Freezing Solutions for Meat and Poultry Processing: How to Configure Lines for Cut Meat, Whole Poultry and Braised Cooked Foods

Quick freezing in meat and poultry processing is not simply about pulling the temperature down to -18℃: cut meat carries bones and fat, whole poultry has body cavities, and braised cooked products still carry a core temperature of 60~90℃ — these three material types travel different paths through equipment. Wrong equipment configuration produces different problems too — thin sections frozen through while thick sections haven’t reached temperature, cavities not frozen through, cooked foods sitting too long in the danger temperature zone. Below, these three lines are discussed separately, with all parameters taken from publicly available technical data for Kunning Cryo liquid nitrogen quick freezing equipment.

TL;DR

For continuous production of fresh cut meat and whole poultry, use the liquid nitrogen tunnel line DKN-LFT, controlling core temperature through belt speed and zoned injection.
For plants with many varieties and small batches (a few hundred kilograms per batch), configure the liquid nitrogen cabinet DKN-LFC; switching products only requires changing loading and parameters.
Braised and steamed cooked products cannot go directly into the freezing section; first pass through the dual-cabinet rapid cooler DKN-RHC to bring them down to a safe temperature, then into the tunnel or cabinet machine.
The common red line across all three lines: discharge center temperature below -18℃, and passing through the -1℃ to -5℃ ice crystal formation zone within 30 minutes.
Nominal capacity values vary with material form, piece weight and packaging; conduct a full-load test with your own products before production startup.

1. Four Differences in Meat and Poultry Materials

Bone-in and skin-on, discontinuous heat conduction paths. For bone-in pieces such as chicken legs, chicken wings and pork ribs, the thermal conductivity of meat, fat and bone differ considerably; the bone edge tends to reach temperature first while thick meat lags. Setting freezing time by average thickness of a single piece often fails to meet the temperature criterion.

Whole poultry has cavities. The abdominal cavity of whole chickens and ducks is a closed air cavity that cold air cannot enter, so cooling relies solely on conduction from the outer surface inward. Cavity temperature is a key measurement point for whether the equipment meets requirements — it is not optional.

Wide range of piece weights. The same workshop may have 20 g chicken breast slices and 2 kg whole ducks; the tunnel line must be able to match different loadings through speed adjustment and zoned injection.

Cooked products need cooling first, then freezing. Braised and steamed products come out with a core temperature of 60~90℃; going directly into the freezing section would cause severe fluctuations in the equipment cavity temperature, and the freezing results of the first half and second half of the same batch would not match.

Working area of the liquid nitrogen tunnel line belt loading

2. Fresh Cut Meat and Whole Poultry: How to Set Tunnel Line Parameters

The liquid nitrogen tunnel line is a SUS304 mesh belt passing through multiple insulated tunnel sections, with zoned liquid nitrogen injection inside the tunnel, and materials passing through in a single layer or thin layer. Taking DKN-LFT-1212 as an example:

Item	Parameter
Tunnel belt	12000 mm (length) × 1200 mm (width)
External dimensions	12000 × 2250 × 1670 mm
Working temperature	-150℃ ～ ambient
Temperature control accuracy	±2℃
Cooling rate	Up to 10℃ per minute at no load
Freezing capacity	1 m³/h (depending on material and packaging)
Total power	18 kW
Refrigerant	5-8 BAR liquid nitrogen (storage tank self-provided)
Oxygen concentration monitoring	Set value 19.5%-21.5%
Conveying cycle	5～25 minutes adjustable (belt speed adjusted by material)

The decision to choose this line is based on three numbers: daily output, single piece thickness, and available workshop length. A 1.2 m wide, 12 m long body means one line spreads out in one direction; for thick pieces exceeding 60 mm in single piece thickness, either reduce speed to extend residence time, or reduce loading layers — speeding up the belt cannot compensate.

The whole poultry cavity issue is relatively easy to handle on the tunnel: before loading, spread open the cavity or fix it with shaping rods so cold air can enter the cavity; at the same time, set the belt speed based on “cavity reaching temperature” rather than “surface reaching temperature,” and during post-discharge sampling, insert the probe deep into the cavity to measure.

3. Many Varieties, Small Batches: How to Use Cabinet Machines

For scenarios with frequent product changes and single batches of a few hundred kilograms, tunnel lines are difficult to schedule; cabinet machines are more suitable. Parameters of DKN-LFC-600:

Item	Parameter
External dimensions	2900 × 1700 × 2450 mm
Common working temperature	-150℃ ～ ambient
Temperature control accuracy	±1℃
Temperature uniformity	±3℃
Cooling rate	Not less than 20℃/minute (no load)
Capacity	600 kg/h (varies with different products and packaging methods)
Total power	5 kW
Refrigerant	5-8 BAR liquid nitrogen

The cabinet machine’s circulating air field breaks up cold air and forces circulation; air velocity uniformity directly determines the temperature difference between trays in the same batch. When loading, leave air passage gaps between trays — this preserves temperature uniformity better than stacking trays full; loading a cabinet “full” versus loading it “through” produces visibly different product quality after discharge.

4. Braised Cooked Products: First Through the Danger Temperature Zone, Then Freeze

The first step for cooked products is not freezing — it is cooling. Once the 60℃ to 10℃ segment is completed, the microbial growth risk window is closed, and only then does quick freezing come into play. The dual-cabinet rapid cooler DKN-RHC-60D handles this segment:

Item	Parameter
Structure	Dual cabinets in parallel, single cabinet cavity 580 × 720 × 1430 mm
Loading	60 standard trays per cabinet, 3~5 kg per tray, approximately 200 kg/batch per cabinet
Inlet temperature	60~90℃
Outlet temperature	3~10℃
Single batch cooling time	1~2 hours (depending on material and loading)
Cabinet internal temperature	Down to -45℃
Refrigeration	4.55 kW compressor, selected by model
Power supply	220V or 380V / 50Hz

The two cabinets are controlled separately, allowing one cabinet to be cooling while the other is loading or unloading, connecting upstream and downstream processes. After cooked products are cooled to 3~10℃ and enter the quick freezing tunnel or cabinet, the equipment’s cooling capacity is spent only on “freezing” and will not pull up the tunnel cavity temperature due to excessively high inlet temperature.

Loading and unloading side of the dual-cabinet rapid cooler in the cooked products workshop

5. Loading and Arrangement: Three On-Site Actions

Single-layer flat placement, don’t stack. Stacking two layers on the tunnel belt means the lower layer is blocked from cold air by the upper layer, and the temperature difference between top and bottom at discharge is noticeable. Handle excess volume through speed adjustment and extended residence time, not by stacking higher.

Feed in batches by piece weight. When a batch mixes 50 g and 500 g pieces, by the time thick pieces reach temperature the thin pieces are over-frozen, and moisture loss and cracking both increase. Feed in batches so equipment parameters can match.

Separate cooked products from fresh products on the line. Cross-contamination between raw and cooked is the first issue caught in audits: equipment, trays and personnel passages must all be separated; when the same equipment handles both raw and cooked products, the cleaning and sanitizing in between must be written into the operating procedures.

6. Selection Comparison

Scenario	Recommended Equipment	Basis for Decision
Single category continuous production, daily output in tons	Liquid nitrogen tunnel line DKN-LFT-1212／1612	Belt width and body length can fit into the workshop, fixed category
Many varieties, batches of a few hundred kilograms, order fluctuations	Liquid nitrogen cabinet DKN-LFC-600／LFC-1500	Switching products only requires changing loading and parameters, no line changes
Cooling section for braised and steamed cooked products	Dual-cabinet rapid cooler DKN-RHC-60D	Approximately 200 kg per batch, 1~2 hours to 3~10℃
Laboratory, new product sampling	Liquid nitrogen cabinet DKN-LFC-300	Small batches, parameters can be adjusted repeatedly

FAQ

Can tunnel lines and cabinet machines be configured on one production line?

Yes, but the division of labor must be clear: the tunnel line handles continuous freezing of main product categories, and the cabinet machine handles small batches, new products and rework batches. The feeding rhythm and tray specifications of the two lines should be unified as much as possible, otherwise the transfer step will add an extra tray transfer and an extra exposure.

By what thickness should freezing time be set for bone-in pieces?

By the distance from the bone edge to the surface, not by the overall external dimensions. For flat bone-in pieces like pork ribs, take the meat thickness between two adjacent bones as the control dimension; for pieces with bone at one end like chicken legs, take the thickness from the bone end to the surface, and during post-discharge sampling, insert the probe to the position adjacent to the bone for temperature measurement.

After cooked products are cooled to 3~10℃, how long can they wait before freezing?

The shorter the waiting time between cooling and entering the freezing section, the better; the specific duration should be set according to your own product’s microbiological indicators and workshop temperature, and written into the operating procedures. What the equipment side can do is match the rhythm of the cooling cabinet and the freezing section so materials don’t pile up waiting in the intermediate step.

How to estimate liquid nitrogen consumption?

Calculate by material weight, inlet temperature, target core temperature and equipment heat loss — not just by capacity multiplied by a coefficient. Before production startup, conduct a full-load test with your own materials, record the liquid nitrogen usage per batch, and then work backward to determine the procurement cycle and storage tank capacity.

Next Step

Send us your product form (cut pieces／whole poultry／cooked products), single piece weight, daily output and available workshop length, and we will provide a production line configuration recommendation based on these three items. Leave a message here: Contact Us.