Bacon curing - validating the 10% uptake assumption

  • Some of the links on this forum allow SMF, at no cost to you, to earn a small commission when you click through and make a purchase. Let me know if you have any questions about this.
SMF is reader-supported. When you buy through links on our site, we may earn an affiliate commission.
I am interested to see if the Loins will be closer to 10% after 14 days...JJ
 
Well, I finally ran into it, while looking up a different question..... I knew I saw it somewhere....

http://www.meatsandsausages.com/sausage-making/curing/methods

Overhauling
•Overhauling means periodic re-arrangement of meat pieces that are inside of a curing container. It is done for the following reasons:
•There will be less curing in areas where meats touch each other. Under cured meat areas may have different shade of pink color.
•The curing solution will have sections of different density-salt will sink to the bottom, nitrate will swim up to the top
•When meats are placed on top of each other the top layers supply pressure to the bottom section and the meat juices will leak out into the brine. That is why meats should not be stacked higher than 3 feet.

The strength of the solution will change in time, salt might settle on the bottom, nitrites might be on top, some meat juices will enter the brine, meat pieces may touch each other etc. To allow all meats to cure evenly, the solution should be remixed and agitated. A rule of thumb is to overhaul the meat every seventh day for three weeks. A smaller piece that will be cured for 10 days only, should be overhauled after 5 days. The easiest way is to use two separate containers and switch the meats from one container to the other. The pieces that were on top are now on the bottom and vice verse. Then the brine can be stirred and poured over meat pieces in a new container. If only one container is used the meat should be removed, the brine stirred, and the meat reinserted in a different order.

+++++++++++++++++


That's BS......   Someone was guessing....

The size of the molecules.... the shape of the molecules....   their polarity.... and their density....    etc.   all determine the "speed" at which equilibrium takes place...   the same can be seen in an expensive drink at the bar....   different separations in a drink from different booze...  that's why fresh water floats on top of salt water....  cold water "sinks" and warm water "floats"... 

Some molecules move fast..... some move slow......    Like the statement in overhauling bellies in a brine solution....   the salt has tendency to "sink" toward the bottom of the vat, while the sodium nitrite "tends" to float toward the top... and thus, overhauling should be done ...

The brine has to work it's way through a network of muscle tissue...  The tissue acts as a filter....   molecular sieve so to speak...

++++++++++++++++++++++++

" [COLOR=181818[B]]the salt has tendency to "sink" toward the bottom of the vat, while the sodium nitrite "tends" to float toward the top... and thus, overhauling should be done ... "[/COLOR]

Dave, can you provide some more detail and a link where I can get more info on this?
[/B] College Chemistry was a LONG time ago but the whole bases of Diffusion is that Salt will move from an area of high concentration to one that is lower or non-existent to reach equilibrium. This rate of diffusion ( Flux ) in water will vary by the concentration, high concentration can result in ion collisions slowing the process slightly, low concentration ions move in virtually a straight line to the area of lowest concentration thus diffuse at a faster rate. Lastly heating the solution increases the speed of diffusion. Once eguilibrium is reached we have by definition no net flux or no steady movement between concentrations. However since we mix brines these processes are irrelevant. The ions of dissolved Sodium Nitrite will act in a similar manner. While flux does not have to be a steady zero once equilibrium is reached, the molecules can move within the water if for any reason the concentration changes, moving into the meat , however the Net Flux must be zero, any changes will equalize to maintain the same overall concentration, equilibrium is maintained. Is this incorrect? Thanks...JJ


http://michaeldmann.net/mann1.html
 
Overhauling
•Overhauling means periodic re-arrangement of meat pieces that are inside of a curing container. It is done for the following reasons:
•There will be less curing in areas where meats touch each other. Under cured meat areas may have different shade of pink color.
•The curing solution will have sections of different density-salt will sink to the bottom, nitrate will swim up to the top
•When meats are placed on top of each other the top layers supply pressure to the bottom section and the meat juices will leak out into the brine. That is why meats should not be stacked higher than 3 feet.

The strength of the solution will change in time, salt might settle on the bottom, nitrites might be on top, some meat juices will enter the brine, meat pieces may touch each other etc. To allow all meats to cure evenly, the solution should be remixed and agitated. A rule of thumb is to overhaul the meat every seventh day for three weeks. A smaller piece that will be cured for 10 days only, should be overhauled after 5 days. The easiest way is to use two separate containers and switch the meats from one container to the other. The pieces that were on top are now on the bottom and vice verse. Then the brine can be stirred and poured over meat pieces in a new container. If only one container is used the meat should be removed, the brine stirred, and the meat reinserted in a different order.
 

In my dad's store, that would be impossible to accomplish.  We stacked bellies (albeitly alternating directions, but still one on top of another) in a 55 gal. poly drums 5' tall, filled with brine, then put in the cooler to soak, weighing down with 5 gal. water bags, for 21-30 days in a curing brine cooler with 60 other barrels, all on dollies to easily move as necessary, then pulled into roll trucks and taken into the smokehouse room, placing bacon hooks in them and smoking 8-10 hours.  Usually filled one smokehouse with bellies and the other with either hams or custom.
 
Thanks Dave. I had no doubt you read that info. I was just curious as to whether it was written by a Scientist with a PhD in Chemistry or a Chemical Engineer or a Curing Article. While I can understand Overhauling, for most of the reasons stated, that article is the only time I have seen that dissolved salts can settle or float in water. Salts are a molecule made of the atoms of a Metal and a Non-metal held together by an Ionic Bond, they share Electrons, a pretty weak force.  Chemically what that article says can't happen since both Sodium Chloride and Sodium Nitrite, Polar Solutes, dissolve into their separate positively charged Sodium Ions ( Na+) and negatively charges Chloride Ion (Cl-) and Nitrite Ion (NO2-) in Water, a Polar Solvent. In a Brine the solution is nowhere near Saturation because there is a lot more water than either the amount of NaCl or NaNO2.  In our Brine solution there is a Solute-Solvent Interaction. In this case all the Solute (NaCl and NaNO2) is torn apart into their respective Ions by the strong polarity of the water. These Ions become immediately surrounded by water molecules in the form of a Primary Hydration Shell. The negatively charged Oxygen portion of the water molecules surround the Na+ ions (Cations) and positively charged Hydrogen portion of water surrounds the Cl- ions (Anions). A similar interaction happens with NaNO2. This is not to say that the ions are " Locked into place ", they can move about but the attraction of all that water is much stronger than the attraction of the Cations to the Anions of the original chemical molecule. Now add the meat. A portion of all these ions will Diffuse into the meat, this leaves even less ions saturating the Water. With so much water holding on to so FEW ions, how can they settle or " swim up to the top " ? Sorry, I just don't see how this can happen...
th_dunno-1%5B1%5D.gif
...JJ

http://www.newton.dep.anl.gov/askasci/chem00/chem00297.htm

http://www.kentchemistry.com/links/bonding/LikeDissolveslike.htm
 
Last edited:
With each brine the weight increases were similar however they varied significantly between meat cuts. Both loins showed an increase in weight of ~7% whereas the bellys increased between 11.5% and 13.75%

Interesting results Wade, I would have guessed the loin would have picked up more weight then the belly. Any thoughts on the difference?
 
I think the layers of fat have an effect on water adsorption... I think each meat muscle group, will adsorb brine at different rates...
 
Hi Dave - Thanks for continuing to search - I know the frustration when you know you have seen something but just can't put your finger on it again.

Having looked at the article though I think maybe it was a bit of a general off-the-cuff statement rather than a scientific fact. From my days back when I used to work in the medical research labs, if I recall correctly, once a salt (or salts) were dissolved in liquid water and thoroughly mixed, they would then remain in homogeneous solution if under the same conditions. You maybe could get concentration gradients if there was undissolved salt crystals at the bottom of the container however these brines are really quite weak salt solutions (in the grand scheme of things) and so  the salt should all remain in solution.

One thing that may possibly (?) effect the salt concentration could be that in a fairly well loaded brining container (where there was more fluid space at the bottom of the container than at the top round the meat),  IF  the meat at the top was actively absorbing the cure then may make the solution around it slightly weaker. If so then without periodically mixing it could take time for the more concentrated salts at the bottom to diffuse to the top. This is pure speculation on my part though and in practice I would expect any gradient in the container to be minimal.

I think for the reasons that JJ has mentioned above, the comment regarding the Nitrate/Nitrite floating to the top and the salt sinking to the bottom is incorrect. I now run the IT in a school and so I passed this by our Head of Chemistry (who has a chemical engineering PhD) and he confirmed that this was not a property of solutions that he recognised. Having said that though, he says he does recommend students to shake solutions that have been standing for a while before using them - but that is really to ensure that none of the dissolved salts have crystallised out.
 
Interesting results Wade, I would have guessed the loin would have picked up more weight then the belly. Any thoughts on the difference?
I think that maybe it is an effect caused by the surface area of the meat that is exposed to the brine. The belly joint is thin and flat and has many ridges and troughs and so has a significantly greater surface area to absorb the brine compared to its volume than the loin. My gut feeling though (no pun intended) is that given time both will probably end up being able to absorb similar amounts of brine for any given amount of muscle - but as the loin has proportionally more muscle and less fat than the belly it may eventually even be able to absorb more brine weight-for-weight.

It will be interesting to see what actually happens after the 14 days. If the belly eventually reaches saturation then maybe the loin will get a chance to catch up.
 
I find the statement below to be of some interest.... I don't discount the possibility of the brine/cure changing concentration, and I am convinced, overhauling to maintain a homogenous solution should be observed.... Whether the summation is correct or not, is not the point... Common sense plays some role in achieving the most uniform results possible...
To each his own...


The strength of the solution will change in time, salt might settle on the bottom, nitrites might be on top, some meat juices will enter the brine, meat pieces may touch each other etc. To allow all meats to cure evenly, the solution should be remixed and agitated
 
Regardless of the chemistry I gentle agitate the meat in the brines daily to ensure that they remain well mixed. I also turn my dry cure packs daily.
 
After 5 days if resting in the fridge the 7 day cure batches were ready for slicing.

Before slicing each batch was again weighed to see if there was any weight loss as the meat drained during the rest period. There was a very slight weight loss in all if the samples however this was only an average of 0.4% for the Loin and 1.2% for the belly.

Each bactch was sliced individually with the test samples taken straight from the slicer. Each sample for testing were slices taken from the centre of the joint. The slicer was stripped and washed down between batches being sliced to avoid any cross contamination.


The picture above shows the end of each joint in front and the slices behind. The vac-packed test samples standing at the back just before freezing

The two joints on the left are Brine #1 (Loin and Belly) and on the the right are Brine #2 (Loin and Belly).

Notice with both brines how much darker red the belly is than the loin.

Next update on Monday when the 14 day batches come out of the brine.
 
Last edited:
Sorry I lied about the next update. It is in fact today.

The Dry Cure joints came out of the vac pack today after 10 days.


After rinsing and patting dry they were weighed. The Loin was exactly the same weight as it was went into the the cure. The Belly had actually increased in weight by 1.4% (13g).

The dry cure loin joint looked to be a much deeper red than either of the brined loin joints. This may only be surface colour though. We will see inside once it has rested for 5 days.
 
Last edited:
I think vac-packing may have squeezed the meat so uptake was not possible...

In a rigid vac-tub, applying vacuum would open the pores... subsequent vac, no vac, vac.... would pump the meat and force the brine in....

Todd Johnson did a similar study using beef jerky in his "Vac Tumblers" he sells...
 
This being the Dry cure I would not necessarily expect to see any increase in the weight of the meat. The maximum additional weight it could possibly gain would be the total weight of the dry cure itself. These was some brine formed around both joints so maybe the loss of water was pretty much balanced by the uptake of salts. We will be able to tell when we cut it and see how much was taken up once we get the lab tests back.
 
My error.... I'm really stupid at times... I assumed...(you know the definition). because you were "weighing", it was in a brine solution.... stupid, stupid and really stupid of me.....

Thanks Wade.....
 
SmokingMeatForums.com is reader supported and as an Amazon Associate, we may earn commissions from qualifying purchases.

Hot Threads

Clicky