The consumer demand for organically produced dry beans (Phaseolus vulgaris L.) continues to increase in the U.S. Organic farmers are faced with production and harvest challenges that impact the processing and end-use quality of dry beans. One major challenge is seed coat mechanical damage induced during harvest, which is a concern for both organic and conventional growers, but the latter has more tools to manage harvest to reduce the impact of the damage. The goal of this research is to improve organic dry bean end-use quality by exploring the genetic variability for mechanically induced seed coat damage, developing enhanced end-use product processing methods, and investigating the variations in seed quality related characteristics. Kidney and black bean market classes are the focus of this work due to their importance in organic production and challenges with end-use quality, especially seed coat splitting and canning quality. Genetic variability for seed coat splitting was evaluated in a collection of 61 kidney beans from three market classes including dark red kidney (DRK), light red kidney (LRK), and white kidney (WK) beans. The beans were harvested under two conditions to induce mild and severe seed coat damage as well as the downstream processing quality of the beans. LRK was found to be more susceptible to seed coat damage than the other two market classes with the highest average seed coat check (SCC) severity score. Genotypes less susceptible to seed coat damage than others were identified within each market class. Seed coat thickness was found not to be a good indicator for SCC severity. SCC severity scores and canning quality appearance scores were found to be negatively correlated. SCC severity score of combine threshed seeds can be used as a selection factor in variety improvement for resilience to mechanical damage. Canning and pouch processing methods were further explored as means to add value to organically produced beans. Pilot-scale pouch and canning processing protocols were developed and updated for use in dry bean breeding programs. The protocols included innovative virtual quality evaluation methods and methods to improve the processing quality of organic dry beans. Both methods were utilized with dry beans from different market classes to test the methods and identify the expected variations in processing quality. A harvest survey was conducted with participation from Michigan bean growers. Nine out of 22 black bean samples had a higher than 20% SCC percentage which is considered unacceptable in the industry standard. In general, variations in mechanical seed coat damage is a result of a series of factors including the genetics of the seeds, the seed moisture content, the environmental condition, and℗ the operation of harvest method. The end-use quality of organic dry beans can be enhanced using the identified genetic variability and improved processing methods.℗
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