Posts Tagged “controlled atmosphere”
By CarrierTransicold
Building on the pioneering legacy of the refrigerated container shipping industry’s first controlled-atmosphere system 25 years ago, Carrier Transicold has developed the next-generation EverFRESH® system, which makes premium performance more affordable than ever for fleets and container leasing companies. Carrier Transicold is a part of Carrier, a leading global provider of innovative heating, ventilating and air conditioning (HVAC), refrigeration, fire, security and building automation technologies.
Using active controlled-atmosphere technology, the EverFRESH system optimizes the balance of oxygen and carbon dioxide within a refrigerated container, slowing respiration and the natural ripening of the commodity inside. Thus, it helps to preserve the quality of perishables beyond what refrigeration alone can do. As an active system, it generates high-purity nitrogen to more quickly and responsively displace oxygen, rather than relying on respiration alone to gradually reduce oxygen levels.
“The active nature of the EverFRESH system can handle a broader range of perishable commodities than modified controlled-atmosphere systems, making it a more versatile choice for many customers,” said Jim Taeckens, senior product manager, Global Container Refrigeration, Carrier Transicold.
“Another key benefit of the EverFRESH system’s active technology is that it maintains a positive air pressure within the container, making it far less sensitive to box leakage than other types of systems,” Taeckens explained.
Key components are a sensor package, nitrogen membrane separator, air compressor and air filters. In use, the compressor pulls fresh air into the system, which then removes water vapor from the compressed air stream before it enters the membrane separator. The hollow-fiber media of the separator extracts oxygen and captures carbon dioxide, discharging concentrated nitrogen into the container. If supplemental oxygen is needed, the membrane can be bypassed. The EverFRESH system can independently maintain oxygen at user-selected levels between 3 – 17% and carbon dioxide at between 2 – 19%.
Optional ethylene absorbers can be added for perishables where elevated levels of the hormone are a concern.
All EverFRESH systems have pre-trip inspection routines that test the membrane and compressor to make sure they are functioning normally prior to use.
The new EverFRESH system will be available in early 2020 for Carrier Transicold PrimeLINE® refrigeration systems equipped with the Micro-Link® 5 controller option.
“Carrier Transicold was the first to introduce the container shipping industry to the advantages of controlled-atmosphere shipping with our EverFRESH system,” Taeckens said. “While the original design had a very strong following, the costs associated with its components and associated controls limited its adoption. Today, our technology has improved to the point that we are pleased to be able to offer an active system that is significantly more affordable. It is also much less complex and easier to service than competitive systems.”
With the new EverFRESH system, Carrier Transicold now offers customers a choice of two controlled atmosphere options, the other being XtendFRESH™, a modified system that uses a scrubber to remove carbon dioxide and ethylene from atmospheres within a container.
About Carrier Transicold
Carrier Transicold helps improve transport and shipping of temperature-controlled cargoes with a complete line of equipment and services for refrigerated transport and cold chain visibility. For more than 45 years, Carrier Transicold has been an industry leader, providing customers around the world with advanced, energy-efficient and environmentally sustainable container refrigeration systems and generator sets, direct-drive and diesel truck units, and trailer refrigeration systems. Carrier Transicold is a part of Carrier, a leading global provider of innovative HVAC, refrigeration, fire, security and building automation technologies.
In this series we have been covering a number of issues and answers coming out of the study Comparison of Pallet Cover Systems to Maintain Strawberry Quality During Transport.
The study was conducted by the University of California, Davis and The University of Florida.
While a primary goal of the study is to find better ways to have produce with better quality and flavor delivered from the field to the kitchen shelf, transportation plays a key role in this.
Rich Macleod of TransFresh Corp. describes this as a “global process” where it must be considered that actions taken during the entire handling process can influence even the best varieties of product that end up in the hands of the consumer.
“The study confirms my private belief, plus our private research over the years,” he says. “If you do these processes correctly; cool it, transport correctly with good temperature control, with a CO2 atmosphere, you are going to deliver better fruit to the consumer.”
In the report, it details strawberry shipments with palletized loads covered with bags and carbon dioxide (CO2). The transcontential shipments compared the modified atmosphere shipments of CO2 West, PEAKfresh, PrimePro and Tectrol (TransFresh).
The results of the study may show why Tectrol is the dominant supplier of bagged, controlled atmosphere shipments out of California. Macleod says over half of the California harvested strawberries in California are shipped using the Tectrol process by TransFresh. California also grows and ships the vast majority of the nation’s strawberries.
The summary of the study’s findings probably explains why many strawberries look great when shipped and still are beautiful when displayed in your local supermarket. However, how many times have you purchased strawberries in the store and no sooner get home and notice quality problems occuring (a common experience with yours truely, the purveyor of this website)?
The study summarizes, “The Tectrol cover was sealed to the pallet base, a partial vacuum was applied, and pressurized CO2 gas was injected inside….CO2 concentrations within pallets at the beginning and end of transport were higher (11% to 16%) in the sealed Tectrol system and relatively low (.06% to .30% in the open CO2 West, PEAKfresh and PrimePro cover systems.”
Continuing, the report states, “The incident of fruit decay was low (1% to 1.4%) after transport, but increased substantially following a 2-day shelf life at 68 degrees. However, fruit from the Tectrol pallets exhibited significantly less decay (36%) after shelf life than the CO2 West (39%), non covered (pallets)(41%), PrimePro (42%) and PEAKfresh (43%).”
(This is Part 3 0f 5, featuring an interview with Rich Macleod, vice president, pallet division North America for TransFresh Corp., Salinas, CA. He has been with company since 1976, and has a masters degree in post harvest science from the University of California, Davis.)