Air Fryer Mistakes to Avoid: 12 Things That Ruin the Result, and What Not to Put in It
Can you put foil in an air fryer? Yes, in small pieces that are weighed down by food and kept away from the heating element. It is the most searched question about air fryers, and the answer is a good example of how most rules work: a few simple limits make nearly everything safe, and breaking them causes smoke, poor cooking or damage.
This guide lists twelve mistakes that spoil results, then covers what you can and cannot put in the basket. Always read your manual first, because it takes priority over general advice.
Twelve mistakes that ruin the result
- Overfilling the basket. Food piled up steams instead of crisping. Cook in a single layer and do batches, as the beginner's guide explains.
- Skipping the preheat. About 3 minutes at the cooking temperature gives frozen food and pastry a strong start.
- Preheating with loose paper or foil. The fan can lift it into the element. Preheat empty, then add paper with food on top.
- Never shaking or turning. Chips, sprouts and sausages brown unevenly. Shake or turn halfway.
- Blocking the airflow. Cover only part of the base and leave a gap round the machine, at least 10 cm at the back and top.
- Using too much oil. One teaspoon is plenty. Heavy oil smokes and makes food greasy.
- Cooking wet food. Pat meat, fish and potatoes dry. Soak chips in water first, then dry them thoroughly.
- Trusting the clock for meat. Use a probe thermometer. Poultry, sausages and minced meat need 75 °C in the centre, and pork cuts 70 °C.
- Using the wrong temperature. Thick items need a lower heat for the middle to catch up. Large jacket potatoes drop to 190 °C, for example.
- Putting in loose batter. Wet mixtures run through the holes. Use a tin, mould or silicone case.
- Using unsuitable containers. See the table below.
- Not cleaning it. Old grease smokes and can taint food. Wipe the basket after every use, following the how to clean an air fryer guide.
What can you put in an air fryer?
| Item | Safe? | How to use it |
|---|---|---|
| Foil | Yes, in small amounts | Held down by food, below the rim, away from the element |
| Foil tray | Yes, if it fits | Leave a gap on every side |
| Baking paper | Yes | Perforated, with food on top |
| Greaseproof paper | Check the pack | Only if rated for oven temperatures |
| Metal tin or dish | Yes, if oven-safe | Must fit with air space around it |
| Glass or Pyrex | Only if heat-resistant | Check the manual and avoid sudden temperature changes |
| Ceramic dish | Yes, if oven-safe | Same rules as glass |
| Plastic | No | Unless the label gives a temperature above 200 °C |
| Cardboard | No | Never, including pizza boxes |
| Wooden skewers | Yes, with care | Soak first and keep the ends clear |
| Silicone | Yes | Heat-safe to 200 °C |
Foil, trays and baking paper
Foil, whether called tin foil, aluminium foil or kitchen foil, works well for wrapping fish or making a shallow tray. Do not line the whole basket, because it blocks the air. Avoid acidic food such as tomatoes and lemon juice on foil, as acid can react with the metal. Foil on jacket potatoes makes the skin soft, so leave them bare if you want crisp skin.
Baking paper is safe as long as it stays under the food. The baking paper in the air fryer guide explains cutting and fitting. Silicone liners suit sticky food.
Glass, Pyrex and metal
Heat-resistant glass and ceramic dishes work if the manufacturer says so. They need enough room around them for air to move, and the food inside will cook more slowly than in the open basket. Never put a hot dish onto a cold worktop or add cold water to a hot dish, as sudden changes can crack glass. Metal tins are fine if oven-safe and small enough to fit. Never use metal in a microwave, but an air fryer is not a microwave, so metal is allowed.
Some air fryers have a glass bowl or window. Clean these gently and do not use scourers that would scratch the glass.
Oil, water and liquids
You can use a little oil, brushed or from a pump spray. Aerosol cooking sprays can damage non-stick coatings, so check the manual. Do not pour water into the basket or the main unit. Some manuals allow a small splash of water in the drawer under the basket to reduce smoke from very fatty foods, but only follow this if yours does.
Frozen food, sausages and dishwashers
Frozen sausages can go in the air fryer straight from the freezer: 180 °C for 16–18 minutes. Check the basket and drawer for dishwasher markings before putting them in a dishwasher, since some are safe and some are not.
Questions and answers
Can you put foil in an air fryer with any food?
You can, but only when it suits the food. Use it for wrapping and shaping, and keep it off the element and away from acidic food.
Can you put baking paper in an air fryer?
Yes, with food on top and never during preheating. Perforated paper allows better airflow.
Can you put a glass bowl or Pyrex dish in an air fryer?
Only if it is heat-resistant and listed as safe by the maker. It must fit with air space around it and should not go through sharp temperature changes.
Can you put plastic in an air fryer?
No, unless the item is clearly marked as safe above 200 °C. Most plastic containers will warp or melt.
Can you put the basket in the dishwasher?
Check the manual or part markings. Hand washing is gentler on the coating even where a dishwasher is allowed.
