Traditional and Emerging Feedstocks for Food and Industrial Bioproduct Manufacturing - Food and Industrial Bioproducts and Bioprocessing - page 16

Table 1.2 Rapeseed/canola, soybean, sunflower and cottonseed production in 2008 (million metric tons).

Rapeseed/canola Soybean Sunflower Cottonseed

World 58.1 World 230.6 World 35.7 World 65.4

Canada 12.6 USA 80.7 Russian Federation 7.3 China 15.0

China 12.1 Brazil 59.2 Ukraine 6.5 India 7.6

India 5.8 Argentina 46.2 Argentina 4.7 Pakistan 3.8

Germany 5.2 China 15.6 China 1.8 Brazil 2.5

cyst nematode resistance are some of the criteria used to select suitable soybean varieties for
production. Soybeans are classified based on their agronomic properties and hilum color.
Soybean development is affected by temperature, day length and hours of sunshine. Varieties
adapted to a particular region are assigned a maturity group number. During the summer,
day length increases from south to north in United States. Varieties in maturity group 00 are
adapted to the northernmost regions and those in group VIII to the southernmost region. As
the maturity group number increases, the lengths of the vegetative and reproductive stages
of development are extended.
The hilum is the point at which the soybean seed attaches to the pod. Soybean hilum
color can be yellow, imperfect yellow, grey, buff, brown, black or imperfect black. Yellow
hilum soybeans are generally preferred for the export market. Soybeans are also classified
as food and oil beans based on utilization.
Seed coat and hilum color, bean size and grade, organoleptic properties and chemical
composition are important characteristics for selection of soybeans for food applications.
For example, Japanese food manufacturers prefer soybeans with clear to light colored hilum,
large seed size (18 g/100 seeds), creamy white cotyledons and 40% or higher protein content
beans for making miso and tofu. Many soybean varieties have been developed for specific
food applications, such as tofu, natto, miso and edamame beans (Liu, 1997).
Human health and environmental concerns about genetically modified organism (GMO)
lead to consumer demand for identity-preserved and non-GMO soybeans. Identity
preservation is the segregation of a crop variety from planting through to delivery to the end
user. This concept is used in food-grade soybeans production. Soybeans contain at least
three lipoxygenase isozymes, which are responsible for the production of unpleasant grassy
and beany flavors. In the early 1990s, soybeans lacking lipoxygenase enzyme and having
less bean-like flavor were developed (Moreira et al ., 1993 ). Both traditional breeding
and genetic engineering tools have also been used to improve other soybean properties.
Soybeans with higher protein, sucrose and fermentable sugar content and yield and lower
oligosaccharide content and altered oil fatty acid compositions have been developed. Recent
studies focus on increasing stearidonic acid (Eckert et al ., 2006 ) and

-tocopherol contents
(Van Eenennaam et al ., 2003), removal of the Gly m Bd 30 K protein, which is a soybean
allergen (Herman et al ., 2003), and reduction of phytic acid (Shi et al ., 2007 ) in soybeans.

α

1.3.2.2 Chemical composition

Similar to the other crops, soybean chemical composition varies significantly with
environmental and agronomic conditions and variety. It has been reported that the oil content
of soybeans varied more than its protein content from year to year (Ren et al ., 2009 ). Draught
stress caused a significant increase in soybean protein content while oil content decreased.