The chip packets are made up of long polymer molecules that have been stretched so they're straight. When the plastic is heated, the molecules are bunched back up and thus you're left with a miniature version of your chip packet.
A lot of chip bags have a foil type lining. If your chip bag has this, it will start sparking immediately and may start a fire in your oven. If it is near the edge of the microwave, if may cause permanent damage to the oven.
Place your empty chip bag in the microwave. Heat it on high for NO LONGER than four seconds. If you heat it any longer, you could damage the microwave oven.
If you microwave your chips, they'll end up soggy and super-unappealing. The best way to reheat chips to make sure they stay lovely and crispy, is to do it in your oven.
A typical potato chip bag is made up of multiple layers of polymer materials: Biaxially Oriented Polypropylene (BOPP) on the inside, low-density polyethylene (LDPE) in the middle, another middle layer of BOPP, and an outer layer of Surlyn®, a thermoplastic resin.
Put the chip packet on top of a sheet of baking paper on a tray. Place a second sheet of baking paper over the top. Place the second tray on top to keep the chip packet smooth. Bake at 180°C for 10 minutes.
A typical potato chips bag is made up of multiple layers of polymer materials. The materials are Biaxially Oriented Polypropylene (BOPP) on the inside, low-density polyethene (LDPE) and BOPP in the middle, and an outer layer of Surlyn®, a thermoplastic resin.
The chip bag is not filled with air
Rather, they are filled with nitrogen, which is known as "slack fill." The nitrogen used to fill the bags before they are sealed is designed not only to create space for the chips, but also to keep them fresh and flavorful.
So, I like to jumpstart the cooking process with the microwave. Clean and poke your potatoes as described above. Then, wrap 'em in plastic wrap and pop it into a microwave for 5 minutes. (If you use this trick a lot, you can even invest in or make a reusable potato sack.)
Downing that full bag will result in increased blood levels of the chips' food components — approximately 90 grams of fat, 160 grams of carbohydrate and 1,500 mg of sodium.
You need to remove as much moisture as you can from them before you start reheating them, and Magda advises using a paper towel to pat them dry before reheating them. Then cook the chips on high heat in a pan or under the grill. Never try microwaving cold chips, Magda says.
It turns out, that empty space in your chip bag isn't just air — it's Nitrogen gas, which is meant to stop the chips from breaking in the package as well as expel air, which actually turns the chips stale. There's even a name for the emptiness — “functional slack-fill.”
Make stale chips great again! Microwaving stale chips with a cup of water for 30 seconds on high is supposed to make it crispy again.
So the next time you open a bag of potato chips and discover that the chips only fill about half of the package, you'll know that it's not just a marketing ploy to increase sales and that the extra air space in the package is there to protect the chips from being damaged during handling.
Thought that your potato chip bag was puffed up with air? The cushion actually is nitrogen gas. Chip manufacturers fill bags with this preservative gas to help keep chips fresh.
Check what they are cooked in, sunflower oil, 'high oleic' sunflower oil or olive oil are all good. If it just says vegetable oil it is usually palm oil which is less healthy. Crisps should be limited to 2 - 3 packets a week and less if following a low potassium diet.
Firstly, the extra space provides a cushioning effect that helps to protect the crisps from getting crushed during shipping and handling. Secondly, the extra space allows for air to be added to the bag, which helps to keep the crisps fresh.
Arsonists use bags of CRISPS to start fires because the fat is so flammable that it creates a potent and 'untraceable' accelerant.