The USDA grade standards are established for lentils and are employed in commercial trade. The grade classes are designated as “US #1,” “US #2,” and “US #3.” Grading factors for these standards include the following:
Defective lentils, % (total = weevil‐damaged + heat damaged + damaged + splits); “US #1” ≤ 2.0%, “US #2” ≤ 3.5%, and “US #3” > 5.0%
Foreign material, % total and stones (“US #1” ≤ 0.2%, “US #2” < 0.5%, and “US #3” > 0.5)
Skinned lentils (≥ 3/4 seed coat missing)
Contrasting lentils – both size and color deviations from the predominant type (“US #1” ≤ 2.0%, “US #2” < 4.0%, and “US #3” > 4.0%). Lots with greater than 4.0% are subject to a limiting rule, which states that the lot may not be graded greater than “US #3”;
Minimum requirements for color use the following terminology: “US #1” = good, “US #2” = fair, “US #3” = poor.
Further, special grades for lentils may be designated by two size classes based on round hole sieve classification tolerances as follows: large lentils (3.0% <15/64 inch) and small lentils (95% > 15/64 inch, 80% > 12/64 inch, 3.0% < 9/64 inch). This size grade terminology is designated with the US grade (USDA 2017b).
SEED CERTIFICATION
The integrity of bean cultivars depends on bean seed propagation being secure and “true to type.” Without a secure seed supply, the identity of a commercial cultivar will likely “drift” and as such, the genetic and phenotypic traits will differ over time (generations). Strict quality control must be maintained to secure bean genetics in commercial seed production. This process is conducted under governmental (national/federal, state/provincial) and/or private sector certification programs.
The certification programs are governed by minimum standards set by members of the Association of Official Seed Certification Agencies (AOSCA), with the opportunity to adopt more stringent requirements on a state‐by‐state basis (Novak and Moore 2015). The policies and procedures for the Idaho Crop Improvement Association (www.idahocrop.com) serve as a model for a secure seed quality program. Defined protocol and standards for growing, harvesting, and managing the seed by identify preserved lots are required for certification. Such programs commonly designate various levels of certification (e.g., foundation, registered, and certificated) based on the intensity of the production control tolerances applied. Foundation seed is usually produced by the originator of the variety and sold to seed producers to produce Registered seed. Registered seed is grown by seed producers to increase the supply for production of Certified seed. Certified seed is to be used for commercial production and in most cases cannot be used to produce another generation of certified seeds (Novak and Moore 2015).
The key elements of certified seed production include: grower application requirements, land requirements (e.g., freedom of bacterial blight), crop management (e.g., weed control and specific requirements for disease tolerance), and seed standards (e.g., pure seed, contrasting classes, weed seed, inert matter, splits and cracks, and germination percentage). Finally, strict control of harvesting and seed handling are used to assure integrity of the seed lots. Bean seed certification has had a regional and global impact on the integrity of cultivars and overall improvement of bean productivity (Idaho Bean Certification 2018).
SUMMARY
Market classes of dry beans are diverse in appearance and well defined for commercial trade. Each commercial class is handled as a discrete and independent bean type possessing differentiated characteristics and variable economical value. The extensive agronomic cultivation and the traditional use of beans among different cultures and their importance to global food supplies are well recognized and frequently provide the origins for enhanced value‐added products. Additionally, beans are commonly associated with high nutritional value and characteristic culinary appeal and comprise a broad array of distinctive sizes, shapes, and colors. These variations among bean classes provide distinctive culinary choices and a range of processed products that deliver simple and attractive meal options. The greatest economic value of beans is associated with the use of high‐quality intact whole seeds. The physiological structure and anatomical features of the bean seed (seed coat, cotyledon, and embryo) are each distinctive component that influence quality and must be considered in selecting and optimizing approaches for handling, preparation, and end‐product use. The composition of seed inherently influences food value, particularly the diverse phenolic content of bean seed pigments. Phenolic compounds influence the color and appearance and may directly influence bean consumption and nutrient bioavailability. Effective domestic and international trade requires grades and standards that provide a uniform means of describing the quality attributes of dry beans.
REFERENCES
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