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A number of factors limit the use of beans and other pulses, including long soaking and cooking times necessary to adequately soften the beans, loss of valuable nutrients during bean preparation, low levels of the sulfur amino acids, low digestibility of unheated proteins, presence of antinutrients (e.g., lectins, trypsin inhibitors), high levels of phytic acid, various flatulence factors, and hard‐to‐cook (HTC) defects (Lucier et al. 2000; Lajolo and Genovese 2002; Uebersax et al. 1989, 1991; Maphosa and Jideani 2017). Table 1.7 presents a summary of constraints associated with legume utilization and possible solutions to minimize negative effects related to each constraint.

Numerous factors influence the quality of the final dry bean product. These include cultivar, seed source, agronomic conditions, handling and storage of the dry product, and processing procedures during cooking or canning. Quality changes in dry beans during cooking and processing are associated with their inherent physical components and chemical constituents (Hosfield and Uebersax 1980; Uebersax 1991). It must be noted that cooking and processing techniques improve the palatability, digestibility, and bioavailability through cellular separation and inactivation of antinutrional components.

Table 1.7. Typical constraints associated with legumes utilization, their negative effects and possible solutions.

Source: Maphosa and Jideani (2017).

Constraint	Negative effect	Solution
Trypsin and amylase inhibitors	Decrease protein and starch digestibility	Boiling dry beans generally reduces the content by 80–90%
Phytate	Chelates with minerals resulting in poor mineral bioavailability	Dehulling, soaking, boiling, steaming, sprouting, roasting and fermentation, autoclaving, gamma irradiation
Lectins, saponins	Reduced bioavailability of nutrients	Most destroyed by cooking, soaking, boiling, sprouting, fermenting
Oligosaccharides	Flatulence and bloating	Soaking, cooking, germination, and changing boiling water
Hard‐to‐cook phenomenon	Energy and time consumption	Soaking legumes before cooking
Low levels of sulfur‐containing amino acids	Incomplete protein source	Consuming in combination with cereals (high in sulfur‐containing amino acids)
Low iron bioavailability	Poor source of iron	Consuming in combination with vitamin C rich foods to increase iron absorption
Lack of convenient food applications	Boredom of eating the same food repeatedly	New and convenient product development using whole legumes or legume ingredients
Lack of awareness and understanding of nutritional benefits of legumes	Low intake of legumes	Increasing consumer awareness of the nutritional and health benefits of legumes
Reluctance to try a new food or to change eating habits	Low intake of legumes	Development of innovative, attractive legume‐based products to entice consumers

A comprehensive assessment of strategies and procedures used for processing dry beans is prerequisite to improved utilization of dry beans. Implementation of a given protocol can be maximized through an understanding of the physical and chemical components, the inherent constraints and diversified processing techniques available to develop economically viable alternative and innovative products (Uebersax et al. 1991). Improved utilization of dry beans can be maximized through an understanding of how physical and chemical components function and react under given process conditions. Further, variability in the physico‐chemical composition of dry beans occurs, warranting research and quality control programs directed to provide a consistent product possessing characteristics of acceptable flavor, bright color, attractive appearance, uniform texture, and high nutritional quality.