Sunday batch of chicken breasts at 148°F, ice bath, fridge, labelled, feeling very organised. Then Monday lunchtime I'm standing in the office kitchen with a bag of cold chicken and a microwave and I realise every reheating guide on this site assumes I have a circulator with me. I do not. The office has a microwave, a kettle, and a sink that is best not discussed.
So the actual questions. Is it SAFE to microwave it, given it was cooked at a lower temperature than the usual 165 number? Is it going to go rubbery and dry and undo the whole point? Do I microwave it in the bag or take it out first (the bag says vacuum sealer bag, nothing about microwaves)? And how long does the bag sit fine in my desk drawer before lunch, because the office fridge is a lawless place and things go missing. Sorry, that's four questions. It's been a long Monday and the chicken is still cold.
Out of the bag, always. Sealed vacuum bag in a microwave is a little steam balloon waiting to happen and mine split down the seam. Slice it, plate, cover, short bursts.
I've been doing this for two years of packed lunches and the trick is to stop thinking of it as reheating a chicken breast and think of it as reheating slices. A whole breast in a microwave gets hot at the thin end and stays cold in the middle, so you keep going and the thin end turns to rubber. Sliced into 1 cm pieces, laid out flat, covered, medium power in 45 second goes with a stir in between, it's hot through in about two minutes and really not that far off fresh. Bit of the bag juice spooned over it before it goes in makes a real difference too.
The desk drawer, no. Cold chain until lunch. I use a small insulated bag with an ice block and it's still properly cold at one.
Yes, you can microwave it, and from a safety point of view it is fine, with two conditions: the chicken was pasteurised in the original cook, and it has stayed cold since. The circulator gives you a ceiling on doneness, which is a texture advantage; it is not what makes reheated food safe. Safety was settled on Sunday when the breast was held at 148°F (64°C) for long enough for its thickness, and it is preserved by the cold chain, not by the reheating method. The 165°F (74°C) figure people quote is a standard for cooking raw poultry with methods that cannot hold a temperature, and it is a good default for anyone not working from published tables; it does not need to be re-hit on a reheat of something already pasteurised and properly chilled. For reheating, the usual advice for leftovers of any kind is to get them steaming hot right through, and that is what I would aim for in a microwave: hot throughout, no cold centre.
On texture, the microwave has no ceiling, so it will happily push a 148°F breast past 160°F (71°C) in the thick part while you wait for the thin end. Garagegriller's method is exactly right and is what most kitchens do with any cook-chill protein when there is no bath: portion or slice it, lay it flat, cover it so it steams rather than dries, reduce the power, and heat in short bursts with a stand in between so the heat evens out. A little of the bag liquid or a spoon of stock over the top before it goes in helps. Two to three minutes for a sliced breast is a reasonable expectation; if it takes much longer you have too much on the plate. Out of the bag, always: a sealed bag traps steam, and vacuum bags are rated for the bath, not for the pressure and hot spots of a microwave unless they say so.
The drawer is the one part I would not do. Cooked chicken between 40 and 140°F (4 to 60°C) is in the range where whatever survived, or landed on it after opening, can multiply, and a few hours in a warm office is a real window. Cold bag, ice block, or the fridge, and eat it within the same three to four day plan you would use at home, as set out in the meal prep guide. If anyone eating it is pregnant, elderly, or has a weakened immune system, or if you are doing this at any scale beyond your own lunch, follow the food-safety rules that apply to your own situation rather than a forum reply, and the reheating guide covers the bath version for when you are at home.
Kettle method as a middle ground, if the microwave offends you. Slice the chicken, put it in a bowl, pour just-boiled water over, cover with a plate, wait 5 or 6 minutes, drain. Not as controlled as a bath but it's gentle and it's never once gone rubbery on me. Tea afterwards, obviously.
Week and a bit of trying all of this. Sliced, covered, medium power, 45 seconds twice with a stir, splash of bag juice: genuinely good, colleague asked what I'd done differently. Tried Mike's kettle bowl one day when the microwave queue was silly and that was fine too, maybe even better on texture, just more faff. Insulated bag with an ice block replaced the drawer. Nobody's stolen it yet, though I suspect that's because it's chicken and not somebody's birthday cake.
This one's closed: 60 days went by with no new replies. Cook times age fine, but safety answers deserve a fresh look, so check the current charts or ask a qualified professional rather than trusting a dusty thread.
