Progress 07/01/23 to 06/30/24

Outputs
Target Audience:The target audience for this project is still fisheries and providers of fish products. Our primary focus during this reporting period has been on research and development, so we have not made specific outreach efforts. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?In the next reporting period, we plan to accomplish all 3 of our research objectives. Our first objective is functionally complete; we can detect histamine at concentrations far below the levels the FDA considers hazardous. To complete our second objective, we will modify our platform to better eliminate interference from the accidental detection of other compounds. We will ensure that any modifications we make retain our ability to detect histamine at low concentrations. To complete our third objective, we will purchase a range of fish products that are known to cause scombroid poisoning, and we will test our platform against them under a range of conditions (different storage times, temperatures, etc.). We will use the results of these tests to determine any modifications that are required before bringing the product to market. Once we have sufficient data in fish products, we will also begin reaching out to fisheries and fish manufacturers, either through our network, conferences and shows, or direct outreach. We will offer demonstrations and comparisons to their current methodologies to advocate for the advantages of our platform.

Impacts
What was accomplished under these goals? Scombroid poisoning is one of the most common sources of food-borne illness, and it is often caused by improper storage and transport of fish products at temperatures that promote bacterial growth and fish spoilage. The microscopic cause of scombroid poisoning is ingestion of high levels of histamine. This project's goal is to provide a fast, simple, cost-effective method of detecting histamine in fish products before they reach consumers. This will both prevent illness and avoid the manufacturer costs of product recalls and testing using more expensive and cumbersome methods. The threshold for safe histamine levels in food set by the USDA is 50 ppm (mg per kg of food). Our first objective was to detect histamine at this level using our custom detection platform; to achieve this, we have used our platform for the detection of histamine in a range of solvents of different compositions, and used different analytical chemistry techniques to determine the detectable level of histamine in the product. We have succeeded in this objective, and are able to detect histamine at concentrations as low as 10 ppm, which indicates that even after diluting and processing a fish sample for our test, we will still be able to detect whether the original sample had dangerous levels of histamine. In addition, the liquid we use to detect histamine is safe, stable, and inexpensive. The measurement technique we use provides electrical data, which can straightforwardly be translated into a digital readout that will provide fish manufacturers with easy-to-understand information about the safety of their product. The second objective was to ensure that our detection method did not accidentally detect other compounds in fish molecules. To achieve this, we place special coatings on our detection platform that are intended to filter out other compounds and only allow the detection of histamine. While this objective is still in progress, we have largely been successful; the most prominent compounds in scombroid-causing fish are amino acids and fats. Our detection method shows high selectivity for histamine against the fats present in fish as well as all amino acids, including histidine, which is the source of histamine. This selectivity against histidine indicates that our platform will be effective at distinguishing fresh fish from spoiled fish. Our current efforts are on maintaining selectivity against the biogenic amines, which are compounds in fish whose presence indicates spoilage, such as spermine, spermidine, putrescine, and cadaverine. When we've established selectivity over these compounds, we will be in a strong position to begin testing on fish products.

Publications