The Difference Between Hot Smoked & Cold Smoked Fish 3 February 2016
The Difference Between Hot Smoked & Cold Smoked Fish
Most of us probably don’t pay much attention to how our fish is prepared; fish is fish and that’s that, but there’s actually a lot more to it. Here at Trafalgar Smokehouse we have built up a reputation over the last 5 years for producing high quality smoked fish products including hot smoked trout, smoked peppered mackerel and organic smoked salmon. With many people still unsure what hot and cold smoking entails, we hope to shed a little light on different hot and cold smoking techniques and the different flavours and textures they can give. We’ll also share some best practice steps for preparing and cooking fish using these two techniques.
What is Hot & Cold Smoking?
Smoking is one of the oldest methods of preserving fish, existing long before the days of the fridge freezer. Our fishing ancestors came up with the method of stopping their fish from spoiling using a combination of salt and smoke. Modern technology has largely made this method of preservation unnecessary but it remains a popular technique for adding flavour and texture to fish.
Put simply, cold smoking fish is the process of flavouring fish by curing it with smoke. This is done by placing it in an unheated chamber and pumping smoke through the chamber for a period of around 12- 48 hours. The longer you smoke the fish for the more intense the smoke flavour will be. Cold smoked fish will still need cooking after the smoking process, with one exception being cold smoked salmon, which can be eaten raw.
Hot smoking fish is the process of flavouring and cooking the fish simultaneously, both curing and smoking. This is achieved by placing the fish directly in a kiln alongside burning wood chips for a period of 40 minutes to 2 hours, depending on the size of the fish. If you are smoking mackerel to create smoked peppered mackerel, this will need less time to smoke compared to a large salmon. Ensure that the fish is completely cooked through before eating.
Hot Smoked vs. Cold Smoked Fish
Both methods of smoking can produce marked differences in taste and texture. The main difference between the two smoking methods is the temperature at which the fish is smoked. There are plenty of disputes regarding what is the optimum temperature for achieving the best results. According to many, the perfect cold smoked fish should not exceed 77 degrees Fahrenheit (25°C). At temperatures below 140 degrees Fahrenheit (60°C) bacteria breeds fast, so hot smoking temperatures should be around 158-176 degrees Fahrenheit (70-80°C) though some argue this should be higher. Smoking the fish at to high of a temperature will make it dry and chewy. For the best results when hot or cold smoking, it is preferred to use a rich, oily or fattier fish like salmon or trout, as more of the smoke flavour will be absorbed.
Which Smoking Method is the Best?
Different people will have different opinions on what is the best smoking method because it’s largely down to personal taste.
When done right, hot smoked fish, salmon in particular, should have a delicate, creamy, almost mousse-like consistency. However some people have experienced organic hot smoked salmon to be dry and chewy, which can be caused by excessive smoking. Cold smoked salmon has a deep smoky flavour, however this has been described as ‘slimy’ by some. Cold smoked salmon is commonly eaten with cream cheese, herbs or scrambled eggs.
The Importance of Curing Hot and Cold Smoked Fish
It is very important that before smoking your fish you cure it in either a salt water brine or a dry salt cure. This process of preparing the fish is required for both hot and cold smoking techniques and draws out excess water from the fish, leaving you with a firmer and more flavoursome fish ready to be smoked. This curing process is often referred to as osmosis, as the salt curing inhibits the growth of microorganisms by drawing water out of microbial cells.
Basic water brine is made up of water and equal quantities of sugar and salt. The most popular salt to use is kosher salt, which has a much larger grain size than table salt. The salt and sugar in the brine do more than just flavor the fish. They are part of a delicate balance between removing and retaining moisture in the flesh of the fish.
The salt plays the important part of breaking down the proteins, removing excess water, preserving the fish and enhancing the flavours. The sugar in the mixture adds to the flavour of the smoked fish as well as retaining water to keep it as fresh as possible.
A basic measure of salt water brine is 2 pints of cold water; 4oz kosher salt and 4oz brown sugar. To add to the flavours, you can also add fresh herbs, spices, hot peppers, garlic, onions, wine, soy sauce or just about anything you want to add extra flavours to your smoked fish.
A dry salt cure works in exactly the same way to preserve and add flavour to the fish, whilst removing excess water. For a basic dry salt cure, simply cover the fish in kosher salt and brown sugar. A typical measure is 100g salt and 100g sugar per 1 kilogram of fish. Just like the brine you can choose to add additional ingredients to the cure to add to the flavour.
Steps For Curing Fish
- Place the fish in a metallic bowl and cover with either a salt water brine or a dry salt cure to allow for the curing process to begin. Ensure the skin of the fish in left on, on one side, as this will lock in the flavours.
- Cover the bowl and place something heavy on top to keep the moisture in and place in the refrigerator.
- Fish pieces one inch thick or more should be left to cure for 8-12 hours. For thinner pieces 6-8 hours is sufficient.
- After the fish has been left to cure, remove from the mixture and rinse well under cold water. Pat the fish dry with a tea towel or tissue.
- Place the fish back in the refrigerator uncovered for another 12 hours, or until ‘tacky’. This process is called pellicle, where a tacky skin develops, giving the smoke something to stick to and absorb more easily.
Steps For Cold Smoking Fish
Once the fish has been cured and has developed a tacky skin, it is ready to be cold smoked.
- Use a smoker that has a separate chamber for the smoke and a separate chamber in which the fish is placed, such as the ones from Bradley. Be careful when choosing a smoker as many will run too hot for cold smoking. You can always build your own smoker here.
- Use wood chips such as hickory, apple and cherry as these are the most popular for adding a great smoking flavour.
- If your smoker has a hot element, make sure that it is switched to cold smoking.
- Place the fish with enough space between them to allow for the smoke to be pumped through into the chamber and cover the fish evenly.
- Smoke for 12-48 hours depending on the size of the fish.
- Make sure that the smoker is no hotter than 25°C. For a more smoky taste you can add more wood chips half way through.
- The fish should feel firm after the smoking process.
- For best results, leave the fish to cool to 10°C within 3 hours.
- Chill until ready to serve.
- Salmon is the only fish that you can eat after cold smoking; all other fish will need to be cooked.
Steps For Hot Smoking Fish
Once the fish has been cured and has developed a tacky skin, it is ready to be hot smoked.
- Use a hot smoker or smoke your fish. A smoke with a clamp or vacuum seal is ideal for keeping the smoke locked in.
- Woods chips similar to that used for cold smoking can be used for hot smoking for an intense smoky flavour. Wood chips like hickory and alder are popular.
- Place the fish skin side down on a oiled grill rack above the smoky wood chips to allow for the smoke to cover the fish, smoking it and cooking it simultaneously.
- Smoke the fish for 40 minutes to 2 hours depending on the size.
- Ensure that the smoker remains between 70-80°C to make sure the fish cooks through but also stays tender.
- For a more smoky taste you can add more wood chips half way through.
- Once the fish is smoked it is ready to be served and enjoyed.