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Three-point bending tests were conducted to determine the mechanical strength distributions of brown rice kernels. Three long-grain rice cultivars (Cypress, Drew, and XL6) were initially studied. Breaking force (the force required to break a brown rice kernel in three-point bending) was not significantly related to kernel width or length. However, there was a significant correlation between breaking force and kernel thickness; thicker kernels tended to have higher breaking forces. For all three cultivars, kernel-to-kernel breaking force distributions tended to be bimodal: one dominant peak existed around 30 N and a smaller peak around 15 N. The data showed that rice samples could have similar average kernel breaking forces, but their breaking force distributions were quite different. In turn, head rice yield was not related to the average breaking force of rice kernels in a sample; however, head rice yield was closely related to the percentage of strong kernels, defined as kernels that sustained a 20 N force in bending. Based on this apparent finding, the breaking force distributions and head rice yields for seven additional rice lots were measured. A linear relationship was observed between the sample head rice yield and the percentage of strong kernels in the sample.