Shrimp Flakes: Unraveling The Secret Of Their Aroma

Shrimp is a versatile seafood ingredient that is loved by many. However, its smell is not always pleasant, especially when it's not fresh. The characteristic aroma of shrimp comes from an organic compound called trimethylamine, which is present in most seafood. While fresh shrimp should have a mild, slightly salty ocean-like scent, an overpowering fishy smell indicates that enzymes and bacteria have broken down the proteins in the shrimp, producing trimethylamine.

To prevent and remove the fishy odour, several methods can be employed. One simple hack is to rinse the shrimp with cold water and salt, which acts as a sponge to draw out impurities and odours. Another effective approach is to use acidic ingredients like lemon juice, lime juice, vinegar, or buttermilk, which neutralise fishy odours. Additionally, baking soda, known for its odour-absorbing properties, can be used to soak the shrimp for effective odour removal.

It is important to distinguish between fresh and spoiled shrimp. If the shrimp smells like ammonia or has a slimy texture and discolouration, it should be discarded as it may cause food poisoning. Proper storage is crucial to maintaining shrimp's freshness; it should be refrigerated and used within a few days or frozen for extended periods.

While shrimp may not be the most fragrant ingredient in your kitchen, these tips can help you manage its odour and ensure you enjoy delicious shrimp dishes without any unpleasant smells.

Shrimp should smell like the ocean, not fish

Fresh shrimp should have a mild, slightly salty aroma of the sea. If your shrimp smells fishy, it may be due to enzymes and bacteria breaking down the proteins in the shrimp and producing trimethylamine (TMA), the compound responsible for the pungent odour.

To prevent this from happening, it's important to practise safe food handling. When defrosting shrimp, always do so in the fridge or under running cool water. Never leave shrimp out on the counter to defrost, as this can cause bacteria to grow and produce that fishy smell.

Additionally, shrimp that has been frozen and then thawed may develop a fishy odour if it has not been properly shipped or stored. If your shrimp has been thawed and refrozen, it can affect its quality and taste, leading to a stronger odour.

To avoid this issue, purchase shrimp that has been frozen only once, and practise safe defrosting methods as mentioned above.

If you're unsure whether your shrimp is still good, it's best to err on the side of caution and throw it out. Other signs of spoiled shrimp include a slimy texture, discolouration, and a strong ammonia smell.

When cooking shrimp, a simple pan fry is sufficient. There is no need to boil them first, as this can be overkill and lead to overcooking, resulting in a rubbery texture and stronger fishy smell.

In summary, shrimp should smell like the ocean, with a mild, briny scent. A strong fishy odour is often an indication that your shrimp has gone bad or has not been handled or stored properly. To prevent this, practise safe food handling and storage methods, and cook your shrimp properly to ensure the best taste and texture.

Shrimp spoilage indicated by ammonia smell

Shrimp spoilage is indicated by an ammonia smell. This is a sign that the shrimp has gone bad and is no longer safe to eat.

Fresh shrimp should have a mild, slightly salty aroma of the sea. However, when enzymes and bacteria break down the proteins in the shrimp, they produce trimethylamine (TMA), the compound responsible for a pungent, fishy odour. This odour can be neutralised using a few simple hacks, such as a salt rinse, an acidic marinade, or a baking soda soak.

If the shrimp smells like ammonia, it is likely that it has spoiled and should be discarded. This ammonia odour is a result of spoilage and is not to be confused with the natural iodine flavour of shrimp, which comes from the organisms they eat.

It is worth noting that shrimp may also have an iodine taste or smell, which is distinct from the ammonia smell of spoilage. Additionally, heterocyclic compounds, including pyrazines, thiazolines, and thiazoles, are major contributors to the characteristic aroma of whole roasted shrimp.

To prevent shrimp spoilage, it is recommended to cook and eat shrimp on the day of purchase and to avoid buying pre-cooked shrimp. Proper storage is also key—keep shrimp in the coldest part of the refrigerator and use within a day or two, or freeze to maintain freshness.

Trimethylamine: the compound behind shrimp's ocean smell

Shrimp is known for its distinct, briny aroma, often likened to the ocean. This characteristic smell is due to the presence of trimethylamine, an organic compound found in most seafood. While some may find the scent unpleasant, it is a tell-tale sign of fresh and unspoiled shrimp.

Trimethylamine is an organic compound with the chemical formula N(CH3)3, consisting of a nitrogen atom bonded to three methyl groups. It is responsible for the ocean-like or fishy smell associated with shrimp and other seafood.

The amount of trimethylamine in shrimp increases over time, especially when stored raw, leading to a stronger fishy odour. This is because, when seafood dies, bacteria start to break down its proteins, producing trimethylamine. Therefore, the longer shrimp is stored, the higher the concentration of trimethylamine, and the more pronounced the fishy smell becomes.

To prevent shrimp from smelling overly fishy, it is important to practise proper storage methods. Rinsing shrimp with tap water or treating it with acidic ingredients like lemon juice or vinegar can help slow down the growth of bacteria and the production of trimethylamine. Additionally, removing the shell and deveining the shrimp can also reduce its smell.

While a mild ocean-like smell is normal for fresh shrimp, a strong fishy or ammonia odour indicates spoilage. Other signs of bad shrimp include discolouration, a slimy texture, and black spots on the shrimp's flesh. If you notice any of these signs, it is best to discard the shrimp to avoid potential food poisoning.

In Conclusion

Trimethylamine is the key compound that gives shrimp its characteristic ocean-like smell. While this scent is generally pleasant and indicative of fresh shrimp, excessive amounts can be off-putting. Proper storage and handling techniques can help control the growth of bacteria and maintain shrimp's desirable aroma.

Neutralising shrimp's fishy smell

Shrimp should have a mild, slightly salty aroma of the sea. However, when enzymes and bacteria break down the proteins in the shrimp, they produce trimethylamine (TMA), which gives off a pungent, fishy odour. Here are some methods to neutralise this smell:

The Salt Rinse

Sprinkle your shrimp with salt (with or without the shell on) and gently massage it in for a minute. Rinse the shrimp with cold water and repeat this process 2-3 times for maximum odour removal. Salt draws out impurities and odours from the shrimp like a sponge.

Acidic Marinades

Acid ingredients like lemon juice, lime juice, vinegar, or buttermilk can neutralise fishy odours. Marinate your shrimp in a simple marinade with any of these ingredients and your choice of herbs and spices for 15-30 minutes before cooking.

Baking Soda Soak

Baking soda is a natural odour absorber. Mix 1 tablespoon of baking soda with 2 cups of cold water and soak your shrimp for 15-20 minutes. Rinse thoroughly before cooking, and be careful not to over-soak as it can affect the texture.

Milk Soak

If you still notice a slight fishy odour after the previous steps, try soaking your shrimp in milk for 15-20 minutes. The proteins in milk bind to the TMA, effectively removing it.

Herb & Spice Infusion

Herbs and spices not only add flavour to your shrimp but can also help mask any lingering odours. Toss a few sprigs of thyme, rosemary, or bay leaves into the cooking water, or add a pinch of your favourite spice blend.

Proper Storage

To avoid shrimp developing a fishy smell in the first place, ensure proper storage. Keep shrimp in the coldest part of your refrigerator (usually the back) and use them within a day or two. If you’re not planning on cooking them right away, freezing is the best option for maintaining freshness.

How to tell if shrimp has gone bad

Shrimp is a popular seafood choice, but it's important to ensure it's fresh to avoid foodborne illnesses. Here's how to tell if your shrimp has gone bad:

Colour

Raw, fresh shrimp should appear grey, white, or even translucent. If you notice any discolouration or spots on your shrimp, it's best to toss it. On the other hand, cooked shrimp should be a bright pink colour. Faded or grey cooked shrimp is a sign that it has gone bad.

Smell

Fresh shrimp should have a mild, slightly salty aroma of the sea. If your shrimp has a sour, ammonia-like smell, it's time to throw it out. Good shrimp may also have a lingering salty aroma or a very subtle "fishy" smell.

Texture

If your shrimp feels slimy or is covered in a thin film, it has likely gone bad and should be discarded.

Storage Time

Raw shrimp lasts 1 to 2 days in the refrigerator, while cooked shrimp lasts for 3 to 4 days. If your shrimp has been left out for more than 2 hours at room temperature (or 1 hour if the temperature is above 90°F), it needs to be thrown away.

In the freezer, shrimp has an indefinite shelf life but will lose flavour and quality after about 3 months.

Other Signs

If your shrimp has an overpowering "fishy" smell, it could be due to enzymes and bacteria breaking down the proteins in the shrimp and producing trimethylamine (TMA). This compound is responsible for the pungent odour. If you're unsure, it's best to discard the shrimp, especially if it has a slimy texture or a strong ammonia smell, which indicates spoilage.

Frequently asked questions