1. Ice cream introduction
Ice cream is a kind of milk and dairy products, adding butter or hardening oil, emulsified oil, eggs and egg products, sweeteners, emulsifying stabilizers, spices and food coloring, etc., through the ingredients mixing, sterilizing, homogenizing, ageing, congealing, hardening and other processes of the multi-phase system composed of solid, gas and liquid, etc.. It is not only attractive in color, smell, taste, and nutrient-rich, cool taste, especially popular in hot summer.
The composition of ice cream is mainly fat, non-fat milk solid, carbohydrates, emulsifying stabilizer, the content of each ingredient according to different types of ice cream and has a greater difference, of which high-fat ice cream total solid and lipid content is highest, followed by the medium-fat, low-fat type ice cream and popsicles, the general popsicle is fat-free, and thus in production, popsicles ingredients are not homogeneous.
2. Ice cream production formula and process
The main ingredients of various ice cream:
Raw material weighing → mixing → pasteurization → homogenization → cooling → ageing → congealing → filling → hardening molding → packaging → cold storage
If the processes improper handling, the product quality, taste and even the cost of profit are affected, especially sterilizing, homogenizing, ageing, congealing, hardening and other processes have a greater influence, which has the greatest effect on homogenizing, it determines the following several processes. Here talk about the homogenizing process in the ice cream production.
3. Principle and function of high pressure homogenizing
The homogenization of ice cream production is the use of high pressure homogenizer. High-pressure homogenization is achieved by the following three physical effects:
Impact: Under high pressure, the moving speed of fat globules is up to 150 m/s or more, high-speed movement of the fat globules and homogeneous valve collision, resulting in fat globule crushed.
Shearing: As the homogenizer valve gap is very small (its height is less than 0.1mm), high-speed flow of fat globules through the gap and has a shear effect, so that the fat globules sheared into smaller fat particles.
Cavitation: High-pressure material suddenly lost pressure at the valve, causing cavitation explosion, so that the fat globule is strongly crushed and refined.
After homogenization, the particle size of the fat globules in the material changed from 5-10μm to 0.5-1.0μm, the particle size was 10% of original, the surface area increased by 100 times, improving the emulsifying capacity of the material, the material in the multiphase system is more stable, less emulsifier to rejection, shorten the ageing time of materials, improve product's delicate sense and smooth sense, effectively prevent the mixture of fat separation and the emergence of the oil spots, increase the viscosity of the material, improve the foaming properties and the expansion rate of the product, which can relatively reduce the cost of the product.
4. Selection of homogenizing process
Homogeneous material quality directly affects the quality of the product, so the right choice of homogeneous technology is an important guarantee for high-quality ice cream. Homogenization has become the key technology to improve product quality in many industries. The homogenization of materials needs to be achieved by the action of shearing force or pressure. At present, the equipment used in homogenizing process mainly includes: high shear homogeneous pump, high shear homogenizer, high pressure homogenizer and so on.
The selection of high pressure homogenizer or high shear homogenizer for ice cream production can refer to our blog "How to Decide Whether a High Pressure Homogenizer or a High Shear Mixer is Your Best Option?". If you have any questions about the ice cream homogenizing process or homogenizer selection, please contact our technical engineer, tell us about your production conditions, expected yield and cost, etc., we can help you determine the perfect homogenizing solution.