What is Histamine
Histamine is a naturally occurring compound found in many foods, including fish. It is formed by the bacterial breakdown of the amino acid histidine in fish muscle tissue, which occurs during post-harvest handling, processing, and storage.
When fish are not stored properly or handled inappropriately, the bacteria in their tissues can produce high levels of histamine, leading to scombroid poisoning. Scombroid poisoning is a foodborne illness caused by ingesting fish with high levels of histamine. Symptoms of scombroid poisoning include flushing, headache, dizziness, rapid or irregular heartbeat, sweating, nausea, vomiting, abdominal cramps, and diarrhea. In severe cases, scombroid poisoning can lead to anaphylactic shock.
The consumption of fish containing high levels of histamine can be particularly dangerous for individuals with histamine intolerance, as they are unable to properly metabolize the histamine in their bodies, leading to an allergic reaction.
Research has shown that certain types of fish are more prone to high histamine levels than others. For example, fish such as tuna, mackerel, mahi-mahi, anchovy, and herring are known to be high-risk species for scombroid poisoning. On the other hand, fish such as salmon and cod are less likely to contain high levels of histamine.
To prevent scombroid poisoning, it is important to handle and store fish properly. This includes keeping fish at a temperature below 40°F (4°C) and avoiding leaving fish at room temperature for an extended period. Additionally, it is recommended to buy fish from reputable suppliers who follow proper storage and handling procedures.
There have been several documented cases of scombroid poisoning around the world. In 2017, a total of 30 cases of scombroid poisoning were reported in Spain after consuming tuna from a single fish supplier. In 2019, 12 people in Singapore were hospitalized after consuming fish with high histamine levels.
More information on Scombroid Poisoning visit https://www.cdph.ca.gov/Programs/CID/DCDC/Pages/ScombroidFish%20Poisoning.aspx
How to protect consumers from high levels of Histamine
High levels of histamine in fish are typically defined as concentrations above 50 mg/kg. These levels can occur in certain fish species if they are not stored and handled properly after they are caught. When fish are caught, their natural defenses against bacterial spoilage are lost, and bacteria in the fish’s tissue can begin to break down the amino acid histidine into histamine. The longer the fish is stored at temperatures between 40-140°F (4-60°C), the more histamine is produced. This process can be accelerated by poor handling practices, such as leaving the fish exposed to warm temperatures or not properly gutting and cleaning the fish.
To detect high levels of histamine in fish, several analytical methods are available, including high-performance liquid chromatography (HPLC), gas chromatography (GC), and enzyme-linked immunosorbent assay (ELISA). These methods involve extracting the histamine from the fish tissue, separating it from other compounds, and measuring the amount of histamine present.
HPLC is the most commonly used method for histamine detection in fish. It involves injecting a sample of the fish extract into a liquid chromatography system, where the histamine is separated from other compounds using a stationary phase column. The histamine is then detected using a UV-visible light detector, and the amount of histamine present is quantified based on the peak area or height of the chromatogram.
GC is another method used to detect histamine in fish. It involves converting the histamine to a volatile derivative using a chemical reaction, and then separating and detecting the derivative using gas chromatography.
ELISA is a rapid and relatively inexpensive method for detecting histamine in fish. It involves binding a specific antibody to histamine and then measuring the amount of antibody-histamine complex present using a colorimetric or fluorescent detection system. While ELISA is not as accurate or precise as HPLC or GC, it can be useful for screening large numbers of samples quickly and cost-effectively.
In addition to these analytical methods, several rapid tests have been developed that allow fish sellers and consumers to test fish for histamine on-site. These tests involve immersing a small piece of the fish in a test solution and then observing a color change or other visual signal that indicates the presence of histamine.
Overall, the detection of high levels of histamine in fish is important for protecting public health and preventing foodborne illness. Analytical methods such as HPLC, GC, and ELISA are highly sensitive and accurate, and can help ensure that fish are safe for consumption. Rapid on-site tests also provide a useful tool for fish sellers and consumers to quickly and easily check the histamine levels in fish before buying or consuming them.
Next Generation 100% Inspection bioClass®
Hyperspectral imaging is an advanced technology that uses a combination of imaging and spectroscopy to provide detailed information about the chemical composition of a sample. It works by capturing images of a sample at multiple wavelengths, which allows for the identification and quantification of specific compounds based on their unique spectral signature.
Hyperspectral imaging has shown promise as a potential solution for the inspection and detection of histamine in fish. This technology has the ability to rapidly and non-destructively scan large amounts of fish at once, providing a more efficient and cost-effective alternative to traditional methods like HPLC and GC.
One study conducted by researchers at the University of Massachusetts Amherst used hyperspectral imaging to detect and quantify histamine in tuna fish samples. The researchers found that hyperspectral imaging was able to accurately predict the histamine concentration in the samples with a high degree of accuracy, and was able to differentiate between high and low histamine levels.
Another study conducted by researchers at the Korea Food Research Institute used hyperspectral imaging to detect scombroid fish poisoning caused by high histamine levels in mackerel samples. The researchers found that hyperspectral imaging was able to detect histamine levels in the samples with a high degree of accuracy, and was able to differentiate between fresh and spoiled samples.
Overall, hyperspectral imaging has shown great potential as a fast, non-destructive, and accurate method for detecting and quantifying histamine levels in fish. While this technology is still relatively new and expensive, it has the potential to revolutionize the way we inspect and monitor the safety of our food supply. As research in this area continues, it is likely that hyperspectral imaging will become an increasingly important tool for ensuring the safety and quality of our food.