12 Introduction to Renewable Biomaterials
Table 1.12Composition (%) (Michelsen, 1941) and heat value (MJ kg−^1 )
(Herrmann and Weber, 2011) of vegetable biomass and biomass
compounds.
CHNOS MJkg−^1
Vegetable biomass (average) 45 6 2 42 Traces 6.8
Wood 50 6 3 41 Traces 14.4–15.8
Peat 55 3 5 37 Traces 4.2
Linoleic acid 77 12 0 11 0 39.1
Glucose 40 7 0 53 0 15.6
Sucrose 43 6 0 51 0
Starch 44 6 0 50 0 17.5
Lignocellulose 44 6 0 50 0 10–25
(42–47%) and therefore a valuable feed additive. Soybean is cultivated worldwide with
highest acreage in the United States and Brazil.
Rapeseed (Brassica napus) delivers oil (40–50%) and protein (20–25%). Wild-type
(meaning the wild variety) rapeseed contains erucic acid (C 22 H 42 O 2 ) with a share of
25–50% among the fatty acids and some glucosinolate (glucoside containing sulfur
and nitrogen; a plant defense active against pests). Both compounds have a negative
nutritional effect, thus preventing the use of wild-type rapeseed in food and feed
applications. Plant breeding reduced the content of both compounds and today’s
cultivars produce 52–66% oleic acid, 17–25% linoleic acid, and 8–11% linolenic acid.
Rapeseed meal contains 33% protein and is a valuable feed component. Rapeseed is
cultivated especially in Europe.
Sunflower (Helianthus annuus) is an annual crop producing seeds with an oil
content of 50%. The main fatty acid components are linoleic acid (55–73%) and oleic
acid (14–34%). Extracted meal contains 40–45% and is used both in food and feed
applications. Sunflower is especially grown in Russia and Ukraine.
Oilpalm(Elaeis guineensis) is a palm tree cultivated in plantations. It produces up
to 15 years (first time 3 years after planting). Fatty acids accumulate in the fruit pulp
as well as in the seed kernel making up 45–50% of the fruit. The pulp fatty acids consist
of palmitic acid (44%; C 16 H 32 O 2 ), oleic acid (39%) linoleic acid (11%), and some minor
fatty acids. Palm kernel is especially rich in saturated fatty acids, mainly lauric acid
(48%; C 12 H 24 O 2 ) and stearic acid (16%; C 18 H 36 O 2 ). Malaysia and Indonesia are leading
producers of palm oil.
Jatropha (Jatropha) grows as plant, shrub, and tree. Trees that are cultivated for
producing vegetable oil grow even on poor soil. Fatty acids are deposited in the seed
to up to 30% consisting of 30–52% linoleic acid, 30–44% oleic acid, 15–17% palmitinic
acid, and 6–8% stearic acid. Because seeds contain toxic compounds Jatropha has
not been domesticated so far and yields are variable. The oil is highly suitable for fuel
applications and therefore Jatropha gains increasing industrial interest. Currently,
Jatropha oil is especially produced in India, Indonesia, and China. Table 1.13 lists the
global consumption of major vegetable oils.
