Walnuts in the Shell Grades and Standards

Grades of Walnuts in the Shell

  1. U.S. No. 1 consists of walnuts in shells which are dry, practically clean, bright and free from splits, injury by discoloration, and free from damage caused by broken shells, perforated shells, adhering hulls or other means. The kernels are well dried, free from decay, dark discoloration, rancidity, and free from damage caused by mold, shriveling, insects or other means. (See §51.2954.)

a. Kernel color shall be specified in connection with this grade in terms of “extra light,” “light,” “light amber,” or “amber” from the USDA Walnut Color Chart or in terms of “red” color. The color classifications in the USDA Walnut Color Chart shall not apply to “red” color. Furthermore, “red” color shall not be mixed with “extra light,” “light,” “light amber,” or “amber” colors. When kernel color is based on the color classifications from the USDA Walnut Color Chart, at least 70 percent, by count, of the walnuts have kernels which are not darker than “light amber,” and which are free from grade defects: Provided, That at least four-sevenths of the above amount, or 40 percent of the walnuts have kernels which are not darker than “light.” Higher percentages of nuts with kernels not darker than “light amber” which are free from grade defects and/or higher percentages with kernels not darker than “light” which are free from grade defects, may be specified in accordance with the facts. (See §51.2954.)

b. Size shall be specified in connection with the grade. (See §51.2952.)

  1. U.S. No. 2 consists of walnuts in shells which are dry, practically clean and free from splits, and free from damage caused by broken shells, perforated shells, adhering hulls, discoloration or other means. The kernels are well dried, free from decay, dark discoloration, rancidity, and free from damage caused by mold, shriveling, insects or other means. (See §51.2954.)

a. Kernel color shall be specified in connection with this grade in terms of “extra light,” “light,” “light amber,” or “amber” from the USDA Walnut Color Chart or in terms of “red” color. The color classifications in the USDA Walnut Color Chart shall not apply to “red” color. Furthermore, “red” color shall not be mixed with “extra light,” “light,” “light amber,” or “amber” colors. When kernel color is based on the color classifications from the USDA Walnut Color Chart, at least 60 percent, by count, of the walnuts have kernels which are not darker than “light amber,” and which are free from grade defects. Higher percentages of nuts with kernels not darker than “light amber” which are free from grade defects, and/or percentages with kernels not darker than “light” which are free from grade defects, may be specified in accordance with the facts. (See §51.2954.)

b. Size shall be specified in connection with the grade. (See §51.2952.) 

  1. U.S. No. 3 consists of walnuts in shells which are dry, fairly clean, free from splits, and free from damage caused by broken shells, and free from serious damage caused by discoloration, perforated shells, adhering hulls or other means. The kernels are well dried, free from decay, dark discoloration, rancidity, and free from damage caused by mold, shriveling, insects or other means. (See §51.2954.)

a. Kernel color may be specified in connection with this grade in terms of “light amber” or “light” from the USDA Walnut Color Chart or in terms of “red” color. The color classifications in the USDA Walnut Color Chart shall not apply to “red” color. Furthermore, “red” color shall not be mixed with “extra light,” “light,” “light amber,” or “amber” colors. When kernel color is based on the color classifications from the USDA Walnut Color Chart, there is no requirement in this grade for the percentage of walnuts having kernels which are “light amber” or “light.” However, the percentage, by count, of nuts with kernels not darker than “light amber” which are free from grade defects and/or the percentage with kernels not darker than “light” which are free from grade defects, may be specified in accordance with the facts. (See §51.2954.)

b. Size shall be specified in connection with the grade. (See §51.2952.)

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