1. The functions of smoking
A. It endows the product with a unique smoked flavor. The components of smoke, including phenols, alcohols, organic acids, carbonyl compounds, and the flavor substances formed by their reactions with the components of the meat, jointly constitute the smoked flavor.
B. It forms a unique color (tea brown): This color is the result of browning reactions or Maillard reactions between amino compounds on the product's surface and carboxyl compounds in the smoke components.
C. It kills bacteria and has preservative effects: Aldehydes, acids, and phenols in the smoke all have bactericidal capabilities, especially the derivatives of phenols, which have stronger bactericidal abilities.
D. It has antioxidant properties: Phenols and their derivatives have strong antioxidant effects, particularly against the rancidity of fats.
E. It dehydrates and dries the product for easier storage. The lower the temperature in the smoking chamber, the lighter the product's color; the higher the humidity, the darker the color. At lower temperatures, the color is light brown, while at higher temperatures, it becomes dark brown.
2. Factors Affecting the Penetration of Smoked Components
The components of smoke; the concentration of smoke; the temperature and humidity of the smoking chamber; the tissue structure of the product; the ratio of fat to muscle; the moisture content of the product; the material of the product's casing; the smoking method; the smoking time. Smoke is a complex aerosol formed by a large number of liquid-phase dispersions and a small amount of solid-phase dispersions dispersed in the gas phase (air). The movement of smoke particles: Brownian motion, thermophoresis, gravitational force, and air flow in the smoking chamber.
3. Smoke-producing Materials and Smoke Generation Temperature
The smoking material and smoking temperature are the decisive factors for the composition of the smoke. Hard broadleaf tree woods with less resin are commonly used as smoking materials, such as beech, poplar, walnut, birch, elm, etc., while coniferous woods like pine, fir, and cypress are not used (they produce black smoke and a bitter taste). For the same wood, different smoking temperatures result in different smoke components and their respective contents. At 200℃ - 260℃, smoking begins; at 260℃ - 310℃, pyrolysis liquid and some tar are produced; above 310℃, lignin pyrolysis generates phenols and their derivatives. Studies have shown that burning at 400℃ is most suitable for the formation of the highest amount of phenols, but at this temperature, it is favorable for the formation of benzo(a)pyrene and other polycyclic aromatic hydrocarbons. In practice, the best combustion temperature is controlled at around 343℃.
4. Smoking Methods
A Cold smoking: 15℃ - 25℃ dry sausage, in winter; B Warm smoking: 30℃ - 50℃, genuine Western-style products, bacon. The smoking time is usually 1 - 2 days; C Hot smoking: 50℃ - 80℃, typically 60℃ - 65℃. This is the method we use most frequently. From the perspectives of time, color, and safety; D Liquid smoking: This is a method that uses liquid smoke substitutes for traditional smoking. Its advantages include no need for smoke, short processing time, stable composition, and less carcinogenic substances. Disadvantages: Complicated operation and inferior taste. The quality of the liquid smoke is crucial. E Roast smoking: 90℃ - 120℃, using charcoal fire in a closed environment, and opening only after complete cooling. The products smoked in this way have bright colors that do not fade easily, full flavor, and good texture. However, it generates more carcinogenic substances and has a lower yield.
5. Smoking and steaming sequence
The sequence of smoking and boiling varies among different manufacturers. In China, due to poor hygiene of raw materials and lax hygiene control in each production stage, the semi-finished products put into the oven have a high bacterial count. The commonly used baking temperature is generally 60℃-70℃, and the internal temperature of the product usually does not exceed 50℃. Therefore, the bacterial count of the semi-finished product after baking is very high. If it is directly smoked at 60℃-65℃ and then boiled, the product quality will decline. Of course, boiling first and then smoking also has its disadvantages: it is troublesome and wastes energy. After boiling, the moisture in the oven should be removed, and the product should be baked for a short time before smoking. If it is a water bath boiling, there will be an extra transfer of the product from the oven to the outside. The product color after direct smoking after baking is better than the latter. Smoking first and then boiling can also cause some loss of smoking components.
6. Precautions for Smoking
A. During smoking, ensure the surface of the product is clean; B. Do not hang too many or too few products in the smoking room; C. Dry the products appropriately before smoking; D. The temperature in the smoking oven should not rise or fall too rapidly. If the method of smoking followed by boiling is adopted, the products should be boiled immediately after smoking; E. No flames should appear during smoking; F. The smoking temperature and time should be determined based on the type of product and process requirements; G. Keep good records.
A. It endows the product with a unique smoked flavor. The components of smoke, including phenols, alcohols, organic acids, carbonyl compounds, and the flavor substances formed by their reactions with the components of the meat, jointly constitute the smoked flavor.
B. It forms a unique color (tea brown): This color is the result of browning reactions or Maillard reactions between amino compounds on the product's surface and carboxyl compounds in the smoke components.
C. It kills bacteria and has preservative effects: Aldehydes, acids, and phenols in the smoke all have bactericidal capabilities, especially the derivatives of phenols, which have stronger bactericidal abilities.
D. It has antioxidant properties: Phenols and their derivatives have strong antioxidant effects, particularly against the rancidity of fats.
E. It dehydrates and dries the product for easier storage. The lower the temperature in the smoking chamber, the lighter the product's color; the higher the humidity, the darker the color. At lower temperatures, the color is light brown, while at higher temperatures, it becomes dark brown.
2. Factors Affecting the Penetration of Smoked Components
The components of smoke; the concentration of smoke; the temperature and humidity of the smoking chamber; the tissue structure of the product; the ratio of fat to muscle; the moisture content of the product; the material of the product's casing; the smoking method; the smoking time. Smoke is a complex aerosol formed by a large number of liquid-phase dispersions and a small amount of solid-phase dispersions dispersed in the gas phase (air). The movement of smoke particles: Brownian motion, thermophoresis, gravitational force, and air flow in the smoking chamber.
3. Smoke-producing Materials and Smoke Generation Temperature
The smoking material and smoking temperature are the decisive factors for the composition of the smoke. Hard broadleaf tree woods with less resin are commonly used as smoking materials, such as beech, poplar, walnut, birch, elm, etc., while coniferous woods like pine, fir, and cypress are not used (they produce black smoke and a bitter taste). For the same wood, different smoking temperatures result in different smoke components and their respective contents. At 200℃ - 260℃, smoking begins; at 260℃ - 310℃, pyrolysis liquid and some tar are produced; above 310℃, lignin pyrolysis generates phenols and their derivatives. Studies have shown that burning at 400℃ is most suitable for the formation of the highest amount of phenols, but at this temperature, it is favorable for the formation of benzo(a)pyrene and other polycyclic aromatic hydrocarbons. In practice, the best combustion temperature is controlled at around 343℃.
4. Smoking Methods
A Cold smoking: 15℃ - 25℃ dry sausage, in winter; B Warm smoking: 30℃ - 50℃, genuine Western-style products, bacon. The smoking time is usually 1 - 2 days; C Hot smoking: 50℃ - 80℃, typically 60℃ - 65℃. This is the method we use most frequently. From the perspectives of time, color, and safety; D Liquid smoking: This is a method that uses liquid smoke substitutes for traditional smoking. Its advantages include no need for smoke, short processing time, stable composition, and less carcinogenic substances. Disadvantages: Complicated operation and inferior taste. The quality of the liquid smoke is crucial. E Roast smoking: 90℃ - 120℃, using charcoal fire in a closed environment, and opening only after complete cooling. The products smoked in this way have bright colors that do not fade easily, full flavor, and good texture. However, it generates more carcinogenic substances and has a lower yield.
5. Smoking and steaming sequence
The sequence of smoking and boiling varies among different manufacturers. In China, due to poor hygiene of raw materials and lax hygiene control in each production stage, the semi-finished products put into the oven have a high bacterial count. The commonly used baking temperature is generally 60℃-70℃, and the internal temperature of the product usually does not exceed 50℃. Therefore, the bacterial count of the semi-finished product after baking is very high. If it is directly smoked at 60℃-65℃ and then boiled, the product quality will decline. Of course, boiling first and then smoking also has its disadvantages: it is troublesome and wastes energy. After boiling, the moisture in the oven should be removed, and the product should be baked for a short time before smoking. If it is a water bath boiling, there will be an extra transfer of the product from the oven to the outside. The product color after direct smoking after baking is better than the latter. Smoking first and then boiling can also cause some loss of smoking components.
6. Precautions for Smoking
A. During smoking, ensure the surface of the product is clean; B. Do not hang too many or too few products in the smoking room; C. Dry the products appropriately before smoking; D. The temperature in the smoking oven should not rise or fall too rapidly. If the method of smoking followed by boiling is adopted, the products should be boiled immediately after smoking; E. No flames should appear during smoking; F. The smoking temperature and time should be determined based on the type of product and process requirements; G. Keep good records.
