When we use the automatic ice cream production l […]
When we use the automatic ice cream production line, we need to pay attention to many aspects. Among them, there are two major points of attention that we need to consider. Only in this way can we produce high-quality ice cream with a good taste. If you are interested in this knowledge, just read it with me.
1. The amount of air mixed
In the freezing process of the automatic ice cream production line, we need to press in a certain amount of air while stirring strongly, so that the air and tiny bubbles are evenly distributed in the entire mixture. This not only increases the volume of the ice cream, but also improves the texture of the product. The ice cream that is not mixed with air is hard and tasteless. Too much air mixing will increase the volume of the ice cream, but the taste and texture of the product will become poor. The phenomenon of increasing the volume of ice cream by freezing, stirring, and mixing the mixed base material is called compatibilization. The data of the ice cream dairy experiment equipment shows that the expansion of the ice cream is expressed by the expansion rate: expansion rate (%) = (volume of ice cream-volume of mixture) / volume of mixture × 100
The beneficial expansion rate of cream ice cream is 90%-100%, and the fruity ice cream is 60%-70%. Generally, the expansion rate is 2-2.5 times of the dry matter of the mixed raw materials. The expansion rate is also affected by the content of raw materials. When the fat is below 10%, the expansion rate of the product increases with the increase of fat content. The swelling rate of ice cream is better when the non-fat solids are 8%-10%. When the sugar content is between 13% and 14%, it is more appropriate. Too much stabilizer such as gelatin will increase the viscosity and reduce the expansion rate.
2. Freezing temperature
The texture of ice cream is related to the size of ice crystals contained. Only when it freezes quickly can the ice crystals become fine. The continuous soft ice-cream production machine can make the water in the mixture form 5-10 micron crystals, making the product smooth and non-grainy. This requires that the outlet temperature of the industrial ice cream machine should be -6～-3℃. The formation of fine ice crystals is also related to the stirring intensity, the temperature and viscosity of the mixed base material itself. The temperature of the mixture fed into the industrial ice cream machine after maturity should be 2～3℃. If the freezing time is too short during the freezing process, this is mainly caused by the freezing temperature of the industrial ice cream machine or the temperature of the mixed base material being too low. This will result in too little air mixed in the ice cream, uneven bubbles, hard and thick product structure, and poor shape retention.
On the contrary, if the freezing time is too long, it is caused by the freezing temperature of the industrial ice cream machine and the temperature of the mixture is too high, and the content of non-fat solids is too high. As a result, the mixed bubbles disappear, the milk fat coagulates into small particles, the product has poor tissue and poor taste.
After the hardened and frozen ice cream is filled and packaged, it must undergo a low-temperature freezing process for a certain period of time to fix the texture of the ice cream and make the water in the product form very fine ice crystals to maintain a certain softness and hardness of the product. The process is called hardening of ice cream. The ice cream leaving the industrial ice cream machine should harden quickly, otherwise any heating will cause the small ice crystal particles to melt and agglomerate. After hardening, larger ice crystal particles will be formed. At the same time, the tiny air cells will be destroyed and cause shrinkage, resulting in rough structure and reduced quality. The hardening time is affected by the size of the container, the expansion rate, and the freezing temperature. Generally, the hardening temperature is -25～-18℃, and the time is 12-24 hours. The time required for soft ice cream is relatively short.ice cream machine price