Can seaweed be eaten after being stored for three to four years

Seaweed stored for three to four years is usually not recommended for consumption. The shelf life of dried seaweed is generally 12-18 months, and long-term storage may pose health risks due to moisture, mold, or nutrient loss. When dried seaweed is stored under sealed and dark conditions, a moisture content of less than 10% can inhibit microbial growth, but it is susceptible to environmental humidity after exceeding its shelf life. The protein and free amino acids in seaweed will gradually degrade with prolonged storage time, and the content of umami substances such as glutamic acid will significantly decrease. If the packaging is damaged or the storage environment humidity exceeds 60%, it may breed mold and produce harmful substances such as aflatoxin. High temperature and high humidity environments will accelerate this process. Seaweed that is vacuum packaged and stored at a constant temperature and humidity under special circumstances, tested by a professional organization to be free of mold and meet all required indicators, or can be consumed. However, it is difficult to achieve industrial grade sealing standards for household storage, and there may be invisible mycelium proliferation on the surface of seaweed. The 2012 National Food Safety Standards clearly stipulate the limit standards for mold in dried algae products, and expired seaweed cannot completely destroy certain fungal toxins even when cooked at high temperatures.

It is recommended to choose small packages of seaweed when purchasing and consume them within the shelf life. After opening, they should be sealed and refrigerated. If seaweed is found to have mold spots, a crackling smell, or a sticky texture, it should be discarded immediately. Seaweed can be stored in a desiccant jar in daily life to avoid mixing with dried seafood and prevent spoilage. Before cooking, observe whether the color is uniform and smell for the fragrance of seaweed. Be alert to the turbidity of the soup after brewing inferior seaweed.