Cold chain transportation: maintain low temperature transportation
For some products, a few degrees more or less can spell the difference between successful delivery and catastrophic spoilage.Some goods can be safely transported at the temperature in the kitchen refrigerator, while others need deep freezing. Each relies on special techniques to maintain the correct door-to-door conditions.
Let's look at how shippers keep the cold chain intact for several specific types of goods.
When someone is undergoing in vitro fertilization and decides to transfer treatment from one fertility clinic to another, they may ask a professional logistics company to transfer frozen sperm, eggs and / or embryos to a new location.
Eggs and embryos must be kept at a temperature of - 165 ° C. When they need to be transported, professionals in the country of origin store the specimens in a special straw and put them into a tank using dry steam nitrogen as coolant.
Using a special water tank, the temperature can be maintained for up to 72 hours. Use dry steam instead of liquid nitrogen to avoid overflow when the tank tilts on the way. Dry steam provides additional safety during transportation. It can ensure the safety of sperm, whether they cross towns or across the country.
In the competition to distribute covid-19 vaccine, the pharmaceutical industry faces an additional challenge that will not occur if time is not important: some materials used to maintain the cold chain pose a potential safety hazard to aircraft.
One material is dry ice, which expands by 600% when carbon dioxide changes from a solid to a gas. "This gas can replace oxygen," explained Jay Johnson, senior manager of the transportation company.
As this may pose a risk of suffocation in the closed environment of aircraft, regulators restrict the use of dry ice in air cargo.
Shippers cannot avoid this hazard simply by transporting vaccines and dry ice in packages that do not allow the gas to escape. "You can't put dry ice in an airless container because it's easy to explode," Johnson said.
Johnson said the packaging was made by pharmaceutical companies to maintain the cold chain when transporting covid vaccines. In addition, the company successfully argued on behalf of pharmaceutical companies before regulators that the aviation industry could safely increase the amount of dry ice allowed on aircraft.
The systems used by shippers to monitor the temperature of vaccines in transit also pose a challenge, as many of them use lithium-ion batteries, which are considered dangerous goods and are prohibited from being used in the abdomen of passenger aircraft.
Some manufacturers are looking for older technology as a solution. "I had an hour long conversation with a temperature data recorder manufacturer because they had problems with lithium batteries," Johnson said. "They have returned to small charge alkaline batteries to power some of their equipment so that they will not be bound by some dangerous goods restrictions.
The refrigeration manufacturer in York, Pennsylvania sees the pharmaceutical industry as one of its major markets. Alan Klinger, President of the company, speculates that the role of air in transporting covid vaccine may be smaller in the future.
"One day, it will be a more standardized cold chain that needs to be delivered around the world," he said.
This includes places that do not have good air cargo facilities or cannot afford air transportation. Shipping using refrigerated containers can then provide another option.
Some covid vaccines must be kept at - 60 ° C or even lower. But not all vaccines require extreme cold. For immunization with an ideal temperature of - 7 ° C, a new product that can be used to maintain the cold chain is the vaccine freezing monitor (VFM) - 7 ° C of Timestrip, Cambridge, UK.
When preparing to transport a set of frozen vaccine bottles, the user activates the VFM temperature indicator by pressing the button on the back. The monitor then enters the package with the vaccine bottle. If the temperature rises above - 7 ° C at any time, the indicator will display an alarm.
Both fresh and frozen seafood require careful temperature control.
"The life of a fresh product is shortened from the moment it is captured, so it is important that it moves quickly through air or trucks and maintains the temperature at an accurate level throughout the journey," said Alex mckallor, executive vice president and chief operating officer of transportation companies headquartered in Anchorage, Alaska and Seattle. Fresh seafood should not only not be too hot, but also should not be too cold, lest it freeze and no longer ask for high prices.
Mckallor said frozen products require similar management, but because they are less time sensitive, they can be moved by ships or barges and trucks, or stored in refrigerated warehouses.
As a transportation and logistics company, it uses a variety of modes to provide services for all links of the seafood supply chain. "For example, our aircraft will fly freshly captured seafood from other parts of western Alaska to anchorage, and we use barges to transport products with low time sensitivity," mckallor said.
Use refrigerating equipment to transport seafood, and also use ice, gel bags and insulation blanket to protect the cold chain. "It is also important to use a good tray to help ensure the free flow of air so that the temperature of the whole unit can be consistent," mckallor said.
The refrigeration mechanic travels with the cargo on the barge in case of failure. The company also uses advanced technology to focus on seafood moving through air, water or the ground.
"The monitoring function includes the ability to receive an alarm message when the refrigeration unit cannot maintain the required temperature, so that corrective action can be taken immediately," mckallor said.
Transportation companies can remotely adjust the refrigeration temperature and download data from the refrigeration unit to provide a comprehensive audit of seafood journeys.
"Taste tests show that you can't distinguish between tuna frozen and thawed in this way and fresh tuna," klinge said. Companies can save money when shipping frozen tuna instead of fresh tuna because they can ship it by sea in frozen containers instead of by air.