Smoke, A Subjective "Flavor"

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Smoke, A Subjective "Flavor"

First, we need to understand what smoke from a fire actually is, and here is a very simple answer from https://www.sciencelearn.org.nz/resourc ... t-is-smoke:

Smoke is a collection of tiny solid, liquid and gas particles. Although smoke can contain hundreds of different chemicals and fumes, visible smoke is mostly carbon (soot), tar, oils and ash.

Smoke occurs when there is incomplete combustion (not enough oxygen to burn the fuel completely). In complete combustion, everything is burned, producing just water and carbon dioxide. When incomplete combustion occurs, not everything is burned. Smoke is a collection of these tiny unburned particles. Each particle is too small to see with your eyes, but when they come together, you see them as smoke.

Smoke in a wood fire

Wood is made up of:
- water
- volatile organic compounds – a compound is volatile if it evaporates (becomes a gas) when it is heated
- carbon
- minerals in the tree’s cells, like calcium, potassium and magnesium (which are non-burnable and become ash).

When you put wood on a hot fire, the smoke you see is the volatile organic compounds (hydrocarbons) evaporating from the wood. They start to evaporate at about 149°C (300°F). If the fire is hot enough, the hydrocarbons will burst into flames. Once they burn, there is no smoke because the hydrocarbons are turned into water and carbon dioxide.

Charcoal

After the fire has been burning for a while, most of the hydrocarbons (gases and smoke particles) have been released, and all that is left is charcoal, which is almost pure carbon with some minerals. The hot charcoal slowly burns with a red glow. There are no flames because charcoal will only produce carbon dioxide, which cannot be burned any further, unlike other vapours. Very little smoke is produced at this stage. The quicker a fire is reduced to glowing charcoal, the hotter it will be and the less smoke it will produce. The carbon combines with oxygen to produce carbon dioxide until all that is left at the end of the fire is the ash – the minerals.

So from this we can ascertain that if a fire is just starting, the material burning is wet, the fire has a lack of oxygen, or there is an absence of flame, etc., the smoke will be heavy, thick, opaque and full of unburned solids. Also, when using charcoal alone, there will not be any smoke "flavor".

If the fire is efficient, has plenty of oxygen, the material is dry, there is flame, etc., there will be very little smoke or unburned solids. The smoke you see from this type of fire, if you see it at all, will be transparent and bluish in color.

Here is an example of each type of smoke coming from an offset cooker. As you can see the "bad" smoke is on the left, and the almost "good" smoke is on the right (even though it is still not burning as cleanly as possible):

No matter the resultant type of smoke coming from a fire, when food is cooked in an environment where the smoke is present, solids in the smoke will be deposited on the surface of the food, giving the food "flavor". This is where the subjective debate of smoke "flavor" comes into play, as every person has their own taste likes and dislikes, which comes directly from the quality of the smoke and the amount of unburned solids deposited on the food during cooking. There is not right or wrong as far as taste is concerned, but there is somewhat of a "standard" for BBQ smokers, which is to achieve the transparent, bluish smoke.

With offset cookers that burn wood, the fire and fire management are completely in the hands of the cook or fire tender. There are many variables in the process, i.e., type of wood, dryness of the wood, is there bark on the wood, ambient temperature, environmental airflow (wind), fire tender's experience, etc. In other words, the cook, or fire tender, has complete control over all of the variables and can achieve either desirable or undesirable smoke, or somewhere in between, to achieve the desired smoke "flavor" on the end product. Yoder Smokers offset cookers were designed to be very efficient and, using the proper procedures, will provide the cleanest burning fire, producing the most transparent, bluish smoke, but, achieving this is entirely in the hands of the cook or fire tender.

Pellet cookers are much different in how the fire is tended, as they are electronically controlled. Some have a "smoke" setting that allows for the creation of the "bad" smoke at the beginning of the cook, which will deposit lots of unburned solids on the food to "flavor" it. Others are super efficient, burning very little fuel (wood pellets), and burning so cleanly that no smoke is present to "flavor" the food. Yoder Smokers pellet cookers were all designed to automically produce the exact smoke output as a Yoder Smokers offset cooker, running a perfectly managed fire. This smoke will be very transparent, and bluish in color, but, unlike in a Yoder Smokers offset, the Yoder Smokers pellet cooker can not be modified to produce "bad" smoke, as the pellet cookers are all run electronically.

So, what if the smoke "flavor" is not subjectively what you are wanting from a Yoder Smokers pellet cooker?

Changing to a different brand, or flavor of pellet might help, but in reality, in blind testing, no one can actually tell what flavor of pellet the food was cooked with. The smell of the wood burning is distinctive, but the resultant "flavor" is not.

If the cook thinks that there is no smoke flavor, which is almost always the case, then this is to be expected, as the cook has been around the cooker and resultant smoke during the cooking process, and has become desensitized to the smoke and ultimately the smoke "flavor" of the food when eating it. We suggest that the cook "freshen up" by taking a shower and changing clothes while the food is resting before eating. This will absolutely make a difference for the smoke "flavor" for the cook. This is why when eating leftover smoked food later, the smoke "flavor" appears to be more pronounced,

If all attempts of getting the subjective desired smoke "flavor" fail, there is another manner of getting the resultant food to have a stronger smoke "flavor", which is to introduce some slightly "bad" smoke into the cooking environment, so more unburned solids are deposited on the surface of the food. There are many products that are called smoke generators that will do this, but we will focus on one of the originals, Todd Johnson's A-Maze-N smoker products: http://www.atbbq.com/a-maze-n-tube-smok ... rator.html

Todd's product works well, but, care must still be taken as to the length of time used in the cooker when cooking, the placement in the cooker, and other concerns. Here is a quote from Todd:

The Yoder is the exception to the rule when it comes to smoke production. I can see guys using a Tube for cold smoking, but not at cooking temps. Good quality pellets is usually the difference between good smoke and bad smoke. I find that some pellets produce more ash and creosote than most other pellets. There are a few other brands that have higher moisture content. They use scrap lumber, store it outside and do not have a dryer to reduce the moisture content. Some of these lesser grade pellets can be upwards of 12%-14% moisture, while the better brands are around 6%-8% moisture.
-Cool or cold smoking in cold weather can produce creosote
- Not enough fresh air can create creosote…Run the fan if there is one, and/or crack the lid
- Not enough air circulation. Placing the Tube Smoke in an area with high heat, but no air for good combustion
- Burning pellets with higher moisture content can produce more creosote

To illustrate an extreme example of what happens with too much "bad" smoke in a cooker, here are a few pictures from a pellet cooker with excessive creosote buildup from using a smoke generator. The black blobs and dark, shiny black coatings are creosote from the unburned solids in "bad" smoke that is built up in the cooker and on the food: