Oysters are a perishable food, and the way they are preserved has a great impact on their freshness and safety. Here are a few ways to preserve oysters:

1. Refrigerate: Place purchased oysters in a large bowl, add ice water (not cold water) until the oysters are covered, and store in the refrigerator. Oysters chilled in this way will keep for 3-4 days.

2. Freezing method: Pick out the meat of the oysters, clean up the unclean parts, if there are any unclean parts, you can use water to wash off the sand and mud and impurities first, dry them, then put them into a ziploc bag and put them into the refrigerator freezer to freeze. Oysters frozen and preserved in this way can be preserved for 3 months, but thawed and cleaned before consumption.

3. Soaking: Soak the oysters in salt water overnight, rinse well, and store in a ziplock bag. This method will keep the oysters fresh, but only for one night, so if you don't eat them in time, they still need to be kept refrigerated.

Notes:

1. Do not mix fresh oysters with other foods to avoid spreading bacteria.

2. During the preservation of oysters, if you find any expiration date, deterioration, odor, discoloration, etc., you should throw them away immediately.

3. Before consuming oysters, they should be heated until they are cooked through, which can kill any bacteria that may be present in them to avoid food poisoning.