Radical Waters goes Fishing

If only it were as simple as straight from the sea and into the frying pan. However, the truth is its not quite so seamless. In today’s fishing industry, a major hindrance to product quality is the risk of unforeseen spoilage, closely followed by costly product returns. Processors aim to avoid this at all costs through extensive quality efforts which go on behind the scenes, including careful monitoring of their processing regime.Through these initiatives potential quality defects are identified and addressed. 

Once caught out at sea, microbes on fresh fish are picked up at various processing points starting with the fishing vessel itself. Following gutting, fresh fish are placed on ice.keeping the raw product as cool as possible is critical, even though it has been shown that spoilage bacteria are capable of sustained growth at temperatures less that 1C. If fish are not kept below freezing point before further processing, the potential for microbial contamination increases throughout the entire process. While the inner muscles of a health fish are clean, microbes are found generally in three distinct places: the outer slime, gills and the intestines. early stages of organoleptic (texture & smell) may well be noted by examining the gills for the presence of off-odours. In addition, should the internal organs not be removed straight away, intestinal bacteria soon make their way through the intestinal walls and into the flesh.


Among the various quality tests undertaken during processing, food scientists need to monitor the Total Volatile Nitrogen (TVN) levels in fish. Although nitrogen based compounds are common in fish, they may become unstable during decomposition. “Excessive handling and a breakdown in the cold chain all contribute to an elevation in the levels of TVN commonly found in fish. Once TVN is broken down it is predisposed to forming Histamine, a common food allergen.” Says Dr. Robin Kirkpatrick, Technical Director at Radical Waters. It has been found that some fish plants may treat high TVN counts with a rehabilitation remedy in order to ensure that these counts remain within a legally acceptable level. From a legislative point of view these kinds of rehabilitation additives are becoming progressively more regulated within the industry.


Once a batch of fresh fish has spoiled the product may need to be quarantined for extended periods, incurring a waste of high-value packaging material as well as taking up costly storage space and valuable production time. Furthermore such products which have undergone rehabilitation treatments are more commonly reworked into lower grade products at substantially less value commercial products such as animal feed. In another scenario, and assuming optimal cold chain conditions, once transported to shore, fish plants begin processing and packaging in preparation for dispatch. Fished are sorted, weighed, rinsed and filleted. The end products come in array of shapes and sizes – solely dependent on the type of value-ads which are determined by the customer. One of the more common procedures to add value to raw fish products is to batter and crumb the fillets which run a conveyor belt system and surplus run-off is then recirculated from a sump located under the batter sprayers. Batter batches are changed on an intermittent basis which is largely at the discretion of the operators. There is no escaping the importance that fish plants are required to comply with strict microbial quality specifications. This is largely due to the health and product risks associated with contaminated batter applied to the crumb coated fillets.


Aside from having hygiene device installations in the South African fishing industry, Radical Waters recently conducted  trials in June 2009 at three international fish processing facilities. The results proved Radical Waters’ electro-chemically activated (ECA) Anolyte solution to be a highly effective anti-microbial partner for any fish processor. ECA solutions have been used for: ice manufacture, treatment of fresh fish prior to processing, treatment of product post-filleting, treatment of fillet conveyors, preparation and decontamination of batter and the preparation of fresh fillet portions. “A trial was conducted to include ECA  into packaging ice, the results provided an overall reduction in microbial counts on freshly gutted fish. It was further noted that through the treatment of fresh fish with ECA based ice and baths, the overall yield of the fresh product increased by 1%. This translates into an increase in final product yield of up to 10%.” Reports Kirkpatrick. “Included in these trials the efficacy of ECA’s Anolyte solution was tested as a suitable substitute for a commonly used TVN rehabilitation additive. The results proved highly favourable, and the treated product fell well within the acceptable levels of 20mg TVN per 100gm, without the questionable presence of hazardous residues and taints,” he concludes.