The Cold Chain

Conceptually, the problem of refrigerated transport and distribution is to maintain a proper chilled (or frozen) temperature from the point of food processing up until the point of usage of the product (retail sale or consumer usage). This maintenance through warehousing at the shipping point, through shipping, reception at the primary distribution point, and finally through the handling at the retail location is called the cold chain. Because of the growing complexity of distribution systems, and the consequent difficulty of control, it is becoming necessary to create systems that will monitor a product from the beginning of the cold chain to the end.

Temperature Monitoring

For many years people have used mechanical or electronic temperature recorders to check temperatures of perishables in transit. Monitoring of this important link in the cold chain has been called transit monitoring. Transit monitoring has historically been achieved by the use of ‘graphic recorders’. Graphic recorders are usually battery-powered devices that produce a long strip chart of a time-temperature recording. More recently, the use of electronic recorders has become the dominant technology in transit monitoring, but problems remain. Certainly, transit temperature monitoring is a crucial and ongoing activity that checks this important single link in the cold chain, but there are more links than just the shipping of a product by truckload from processor to distribution centers.

Problems Affect Food Quality and Safety

For the past several years, there has been a growing awareness that inadequate temperature management throughout the cold chain is harming the safety and quality of the food supply. The cold chain is growing in length and complexity. It has become evident that new technology is needed to augment existing monitoring approaches, especially since distribution of perishable products involves packages going to many locations, where temperature conditions can vary tremendously.

The only effective way to perform the essential monitoring of the full cold chain is at the package level. Packages cannot be monitored by normal transit monitoring tools. The answer is to use “time-temperature indicators” or “TTI’s”. These are adhesive labels that respond to the temperature history of the package they are applied to— they give a visual signal that the exposure to temperature, over time, means that the product is not safe, fresh or wholesome.

A Safe Food Supply - HACCP

The problem is an important one. The need for improved methods to secure safe food products of highest possible quality to the consumer is presently an item of great concern to governments and their respective health authorities throughout the industrialized world, with the US and the EU taking the lead in active programs.

According to estimates by Food and Drug Administration (FDA) and US Department of Agriculture (USDA), in the USA about 9000 deaths and up to 33 million illnesses every year are food related. The annual societal costs are calculated to approximately 35 billion dollars, representing loss of production and increased costs for health care and premature deaths.

Agreement is widespread that organized programs are required for full cold chain monitoring as a means for approaching the problems of temperature abuse in food distribution. Of the various organization schemes is HACCP, or Hazard Analysis Critical Control Point.

HACCP will ultimately become an across-the-board regulatory mandate based on food safety concerns. On-package sensors. however, are another story. In most cases, the current approach, which is favored by the processors and packers with regard to on-package indicators, is a food quality criterion. What is not so apparent is that the use of TTI labels an consumer packaging will have an appreciable impact on food safety. Processors are aware that if they start a program of consumer-readable TTI’s, they will avert the force of legislation that will eventually require them.

TTI’s are a natural tool for HACCP programs since the result is a single point of decision: the TTI indicates “OK’ or “NOT OK” by its color display. This makes it easily possible for points of control to be modeled after the programmed response characteristic of a specific TTI.

International Food Safety Actions

Various initiatives in the European Union (EU), have tested and approved the use of TTI’s for seafood and other commodities. Dr. Petros Taoukis of the National Technical University of Athens has produced an exhaustive study for the EU PAIR program that focuses on the use of TTI's, especially for seafood. TTI mandates are currently in force for airline catered food in Great Britain, and other activities and food categories are slated for the EU states in broad application.

CheckPoint^® Takes Its Place in TTI History

The TTI technology behind our CheckPoint® I was developed in Sweden over twenty years ago. It’s original conception was based on the need to track the shipment of temperature sensitive pharmaceutical products, but it became evident that the broader application to food transport and distribution might be more significant.

Over the years, the technology went through multiple ownership, and at one time development was funded by the Swedish government at sponsored laboratories in Malmö, Sweden. Early introductions were made to US markets under the brand name of I-Point, but funding and needed technological delayed the commercialization of the product.

By 1995, a group of Swedish and Swiss investors revitalized the company under the company Vitsab, AB, a Swedish corporation. Vitsab, AG attracted the attention of Dow Chemical, who assisted with financing and supported testing of the product with the import of farmed salmon from Chile to US markets. The trial successes convinced Dow to move towards acquisition of Vitsab, AB. Dow backed out due to the unusual financial stresses in 1997, and one of the US companies cooperating with Dow, Cox Technologies, Inc., partnered with Vitsab, AB over the next several years. The technology was refined, and manufacturing was set up in the US, and market studies for the product were launched. Cox acquired the technology and the company in 1999. The first commercial sales of the product took place in 2002, after much technological development and supportive scientific study established the effectiveness of the product, now known as CheckPoint®. Now CheckPoint® is under private ownership, but continues to make progress in TTI technology.

TTI’s as a temperature and food monitoring technology are now just coming into market acceptance. The CheckPoint® product is a dominant technology in this arena, inasmuch as virtually all of the published scientific studies that validate the use of TTI’s with food processes were sponsored by the CheckPoint® company entity or its predecessors, or involved the use of the CheckPoint® technology. CheckPoint® experts are acknowledged worldwide for the depth of their knowledge of TTI monitoring and have made symposium presentations on over 50 occasions in the US and other locations.

The CheckPoint^® III Paradigm Shift

In addition to its distinction as a scientific and industry leader, Vitsab has been continuing to seek TTI product improvement for its customers. Vitsab’s CheckPoint® III has recently been introduced and is emerging as a technology with some unique advantages: a clear color endpoint (amber to bright pink) , simple high-speed activation, trouble-free storage and high temperature performance, and a price that promises to bring item-level TTI labeling into practical reality. 

Regulatory Agency Endorsement in the US

At the present time, there is no official endorsement of CheckPoint® TTI technology by any US Regulatory agency (or any other TTI product, for that matter). TTI's are recommended in several Federally published HACCP guideline documents. and are listed as an appropriate means for certain types of critical monitoring. There are informal indications from a wide range of governmental authorities that indicate that the technology will have the full support of regulatory bodies.

The ground beef industry is coming into compliance with regulatory mandates for TTI's or similar controls on all packages in distribution to retail sale points.

A Cost Effective Tool in Marketing

Early in the history of TTI’s, it was contemplated that the technology would play its most significant role in protecting ROP packages from the threat of anerobic toxin-forming or illness-causing bacteria, the primary threat to the widespread use of ROP shelf life extension in the food industry. For the present, this application has been a primary use of TTI, and the CheckPoint® TTI is no exception. A greater role has been trial tested on many occasions, and that is the use of CheckPoint® as a direct replacement for shelf life dating systems for product rotation, consumer advisory and in-store perishables management.

Real world testing has shown CheckPoint® to be highly effective at the retail interface. The cold chain concept has come full circle: the public demands safe, fresh and wholesome foods, and is willing to pay for them. CheckPoint® is there to allow the food industry to truly fulfill that demand. The technology has taken a long and winding road to reach its present position, and now will have a significant role to play.