1515.29.00.20 - Once-refined (subjected to alkalai or caustic wash, but not bleached or deodorized)

This HTS classification covers once-refined corn (maize) oil and its fractions. "Once-refined" in this context specifically denotes oil that has undergone an alkali or caustic wash treatment. This process is employed to remove impurities like free fatty acids, phospholipids, and gums, thereby improving the oil's stability and appearance. However, it is crucial to note that for this specific subcategory, the oil has *not* been further processed through bleaching or deodorization.

The key distinction for this category, 1515.29.00.20, lies in the limited refinement process. Its sibling category, 1515.29.00.40, covers "Other" corn oil fractions that are fully refined, meaning they have also been subjected to washing, bleaching, and deodorizing. Bleaching removes color pigments, while deodorization eliminates undesirable odors and flavors. Therefore, the difference hinges on the presence or absence of these subsequent refining steps after the initial alkali or caustic wash.

As a leaf node in the HTS classification database, this category does not have further subcategories. The classification concludes at this level based on the described refinement status. Examples of products falling here would include corn oil that has been washed to remove impurities but retains its natural color and odor.