With today’ s economy and tuna prices at their highest, it is important that we maximize every aspect of processing to maintain, low cost, high recoveries, high yields, and high quality. Of course the raw tuna is the highest cost factor that goes into the finished product and would be the key issue for maximizing, but all the other different cost factors are no exception for full attention. Over the years, I have worked in tuna canneries all over the world and have learned and noted the best techniques and methods to process tuna. I was also fortunate to have conducted several years of intense research and process development work towards improving tuna processing, through high tech equipment, methodology, technique, and strict process control by management. Although I have seen some very nice and efficient tuna processing plants, I have yet to see the ultimate tuna cannery that utlizes the best of the best of all the attributes needed for the perfect tuna operation. Although this may never be done, we can only learn and try to maximize and improve what we have already.

It takes several different processing steps to complete a finished tuna product whether it be canned, loins, or pouch. I can truly say that temperature is key factor for optimum quality, yields, and recovery. It is the starting point for all processing. This is true with all seafoods but more so with tuna because it requires much hand labor and longer delay times between processing steps can be very critical. In order to monitor fish temperature, it is very important that we know the correct way to take the temperature of fish. The most common temperature indicator is referred to the >backbone temperature@. If this is not done consistently and correctly, the temperature differences can be as high as 10-20F. This would definitely result in decomposition and over/under processing. Believe it or not so many tuna canneries that I have worked at or visited did not take temperatures correctly and some used thermometers that were never calibrated. To start with, your thermometer must be accurate whether it is a digital or dial type and should be calibrated at the least daily if not more, depending on usage. This can easily be done by using a beaker of ice water, and boiling water. Both the high and low temperatures must be checked.

Once you have an accurate thermometer, you can now take the temperature. I feel that the most correct and consistent way to take the backbone temperature is to penetrate the fish near the dorsal fin area until you hit the actual backbone, then pull out slightly and then go beyond the backbone no more than a few centimeters but keeping the probe against the backbone. This allows measurement of the fish at the largest point where the temperature will be the lowest. If this is done with all fish, then you will have accurate and consistent temperature monitoring. Good temperature monitoring will make each processing step more consistent.

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