Jim Prevor’s Perishable Pundit, October 5, 2006
We’ve dealt both here and here with the issue of Botulism and the recall by Wm. Bolthouse Farms of its 100% carrot juice.
The issue is bigger than carrot juice though. The tie between the Bolthouse recall and the Natural Selection Foods recall is the inching of the fresh produce industry into a food processing industry. At the intersection of eating habits and technology, the way people consume produce is transformed. So a lettuce packingshed is superseded by a modern fresh-cut facility, and a line on which carrots were put in 50 lb. bags is now replaced by a modern plant producing fresh juices.
But the DNA of the produce industry wasn’t established with these products and, in some cases, the rigor of food safety required for processed products isn’t in the culture of the business yet. This is not an issue solely for the actual processing plant. It goes through the entire supply chain.
I was reminded of this when, once again, the Pundit turned to our guru on these subjects, Lou Cooperhouse, Director of the Rutgers Food Innovation Center, for information. The Bolthouse recall is built around the idea that consumer abuse of the product — specifically failure to refrigerate — is the cause of the problem.
Yesterday, we pointed out that there is a dispute as to what the proper temperature should be to keep carrot juice and similar products safe. We also pointed out that many retail cases as well as home refrigerators are not maintained at the proper temperature to safeguard this product.
As follow-up I asked Lou to express the margin of error. Specifically I asked, “If a consumer does refrigerate properly but has the juice in a hot car trunk for 20 minutes, is this enough to create a danger?” Here is what Lou said:
The answer to your question is of course: it depends. As you know, microorganisms can multiply very quickly under optimum conditions. The time it takes for a microbial cell to reproduce is called the generation, or doubling, time. The type of microorganism, type of food, type of technologies that may have been used in the formulation and process, and the storage conditions determine the generation time.
At optimum conditions (like the trunk of a car on a warm day), most microbial generation times range from eight to 45 minutes. At refrigeration temperatures, generation times can be slowed to one to 10 days, if the cells reproduce at all. For spoilage organisms, a slime or odor may begin to appear at one to 10 million microbial cells per gram of food.
For pathogens, the hazardous dose varies. Clostridium perfringens requires 10 to 100 million cells per gram to cause disease, whereas just 10 Listeria monocytogenes cells can cause disease. Therefore, it is important to restrict all microbial growth as much as possible, but you can see how temperature abuse can quickly make a huge difference.
As an example, if the generation time of a bacterium is 20 minutes at 98°F (the car trunk example), then just one cell will generate more than one million cells in less than seven hours at this temperature. The initial contamination level affects how rapidly the food will spoil or become hazardous to humans. The more microbial cells that are initially present, the less time it takes to reach spoilage or hazardous levels.
As you know, the product’s temperature must be maintained at each of the following 12 links in the cold chain:
From the agricultural field to be hydrocooled immediately and shipped under refrigerated conditions to the further processor
Immediately following the processing and packaging process at the factory (which is influenced by the temperature of the room in which product is packaged, whether a continuous chilling process exists, and the length of time it takes for product to reach a refrigerated holding cooler);
In the manufacturing plant’s holding coolers;
At the loading docks of the manufacturer, which can be influenced by the presence of a refrigerated room or the use of insulated packaging and pallet wraps;
During transportation in refrigerated trucks, where pallets of product may go cross-country to a regional distribution center;
On the loading dock of the regional distribution center;
In the cooler of the regional distribution centers or warehouse;
During transportation in refrigerated trucks to the retailer or foodservice operator;
On the loading dock of the individual retail store or foodservice operator;
Inside the holding coolers of the supermarket or foodservice establishment;
In the merchandiser or display case of the supermarket; and
Between the store and home
Your question just had to do with this last link in the cold chain, which is very important, but the actual total time that may occur during this visit from store to home may be just a small percentage of the total shelf life of the product. So as you can imagine, it is easy for the cold chain to be broken. Education initiatives about proper storage conditions are minimal, and there is no consistent and mandatory labeling by our government authorities regarding the recommended storage temperature, the size of the font on packaging to disclose this information, etc.
As a result, various surveys have shown that temperatures of foods in U.S. chilled food distribution channels are frequently in the range of 45F-55F, and much higher during defrost cycles. Coolers are commonly overstocked, and the actual product temperature is far warmer than the thermometer in the case, which is commonly located right near the blower.
The FDA says that a woman is paralyzed from this botulism. Looking at the 12 links in the cold chain, I would speculate that, although it is possible that the failure was in the home, it is exceedingly possible that the product entered the home with too high a bacteria count for comfort.
Attention retailers: Now that you know a slip-up on the cold chain can paralyze a woman — are you really comfortable with the integrity of your cold chain? Not on average, not what the thermometer says but that each item — — no matter where placed in the case, even during defrost cycle — is actually maintained at proper temperature?
And, do you double-check manufacturers’ recommendations? Manufacturers need to sell product. They may have an inclination to be on the outer edge of the safe range especially on minor products where if they make the retailer’s job too tough, he won’t carry the product.
You should be getting advice from guys like Lou Cooperhouse. I have his phone number.