The coronavirus lockdown has seen many panicked shoppers head to the supermarket in a desperate rush to stock up on supplies, resulting in some shops running low on basic items.
And as well as shortages on toilet roll, pasta and canned goods, a new nationwide interest in baking has resulted in a scarcity of flour and other cake ingredients too.
So why has flour in particular become so elusive - and where can you still buy it?
Why is there no flour?
A rise in the amount of people who are home baking appears to be contributing to the shortage of flour in supermarkets, although a lack of supply is not the problem.
The issue is not being able to mill enough flour, but rather the mills don’t have enough capacity to pack enough of it into bags for supermarkets.
The National Association of British and Irish Millers (NABIM) said the industry is “working round the clock” seven days a week in an effort to double production, although it is still struggling to meet demand.
The UK produces around 90,000 tonnes of standard flour each week, but only 12 of the 50 mills in the country are geared towards retail.
Despite keeping the mills running for 24 hours a day, seven days a week, the demand is still too high.
Why is demand for flour so high?
Since the coronavirus outbreak hit the UK, shoppers have been buying more flour than usual, resulting in existing stocks being depleted more quickly.
Only around four per cent of flour in the UK is sold through shops and supermarkets, according to NABIM, with the majority of flour produced in bulk and then delivered in tankers, or bags, of more than 16kg to bakeries and food manufacturers.
Alex Waugh, director of NABIM, said packing lines are now running at maximum capacity, but this is still only producing enough for 15 per cent of households to buy a bag of flour per week.
And existing packing lines cannot easily be adapted to produce smaller retail bags, as the industry is geared towards distributing at scale.
Mr Waugh told the i: “There isn't a problem with production. It's just that most goes to big food brands and bakeries.
“Bags are usually 25kg or 16kg. To pack for consumer retail requires a different line, and people don't usually buy so much."
"We have plenty of flour, there's a lot of it about. It's just a question of scale.
“Normally people buy 2m bags of flour per week. That's doubled to 4m, and we're at the absolute max. Everyone's working overtime."
How much flour should I buy?
NABIM is considering the possibility of shops selling larger bags, due to being better equipped to produce flour in bulk, but Mr Waugh said that this could still be some time off yet.
For now, shoppers will simply have to wait for stock levels to be replenished and for demand to fall.
Flour is still being supplied to supermarkets across the UK as normal for shoppers to buy, and Mr Waugh advises that consumers be mindful of how much they purchase until demand lessens.
He said: “The public [must] only buy flour if they need to. If you're not using flour, don't buy more - we're not going to run out.
“It's better to avoid stockpiling so that others have the opportunity to bake."
Where can I buy some?
If you are struggling to track down any flour in the supermarkets, there are some retailers online that still have some stock.
Healthy Supplies has a wide range of options, including wheat, corn, rice, buckwheat and pasta flour.
Buy Wholefoods Online also has stock available, with bread flour, gluten free flour, nut and specialist flour all on offer.