Danger of Buying Chicken from Supermarket
Submitted by Robert D. Lucas, PH.D and CFS, Food bio-technologist
Over a two-week period in July 2019, I purchased four frozen chickens (1.8 kg each) at different times from a Supermarket which had them on a special sale, at about ten-dollars lower than those held on the chill-counter. It was obvious that the birds had been held on the chill-counter and then transferred to the cold-storage for freezing: As there was some dispute about the frozen state of the first one purchased (it was semi-frozen and according to the check-out did not meet the conditions of the special, which specified frozen and was still in the livery of the company that produced and packed it). There were no untoward problems with the first three birds (sensory appraisal-smell was normal and there was no surface slime caused by Pseudomonas spp. and other cold tolerant microbes). The final bird purchased was thawed in several changes of water at ambient temperature and after ninety-minutes eviscerated. There were visible as well as sensory signs of microbial contamination of the inserted offal meats. The following is written from a food safety and consumer aspect.
In an article written by me and published in the Advocate of the 25th. July 2001, under the caption “Just how safe is the meat we import?” I replied to some comments made by Dr.Trevor King, the senior veterinarian officer where he asserted that: “labeling of meats with the country of origin was needed, especially in cases of imported poultry (chicken). He alluded to the practice of thawing and refreezing of imported poultry and that to prevent the practice, it was necessary to stop the importation of large amounts poultry at any one time.” I pointed out that the Food Safety Inspection Service (FSIS) of the United States Department of Agriculture (USDA) had verified the safety and wholesomeness of meat thawed and refrozen several times once the process was done under refrigerated conditions (under these conditions there are some losses in water- and salt-soluble proteins content of the meat). I, however agreed with him that there was a need for proper labeling so that the consumer could make informed choices as to whether or not to purchase the product. At that time, representatives of the Barbados Agricultural Society (BAS) were hollering and keeping a lot of noise over the need to ban the thawing and refreezing of poultry meat. The BAS also claimed that there was no real market for frozen poultry; that Barbadians preferred the chill product.
What I am concerned about in this instance is the absence of labeling, indicating that the product was held for three-five days on the chill-counter before being held under cold storage conditions. I have no problem with the practice since the birds were slaughtered and packed under hazard analysis critical control point (HACCP) conditions and (because the micro-flora presence are relatively harmless and are easily destroyed by adequate cooking and Barbadians over cook their foods) I am averse to the wastage of food, but the consumer must be informed. It is noticeable that the BAS (the hypocrites) are not hollering and shouting about this practice. As a matter of fact, there seems to be a lot of frozen chicken on the market these days. I wonder how many Barbadian consumers have given thought about what was done with chickens held on the chill-counter that were not sold by the “best before date”? Supermarkets need to pay attention to the refrigeration load requirement of their cold storage rooms. The rate at which heat must be removed from a refrigerated space in order to maintain a desired temperature is known as refrigeration load. It is dependent on several factors, including the volume of the space being cooled and the quantity and base temperature of items inside. Cold storage equipment in Supermarkets are only capable of slow freezing: this, therefore means that microbes tolerant to cold conditions have the time needed to grow and proliferate. When chilled chickens are placed on the cold storage, their temperature has to be pulled down from chilled to frozen and this takes time. Over packing the cold storage, affects the refrigeration load and the compressor might not have the rated tonne of refrigerant to do the job. It is best to use sharp freezing (blast freezer) to rapidly pull down the temperature and Supermarkets as a rule do not possess sharp freezing equipment( the processing plants do).
There are many methods available to detect the wholesomeness of refrigerated meats. The ATP (adenosine tri-phosphate) method is one that can be used. All living organisms produce ATP; the greater the ATP content, the greater the microbial load (amount of microbes present). In this case one would have to use an internal/external standard which measures the ATP content of birds which are wholesome and compare the ATP values against those of adulterated birds. Alternatively, one can use the electronic nose (consist of bio-sensors) programmed with the various molecules that are found in putrefying meats,to detect spoiled frozen meat products ( such as diseased birds which have died) and are sold to the public.