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One of the greatest decisions of Sue Spence’s life certainly didn’t feel like it several years ago, as she stood askance in the home baking aisle of her local supermarket. She doesn’t remember exactly where she was; she doesn’t remember exactly how much she paid. But the 500g tin of active dry yeast produced by Lesaffre that she proudly sends a picture of is testament to her uncanny foresight. “It seemed stupid, but it didn’t cost much more than a small number of 7g packets,” explains Spence, who works as a software developer for a large tech firm.

Today, Spence is a miracle: a person in possession of yeast. As the coronavirus has taken hold and shut down our lives, we’ve taken to baking more. First the shortages were felt in flour, where you couldn’t get a bag of any type for love nor money. An extra 2.1 million people hit the supermarkets in search of flour during the four weeks before March 22, according to retail analysts Kantar, stripping the shelves of it. The websites of independent millers have crashed due to a surge in demand. One miller in rural Northumberland saw 200 orders – the usual number it received in a month – appear in its inbox in half an hour in late March.


And once the newly-minted home bakers of the country hoovered up all the flour, they came back for the yeast. March 2020 was already a record-breaking month according to Amber Trott, an analyst at Kantar. Total sales in fast-moving consumer goods, an industry term for items like packaged food and drinks, rose by 24 per cent. But yeast expanded at a rate the best boulanger would be proud of: 181 per cent.

But we weren’t stockpiling. It was simply a case of people who didn’t know their soda bread from their sourdough dabbling in baking for the first time. Three-quarters of a million more Brits bought yeast compared with the same period last year.

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This rush has caused major issues in the yeast production and packaging industry. Yeast is a carefully-produced product, but comes at great scale. Cofalec, a consortium of 33 factories across 22 European countries, produces more than a million tonnes of yeast a year, 30 per cent of which is exported outside Europe. While it doesn’t take time to make, the market is relatively centralised. Two major producers – Lallemand, based in the port town of Felixstowe, and AB Mauri, based on an industrial estate in Northampton – control the market. The overwhelming majority of yeast produced in the UK is fresh yeast, either in a cake or cream form. You take a batch of diluted molasses and seed it with the strain of yeast you want depending on its use and the climate in which most of it will be used. The yeast multiplies in giant vats, and becomes a concentrated slurry of yeast cells – the cream. Some modern industrial bakeries prefer their yeast in this form, while artisan commercial bakers prefer “cake” yeast, where the slurry is filtered and packed into supple blocks. Supermarkets hate fresh yeast because of its short shelf life and its difficulty in storage. So they want dry yeast.

“The production of dry yeast for the local market is very limited,” says Rob Wegman, a consultant who works with various yeast manufacturers around the world, including Lallemand. A small amount of cake yeast is extruded and combined with protective agents to make it dryable, before its moisture level is reduced to just a few percent of the product. Most of that yeast doesn’t stay in the UK: it’s exported to other countries with harsher climates, where the transport and storage of cake yeast would be even more difficult. Going from a single seeding to around 10,000 kilograms of dried yeast takes four days. The country’s yeast producers start the process every couple of hours, and haven’t stopped – at least not in Felixstowe, according to Wegman. AB Mauri and the UK Association of Manufacturers of Bakers’ Yeast, a trade body, declined to comment.


The hold-up, like with our flour supply issues, is further down the production chain. Bags weighing 800 kilograms are transported in a similar way to sand or gravel, but with aromatic-sealed inner liners. They are sent to packing companies who produce the small 7g or 11g sachets that home bakers know and love. "[Lallemand] used to make sachets, but it was a very small business," says Wegman. "Generally you go to manufacturers and packers and they will pack the instant dried yeast into sachets." The shelf life of the yeast is extended to several years by being vacuum sealed, or by inserting a small puff of nitrogen to prevent decay.

That’s where Wegman believes the issue is. “The yeast is being produced,” he’s quick to point out. “But all of a sudden the market is being hit by demand from household customers to bake their own bread. They want the sachets for one loaf. It’s simply insufficient packing capacity, and the lines dry out very quickly.”

Scarcity on the shelves has driven people to desperate measures. Searches for the phrase “yeast for bread” have increased more than 1,000 per cent in the last 30 days, according to digital tracking firm Glimpse. And enterprising sellers have sprung up, cutting up bulk packets of yeast into smaller sachets for home delivery through sites like eBay. Several sellers who appeared to be capitalising on the rarity of yeast in the current market, selling 25g packets of yeast for £3.39, a 900 per cent markup on supermarket yeast packet prices, did not respond to requests to speak for this story.

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“Call it supply and demand, or profiteering, some online sellers are asking ridiculous money for flour and dried yeast,” says Chris Young of the Real Bread Campaign. His organisation set up the #LockdownLoafers campaign, which collects and shares tips of where to buy ingredients, as well as recipes that use less yeast or none at all.


Yet this hasn't stopped people from buying yeast. More than 560 people have purchased the overpriced yeast from this seller on eBay, and internal metrics at the online auction site suggest that more than 500 people are viewing the listing every day. The seller is not the only one profiteering from a scarcity of yeast on supermarket shelves. Some people who have bought yeast from independent sellers have made payment, but haven’t received their items. Buyers are fighting back against price gouging. One Cornish baker haggled with an Amazon retailer charging three times over the odds, threatening to leave them with a bad review. The seller eventually sold it for the pre-pandemic price.

There are other options, of course. You can make a sourdough starter – or buy one, if you’re unable to mix flour and water together. Dried fruit also works, providing natural sugars to culture strains of yeast. If you’re desperate, soda bread can be made with buttermilk, flour and baking powder, and takes a fraction of the time. Or if you find some old yeast at the back of the cupboard that seems out of date, don’t throw it out – that stuff is gold dust.

“When I noticed the world going weird a week or so before the lockdown, I bought a fancy stand mixer since I thought I’d have time on my hands at home and might want to make baguettes or something,” says Spence. She doesn't know the expiry date of her yeast; she accidentally opened the 500g tin she bought years back from the bottom, rather than the top, removing the metal section where the date would have been embossed. However, she checked it, dropping a small amount into some warm water with sugar. It frothed and foamed. Until the packing lines can catch up to demand, she’ll have enough bread to keep her fed.

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