Does microwaving eggs kill salmonella?

Question

If eggs are thoroughly washed and of course beaten before microwaving, and after the process I can find no liquid, is there a possibility that salmonella is still there, or does it die from high temperatures?

Asked by Septagram

Answer

Microwaves do not kill bacteria, heat kills bacteria. The higher the temperature, the faster those bacteria will die off.

"Instant death" for most bacteria (including salmonella) is about 160° F (71° C). You only need a few seconds at this temperature. The notoriously strict USDA recommends 160° F for egg dishes but is considerably more lax about whole eggs and just says to cook until firm. Very few eggs are contaminated in the whites or yolks, so the risk is very low.

Pasteurization begins around 57° C (135° F), so many bacteria are killed before the egg coagulates (at 63° C / 145° F), which is why the USDA is not very strict about it; if an egg by itself is "firm" then it's generally already been hot enough for long enough to ensure safety.

Unfortunately, microwaves tend to heat (a) quickly and (b) unevenly, so if you are concerned about food safety and insist on making eggs in the microwave (not recommended), be sure to use short bursts and stir several times, otherwise you might end up with a combination of uncooked and overcooked parts, which is bad for food safety and for general taste and texture.

Note that there is not only a possibility but actually a certainty that some salmonella is still there, assuming that there was any to begin with. Cooking is equivalent to pasteurization and that does not kill every single bacterium, nor is it meant to; it just kills about 99.9999% of them which makes the cooked item safe enough to consume.

Answered by Aaronut

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Is hot tap water safe for cooking?

Question

I'll typically bring hot water from the tap to the boil instead of waiting longer for cold water. This hot water comes from water heater with a large storage tank. Is this considered safe?

For example, are heater storage tanks known for festering nasties not killed by boiling? Is different piping used for hot water or different soldering on pipe fittings? Do hot pipes cooling down go through a temperature more conducive to bacteria growth?

Asked by jontyc

Answer

Unless your hot water tank is very close to your hot water tap, this is a very energy inefficient. As Jefromi notes it would be faster to boil water in a electric kettle first, and then pour it into the pan. Put the pan on the heat at the same time if you are really in a hurry

Hot water systems are normally hot enough (above 55°C, 130°F) to keep water borne nasties at bay, plus if you are on town supply water it will be chlorinated etc

Normally on the first few meters of hot water pipe are copper, then it switched to normal crimped plastic plumbing. This will vary depending on your local building codes

The rate at which pipes lose their heat would ensure it never sits in the danger area for long, not that I think this is a big issue for clean plain water

In general, modern copper pipes are not soldered, they are crimped using special hand tools

Old or non-renovated houses may still be 100% copper pipes that have been soldered. This poses no extra safety risks with just clean water in the pipes

Answered by TFD

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Washing Vegetables With And Storing Lemon Essential Oil?

Question

According to this article it is better to use lemon essential oil when washing vegetables. It is said to add prepared mixture to spray bottle but nothing about if it is possible to store spray bottle and under which temperature.

This is why i ask this question here. Maybe somebody knows?

Also, is it critical to store mixture in a clean new spray bottle or i can use cleaned spray bottle from windows cleaning detergent?

Thanks.

Answer

I don't see a point to doing this at all. The lemon oil may act as a mild surfactant in larger quantity. Use water and elbow-grease to clean your veggies -- you're primarily trying to remove dirt. Use of Scotch Brite-style scrubbing pads (so long as they're detergent-free) works nicely for heartier veggies like carrots and potatoes, and a vegetable brush or cloth for more delicate things.

If you're trying to kill germs, you may want to try soaking briefly in a VERY mild bleach solution. If you're trying to prevent browning via oxidation, particularly in cut vegetables, acidulated water should do the trick -- add some lemon juice or crushed vitamin C tablets to water and soak until needed.

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