(Girgih et al. 2011a, 2014; Salentijn et al. 2015). Botanically it is distinct from all
other plants and is readily recognised. However, the botanical classification of hemp
is still a controversial topic (Allegret 2013; Chabbert et al. 2013).
Hemp is one of the anciently cultivated crops, with its initial cultivation dating
back to 4000–6000 years ago. Although there is no written record, it is believed that
hemp might have been grown in China 20,000 years ago (Przybylski 2006). Initially,
hemp was valued as a source of fibre, but by the sixteenth century, it became an
important cash crop in Europe and was widely utilised for both its fibre and its seeds
(Johnson 1999). Hemp was introduced to America and New England, in 1645.
However, in the late 1800s, hemp-based industries in the United States began to
decline because of the technical advancements in cotton ginning, leading to reduced
labour and consequent replacement of hemp-derived products with cotton products
(Johnson 1999).
Cannabis is believed to be an Asiatic plant. There is no concerted agreement
among botanists as to where the wild plant originally grew and where its cultivation
first began. However, evidence of the use of hemp fibres has been found in Neolithic
records in northern China (Lu and Clarke 1995). The oldest existing documents that
describe the use of hempseed as both food and medicine are from China, where
Cannabis stalks, leaves and seeds were found in tombs that are over 4500 years old
(Callaway 2004).
The earliest or the primary use of the plant was probably for its fibres. It was the
only fibre plant known to ancient people in northern China, north-eastern China and
eastern Siberia. In addition, it is reported that patterns of woven material (possibly
Cannabis fibres) in the form of nets were used for trapping small animals. The
tremendous cultural importance attached to hemp as a textile fibre is indicated by the
practice of wearing hemp fabric clothes while mourning the death of a parent or
parents, since Confucian times (Mwaikambo and Ansell 2002).
There is no easy way to distinguish between wild and spontaneous or adventitious
and semi-cultivated or cultivated plants. Therefore, further progress in the determination of the geographical origin of the plant is yet to be carried out. The influence of
man must be considered along with the botanical facts to unveil the complex nature
of the plant (Mwaikambo and Ansell 2002). By providing a nutritious food from its
seed, a durable fibre from its stalk and efficacious medicine from its flower and
leaves, Cannabis has assisted in the human development like no other plant species
(Zuardi 2006).
15.2 Production
The inception of hempseed oil production begins with low temperature (<25
C)
air-drying of fresh and well-cleaned seeds. This drying unit operation is monitored
over several days so as to reduce the moisture content of the seeds to 10% before
proceeding for storage or processing (Callaway 2004; Callaway and Pate 2009).
However, mould growth between the time of harvest and drying is a primary
374
I. Syed et al.
other plants and is readily recognised. However, the botanical classification of hemp
is still a controversial topic (Allegret 2013; Chabbert et al. 2013).
Hemp is one of the anciently cultivated crops, with its initial cultivation dating
back to 4000–6000 years ago. Although there is no written record, it is believed that
hemp might have been grown in China 20,000 years ago (Przybylski 2006). Initially,
hemp was valued as a source of fibre, but by the sixteenth century, it became an
important cash crop in Europe and was widely utilised for both its fibre and its seeds
(Johnson 1999). Hemp was introduced to America and New England, in 1645.
However, in the late 1800s, hemp-based industries in the United States began to
decline because of the technical advancements in cotton ginning, leading to reduced
labour and consequent replacement of hemp-derived products with cotton products
(Johnson 1999).
Cannabis is believed to be an Asiatic plant. There is no concerted agreement
among botanists as to where the wild plant originally grew and where its cultivation
first began. However, evidence of the use of hemp fibres has been found in Neolithic
records in northern China (Lu and Clarke 1995). The oldest existing documents that
describe the use of hempseed as both food and medicine are from China, where
Cannabis stalks, leaves and seeds were found in tombs that are over 4500 years old
(Callaway 2004).
The earliest or the primary use of the plant was probably for its fibres. It was the
only fibre plant known to ancient people in northern China, north-eastern China and
eastern Siberia. In addition, it is reported that patterns of woven material (possibly
Cannabis fibres) in the form of nets were used for trapping small animals. The
tremendous cultural importance attached to hemp as a textile fibre is indicated by the
practice of wearing hemp fabric clothes while mourning the death of a parent or
parents, since Confucian times (Mwaikambo and Ansell 2002).
There is no easy way to distinguish between wild and spontaneous or adventitious
and semi-cultivated or cultivated plants. Therefore, further progress in the determination of the geographical origin of the plant is yet to be carried out. The influence of
man must be considered along with the botanical facts to unveil the complex nature
of the plant (Mwaikambo and Ansell 2002). By providing a nutritious food from its
seed, a durable fibre from its stalk and efficacious medicine from its flower and
leaves, Cannabis has assisted in the human development like no other plant species
(Zuardi 2006).
15.2 Production
The inception of hempseed oil production begins with low temperature (<25
C)
air-drying of fresh and well-cleaned seeds. This drying unit operation is monitored
over several days so as to reduce the moisture content of the seeds to 10% before
proceeding for storage or processing (Callaway 2004; Callaway and Pate 2009).
However, mould growth between the time of harvest and drying is a primary
374
I. Syed et al.