Is Microwaved Food Dangerous to Health

Replies

• 

  CE Designer

  Also why does aluminum react so violently when place in the microwave
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  Kaustubh Katdare

  Yes, Microwave actually damages the food items. But no research would actually say that - because most of the research labs are actually funded by the companies that make microwave ovens 😀
  
  Here's what happens: Microwave generates frequencies to the tune of 2.5 GHz which can set the molecules of the substance into motion; resulting into heat. This heat makes the food look like it's cooked. But it's no brainer that at such level, the nutrients are destroyed as well! That's why there are several studies that show that regular microwave users do not receive all the nutrients they expect from the food.
  
  But at the same time, there are several pro-microwave studies too!
  
  I usually do not prefer microwaved stuff. It's always better and a safe bargain to eat raw food that nature has provided us.
• 

  Ramani Aswath

  I have a slightly different take on this.
  The water molecule is a dipole with a heavy oxygen ion in the centre and the two hydrogen ions located on arms at about 110 degree angle. This structure makes the molecule vibrate in an AC field. The frequency of th microwave oven is designed to match this frequency. E ach water molecule in tries to vibrate at this frequency. Since a lot of molecules are together they jostle each other like people in a crowd The viscous drag effect leads to generation of heat, which heats up the water (or food with water) and cooks. The laws of thermodynamics are not violated. The same amount of energy is required to bring to boil , say one litre, water in a microwave oven as on any other source of heat.
  The time to cook is also the same. There is no chemistry change irrespective of whether gas, radiant hob, electric hot plate or microwave is used for cooking. The main difference is that the heating takes place throughout the volume simultaneously in microwave while it is out side in - usually from the bottom with other heat sources.
  
  One less known fact about microwave cooking is that skin effect associated with AC applies in microwave cooking also. This is about 6 cm for microwave ovens for water. If a large volume of food is cooked it is better to stir it up occasionally to ensure uniform cooking.
  
  There is some confusion about radiolysis with microwave. Radiolysis happens when food is irradiated with Gamma rays or other hard radiation. Microwave is safe.
  
  On a personal level, we use a microwave pressure cooker. Quite a bit of our daily cooking is done on this. Since vegetables cook by their own water, no extra water is needed and so they cook faster, retain their natural colour and do not leach out nutrients into the water used for cooking which happens,if they are cooked in the normal manner. In normal boiling some of the flavanoids are lost by steam distillation. In microwave cooking you can feel the original flavour of vegetables like beans, carrots and broccoli.
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  Ramani Aswath

  CE Designer

  Also why does aluminum react so violently when place in the microwave

  It should not. What happens is that if aluminium foil is placed in the microwave the sharp edges lead to charge concentration and arcing. Since aluminium is a reactive metal it can catch fire. That is why aluminium powder is used so much in fireworks.
  If you place a large aluminium vessel with rounded edges nothing should happen.
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  CE Designer

  bioramani

  If you place a large aluminium vessel with rounded edges nothing should happen.

  I wouldn't risk trying this 😁
• 

  Ramani Aswath

  CE Designer

  I wouldn't risk trying this 😁

  I just did the experiment. 17 cm dia 5cm high aluminum wessel 0.8 mm thick with rounded lip in 2S aluminium was filled with about 200 ml water and put in the high wattage domestic microwave in our home. Setting max. power. Switched on, waited till water boiled and switched off. Remained right at the door to see if anything happens inside.
  Am typing this in person not my ghost.
• 

  Kaustubh Katdare

  Instead of performing the experiment myself, I turned to YouTube and discovered following -
  
  
  
  &
  
  
• 

  Ramani Aswath

  The_Big_K

  Instead of performing the experiment myself, I turned to YouTube and discovered following -

  That is the point. I have done that too. Much worse experiments in fact. Destroyed half a dozen microwave ovens, though as part of R&D. To study effects of foreseeable and unintentional misuse by users.
  
  I personally use some metal vessels in the microwave, when needed. Tall narrow vessels just reflect away the microwave much like the radar antennae and are useless.
• 

  Kaustubh Katdare

  In your experiment, you filled the vessel with water. I think that's why it didn't do much harm.
• 

  Ramani Aswath

  Repeated just now without water. Nothing happened. Vessel is cold, as it should be. Only issue is that it is inadvisable to run a microwave at full power for a long duration without any absorbing load. It can damage the magnetron and associated circuitry.
  
  The issue is that any metal (not just aluminium) with sharp edges will arc. There are some non vegetarian recipes for microwave where one has to shield some parts of the food with aluminium foil to prevent charring. As a vegetarian, my take on this is just what I have read.
• 

  Kaustubh Katdare

  Now that's an interesting observation.
  
  Back to the discussion : Do we have a solid evidence that the microwaves won't destroy the nutrients in food? All I see is mixed opinions about it on the Internet. Just wondering how can we check the protein content of peanut just out of microwave oven?
• 

  Ramani Aswath

  As far as I know it is hard radiation like gamma rays or nuclear radiation, which lead to radiolysis. I have done some studies on this earlier. Microwaves (200 GHz) are well below IR (200 THz). This cannot damage protein directly. If left too long in microwave food chars as it does on any heat source.
  I still believe that because of cooking through the whole volume cooking is faster and nutrients better preserved than in conventional cooking.
  
  #-Link-Snipped-#
  Abstract
  
  The effects of γ-irradiation treatments (2.5, 5 and 10 kGy) and microwaves generated from an oven at low and defrost power settings for 0.5, 1 and 2 min on the total proteins and protein patterns of beef liver immediately after treatment and during frozen storage (−18 °C) for different periods were studied. Chemical analyses indicated that the protein content of beef liver was reduced after exposure to γ-radiation or microwaves and also during frozen storage. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) was used to illustrate the changes in protein bands of different molecular weights and their percentages before and after exposure to gamma and microwave radiation. The main effect of γ-radiation on the protein patterns of beef liver was the disappearance of some high-molecular-weight protein bands and the development of other bands characterised by moderate and low molecular weights. This finding indicates the degradation of beef liver proteins by γ-irradiation. In contrast, microwave treatment caused an increase in the levels of high-molecular-weight protein bands with a concomitant decrease in low-molecular-weight protein bands. This phenomenon demonstrates the polymerisation of low-molecular-weight proteins under the influence of microwaves.
• 

  CE Designer

  Are we talking about cooking food or re-heating food? I do agree that at elevated temperatures vitamins and minerals get lost from the food.
  Food needs to be cooked in some way in order to aid in digestion and to kill bacteria and toxins and many other reasons.
  
  One vitamin that i know suffers major loss during cooking is Vitamin C. Foods rich in vitamin C such as Cabbage, Spinach, Broccoli and Green Peppers lose almost 50% of their vitamin C while cooking. This is due to the fact that heating increases the action the the oxidase enzyme (most active between 60-85 deg.cels.). Above 85 the rate of loss of the vitamin is less because the enzyme perishes at high temperatures. So i suggest cooking these foods quickly with the lid on and avoid reheating.
  Chopping and peeling also creates loss in vitamin C. The enzyme aforementioned becomes liberated and oxidation of the vitamin C occurs. So eat your slands soon after preparation. 😎
  
  Anyway the reason i had asked this question is because i thought i was being misled on the safety of microwave food. Radiation poisoning was the hazard identified to me. From what i read so far, if microwaves are the only source of radiation then i see no harm in this.
  I had once put an enamel bowl in the microwave and sparks were created on the rim of the bowl.
• 

  CE Designer

  CE Designer

  So eat your slands soon after preparation. 😎
  
  quote]

  Sorry I meant to say eat your salads 😲
  i couldn't edit
• 

  Ramani Aswath

  CE Designer

  I had once put an enamel bowl in the microwave and sparks were created on the rim of the bowl.

  Enmal bowls and plates usually have metallic thin film decorations. These arc under microwave.