Are semi-frozen foods in grocery stores safe?

March 30, 2010 7:56 AM

Should I be concerned about frozen prepared foods that don't seem all that frozen in the grocery store?

I'm thinking specifically of frozen, already-cooked chicken nuggets, for example. Grocery stores often have them out in those open freezer tubs. Upon squeezing the package, the pieces are soft. When I find them in a closed freezer, the pieces are hard. Are the soft ones a real risk? Is it a bigger risk if they are raw?

posted by callmejay to food & drink (5 answers total)

Are the nuggets fully cooked and packaged as reheat to serve? I don't think you have much to worry about even if the nuggets aren't fully cooked, depending on the turnover of said nuggets in the open freezers.
posted by pmbuko at 8:11 AM on March 30, 2010

There's a strong likelihood that at least the quality will be impaired, if the frozen food is partially thawed. Are the packages at the bottom of the bin frozen harder than those at the top? Do you have the option of shopping at another store?
posted by Ery at 8:13 AM on March 30, 2010

I would absolutely avoid partially thawed foods, as I got food poisoning from partially thawed fish sticks once when I was 7. That said, I would not worry about veggies as if it comes from a good supplier it will just taste like crap, but chicken and fish tend to have a lot of pathogens that do start reproducing again once the food is thawed -- freezing does NOT kill E. coli and cooking often does not get rid of any toxins that were produced during spoilage. You really have no idea how long the food was in its thawed state or at what temperature, especially considering the transport distances and warehousing steps involved, and you can't trust that everyone did the right thing. Better safe than sorry.
posted by crapmatic at 9:42 AM on March 30, 2010

2 points on this

1) Safety - The temperature "danger zone" where microbial growth is greatest is between 40 degrees and 140 degrees Fahrenheit. If the food is thawed, very likely it has been inside this zone (above 40 degrees), thus increasing the possibility of getting some food born illness.

2) Quality - Ice crystals form jagged little points that break the cell walls of the food you are freezing. The faster the ice crystals form, the smaller the crystals, and the less damage. Commercial operations freeze food at -40 Fahrenheit to minimize the size of crystals (interesting side note: Clarence Birdseye figured this out while he was ice fishing and his catch froze, but thawed with a decent texture. He is now known as the father of the frozen food industry). Anyway, when a food is frozen, thawed, and refrozen, it increases the amount of damage. Especially when the refreezing is only done at zero F, when the ice crystals are larger. So I would still avoid the thawed foods because their quality is likely inferior.
posted by I am the Walrus at 1:23 PM on March 30, 2010

If you cook the nuggets or pieces to the temperature stated on the package (or if the package does not have a temperature stated to at least 165F...use a meat thermometer) then you are not in danger non spore forming food borne pathogens. As I am the Walrus stated, though, the ice crystal formation will cause quality defects that would likely deter me from eating the nuggets.
posted by catseatcheese at 3:54 PM on March 30, 2010