Outside air temp affect on cook times

padlin00

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Has anyone else noticed the cook times change with the outside air temp? My rib cooks in this 90 degree weather are roughly an hour faster then in the winter. I know the actual cut of meat can have some affect, but this is to consistent to not be the air temp. I do keep my meat in the fridge right up till it goes on the smoker so the meats temp should be the same. I kept notes for a while when I first started smoking so I could gauge timing for dinner and such, took me 2 years to figure out I need to adjust for the weather. Some folks are slow learners.
 
Weather can affect all cooks, regardless of what kind of smoker it is.

You’d be better off setting your meat out for a bit before smoking it.
 
padlin00, I have seen posts that confirm what you are saying, especially in the colder regions when it is below freezing. I think that’s why RecTeq sells a blanket for some of their smokers. I live in Southern California so I don’t really have first hand experience that I can talk about so I just blame it on different cuts of meat and/or fat levels in the proteins I cook. I also read complaints about the higher humidity level areas and those at higher altitudes noticing differences. I guess if you notice the cook time and the pellet consumption levels are significantly different, that could be one of the X-factors to consider. Have a great day and cook.
 
I’ve read that too, but I like to put the rub on and let it sweat. Moisture absorbs smoke readily. I certainly wouldn’t recommend letting meat sit out until it reaches room temp, but 20-30 to 60 minutes seems to work very well (for me, anyway).

Anyway, we all have to do what works best for us. It’s like the brisket at 225 vs 300 or higher debate. As long as it reaches 203, how it gets there is your business 😄
 
Interesting topic (cold vs. ambient). I could never get the concept right in my head. My grandpa’s farm had lots of grazing proteins on it. The best tasting beef, pork or chicken, always came from a freshly killed animal and went straight on the grill. I never heard anyone say we should put it in a fridge and chill it so it could absorb more smoke. Another point of reference was his 5,000 square foot smoke house where he would put room temp proteins and smoke them for 2–20 days. It didn’t matter if it was ham, beef or goat, they all tasted great. Maybe I’m overthinking this but how does contracted meat (i.e., muscles are cooled and compressed) absorb anything more than room temperature? Just asking because the ultimate winner will be the pellet manufacturers if we can’t figure out the truth. Colder usually means more BTUs (fuel) expended to achieve the same temperature (final IT) as a cook starting at ambient. My only defense is listening to the guys that start their cooks at low temps in places like Maine, Minnesota and Alaska, that aren’t bragging about how much more smoke their food contains versus the folks in Arizona, New Mexico, and California. Anecdotal at best but what do I know, I’m a passenger on this ship, haha.
 
Interesting topic (cold vs. ambient). I could never get the concept right in my head. My grandpa’s farm had lots of grazing proteins on it. The best tasting beef, pork or chicken, always came from a freshly killed animal and went straight on the grill. I never heard anyone say we should put it in a fridge and chill it so it could absorb more smoke. Another point of reference was his 5,000 square foot smoke house where he would put room temp proteins and smoke them for 2–20 days. It didn’t matter if it was ham, beef or goat, they all tasted great. Maybe I’m overthinking this but how does contracted meat (i.e., muscles are cooled and compressed) absorb anything more than room temperature? Just asking because the ultimate winner will be the pellet manufacturers if we can’t figure out the truth. Colder usually means more BTUs (fuel) expended to achieve the same temperature (final IT) as a cook starting at ambient. My only defense is listening to the guys that start their cooks at low temps in places like Maine, Minnesota and Alaska, that aren’t bragging about how much more smoke their food contains versus the folks in Arizona, New Mexico, and California. Anecdotal at best but what do I know, I’m a passenger on this ship, haha.
If you’ll allow me to get a bit nerdy for a moment, it’s more about how the gases of combustion move and stick to the meat. Studies in thermophoresis show that heavier molecules (such as those in smoke) move away from a warmer surface toward a colder surface. The heavier molecules are lumbering, slow movers, and the hotter, more energetic molecules push them away.

After the smoke molecules are stuck to the cold surface of the meat, they are absorbed a short distance into the meat as the meat heats up.

Wet meat also attracts and dissolves the polar molecules and ionic compounds of the smoke, but that’s a different subject 😁.
 
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If you’ll allow me to get nerdy for a moment, it’s more about how the gases of combustion move and stick to the meat. Studies in thermophoresis show that heavier molecules such as those in smoke) move from a warmer surface toward a colder surface, because they’re slow movers, and the hotter, faster molecules can push them away.

After the smoke molecules are stuck to the cold surface of the meat, they are absorbed a short distance into the meat as the meat heats up.

Wet meat also attracts the polar molecules of the smoke 😁.
Homer Simpson Cartoon GIF
 
If you’ll allow me to get nerdy for a moment, it’s more about how the gases of combustion move and stick to the meat. Studies in thermophoresis show that heavier molecules (such as those in smoke) move from a warmer surface toward a colder surface. The heavier molecules are lumbering, slow movers, and the hotter, faster molecules can push them away.

After the smoke molecules are stuck to the cold surface of the meat, they are absorbed a short distance into the meat as the meat heats up.

Wet meat also attracts the polar molecules of the smoke 😁.
IPlay…. Good information. Would thermophoresis also be influenced by the attracting “protein’s” (in this case) ability overcome any natural barriers such as distance, density, external surface texture/tension and its ability to absorb the larger molecules? As an example, when I try to smoke 21 day dry aged beef (chilled or ambient), the smoke profile is barely apparent in my offset or vertical, stickburning cookers compared to the ambient temp meat with a similar profile, when they were cut from the same cow. Also, I wonder how efficient the absorption of smoke is influenced when the surface is cold, oiled and seasoned and exposed to smoke versus the same scenario when the ambient meat is sweating and more likely attract the molecules? An example would be when a house catches fire and the temperature is ambient, a couch absorbs quite a bit of smoke. In the same scenario with a frozen couch in the room, smoke penetration is relatively low. If we take the discussion further outside the meat discussion and use elastomers as an example, we prefer to use seals in an ambient like condition versus a cold temperature to allow for proper expansion and ”loosening” (reducing the durometer measurement to allow for more pliability thus allowing for a better compression set) so they can absorb thermal energy and fill in their own natural inclusions and cavities before exposure to gases and subsequent ignition during a launch. What are your thoughts?
 
IPlay…. Good information. Would thermophoresis also be influenced by the attracting “protein’s” (in this case) ability overcome any natural barriers such as distance, density, external surface texture/tension and its ability to absorb the larger molecules? As an example, when I try to smoke 21 day dry aged beef (chilled or ambient), the smoke profile is barely apparent in my offset or vertical, stickburning cookers compared to the ambient temp meat with a similar profile, when they were cut from the same cow. Also, I wonder how efficient the absorption of smoke is influenced when the surface is cold, oiled and seasoned and exposed to smoke versus the same scenario when the ambient meat is sweating and more likely attract the molecules? An example would be when a house catches fire and the temperature is ambient, a couch absorbs quite a bit of smoke. In the same scenario with a frozen couch in the room, smoke penetration is relatively low. If we take the discussion further outside the meat discussion and use elastomers as an example, we prefer to use seals in an ambient like condition versus a cold temperature to allow for proper expansion and ”loosening” (reducing the durometer measurement to allow for more pliability thus allowing for a better compression set) so they can absorb thermal energy and fill in their own natural inclusions and cavities before exposure to gases and subsequent ignition during a launch. What are your thoughts?
This is why science is so fun, and why I prefer the experimental sciences to theoretical science! I’d like to preface this by stating that I’m not a food scientist, and there are people here who know more than I do. But my good friend is a food scientist, so I can find a definitive answer to the aged meat question for you. Sometimes, there are variables that I haven’t thought about, because my degrees are in different scientific fields. In addition, thermodynamics is very complex, and molecular hydration shell entropy will forever haunt me! Without boring everyone with long equations that mean very little to most people, and comparing each variable for a bunch of molecular compounds, I’ll try to keep this brief, and give the Cliff Notes version.

1. There is a difference between thermodiffusion involving solids, liquids (the Soret coefficient), and gases. Probably the least understood are liquids (see the aforementioned hydration shell entropy). Gases and aerosol particles (like smoke) can have different barriers to diffusion into another substance, depending on the following:
a. The polarity and ionization potential of the molecules involved. Polar molecules and ionic compounds (salt, etc.) are only dissolved in polar liquids, such as water. Nonpolar molecules are only dissolved in nonpolar liquids, such as oil/fat. Polar aprotic solvents are a different beast, but I’m going to skip them, because you shouldn’t have much of those in your food 😆.
b. The presence or absence of a liquid will change the way that substances diffuse, as mentioned above. Diffusion is more difficult through a solid substance due to decreased particle motion and the space between molecules. This partially explains the difference between a polyester/rayon/nylon/ etc. couch, and a liquid-rich substance, such as meat.
c. The molecule itself. Totally unrelated to temperature, some molecules aren’t “structurally bonded,” so they ionize and diffuse easier. Others have extremely strong covalent bonds and behave differently. Size of the molecule also affects the ability to diffuse, especially if a cell membrane is involved (something living things have- more on that later). The molecular elements and structure itself will give each substance different characteristics of density, elasticity, and plasticity, and different molecules will behave differently when exposed to various temperatures. All of that can change how molecules diffuse through that substance. One of the hardest things for me to get used to in my advanced inorganic chemistry courses was the unpredictability of various elements and molecules, because there weren’t a lot of reliable patterns (at least not to me, but I don’t have a PhD in chemical engineering 😁).
d. There are a lot of other variables of the elements in each specific molecule, including thermal conductivity, specific heat capacity, electronegativity, etc.
e. Lastly (at least for now, off the top of my exhausted brain), meat is a formerly living thing. It’s not just a compound substance, but a variety of substances with complex organization, such as cellular membranes, intercellular and extracellular fluids, pores, and a bunch of other things. Molecules will move through each of these structures differently, AND dead tissues behave differently than living tissues.

All of this is why I’d rather just perform an experiment instead of work off of theory!

All right, now that I’ve thoroughly bored the living daylights out of everyone here, I think the biggest difference in your aged meat could be hydration. Less hydration would mean less attraction of smoke molecules, and would change the diffusion of those molecules into the meat. Secondly, if there is any fat or oil on the surface, that will result in less attraction and diffusion. Most seasonings contain ionic compounds and polar molecules that should play well with the polar smoke molecules.

Again, there are people here who know far more than I do. I’ll also try to get in touch with my friend for a more definitive answer on aged meat 😀.

Who wants ice cream?
 
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This is why science is so fun, and why I prefer the experimental sciences to theoretical science! I’d like to preface this by stating that I’m not a food scientist, and there are people here who know more than I do. But my good friend is a food scientist, so I can find a definitive answer to the aged meat question for you. Sometimes, there are variables that I haven’t thought about, because my degrees are in different scientific fields. In addition, thermodynamics is very complex, and molecular hydration shell entropy will forever haunt me! Without boring everyone with long equations that mean very little to most people, and comparing each variable for a bunch of molecular compounds, I’ll try to keep this brief, and give the Cliff Notes version.

1. There is a difference between thermodiffusion involving solids, liquids (the Soret coefficient), and gases. Probably the least understood are liquids (see the aforementioned hydration shell entropy). Gases and aerosol particles (like smoke) can have different barriers to diffusion into another substance, depending on the following:
a. The polarity and ionization potential of the molecules involved. Polar molecules and ionic compounds (salt, etc.) are only dissolved in polar liquids, such as water. Nonpolar molecules are only dissolved in nonpolar liquids, such as oil/fat. Polar aprotic solvents are a different beast, but I’m going to skip them, because you shouldn’t have much of those in your food 😆.
b. The presence or absence of a liquid will change the way that substances diffuse, as mentioned above. Diffusion is more difficult through a solid substance due to decreased particle motion and the space between molecules. This partially explains the difference between a polyester/rayon/nylon/ etc. couch, and a liquid-rich substance, such as meat.
c. The molecule itself. Totally unrelated to temperature, some molecules aren’t “structurally bonded,” so they ionize and diffuse easier. Others have extremely strong covalent bonds and behave differently. Size of the molecule also affects the ability to diffuse, especially if a cell membrane is involved (something living things have- more on that later). The molecular elements and structure itself will give each substance different characteristics of density, elasticity, and plasticity, and different molecules will behave differently when exposed to various temperatures. All of that can change how molecules diffuse through that substance. One of the hardest things for me to get used to in my advanced inorganic chemistry courses was the unpredictability of various elements and molecules, because there weren’t a lot of reliable patterns (at least not to me, but I don’t have a PhD in chemical engineering 😁).
d. There are a lot of other variables of the elements in each specific molecule, including thermal conductivity, specific heat capacity, electronegativity, etc.
e. Lastly (at least for now, off the top of my exhausted brain), meat is a formerly living thing. It’s not just a compound substance, but a variety of substances with complex organization, such as cellular membranes, intercellular and extracellular fluids, pores, and a bunch of other things. Molecules will move through each of these structures differently, AND dead tissues behave differently than living tissues.

All of this is why I’d rather just perform an experiment instead of work off of theory!

All right, now that I’ve thoroughly bored the living daylights out of everyone here, I think the biggest difference in your aged meat could be hydration. Less hydration would mean less attraction of smoke molecules, and would change the diffusion of those molecules into the meat. Secondly, if there is any fat or oil on the surface, that will result in less attraction and diffusion. Most seasonings contain ionic compounds and polar molecules that should play well with the polar smoke molecules.

Again, there are people here who know far more than I do. I’ll also try to get in touch with my friend for a more definitive answer on aged meat 😀.

Who wants ice cream?
EXCELLENT, EXCELLENT, EXCELLENT!!! I applaud your knowledge and your response. Especially the comment about “…[E]xperiment instead of work off theory.” I was equally excited when I found out an F/A-18 Hornet can suspend itself in the air if you set the angle of attack and engines properly to overcome all present forces. You can actually bring the air speed indicator to zero. This being said, I look forward to following your responses to the threads and your expertise as it can only result in a transfer of knowledge to my sponge like brain in a positive manner. I will also try to simiulate (in the yard not the lab) future cooks to see if it can be validated that cool is better than ambient. So far my experience shows the opposite of what the science indicates. If you or any of the forum team members have any suggestions, I have plenty of pellets to burn with my futile attempts. I also apologize to the forum for hijacking this thread, and in advance for reserving the right to re-engage periodically as this is what I hope this forum is about. Professionalism, respect, exchange of ideas and fun. I salute you IPlay.
 
I'm getting back on the short bus and leaving.
 
I'm getting back on the short bus and leaving.
Get back here on the nerd bus where you belong! I’m pretty sure you can get into trouble for hopping off the bus without permission 😉.
 
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EXCELLENT, EXCELLENT, EXCELLENT!!! I applaud your knowledge and your response. Especially the comment about “…[E]xperiment instead of work off theory.” I was equally excited when I found out an F/A-18 Hornet can suspend itself in the air if you set the angle of attack and engines properly to overcome all present forces. You can actually bring the air speed indicator to zero. This being said, I look forward to following your responses to the threads and your expertise as it can only result in a transfer of knowledge to my sponge like brain in a positive manner. I will also try to simiulate (in the yard not the lab) future cooks to see if it can be validated that cool is better than ambient. So far my experience shows the opposite of what the science indicates. If you or any of the forum team members have any suggestions, I have plenty of pellets to burn with my futile attempts. I also apologize to the forum for hijacking this thread, and in advance for reserving the right to re-engage periodically as this is what I hope this forum is about. Professionalism, respect, exchange of ideas and fun. I salute you IPlay.
Thank you, @SmokeZilla ! I truly appreciate the respectful exchanges of information here. I’m always looking to learn more, and that’s some pretty awesome knowledge you just dropped there! I think you’ll find that there are a lot of very intelligent, insanely knowledgeable members here, many of whom are a lot smarter than I am. That’s just one of the reasons I am slightly addicted to this place 😁.

Also, I think you’ll enjoy a lot of Meathead’s resources, if you haven’t already, such as amazingribs.com and his book. The science is solid, and he has some experiments that explain things in a much more effective way than I can.

Happy cooking, and thank you to all of you for your patience while I went into full nerd mode!
 
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