In the food industry, keeping food fresh and of high quality is very important. Liquid nitrogen freezing machines help by cooling food quickly and evenly. This ensures that the food stays fresh after being frozen. SPEEDCRYO, a company with 10 years of experience in cold chain technology, is a supplier of equipment and solutions for freezing food. Their technology helps improve food quality and make businesses more competitive. By using liquid nitrogen freezing, companies can extend the shelf life of food and increase their profits.

1. How Liquid Nitrogen Freezing Works

Liquid nitrogen freezing machines use very cold liquid nitrogen at -196°C to quickly cool food below its freezing point. This quick cooling process takes only a few minutes and prevents water in the food from forming large ice crystals that can damage the food. This way, the food keeps its original nutrients and taste.

Liquid Nitrogen’s Features

Liquid nitrogen is a colorless and odorless gas that boils at -196°C. When it absorbs heat, it quickly turns into gas, taking away a lot of heat. This makes liquid nitrogen perfect for freezing food quickly.

• Low Temperature: Liquid nitrogen’s extremely low temperature cools food quickly and prevents bacteria from growing, while also slowing down the food’s oxidation process.
• High Heat Absorption: When liquid nitrogen changes from liquid to gas, it absorbs a lot of heat. This quickly reduces the temperature of the food.

The Cooling Process

The freezing process of liquid nitrogen involves quickly cooling the food to below its freezing point in a few minutes. The steps are:

• Contact Cooling: Liquid nitrogen is sprayed or dipped onto the food. The surface of the food cools down very quickly, reaching around -196°C in seconds.
• Heat Transfer: The heat from the inside of the food quickly moves to the surface, and the cold nitrogen gas continues to absorb the heat. This cooling process finishes in a few minutes, preventing the formation of large ice crystals, which can damage the food.

Ice Crystal Formation

The key advantage of liquid nitrogen freezing is that it creates very small and even ice crystals.

• Fast Freezing: Because the temperature is so low, the water in the food freezes quickly. Since the process is fast, the water molecules don't have enough time to form large ice crystals. Instead, they form many small ice crystals, which do not break the food cells.
• Less Dehydration: Unlike slow freezing methods, liquid nitrogen freezing reduces dehydration. In slow freezing, water can move and form large ice crystals, damaging the food cells and causing water to leak out. Liquid nitrogen freezing locks the water inside the food, so when it is thawed, it returns to near-fresh condition.
• Enzyme Activity Reduction: Liquid nitrogen freezing also stops enzymes in the food from working. This is important for foods like fruits and seafood that spoil easily, as it helps them stay fresh longer.

2. Structure and Working Process of the Liquid Nitrogen Freezing Machine

A liquid nitrogen freezing machine usually consists of the following parts:

Liquid Nitrogen Tank

The liquid nitrogen tank stores and supplies liquid nitrogen to the freezing machine. It is made of high-strength stainless steel and has good insulation to prevent the liquid nitrogen from evaporating too quickly.

Freezing Cabinet

This is where the food is frozen. The cabinet is sealed to keep the cold air inside and ensure efficient freezing.

• Sealed Design: The cabinet is fully sealed to keep the cold temperature inside and save on liquid nitrogen use.
• Temperature Control System: Sensors inside the cabinet monitor the temperature, adjusting the amount of nitrogen and freezing time based on the food.

Liquid Nitrogen Spray System

This system evenly sprays liquid nitrogen onto the food to cool it quickly.

Nozzle Design: The nozzles are designed to spray the liquid nitrogen in a fine mist, ensuring that every part of the food is cooled evenly.

Control System

The control system is the “brain” of the machine, monitoring and adjusting the freezing process.

• Smart Control Panel: Operators can set freezing time and liquid nitrogen flow using the control panel. High-end systems have touch screens that make the machine easy to use.
• Fault Detection: The system also has fault detection that alerts the operator if there is a problem, making it easier to fix any issues.

3. Advantages of SPEEDCRYO’s Liquid Nitrogen Freezing Machines

As a leading brand in liquid nitrogen freezing equipment, SPEEDCRYO offers many advantages:

• Energy-Saving Pre-Cooling Technology: This feature allows SPEEDCRYO machines to use leftover cold nitrogen gas to pre-cool food in another chamber, reducing freezing time and saving on liquid nitrogen use.
• User-Friendly Multi-Language System: SPEEDCRYO machines are easy to operate, with a user-friendly system that allows customers to start freezing without needing to read a manual.
• Versatile Applications: SPEEDCRYO machines can freeze various types of food, such as meat, seafood, fruits, and vegetables.