Reheating frozen food (stew)

jodyanne

Can anyone tell me whether it's safe to heat frozen food (like stew) directly in the microwave?

If I've frozen some extra portions of stew, I will always defrost them for 24 hours in the fridge before heating them up for eating (that's what the mammy always told me to do). My partner, however, insists that it's ok to put the frozen stew straight into the microwave from the freezer. Anyone know which one is correct?

P. Breathnach

I have done it, and live to tell the tale. Give it plenty of time on the defrost setting, and stir it a few times: microwave ovens generally do not heat things evenly.

I think it is better to use your method but, if you are hungry and it's the only food readily available, go for it.

bonkey

jodyanne wrote: »

Can anyone tell me whether it's safe to heat frozen food (like stew) directly in the microwave?

Yes. Its fine.

If I've frozen some extra portions of stew, I will always defrost them for 24 hours in the fridge before heating them up for eating (that's what the mammy always told me to do).

The mammy is probably basing her reasoning on pre-microwave recommendations, particularly to do with things like frozen poultry.

Back in the day when microwaves were things for sciency-types to study, you were recommended to let frozen raw food thaw before cooking so that it would cook through, rather than risk having a perfect-looking outside and underdone inside. This was particularly important with the good ol' frozen turkey and chicken.

When it came to the likes of pre-cooked food, it was (to my knowledge) still a preferred approach, mostly because cooking/reheating from frozen will be uneven, where the stuff on the outside thaws and cooks longest, while the rest thaws progressively later and cooks less.

From a safety point of view, there is no health risk from reheating-from-frozen, with or without a microwave. The only real "risk" is that you'll get hot- or cold-spots in your reheated stew (neither are pleasant). With a microwave, this is probably even less of an issue, due to the way it cooks.


My partner, however, insists that it's ok to put the frozen stew straight into the microwave from the freezer. Anyone know which one is correct?[/QUOTE]

rubadub

Substances have different "loss factors", basically their ability to absorb microwaves. Also stuff at different temperatures has different loss factors.

Water absorbs microwaves very well, ice does not! If you put a frozen glass of water and normal glass of water in the microwave it will get hot while the ice glass is barely effected. Once a little drop of water does defrost then the microwaves start piling into it. It heats up really quick and its own heat defrosts the frozen bits around it (rather than the microwaves, it just conducts heat). This defrosted spot then absorbs microwaves again and you end up with a little heat spot, it is like putting a tiny bit of water in a kettle, all the power goes into it and it heats really fast.

So if you microwave a frozen burger you can see brown cooked bits, that can dry out they are cooked so much, while the rest is frozen. Happens with all meat but with burgers you notice the colour a lot more. The first places to go are usually where you touched the item, your fingers defrosting it slightly.

Solution?- simple! just rinse your item under a warm tap before microwaving. It is now coated in a layer of water which will absorb the microwaves and inturn defrost the rest by conduction, once defrosted it absorbs microwaves well. Just keep stirring stuff like stew so it all melts evenly enough.

Loopy

I do it all the time...:)