Final answer:
Dihydroxyacetone is not a fermentation product as it is an intermediate in glycolysis, whereas ethanol, lactate, and propionate are products of different fermentation pathways.
Step-by-step explanation:
The product that is not a fermentation product is dihydroxyacetone. Fermentation is an anaerobic process that occurs when oxygen is not present, and it allows for the continuation of glycolysis by ensuring an adequate supply of NAD+. Some fermentation methods such as lactic acid fermentation can occur in animal skeletal muscles, and alcohol fermentation occurs in yeast and some bacteria.
Of the options listed (ethanol, lactate, propionate, dihydroxyacetone, butyrate), the first three are indeed products of different fermentation pathways. Ethanol is produced by alcohol fermentation, lactate by lactic acid fermentation, and propionate by propionic fermentation.
Dihydroxyacetone, however, is an intermediate in glycolysis and not a direct product of fermentation. Butyrate is another compound produced in certain types of fermentation. Therefore, dihydroxyacetone is not a fermentation product.