I was discussing how to make a freezer slow freeze food with somebody and asked them a question, they then gave me the below reply however I don't understand it properly. Can somebody please explain what he is sayting.
Question: I believe you said the rate at which the meat will freeze will depend upon the 'size and load' of the freezer. I thought the temperature of the freezer alone e.g. -5c would be enough to ensure slow freezing regardless of size and load of freezer. Can you explain if this is not the case and if so how, technically speaking, the freezers size and load affect the rate of freezing? I note you said that a normal freezer may achieve slow freezing at -5c wheareas a deep freezer may achieve it at -10c.
Reply: Temperature alone will assure it only if the capacity of the freezer is very high. If the load is high in a refrigerator situation, it will not be able to maintain the -5C. It can warm even to + tempeatures in order to cool down the product. The rate of freezing depends on the rate of heat removal and hence they are dependent on the cooler capacity and product load. By increasing one over the other you can make it depend either on the cooler capacity or product load.
By cooler capacity is he referring to the size capacity e.g. this freezer has a 100litre capacity or is he referring to the engine capacity e.g. this freezer can freeze 2kg of food in 24 hours? Which is it and can you explain how increased capacity(over the product load) cause slow freezing? Also if temperature determines the final equilibrium temperature of the food, why does he say 'temperature will assure it only of the capacity is very high;.