Worth the wheat
As wheat prices hurtle skywards, many ingredients firms might be tempted to avoid it at all costs, but ingredients giant Cargill has thrown caution to the wind with a £75M newly converted wheat mill.
The company had previously used corn as its raw material for glucose, but is confident that wheat is more promising option. "We've built a plant that is capable of servicing customers for the next 15-20 years without significant investment," says Cargill's general manager Martin Douglas.
Sourcing 90% of wheat from the surrounding areas of Yorkshire and Lincolnshire, the Manchester-based plant takes deliveries from up to 100 28t trucks a day. "Farmers are getting a good deal as we're paying more than they'd get on the world market," says Douglas. "It's also good for manufacturers as local produce has government and retail support. This demonstrates that we can do the same sort of thing in the processed sector as is happening in the fresh sector."
Once the wheat has been cleaned, bran is split from the grain using sifters - huge metal boxes which vibrate violently as their contents filter through 20 decks. While the bran is used in wet and dry animal feed, the grain is milled into flour, mixed into a dough and sent into a decanting process so that it can be separated into different starch grades based on granule sizes. Larger granules are sent to the glucose refinery to be made into glucose syrup for the food industry.
Meanwhile, smaller granules are either classed as fermentables, which are sent for ethanol production; or vital wheat gluten, which is dried and supplied to the bakery and aquaculture industries.
It is the latter product that has proved to be a serious sticking point in the factory's initial start up. "It's like chewing gum!" says plant manager Neil Barker. "Trying to dry 8t of the stuff has lost me many hours of sleep!" Douglas agrees: "Vital wheat gluten starts as a liquid, but as it dries, it sticks to everything." He explains: "To begin with, the vital wheat gluten process was a bottleneck. Superficially, it's a less high profile part of production, but without it, everything else stops working. Through Christmas and New Year, we had three or four weeks in which we couldn't get it to dry efficiently and ultimately, we had to change the specification and alter the design of our machines."
Nevertheless, the company is making good progress. "We've solved the macro problems and we're running at 80% capacity," says Douglas. "You can manage these big flour mills through science, engineering and mathematics to get them to run at 80%. The next 20% is about getting touchy feely and familiar with the system and that's the skill of the miller.
"Our guys are learning those skills and every day they're getting more out of what we've got. It's that micro understanding - having the finger on the pulse of the plant, rather than what the instrumentation tells you - that will get you there in the end."
