing Study

Appendix G

Glossary of Terms

We have a prepared a list of some of the terms that exist in the world of hemp. These are:

• Bast Fibre: The woody inner core of the stalk, typically about 20-30% of the stalk. Bast fibres come in two varieties: primary, which are long in length and low in lignin content, and secondary which are medium lengths, higher in lignin when the plants are grown in less dense stands.

• Biomass Fuels: Fuels made out of plants versus fossil fuels such as coal and petroleum.

• Cold-pressing of Oilseeds: Edible oils such as canola, flax and hemp contain omega-3 and omega-6 essential fatty acids and as such are easily damaged by exposure to heat, light and oxygen. Many companies cold-press oil for the health and natural foods markets in a light and oxygen free environment and then place the oil in oxygen-free dark amber glass bottles.

• EFAs: Essential fatty acids. Hemp contains high levels of two important EFAs (see GLA and ALA).

• Functional Foods/Neutraceuticals: These foods are similar in appearance to conventional food but has been demonstrated to have physiological benefits and/or to reduce the risk of chronic disease in addition to providing basic nutritional functions. They are products isolated or purified from foods and generally sold in medicinal forms. They are considered by many to be the next wave in the food industry. Borage, flax seed, hemp and fish oils are essential fatty acid supplements which are considered to be netraceuticals.

• Grain versus Seed: The term grain refers to the non-viable seeds produced by a hemp crop and used in food products or processed for oil. Seed is used for planting a new crop.

• GLA & ALA: Hemp contains both of these essential fatty acids. They are gamma-linolenic acid (found in borage) and alpha-linolinic acid (also found in flax).

• Dehulling: The removal of the crunchy skin from hemp grain.

• Hemp Family: Bast fibre plants including jute hemp (also called manila hemp), sisal hemp and cannabis hemp.

• Hempseed Cake: The remaining seed material after oil extraction has occurred. It can be processed into a number of food products.

• Hempys/Hempsters: The name given to pro-hemp advocates and often used to denote pro-marijuana advocates.

• Hemp versus Marijuana: Hemp and marijuana are both classified by taxonomists as Cannabis sativa, a species with hundreds of varieties. C. sativa is a member of the mulberry family. Hemp is bred to maximize fiber, seed and/or oil, while marijuana varieties seek to maximize THC. Industrial hemp must contain less than 0.3% THC.

• Hurds: Known as chenvotte in French is the woody inner portion of the plant (what is left after the bast fibres have been removed from the stalk. Hurds account for about 70-80% of the plant by volume. Though the fibre are shorter, the lignin content of hurds is similar to that of wood.

• Lignin: A sticky, dark and water-resistant covering which gives strength to the plant. It presents problems in the manufacture of paper in that most of it must be removed thus the high chemical used in paper mills.

• Long-Line Fibre Processing for Textiles: Once retted, long fibres for textiles are produced by the following processes:

  • dried stalks pass through a series of rollers (a breaker) to break the woody core into pieces but not the long bast fibre bundles.

  • Two methods are available: A scutcher then uses rotary blades to separate the hurds from the short tow fibres and the long fibres. A decorticator uses crushing rollers and pin rotors to separate the fibres from the hurds.

  • The long fibres are then combed with wire pins of increasing fineness and closeness.

  • Cottonizing (either mechanically or chemically separating the individual cells) produces the softest fibres.

  • To convert to yarn, the combed hemp is overlapped and drawn out a number of times so that it forms one continuous strand called a sliver. The sliver is then drawn further and a slight amount of twist added, called roving. The roving is then drawn again into a finer strand and then wet spun into a fine yarn.

• Matting: The production of non-woven mats and fleeces for composites, geotextiles, and insulation mats.

• Monoecious/Dioecious: A monoecious plant contains both sexes which ripens at one time. Contrasts with dioecious where the plant has male and female parts that ripen at different times. Some plants are considered unisexual.

• Pulping: Pulping is the process whereby wood or non-wood fibres are either chemically, mechanically, chemi-mechanically, thermal mechanical or by solvent pulping turned into a slurry for use in paper-making. There are many grades of paper, each requiring particular slurry characteristics. Chemical pulping is most often used with wood chips. Chemicals are added to the wood and/or fibre product and it is cooked in a pressure cooker. Once the lignin is dissolved the liquid that is left is called a black liquor. Chemical recovery procedures are used and the resulting liquid from this process is often burned away. It is expensive for non-wood fibres such as hemp which contain high lignin content because sometimes a significant portion of the non-wood fibre is lost yet is it paid for, transported and handled is lost.

• Refining Processes: Processes to further process hemp after retting. These include such activities as decortication, scutching and combing.

• Retting: Controlled rotting of the stalks after harvesting to break down pectins and hemi-cellulose which hold the bast cells to the rest of the stem. Once the binding agent is broken down, the fibre and the stalk are easily separated. There are several different retting procedures that can be used.

  Dew Retting is the traditional method induced by frequent rains and dews. After the hemp stalk is cut, it is spread evenly on the ground to allow decomposition of the pectin. There is a fine line between retting and rotting. If continued wet weather prevents the straw in the field from being lifted at the proper time, it becomes over-retted and is of little value. Without the proper equipment dew retting is labour intensive. It may take only one to two weeks if the weather is warm and humid, but usually four to five weeks are required. The retting process is followed by a period of drying and the stalks are baled are then stored for further processing. The fibre from dew retted hemp is light brown in colour and rather coarse. It is used primarily for twine, cordage and fine paper.

  In Water Retting, Bundles of hemp are submerged in clear water low in calcium and chlorides allowing bacterial activity to break down the pectin. The average retting period is seven to 10 days after which retted bundles are then rinsed, washed, sun-dried and stored for fibre extraction. Although water retting is more costly than dew retting, the fibre is of a higher quality. It can be combed one or more times, refined, dyed, spun and woven into whatever extent is required for cable, rope, string, thread, cloth, etc.

  Warm Water Retting is similar to water retting but the hemp is soaked for 24 hours then new water is added and brought to an elevated temperature for about two to three days. A very uniform, clean fibre is produced.

  Green Retting is, as the name implies, green stalks are mechanically processed to separate the fibre from the stalk. The high quality fibre can be refined for the textile industry while the remaining stalk can be used in the paper and fibre board industries.

  Chemical Retting consists of placing hemp stalks in a processing tank where chemical agents are used to dissolve the pectin. By maintaining a constant processing temperature the retting time can be reduced to 48 hours while producing a very high quality fibre.

  After the retting process the hemp fibre and the stalk are loosely held together and must be decorticated, scutched, hackled and combed to remove the remaining pieces of stalk, broken fibres and extraneous material. Mechanical decortication equipment can be used in conjunction with turbine scutchers to separate the fibre and the non-fibrous portion of the stalk.

• THC: Delta 9 tetrahydrocannabinol, the primary psychoactive ingredient in marijuana but naturally produced to varying degrees in nearly all hemp cultivars. By law, hemp must contain less than 0.3% THC whereas some marijuana cultivars contain over 3% and there may be greater than 40% THC in specific parts of the plant. Currently, derivatives of hempseed or grain such as seed oil or cake must contain less than 10 micrograms of THC per gram.

• Tow: Hemp fibres derived from the scutching and hackling process in textiles. They are separated from the long fibres, are shorter and contain mostly wood, dirt particles or trash.

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This page last updated on 18 April 1999.