Make pressed cheese on a cold or cool day requires some general awareness so that you can modify some parts of your cheesemaking process when undertaking the pressing process
When cheese is pressed, the curd pieces knit together and are formed into the desired shape. This fusion of the thousands of pieces of curd particles relies on two processes: firstly the curd particles under pressure have to ‘flow’, which causes them to flatten and increase in surface area and then secondly these curd particles have to bond to each other. When cool or cold or dry curd particles are placed into a cheese hoop the contact area between the curd particles is lessened, basically the curd has become firmer and less resilient to the flow. The look of a finished cheese that is pressed while cold can be a rough and open texture, both internally or internally with obvious definitions of curd particles instead of a close-knit texture. Conversely warmed curd particles are more resilient and have a better level of distortion and knit together much better than colder curd. The best way to achieve correct pressing on a cool day is to have the room warm, temperatures above 25c are sufficient when you are filling your hoops. Then the filling of the hoop needs to be completed reasonably quickly, so when the curd is removed from the warm whey it does not have time to cool off or to dry off.
During the actual pressing stage, the hoop full of warm curd should not be allowed to cool, this is especially important for the first few hours after pressing has commenced. This warmth allows the fermentation process by the starter culture to continue which in turn assists syneresis, resulting in an increase in acidity and a decrease in the moisture content of the cheese. Both the moisture and acidity level will be very important attributes for the subsequent ripening process and the final quality of a matured pressed cheese. A cheese that has a higher than expected moisture level will probably have a higher level of protein degradation, higher acidity, possibly producing bitter compounds and a weaker pasty body.