Frozen sweet potato fries in an air fryer
From frozen — the short answer
190°C (374°F) for 18–20 min
- For
- 500g in total, From frozen
- In
- Multicooker with air fry
- Published for
- Ninja Foodi MAX Health Grill & Air Fryer AG551UK
- Preheat
- Yes, before the food goes in
- Part way
- shake the food at about 9 min
- Check
- Deep orange with dry, firm edges
- Safety
- Food cooked from frozen must reach the same core temperature as the same food cooked fresh — the frozen centre is the last thing to get there. Full rule below.
Eighteen to twenty minutes at 190°C — cooler and longer than ordinary frozen chips.
From frozen
Before anything else
From national food-safety authorities, not from us. These take precedence over any cooking time below.
Requirement — Food safety (microbiological)
Food cooked from frozen must reach the same core temperature as the same food cooked fresh — the frozen centre is the last thing to get there.
Target: 70°C in the thickest part.
How to tell, without a thermometer
- No ice or cold spot at the centre when the thickest piece is cut open
- Steaming hot throughout, tested in the middle rather than the edge
If it has not got there: Reduce the temperature by 10–20°C and give it longer. A lower set point lets the centre catch up before the surface passes the point of no return, and it is the single most useful adjustment for cooking from frozen.
Important: If the packaging says the product must be thawed before cooking, follow it. That instruction exists because the manufacturer has tested cooking it from frozen and it did not reach temperature reliably.
The quick answer
190°C (374°F) for 18–20 min
Published range for 500g, from the chart's frozen block.
- Assuming
- 500g in total, From frozen
- In
- Multicooker with air fry
- Published for
- Ninja Foodi MAX Health Grill & Air Fryer AG551UK
- Preheat
- Yes, before the food goes in
- Result
- Crisp outside, moist inside
Preparation
Frozen, with no oil and no preparation, as the row prints.
No oil needed.
While it cooks
At about 9–10 minutes: Shake the food
The chart tells the owner to shake or toss the food often and to check it frequently. It prints that beside the whole chart, not against this row, and gives no single point for it.
How to tell it is done
- Deep orange with dry, firm edges
- Not bending when lifted by one end
Where these figures came from — from frozen
- Applies to
- Specific to this model
- Why this rating
- A published row from the manufacturer's own guide for this appliance, held as the chart prints it: its amount, its preparation and its oil where it gives them, and nothing where it does not. Quantity is what makes a chart row checkable against the food in front of a reader, and this chart states one for almost every row.
- Last reviewed
- 2026-08-13
What this does not cover
- Published by the manufacturer for this appliance. It is evidence about this machine and is not general advice.
- This is a lidded cooking pot rather than a shallow drawer. Depth affects how much fits in one layer, and the quantity in the chart assumes the crisper basket.
Sources (1)
Ninja Foodi MAX Health Grill & Air Fryer AG551UK — Inspiration Guide and cooking charts (PDF)
SharkNinja Europe Limited — Manufacturer cooking chart (United Kingdom)
Relied on for: The temperature, time and quantity for frozen sweet potato fries.
States this directly
Passage read and verified
Retrieved 2026-08-13 from argos-support.co.uk
Retrieved from Argos's manual library for Argos product 735/0124, published alongside the instruction booklet as a second document.
What usually goes wrong
Limp, and darker than they should be. Sweet potato has little of the fine surface starch that crisps a chip, so most frozen versions are coated to compensate — and that coating is what crowding ruins first.
Running the appliance safely
The rules for the machine are the same whatever is in it: plug it straight into a wall socket, leave clear space round it, do not overfill it, do not leave it running unattended, and unplug it at black smoke or an electrical smell. They are set out once, each with its source and what to do if it has already happened, and not repeated on every food. Every rule for running an air fryer safely.
One of them is about this food and not the machine: Aim for a golden yellow colour or lighter on starchy foods such as chips and roast potatoes, rather than a darker brown.
Sweet potato in fast-moving hot air
Sweet potato carries far more sugar and far less of the fine surface starch that makes a chip crisp. The sugar caramelises and then burns at temperatures a regular chip is perfectly happy at, which is why the published whole-roast figure is 190°C where a jacket potato is 200°C. The flesh also holds more water and less structure, so wedges soften rather than developing the fluffy interior a floury potato gives. A sweet-potato chip that is genuinely crisp is difficult and usually involves a coating.
Where to go from here
The pages that answer the questions this one tends to raise.
- Using a thermometer, and where to put itThe times above are for a piece that is not the one you are holding. A probe measures yours, which is what the safety rule on this page asks for.
- How food actually gets crispyWhy patting it dry, spacing it out and a little oil are all the same instruction — so you can apply it when a page runs out.
- Cooking from frozenUsually cooler and longer than the same food fresh, and never worked out from the fresh figure.
- Why published timings differIf another chart says something else, this is usually why — and which one to believe.
Easily confused with
- Frozen chips — A different cooking problem with a different answer.
- Sweet potato wedges — A different cooking problem with a different answer.