NEW ORLEANS – University of Holy Cross has announced the findings of a research study into the degradation rates and times of local shrimp using a state-of-the-art Certified Qualify Foods reader.
Shrimping, an industry expected to grow to $54.6 billion by 2027, has long been a vital industry for the Gulf Coast. Scientists led by UHC Food Science Program Director Dr. Darryl Holliday and Certified Qualify Foods Co-Founder and Chief Scientific Officer Dr. Keith Cox, tested locally caught frozen shrimp to determine if electricity could be used to measure the degradation of the shrimp. Currently, other than subjective testing, there are no known ways of quickly testing for shrimp degradation.
The research sampled 45 random previously frozen locally caught shrimp that were split into three groups of 15 shrimp. Group one were block peeled shrimp treated with sodium tripolyphosphate, Group two were block peeled untreated shrimp and group three consisted of shatter pack head-on untreated shrimp. Each of the groups were tested over 15 days to determine degradation.
According to researchers, all groups were thawed and showed a measurement of 9.1 on the CQR. After five days on ice, the shrimp gave a reading below 3.5 and began to have a very slight fishy smell. On day seven, the value for all shrimp was below 2.5 and the shrimp had a noticeable odor indicating some spoilage was present. On day nine, the shrimp value was below 1.5 and indicated spoilage beyond what could be safely consumed.
Researchers noted that peeled shrimp fared better because of the sodium bisulfite used on them on the shrimp boats to help prevent enzymatic degradation and bacterial growth. Additionally, the shrimp with the sodium tripolyphosphate were better than the untreated because of the compound binding the water to the shrimp muscle rather than it leaking.
“While testing of this type currently exists for fish, it does not yet exist for shrimp,” said Holliday. “Shrimp have different types of muscle than fish and a high density of collagen – both of which do degrade. Muscle is more affected by freezing than collagen, but it’s still important for us to examine the rate of degradation.”
Researchers say the CQR machine is available for an annual subscription service to an app. The machines are geared towards grocery stores and large purchasers to help them track information on the shelf-life of shrimp stored on ice longer, pulling from sales points sooner or possibly not purchasing the shrimp if degradation is already present.
In the future, researchers hope to test fresh, never frozen shrimp once they receive additional funding.
