Is lobster tomalley safe to eat? (Reasons to avoid)
In this brief guide, we answered the question “Is lobster tomalley safe to eat?”. We also discussed why lobster tomalley may be dangerous and what are the symptoms of intoxication.
Is lobster tomalley safe to eat?
No, consuming lobster tomalley is not recommended. Although lobster meat itself is generally considered safe, the Maine Center for Disease Control & Prevention advises against eating tomalley, which is the green, soft substance found in the lobster’s body cavity. This organ serves as the lobster’s liver and pancreas, and testing has revealed that it can accumulate environmental contaminants. (1)
Why can lobster tomalley be dangerous?
Lobster tomalley poses a potential danger due to lobsters’ propensity to accumulate PSP toxins in their hepatopancreas, also known as tomalley, following the consumption of toxic scallops. The primary source of these toxins in lobsters is the ingestion of bivalve mollusks, particularly scallops like P. magellanicus, which can maintain high toxicity levels year-round in many areas.
Bivalve mollusks are unequivocally the most significant carriers of various shellfish toxins, including paralytic (PSP), diarrhetic (DSP), amnesic (ASP), and neurotoxic (NSP) shellfish poisonings. In regions where lobster tomalley is considered a delicacy and is often used on toast or in soups, this practice could pose a risk of intoxication. (2)
How dangerous is lobster tomalley?
The real health risk is unclear as there is a large variation in the sensitivity to toxins which varies wildly. A person with a high sensitivity to PSP toxins could experience illness or even fatality from a single serving, as the potential toxin intake from the tomalley of a single lobster can reach approximately 150 micrograms.
Cases of illness have been documented after consuming tomalley containing between 144 and 1,660 micrograms of toxins, and fatal poisonings have been reported when estimated consumption ranged from 456 to 12,400 micrograms. Cooking can significantly reduce the toxicity, although it doesn’t eliminate it, and it also reduces the variation in toxicity among individual lobsters.
It’s important to note that low toxin levels were found in the lobster’s stomach, and no toxins were detected in the lobster meat. Therefore, unlike the tomalley, lobster meat is generally considered safe to consume. (2)
What is the nutritional value of lobster tomalley?
Lobster tomalley contains several valuable components. It serves as a protein-rich source, with protein content reaching up to 41% on a dry basis. The amino acid profile of crustacean protein, like that found in lobster, closely resembles red meat protein but has a higher proportion of nonprotein nitrogen, ranging from 10% to 40%.
As a result, crustacean protein is often considered more palatable than meat proteins. In addition, it is important to note that lobster tomalley, a lipid-rich component of the crustacean, boasts an impressive lipid content of up to 24.3%.
These lipids are notably high in polyunsaturated fatty acids (PUFAs) and omega-3 fatty acids. Specifically, tomalley contains 31.3% and 58% of these respective healthy fats. Moreover, lobster lipids also encompass carotenoids and astaxanthin. (3)
What are the symptoms of intoxication?
Paralytic shellfish poisoning (PSP) can manifest with a range of symptoms, including vomiting, abdominal pain, facial and limb numbness, muscle paralysis, impaired speech, a burning or tingling sensation, shortness of breath, loss of coordination, and, in severe cases, respiratory paralysis. If not promptly provided with ventilator support, respiratory paralysis can lead to fatalities.
This toxin is highly potent and has a substantial mortality rate when medical intervention is not available. PSP symptoms can appear as quickly as 2 hours after consuming seafood contaminated with PSP toxins.
PSP is most commonly associated with the consumption of bivalve molluscan shellfish like clams, cockles, mussels, oysters, and scallops, typically from the northeast and northwest coastal regions.
Lobsters are known to accumulate PSP toxins when they feed on toxic bivalve mollusks. These toxins can accumulate in lobster tomalley, posing a risk if harvested from contaminated waters and consumed. (4)
Is it possible to reduce the amount of PSP in tomalley?
Yes, studies have shown that steaming or boiling lobsters can effectively reduce the concentration of PSP in lobster tomalley, with an average decrease of 54%.
The total amount of PSP per tomalley is also reduced, on average, by 70% through these cooking methods. This reduction in PSP levels is associated with the removal of water from the hepatopancreas. When the water content is preserved, there is no reduction in any of the PSP analogs. (5)
In this brief guide, we answered the question “Is lobster tomalley safe to eat?”. We also discussed why lobster tomalley may be dangerous and what are the symptoms of intoxication. Through my studies, I was able to attest that lobster tomalley isn’t safe to eat, as any contaminant present in the lobster will accumulate there. Even though tomalley is considered a delicacy in some places, it poses a health hazard if harvested from contaminated waters.
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Division of Environmental and Community Health.Saltwater Fish & Lobster Tomalley Safe Eating Guidelines. Maine Center for Disease Control & Prevention, Maine Department of Health and Human Services. 2009.
SHUMWAY, Sandra E. Phycotoxin‐related shellfish poisoning: Bivalve molluscs are not the only vectors. Reviews in Fisheries Science, v. 3, n. 1, p. 1-31, 1995.
NGUYEN, Trung T. et al. Lobster processing by-products as valuable bioresource of marine functional ingredients, nutraceuticals, and pharmaceuticals. Bioresources and Bioprocessing, v. 4, p. 1-19, 2017.
Food and Drug Administration (FDA). Fish and Fishery Products Hazards and Controls Guidance – June Edition, U.S. Department of Health and Human Services, 2022.
LAWRENCE, James F.; MAHER, Maurica; WATSON-WRIGHT, Wendy. Effect of cooking on the concentration of toxins associated with paralytic shellfish poison in lobster hepatopancreas. Toxicon, v. 32, n. 1, p. 57-64, 1994.