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A variety of pyridine and pyrazine derived compounds are formed in malt (and other foods) during the malting process as a result of Maillard reactions and have been found to be major contributors to the "malty" flavor of beer. Examples of these compounds include 2-acetylpyridine, 3-acetylpyridine, methylpyrazine, forms of dimethylpyrazine, and trimethlpyrazine. These compounds have a range of flavor descriptors such as creamy, cardboard, grainy, and burnt sugar. For example, 2-acetylpyridine (2AP), also known as 1-pyridin-2-ylethanone, is described as having a malty-biscuity, corn-chip, corn tortilla, or popcorn flavor. These compounds (in particular 2AP) can easily be confused with forms of THP, but they are not the same as the varieties of THP explained above <ref name="Adams_2005" /><ref>[https://en.wikipedia.org/wiki/2-Acetylpyridine 2-Acetylpyridine. Wikipedia. Retrieved 09/04/2018.]</ref><ref>[http://www.thegoodscentscompany.com/data/rw1012221.html 1-pyridin-2-ylethanone. The Good Scents Company website. Retrieved 09/04/2018.]</ref><ref>[https://www.aroxa.com/beer/beer-flavour-standard/2-acetyl-pyridine/ 2-acetyl pyridine. Aroxa website. Retrieved 09/04/2018.]</ref><ref>[https://onlinelibrary.wiley.com/doi/pdf/10.1002/jsfa.2740280218 Basic compounds contributing to beer flavour. Richard J. Harding, Harry E. Nursten, John J. Wren. 1977. DOI: https://doi.org/10.1002/jsfa.2740280218].</ref>. Another form is 2-formyl-1,4,5,6-tetrahydropyridine (FTHP), however, its presence in fermented beverages has not been well studied and it is less stable than other forms of THP, making it difficult to study <ref name="Martusevice_2024">[https://pubs.acs.org/doi/abs/10.1021/acs.jafc.3c09776# A Review of N-Heterocycles: Mousy Off-Flavor in Sour Beer. Paulina Martusevice, Xueqi Li, Matt J. Hengel, Selina C. Wang, and Glen P. Fox. Journal of Agricultural and Food Chemistry 2024 72 (14), 7618-7628. DOI: 10.1021/acs.jafc.3c09776.]</ref>. One indicator that a particular flavor might be THP instead of one of these malt-derived flavors is that THP is mostly detected on the aftertaste after swallowing, whereas these compounds are often detected during the swallow (although they can sometimes also be detected during the aftertaste).