One of the most important issues in cheese making is the reduction of fat and cheese fines in whey. While many modern cheese plants recover the lost fat and fines, it is more beneficial to achieve the highest possible yield of fat and protein during the process to optimise production costs.
As a result, Invensys APV has upgraded its Curdmaster agitator line. The company believes that this will allow manufacturers to improve their cheese making capabilities.
For more than 10 years, APV has developed the "double-O" Curdmaster cheese tank. The agitators are the most recent parts to have been redesigned.
APV believes that the way the knives and shovels are assembled is critical to the performance of the CurdMaster. After initial tests, the number of knives as well as the length of each knife were adjusted.
The knives were then moved to another position on the frame, which was also redesigned to support the new agitator design and make the CurdMaster more flexible for the production of different cheese types, including cheeses made from milk with a high protein content. These modifications resulted in more uniform-sized cheese curds, the size of which could be adjusted, depending on the type of cheese.
Finally, a clear knife cut of the curd was achieved, reducing the cheese fines and the fat in the whey.
To support this improvement, two shovels were installed on each stirring frame. The size and shape of the shovels were also modified to optimise the agitation function, resulting in improved lifting and buoyancy of the curd in the whey. At the same time, it proved possible to reduce the speed of the agitator, minimising the mechanical impact on the cheese curd.
The new agitator design has been successfully tested by three manufacturers of different types of cheeses, ranging from semi-hard Danish cheese types to Cheddar and other types of hard cheeses.
One of these manufacturers immediately ordered two new cheese tanks and the rebuild of three existing tanks, since the test and commercial runs showed a reduction of the amount of fat and cheese fines in the whey of up to 35 per cent - an impressive result in terms of cheese yield.
Existing CurdMasters can easily be retrofitted with the new agitator to deliver the same benefits as a new CurdMaster. Existing recipes can be amended to ensure that the composition of the final cheese is the required specification.