2102.20.40.00 - Dried brewers' yeast, crude

This classification specifically covers dried brewers' yeast that is in a crude form. Brewers' yeast, derived from the brewing of beer, is typically processed to remove moisture, making it suitable for storage and further use. The term "crude" indicates that the yeast has not undergone extensive purification or processing beyond the drying stage, preserving its basic cellular structure and composition as a microorganism.

This category is distinguished from its sibling, 2102.20.20.00, which covers all other yeasts except dried brewers' yeast. Therefore, any dried yeast product that is not derived from the brewing process, or any form of brewers' yeast that is not dried and crude (e.g., live brewers' yeast or highly refined brewers' yeast derivatives), would not fall under this specific heading. The sibling category 2102.20.60.00 encompasses other dead single-cell microorganisms not otherwise specified.

As this is a leaf node in the HTS classification, there are no further subcategories under 2102.20.40.00. Therefore, classification within this heading relies on meeting the criteria of being dried, derived from brewers' yeast, and in a crude state. Examples of products falling here would include bulk dried yeast flakes or granules intended for use in food production, animal feed, or as a source of B vitamins, provided they are not further processed to a more refined state or are not live microorganisms.