why freezing and defrosting food several times(eg 5 times) is unhealthy?

Question

assume is kept below 15 and above 100 degC . and the time taken to freeze and defrost is short (eg 1 hour).
I know tast will change due to intercellular ruptue but can it make you sick ?

Answer 1

The only relevant issue I can think of is growth of bacteria. From your example, bacteria had up to 5 hours to grow. For potato salad on a hot summer day, that's enough to get a harmful culture. Even if you subsequently kill all the bacteria, you can have enough toxins from when they were alive to cause significant harm.

The separate question is whether there's enough nutritional value left in the mush to be useful to the body.

Answer 2

It likely depends on the food and method of thawing and as you point out the time taken to thaw. Use of a microwave oven may not raise all portions to 100 degC., especially at the center because the microwaves are absorbed at the surface and may not penetrate thick slabs. If food is taken from the freezer compartment and thawed in the refrigerator compartment (taking more than the one hour you allow) bacteria are unlikely to grow. Each freeze cycle breaks down cell tissue (meats and vegetables) as you point out and the food resembles less and less the fresh food you bought. That does not necessarily make it unhealthy but it does not necessarily help it. Do growing ice crystals ruin proteans, etc.? Re-frozen ice cream often is filled with water-ice crystals removed from the ice cream and likely only affects its texture. Perhaps freezer burn is a bigger problem than re-freezing but one freeze-thaw cycle enhances the flavor of most freezable foods.

Answer 3

Not all pathogens are killed by temperatures at about 100 degC so you risk increasing the concentrations and therefore risk in proceeding in this way. Having said that if you can maintain a temperature of 115 deg c for a period of about an hour and a half most pathogens (please note I did say most) should be dead and the food may well be safe to eat, I wouldn't risk it though, Id send it to a microbiology lab for analysis! When needs must what you can eat will surprise you, rotten, maggot infected meat to name but one example, if boiled for a very very long time can be eaten, with some (but little) risk:

Answer 4

yes can make you very sck as you keep awaking bacteria and they mutiple then you freeze then they have chance to mutliple angain when it is defrosted again. words semonelia and ecoli come to mind.

Answer 5

freezing food doesn't necessarily stop the bacteria growing.. it justs slows it down.. each time you thaw it you promote the bacterial growth.

Answer 6

because every time it thaws out bacteria grows ,you should never do this,yes it can make you very sick,food should only be frozen and thawed once