Fishing with Rod Discussion Forum
Fishing in British Columbia => General Discussion => Topic started by: coho killer on January 27, 2009, 12:05:35 AM
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It seems whenever i put roe in my frezer it drys right out. Is there an approximate tempture for frezing it?
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I place a piece of paper towel on top of my roe prior to putting the lid on the container.
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try storing it in glass canning jars. I have kept roe 4-5 yeares with no problem. Burn a small peice of paper when putting the lid on it. You can get a dozen jars for about $10.00 at Save on or CTC.
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I vacuum seal my roe to avoid it getting freezer burned.
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try storing it in glass canning jars. I have kept roe 4-5 yeares with no problem. Burn a small peice of paper when putting the lid on it. You can get a dozen jars for about $10.00 at Save on or CTC.
Nice idea, you still get the canning/vac seal, without having to heat it.
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thx guys
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try storing it in glass canning jars. I have kept roe 4-5 yeares with no problem. Burn a small peice of paper when putting the lid on it. You can get a dozen jars for about $10.00 at Save on or CTC.
Nice idea, you still get the canning/vac seal, without having to heat it.
Actually you are not creating a vacuum seal when you burn paper or a match in your roe before you put the lid on. All you are doing is removing the oxygen through combustion and turning it into CO2 and Water.
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technically it is a vacuum
because the air shrinks as it cools
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try storing it in glass canning jars. I have kept roe 4-5 yeares with no problem. Burn a small peice of paper when putting the lid on it. You can get a dozen jars for about $10.00 at Save on or CTC.
Nice idea, you still get the canning/vac seal, without having to heat it.
Actually you are not creating a vacuum seal when you burn paper or a match in your roe before you put the lid on. All you are doing is removing the oxygen through combustion and turning it into CO2 and Water.
hahahaha good point einstine
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technically it is a vacuum
because the air shrinks as it cools
Correct sir. Since it heats the air left at the top of the jar you get your vacuum. If you magically managed to light the match while the jar was sealed, and the match wasn't a match, but say methane, and it burned perfectly, it would be a simple conversion to co2 and water, and he would have been right. ;D
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Urg. I just spent the last half our typing a response to your post only to hit the back button and erase everything. My post included calculations using the ideal gas law to back my hypothesis. So long for that. :'(
Anyway, Camtheman you cannot over simplify it to "the air shrinks as it cools" because when you seal the lid on it is basically at the same temperature as where it will be when it cools. Therefore causing little to no change in volume or pressure as both are state properties.
And Work2fish, ALL organic materials including matches, paper, and methane produce CO2 and Water (as steam) when they burn. Some impure organics will produce other oxides when they burn as well. By definition an organic material is composed of Carbon and Hydrogen atoms and when ignited produce CO2 and Water.
I'm in Materials Engineering, I should know this stuff.
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Urg. I just spent the last half our typing a response to your post only to hit the back button and erase everything. My post included calculations using the ideal gas law to back my hypothesis. So long for that. :'(
Anyway, Camtheman you cannot over simplify it to "the air shrinks as it cools" because when you seal the lid on it is basically at the same temperature as where it will be when it cools. Therefore causing little to no change in volume or pressure as both are state properties.
And Work2fish, ALL organic materials including matches, paper, and methane produce CO2 and Water (as steam) when they burn. Some impure organics will produce other oxides when they burn as well. By definition an organic material is composed of Carbon and Hydrogen atoms and when ignited produce CO2 and Water.
I'm in Materials Engineering, I should know this stuff.
You should know this stuff, but apparently you don't ;D The small amount of air in the jar gets heated by the flame before you can get the lid on. When the jar goes back to room temperature that air cools causing the vacuum. It's not much of a vacuum, but it's enough to draw the lid of the jar down. The only change that matters here in creating the vacuum is the temperature change of the air in the jar. What happens after the lid is put on doesn't matter since it's now a closed system. So yes, you kinda can simplify it with "the air shrinks as it cools", or a little bit more complicated with your ideal gas law, PV=nRT, since V,n, and R remain constant, and T changes, and P is unknown it must also change in response to the temperature decrease, by decreasing. Now so long as the air in the jar is not heated to the temperature it was when it was sealed, there will be a small vacuum.
The burning that occurs once you seal the jar doesn't is really irrelevant ,as well as the lid heating up. It's only the heated air that matters.
While it's true co2 and water are produced, what I was hinting at is that you would never get perfect combustion from paper. It wouldn't be the "ONLY" thing you'd get. You wouldn't get perfect combustion with methane either, but again I was talking about a magic jar where anything is possible. CO2 and water are the "only" byproducts in "perfect" combustion which rarely occurs, and wouldn't be occurring in this situation. CO, NO2, and "soot" are produced along with other impurities in the paper, and the air. But thanks for the attempt at a grade 8 level science lesson. :P
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Ok so you know your stuff too. So I'll get right into my theory.
Light a candle and place your fingers about an inch away from the flame and see how hot it is. It's probably only around 80 degrees C. And by no means of the imagination would it be that same temperature at the edge of the jar (assuming mouth of jar is ~4"). In the ideal gas law T is measured in Kelvin. This means that the Delta T (hot to cold) divided by T cold (~298 K) is relatively close to 1 meaning that the pressure ratio from atmospheric to in the jar is also close to one. This whole calculation assumes that a flame from a match or candle could heat the whole space radial to it to the same temperature you feel an inch away. This is a very conservative assumption. With a rough calculation in my head i found it would be about the pressure of being 2-3ft under water.
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Yes I fully concur (said with a wide smile on my face) but is the roe any better after say 6 months in the freezer?
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Ok so you know your stuff too. So I'll get right into my theory.
Light a candle and place your fingers about an inch away from the flame and see how hot it is. It's probably only around 80 degrees C. And by no means of the imagination would it be that same temperature at the edge of the jar (assuming mouth of jar is ~4"). In the ideal gas law T is measured in Kelvin. This means that the Delta T (hot to cold) divided by T cold (~298 K) is relatively close to 1 meaning that the pressure ratio from atmospheric to in the jar is also close to one. This whole calculation assumes that a flame from a match or candle could heat the whole space radial to it to the same temperature you feel an inch away. This is a very conservative assumption. With a rough calculation in my head i found it would be about the pressure of being 2-3ft under water.
Thanks for this, I needed a good giggle this morning. Thanks for proving my point with your theory. You realise you've done that right?
It's kinda funny, but there's this kiddie experiment, (well grade 9 in saskatchwan according to google) where many kids will jump to the same conclusion you did that it's the conversion of CO2 and water that causes the lid to suck down.
Also, I don't really feel like burning my fingers to see how hot something is, I use this nifty thing called a thermometer. Or a quick check will tell you a candle burns at about 1070k to 1670k depending on what part of the flame your talking about (which is incidently hotter than paper). I would also suggest you don't taste any chemicals to see what they are either, as that can be bad really for you. How about you brush up on your scienctific method with the same lesson they teach to those grade 9 students.
http://www.saskschools.ca/curr_content/science9/chemistry/lesson2.html
It's really cool and even has pictures so it might be easy for you to follow.
Here's another one with the answer included, but no peeking now! http://www.stevespanglerscience.com/experiment/00000022
And be careful! As the experiment guide saya": This experiment requires the help of an adult partner. Don't just pick any adult... try to find a smart one!
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How did a simple question on roe turned into a chemistry lesson ? ;D
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How did a simple question on roe turned into a chemistry lesson ? ;D
Probably due to a lack of wanting to do any real work. :D and that there are not any shopes like this around: http://www.youtube.com/watch?v=teMlv3ripSM
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work2fish, I must not be conveying my message clearly. First of all I am not claiming the chemical reaction is what causes the pressure change nor did I ever claim it did. I was pointing out it was the removal of oxygen (through combustion) that helps prevent freezer burn, since freezer burn is the oxidization of fats and proteins in the roe.
Secondly my point is that by lighting a candle you do NOT instantaneously make the entire area around it 1000 Degrees. It's a heat transport problem. The AVERAGE temperature once the lid is sealed will not be a thousand degrees. It will be far from that. You must not of read the part were i said "an inch away from the flame." You can't honestly believe that in the time it takes for a match to burn an inch that it would be enough time for the entire area at the mouth of the lid to reach an equilibrium temperature of a 1000 degrees?
The example you provided does not relate. Neither an egg nor a water balloon will form a tight seal around the lid of the jar (it's in the answer. I peaked) and therefor it is not a closed system. Our jar lid does form a tight seal and can be considered a closed system.
And if you really need to belittle me to try and prove your point you must slowly be realizing that you are wrong and that the only way out is either to admit you are wrong or try and make me look stupid. Nice Try.
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work2fish, I must not be conveying my message clearly. First of all I am not claiming the chemical reaction is what causes the pressure change nor did I ever claim it did. I was pointing out it was the removal of oxygen (through combustion) that helps prevent freezer burn, since freezer burn is the oxidization of fats and proteins in the roe.
You never said anything about freezer burn. What you did say was "Actually you are not creating a vacuum seal when you burn paper or a match in your roe before you put the lid on. All you are doing is removing the oxygen through combustion and turning it into CO2 and Water. "
Secondly my point is that by lighting a candle you do NOT instantaneously make the entire area around it 1000 Degrees. It's a heat transport problem. The AVERAGE temperature once the lid is sealed will not be a thousand degrees. It will be far from that. You must not of read the part were i said "an inch away from the flame." You can't honestly believe that in the time it takes for a match to burn an inch that it would be enough time for the entire area at the mouth of the lid to reach an equilibrium temperature of a 1000 degrees?
And I didn't say it "instantanously" heated the air to 1000C, nor does it need to be 1000c to create a vacuum.
The example you provided does not relate. Neither an egg nor a water balloon will form a tight seal around the lid of the jar (it's in the answer. I peaked) and therefor it is not a closed system. Our jar lid does form a tight seal and can be considered a closed system.
Actualy it does, in that it relates to creating a vacuum in the bottle. By heating the air in the bottle, then creating a seal with the egg, as the air cools it creates a small vacuum presure.
And if you really need to belittle me to try and prove your point you must slowly be realizing that you are wrong and that the only way out is either to admit you are wrong or try and make me look stupid. Nice Try.
Naw, not trying to belittle you, or make you look stupid, you've doing a fine job of that yourself. ;D
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I don't want to have to explain every line I type to you. So I'm leaving it as is. You believe what you want and I'll believe what I think is right.
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try storing it in glass canning jars. I have kept roe 4-5 yeares with no problem. Burn a small peice of paper when putting the lid on it. You can get a dozen jars for about $10.00 at Save on or CTC.
I use this method as well and it's an excellent way to freeze roe. I buy used jars from MCC and other Christian second hand outlets for $1 to $2 a dozen. Even though the jars are used they look new and since I am using them for freezing roe and keeping gardening seeds I don't need to use brand new jars. You can get them in different sizes as well. There are many stores like this in the Fraser Valley.
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im lost but thanks for all the advice