Quick-frozen foods are foods that need to be frozen. After proper pre-treatment, they are quickly frozen in various ways. They are packaged and stored at -18°C to -20°C (generally required, different food requirements are different). The best advantage of low-temperature products at the point of consumption is to preserve the original quality of the food at a low temperature (to reduce the heat inside the food or to support various chemical activities, while freezing part of the free water of the cells, and reducing the water activity) Without the use of any preservatives and additives, while preserving food nutrition to the maximum extent possible. It has the advantages of delicious, convenient, healthy, hygienic, nutritious and affordable (staggered seasons, improved food value, and higher efficiency).

advantage

Generally speaking, the quality of quick-frozen foods is always higher than that of slow-frozen foods. Quick-frozen can well avoid the adverse effects caused by the growth of ice crystals on frozen food during the freezing process, thus affecting the taste and nutrition of foods. Add any preservatives and additives.

Traditional food quick freezing equipment

Tunnel type food liquid nitrogen quick freezing machine

The difference between liquid nitrogen food quick freezing equipment and traditional food quick freezing equipment

First, the comparison of quick freezing equipment

As can be seen from the above figure, the traditional quick freezing equipment is a relatively large and complex system, and the liquid nitrogen quick freezing equipment is relatively simple, so the liquid nitrogen quick freezing machine has several advantages:

1. The initial investment cost is small. 2. Small footprint. 3. Simple maintenance and low maintenance costs. 4, easy to clean. 5, easy to operate, no professional and technical personnel. 6, easier to install. 7, strong mobility. 8. The energy consumption of liquid nitrogen quick-freezing machine is very small, while the traditional quick-freezing machine is powered by energy consumption!

The main features of various types of food quick-freezing process and their comparison are as follows:

Comparison item

mechanical

Ultra-low temperature

Impact type

Cost structure

High initial fixed asset investment, low operating costs, and extremely high labor costs

Small initial fixed asset investment, high variable cost, low labor costs

High initial fixed asset investment, operating cost is slightly lower than food ultra-low temperature quick freezing, but higher than traditional mechanical food quick freezing equipment

Factory installation positioning

The position is fixed, usually fixed on the prefabricated concrete foundation, and the installation is limited by the space of the site.

Easy to move, small footprint, flexible location

Slightly mobile compared to mechanical

The refrigerant

Usually use ammonia, freon, ethanol, etc. as a refrigerant

Refrigerant is liquid nitrogen

Usually use ammonia, freon, ethanol, etc. as a refrigerant

Food quick freezing effect

Slower, due to the use of relatively high temperature refrigerant, the temperature is generally below tens of degrees, the product effect is not obvious

Extremely fast, the refrigerant temperature is extremely low, the lowest temperature can reach 196 degrees below zero, the quick freezing effect is remarkable, and the product quality is good.

Faster, the restrictive condition is that the food must be flat and the thickness cannot be higher than 20mm, the product effect is not obvious

Summary: These three types of food quick-freezing process types, including tunnels, spirals, single quick freezing, and fluidized beds, are applicable. By comparison, the optimal equipment system in these three types of food quick-freezing processes is the “ultra-low temperature” freezing process, namely liquid nitrogen quick freezing equipment.

Liquid nitrogen quick freezer compared to conventional refrigeration equipment

Comparison item

Traditional quick freezing machine

Liquid nitrogen quick freezing machine

Operating temperature

0°C- 35°C

0°C- 196°C

Temperature control accuracy

3°C - 5°C

1°C - 2°C

Insulation material

150mm polyurethane foam double-sided stainless steel insulation board combination installation

Double-sided food grade SUS304 stainless steel 150mm overall foam insulation

Control System

Industrial PLC automatic control system

Touch screen + PLC Chinese and English automatic control system, with manual and automatic modes; using imported German liquid nitrogen circulating atomization spray system, liquid nitrogen vaporization evaporative refrigeration system (patented technology)

The refrigerant

Liquid ammonia - has a severe pungent odor, the concentration is excessively suffocating or dying

Freon - destroying the atmospheric ozone layer, has been banned internationally

Liquid nitrogen - non-toxic, colorless, odorless, clean inert gas

Cooling System

Mainly by compressor, condenser, accumulator, solenoid valve, filter, expansion

Expansion valve, evaporator, gas-liquid separator, etc., its structure is very large

Miscellaneous, careless and inconvenient to maintain

Mainly composed of solenoid valve and evaporation nozzle, the structure is simple and easy to maintain.

Quick freezing time

2-5 hours

5-40 minutes, extremely fast freezing

Productivity

Due to high freezing temperature, slow freezing rate and long time, resulting in low production efficiency

Due to the extremely low freezing temperature, the freezing time is fast; the output per unit time is large, and the freezing speed and efficiency are more than 3 times that of the traditional freezing equipment.

Process technology

The freezing time is long, the ice crystals formed inside the food are large and uneven, the cell membrane and the cell wall are pierced by the great ice crystals, the nutrient juice is lost after thawing, the food loses the taste, and the original flavor of the food is lost.

Ultra-low temperature refrigeration, short freezing time, rapid formation of ice crystals with small distribution and uniform distribution inside the food, intact preservation of cell membrane and cell wall without damage, no loss of nutrient juice after thawing, keeping the taste of food unchanged, fully maintaining the original food Flavor, original flavor

Dry water consumption

Due to the difference between the freezing technology and the principle, the traditional frozen food will have a large amount of water loss during the freezing process, usually the loss rate is 3%-7%.

Liquid nitrogen quick freezing technology, due to the obvious difference between its principle and the traditional one, the dry consumption of the product frozen by liquid nitrogen quick freezing technology

Between 0.6% and 1%

Food effect

Because the refrigerant is unsanitary, environmentally friendly and corrosive, food safety is not guaranteed.

Liquid nitrogen is an inert gas. The food shelf life of the frozen food is more than three times that of traditional refrigeration equipment. It is easier to get QS certification by using liquid nitrogen quick-frozen food.

                               Energy loss

Calculate the power consumption of 300-600KW in units of one ton of food

Calculate the consumption of liquid nitrogen in units of 1 ton of food, about 0.5-1 tons

Cleaning and maintenance

Due to the large size of the equipment and the complicated structure, the cleaning is extremely inconvenient and troublesome, and the maintenance cost is large.

The machine body is simple and the equipment can be flexibly mobilized. It can be washed directly with water, and the maintenance cost is very low.

Floor area

Due to the large size of the equipment, the complexity and complexity of the structure, and the large floor space of the equipment, the investment cost of the factory lease is large; the equipment floor space and rental expenses are usually more than double the liquid nitrogen body.

The machine body is simple and compact, and it has a small footprint. It can flexibly move the device position due to processing or factory relocation requirements.

Labor costs

The equipment has a large body, many structures and complex structures, and many and complicated control procedures. It requires sufficient personnel to look after and control, resulting in high labor costs.

Touch screen + PLC Chinese and English automatic control system, simple and convenient to operate, one-click operation to say goodbye to cumbersome settings, no need for a large number of personnel care and control, saving talent recruitment costs