How do rocks get into a bag of pinto beans?!
Answers:
Best Answer - Chosen by Voters
Not just pinto beans but many other types of dried beans need to be checked for rocks before cooking. They get in there occasionally because the machinery used to sort the stones out is 100% perfect.
You'll notice that the little rocks that are in any dry beans, not just pinto beans are the same size or smaller than the bean. This comes from sorting process, done by machinery and occasionally a small rock from the field where the beans were grown slips through. The bag usually has a warning about sorting the beans and then washing them well. Glad you found the rock before someone broke a tooth!
Because lazy beaners never do quality checks.
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