Smoked Herring Fish Manufacturing; Advantages and Disadvantages


This year, Sham el-Nessim coincides with the holy month of Ramadan; have you ever tried eating herring fish on fasting days before? I do not advise you to do so, especially in Sohour; salts generally cause thirst and high blood pressure. Have you asked though what are smoked herring fish and how they are prepared?

The process of smoking fish aims to preserve and increase its shelf life. The fish also acquire a distinctive taste and flavor, besides its golden color. The process depends on the smoke rising from the incomplete burning process of some types of timber or sawdust that are hydrated with water—at least thirty minutes before smoking the fish—to increase the smoke and reduce combustion.

This process has been used for thousands of years to preserve fish; in France, headless smoked fish were found in Stone Age cemeteries. To avoid the risk of microbial growth in fish, the processes of salting and drying are applied before smoking to preserve the fish safely for a longer time. Famously smoked fish types are herring, also known as Renga, and sometimes sardines and eels.

Smoking Methods

1. The Traditional Method

After fish are salted and dried, they are hung in chambers, known as smoking chambers. At the bottom of these chambers, there is a place equipped for burning wood, and the fish are exposed to the rising smoke for several hours. The flavor and color of fish vary according to the duration they are exposed to smoke. Smoking can be cold, where smoke is at a low temperature, or hot, where high heat is used to cook the fish.

Smoking White Fish in the traditional Grimsby Style

2. Smoking by Liquid Smoke

It is a simpler method that reduces the number of harmful substances from smoke. When the wood is not completely burned during combustion, the smoke is passed over water to dissolve it and then extracted in a liquid form. During this method, the harmful hydrocarbons from smoke are eliminated. Dealing with fish becomes easier afterward, as they are immersed in, sprayed, mixed with, or injected by the liquid smoke.

3. Smoke Preservative Effect

Smoke contains more than 300 chemical compounds, some of which have a preservative effect; some act as antioxidants that prevent rancidity. Some smoke compounds, such as phenols, aldehydes, organic acids, and gum, kill or retard the growth of harmful microbes in meat and fish, especially E. coli, Staphylococcus aureus, germs of Clostridium botulinum, among others. Smoke compounds do not prevent the growth of fungi; that is why, after salting, fish are submerged in 1% of ascorbic acid solution.

Are Smoked Fish Harmful?

Overeating smoked food is not recommended, as they contain carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs), but no need to worry. The non-excessive consumption of smoked food means a low concentration of these harmful compounds, especially since our consumption is much less than in other countries. For example, the Japanese use the smoking technique in preserving and manufacturing several food types, including cheese, fish, and meat. Likewise, high blood pressure patients should be careful when eating salted fish, even in small amounts or unsalted; harmful bacteria may still grow in it.

Can this process be done at home?

Yes, and it will be fun. Some stores sell the needed tools to apply this cooking technique at home. After salting, the process takes hours, during which you can have a drink; however, you have to be careful and learn the correct steps. Not enough salting or improper smoking can mean the growth of microbes in the fish and deterioration.

References (1) (2) (3)

Top image: Smoked Herring Fish. Source:

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