Certification & Core Plus Development Guides. The Guides were initially implemented on October 1, 2007. While changes to the certification standards are normally implemented on October 1, of any given year, other aspects of the guide, in particular the Core Plus component may be modified throughout the year.
Time. Fresh fish will only last in the refrigerator for one or two days, and shellfish will last up to three days. For longer periods of storage, you must freeze the fish or it will spoil. However, do not refreeze the fish once you have thawed it.
How Long Can You Keep Frozen Fish According to the USDA, frozen foods will keep indefinitely if stored in an airtight package at a constant temperature at or below zero degrees Fahrenheit. Freezing fish does not decrease its nutritional value. Freezer burn may dry the fish out in spots, but it is still safe to eat. Long-Term Freezing Affects Quality Storing fish for an extended period of time in the freezer affects its quality. Raw fish remains at a higher quality after freezing than cooked meats, because cooking depletes moisture. You should only be concerned about frozen fish if the package has ripped or opened, exposing it to air. If it has gone rancid, it will have a strong fishy smell.