The leading food research institute Nofima has recently published a report on the Economic and environmental effects of sub-chilling of salmon
Never has the consumption of seafood been as high as now, and never has it been more important to ensure that the seafood industry becomes a sustainable industry that contributes to us being able to maximize and make use of the best methods for food preservation.
If all Norwegian salmon production was supercooled before transport, the industry could save NOK 1.5 billion (U.S. $150 million) annually in transport costs, according to a recen report from food research institute Nofima.
Sub-chilling of salmon can contribute to reduced emissions of greenhouse gases and reduced costs by reducing the production of ice, and reduced transport and use of packaging material. The main focus of this report is on supercooling of salmon to Europe, but we will also show simple calculations of possible savings related to reduced use of air transport to Asia as well, Said Bjørn Tore Rotabakk from Nofima
Read the full report from Nofima: Here
nanoICE is one of those tools to achieve the goals!
❄ With nanoICE, you can ensure super-cooling of marine products in the entire value chain from Catch to Plate using ice or super-cooled water from our ice machines.
What is super cooling?
Supercooling as a principle is very simple and means that the product is cooled down to between 0 and -2 degrees without being frozen. If you start this early in the process, you need less ice and cooling later in the process to maintain a low core temperature in the product. Nano-ice is made from seawater, is liquid and maintains a temperature of between -3 and -1 degrees. This provides fast and efficient cooling of the products.
Both quality, durability and economic and environmental aspects are improved by this method.
The method has several advantages
- Reduce greenhouse gas emissions: With supercooling, the ice becomes redundant, and fewer trucks and planes are needed to transport the fish. This reduces greenhouse gas emissions from the fuel.
- Save transport costs: Fewer lorries on the road also naturally mean less transport costs.
- Preserve quality for as long as possible: It usually takes about a day before the temperature of the fish has dropped below 0 degrees. Super-chilled fish reaches this temperature much faster, without being frozen.
Through research, the following quality benefits have been documented:
- Longer shelf life: When fish or animals are slaughtered, they go through a process that eventually ends in putrefaction. Supercooling helps to extend the first phase, where the fish is still of top quality, and thus has a longer shelf life than fish that is placed on ice. The shelf life of salmon chilled with ice is around 20 days, while that of super-chilled salmon can be over 30 days with storage at -2 °C.
- Retain liquid during storage: All fish lose liquid during storage. Fillet that is placed on ice has a so-called drip loss of 0.18 per cent per day. Gutted, super-chilled salmon has almost no drip loss during the first four to five days. A study has also shown that super-chilled, vacuum-packed salmon fillets had less drip loss than traditional chilled fillets.
- Better yield: Firmer fish gives more fillet after filleting, and it has also been shown that the yield of cooked fish is higher when it has been supercooled.
Several advantages are also likely, based on knowledge of the raw material and on the basis of experiences from producers who have super-chilled fish:
- Firmer in the fish: Producers who have delivered super-chilled salmon to their customers report fewer complaints about soft fish and fillet splitting.
- Better taste: Producers have received good feedback on the taste of super-chilled salmon.
How to use nanoICE for this purpose
nanoICE gives you control of the temperature and a easy tool to achieve your goal
Chilling of fresh/live fish in either fish farming prior to killing or in reception areas in holding tanks onboard fishing vessels prior to bleeding/gutting
Use 5-10% thin nano-ice solution at -1,2°C to -1,5°C, depending on salinity in the seawater source, is used for this purpose of preventing heat buildup in the raw material in holding tanks / fish reception areas, ideally quickly lowering the raw material temperature from start temperature, without exceeding lower temperatures than +1 to +1,5°C since fish has not been bled or processed.
Maximum recommended storage: 24-30 hours, or until temperatures in fish/ice water exceeds +1°C, without drainage / depending on insulation of holding tanks.
Ice used straight from the machine and/or pumped from an OPTIONAL 1-5t nano-ice storage buffer tank containing the 5-10% thin nano-ice solution in larger volumes on demand.
Chilling of fresh fish after killing/bleeding/gutting/de-heading/grading of farmed fish and/or fresh fish at sea in holding tanks / RSW tanks
Helps bleed the fish better and faster thus also preventing heat buildup in the raw material during this important and heat sensitive processing stage.
Use 15-20% medium thin nano-ice solution at -1,7°C to -2,0°C is used for this purpose of preventing heat buildup and continue/maintain the rapid pre-chilling of the raw material to as close to -0,5°C, prior to either fresh long terms storage in thick nano-ice ( 1-3 weeks as shown in C ), processing and/or blast/plate freezing.
Maximum recommended storage: 36-48 hours without drainage, or until temperatures in fish exceeds -0°C and all the ice has melted. Then either drain all melted ice and re-apply 15-20% nano-ice solution and preserve fish below -0,5°C for another 24 hours / or process the fish / or place fish in thick nano-ice for storage as explained in C) below.
Ice used straight from the machine and/or pumped from an OPTIONAL 1-5t nano-ice storage buffer tank containing the 15-20% medium thin nano-ice solution in larger volumes on demand.
Storage of fresh whole fish (ideally also pre-chilled as in A+B) in drained fish boxes or tubs for 1 – 3 weeks onboard fishing vessels or during transportation in refrigerated cold storage/shipping containers prior to processing
Storage temperature in cold storage/fish hold ideally set to -1°C in order to preserve the nano-ice for the maximum period of time, since nano-ice will cover the fish surface 100% but DOES NOT NEED TO MELT at +2-3°C as conventional ice in order to chill the fish.
Make sure to use ONLY DRAINED TUBS OR BOXES.
35-45% medium thick to thick nano-ice solution at -2,2°C to -3,0°C is used for this purpose, to chill the fish as quickly as possible to the desired and most ideal core storage temperature of -0,5 to -1°C.
For 3-5 days fresh storage: If ice is used straight from the machine without using an agitated nano-ice storage tank, produce ice in the maximum thickness at 35-40% ice concentration.
A setup with a nano-ice system without a nano-ice storage/buffer tank can be suitable for long-line boats and 2-3 day boats, when delivering thick nano-ice into fish boxes or tubs, as the catch is fed evenly into the process from the line. Also in processing facilities when the machine is set to constantly feed thin to medium thick ice into chilling/holding tanks in the processing area.
For 1-3 weeks fresh storage: Thick 40-45% drained nano-ice pumped from a nano-ice buffer/storage tank onto fish in boxes or tubs.
A setup with a nano-ice system with a nano-ice storage/buffer tank is required/highly recommended for all fishing vessels receiving their catch in large volumes each time, like trawlers, gillnetters etc. The machine ́s ice production capacity is set to re-fill the nano-ice storage/buffer tank between catches. (…during 3-5 hour towing etc.)
Storage of fish products (fillets, loins etc.) in thick and drained nano-ice solution for transportation to market in corrugated/Styron boxes (for retail)
Here, the nano-ice storage buffer tank is an essential component of the nano-ice system. The nano-ice buffer tanks are designed to lower the salinity in the ice, increase the ice% and minimize the water content in the ice prior to use in “retail” boxes when required.
The thickest nano-ice at 40-45% ice concentration is produced in the machine and delivered into the nano-ice tank. Temperature in the ice when entering the tank is estimated at -2,8°C to -3,2°C and salinity at 3% on average.
When pumped into the “retail” boxes, the ice % will be closer to 50 to 55%, salinity between 1 to 1,5% and temperature climbed to -2,4°C to -2,7°C.
If the “nano-ice Quality and Cold-Chain” from A to D is practiced, the fresh fish products will ideally be at – 0,5°C when placed in the “retail” boxes (super-chilled) and less ice should be required for a normal transport of 3-5 days to market. If transport time is 6-9 days it becomes even more important to carry out the protocol from A to D above and only use slightly more nano-ice in the boxes.