Yellow stains on salmon can result from fat oxidation, natural fat separation, or spoilage. While oxidation alone may not always make salmon unsafe, bacterial spoilage certainly does. The safest approach is to rely on your senses — smell, sight, and touch — and discard the fish if anything seems wrong.

Salmon is nutritious and delicious, but it is also highly perishable. Treating it with care ensures you can enjoy it at its best, without putting your health at risk.