What is indicated by a strong fishy smell in fish products?

A strong fishy smell in fish products is an indicator that the fish may be spoiled. Fresh fish typically has a mild scent that is not overpowering. When fish begins to spoil, chemical changes occur, leading to the production of certain compounds like trimethylamine, which is responsible for the distinctly strong, unpleasant odor. This odor becomes more pronounced as the fish deteriorates, signaling that it is no longer safe to consume.

While freshness is characterized by a clean, ocean-like smell, and quality assurance involves ensuring that products meet safety and quality standards, the presence of a strong fishy smell directly contradicts these factors. Proper handling is crucial in maintaining fish quality and freshness, but once the fish shows a strong odor, it indicates that it has not been handled or stored properly, leading to spoilage. Therefore, the presence of a strong fishy smell unequivocally points to spoilage, making it the correct answer.