We encounter more problems with beef cow hides than any other hair on skins. After 18 years I finally have concluded that the critical time for ensuring a good tan on a beef hide begins with the butcher.
Most adult cowhides are thick and therefore require some time to cool out. This is where the problems begin. Butchers are more concerned with the carcass than the hide. Cuts and skinning marks are caused by the skinners simply because they want to protect the meat. When meat processors have a hoist system to remove the hide, very little damage is done to the skin by way of knives. However, when a skin is removed from the carcass, it is usually laid in a pile off to the side until the skinners have time to drag it outside or to the hide pit. In a matter of less than 1 hour, you can have heat damage to the skin which results in hair or epidermis slip during the tanning process. To make matters worse, even if the customer has informed the processor that they want the hide tanned, it will eventually be rolled or folded up, hair side out, placed in a cardboard box and slid in the freezer.
Here is what just happened………..the warm hide around 90 degrees is thrown on the floor in a heap; the heat from the skin never has a chance to decrease much. Worse yet, if it is summer, the outside temperature may be even higher and there is no cooling of the skin. The neck and back are the thickest and thus contain heat longer and are more prone to heat and bacteria damage. The tail is seldom split open, leaving the bone intact. If the processor has a basement or salt pit, the hide may be dragged to it until someone has time to salt it, even then it is “salt packed”, which is fine for skins being processed into leather but bad for hair on tanning. Or, the hide is finally folded up, usually hair out, because they don’t want the bloody thing to get all over the floor or person dragging it around. This of course seals the heat and skin fluids within the hide and does not allow for cooling. Then, this hot bloody, manure covered skin is slid in the cooler or freezer and allowed to freeze. Of course the skin is covered with hair, which God put there to keep the animal from freezing. This hair, no matter how thin, will do its job and delay freezing. Eventually the skin will freeze, but the inside of the roll of folded hide will take about 4-5 hours to freeze solid, Meanwhile, bacteria is having a hay day! It breaks down the membrane surrounding each hair follicle and the thin layer of epidermis, cause eventual hair slippage. Or worse, salt it first and then freeze it.
Now you have a really bloody and runny hide that may never freeze and bacteria can live quite well in a saline solution.
You reply, “I don’t have the time to flesh and salt this skin, so what do I do?????”
OK, first of all, be there when the animal is skinned, pull the hide over to an area either inside or outside and open it up completely with the hair side down, If outside, try to find a shady spot. Let it cool for at least 30 minutes or until it is cool to the touch. If you cannot flesh the excess meat and fat from the skin, please do not salt it, this only shrinks the meat and fat and makes it quite difficult to remove and you end up cutting the hide trying to flesh it. Also, the salt dries out the meat and fat and never reaches the skin itself.
Bacteria become dormant or die at 15% moisture or less.
Once the hide has cooled and you have decide to freeze it until you can figure out what to do with the skin, fold the skin in half, hair to hair side, then fold again, and again until it can fit in a cardboard box, if possible, try not to place in a plastic garbage bag, these just hold in the heat longer. Freeze as soon as possible and place on a wooden pallet also, This allow the cold air to reach the bottom of the hide. Now understand, this is not the best way to handle a fresh hide, but it is better then doing nothing for a couple of hours.
When the skin is ready to flesh or salt, you must soak the hide in a salt solution, using at least 50lbs of fine or medium grained salt in a 50 gal plastic barrel. Use warm but not hot water to mix the salt in, (it dissolves better), Once the salt is mixed, you can add some Pinesole or other disinfectant, about 1 or 2 cups will work. Place the frozen skin in the solution, it will float, so if you can force it under the surface, all the better. Now, don’t go off for a couple days and forget about it. You will need to pull the skin apart as it thaws out, allowing it to thaw more evenly.
Why do this instead of just letting it unthaw on the shop floor, Well, because it thaws the same way it froze, the outside will thaw first and the inside last. Once thawed, the bacteria become active and begin to break down the skin. The salt helps to cure the skin and the disinfectant kills bacteria.
Once the skin is completely thawed, dump the bloody water and place the skin on a rack of some type to drain, or just hoist it up by the tail above the ground and allow the fluids to drain. Once drained, proceed to remove any meat or fat over 1/4 inch in thickness from the skin, The better job you do, the better the tanning results. Lay the fleshed skin, hair side down on a pallet or two and salt with at least 100lbs of stock salt, fine or medium. NO ROCK SALT! If you can incline the skin, all the better. The fluids will run off quicker and the skin will dry faster. I recommend laying a 2×6 on edge and laying wooded pallets along the edge of the 2×6, you may need to nail or screw them to keep from falling over. Cement blocks work well for this also as a high center point. If in a humid climate, run a fan over the skin to increase evaporation of fluids. It will take about 7 to 10 days for a large cow skin to dry. Once the salt is dry to the touch and fluids have ceased to drain, flip the skin over and let the hair side dry. DO NOT LET IT DRY STIFF.
The skin should still be pliable and able to fold. It should be laying there with the hair up, right? OK, now fold it in half long-ways, hair to hair, neck to tail, fold the belly area over again to decrease the width, or fit the container you plan on putting it in. Roll or fold from the neck to the tail and place in cardboard box, Please do not put in plastic bag first.
The 100 lbs. of salt you placed on the skin should have dumped off when you flipped the skin over to allow the hair side to dry. Don’t ship salt with the hide, it is expensive and I don’t need it. There will be some, of course, that remains on the skin, leave it!
Now the hide will continue to dry while in the box, leave the lid open to allow for evaporation. The longer you wait to ship, the lighter the skin as moisture evaporates. You can wait for a couple months if you want. Always ship before Wednesday, thus the skin does not sit in a heated UPS warehouse over the weekend. There should not be any fluids leaking from the box, because you have dried the skin out, right!!!
If you choose to ship the frozen skin to any other tannery or us (most do not accept frozen skins) understand that you are taking a risk in spoilage from thawing in route. If you just do not want to hassle with fleshing and salting, follow the instructions at the processor about cooling the skin and get immediately to a tannery or taxidermist. It helps to notify them in advance of your intentions and the day you plan on butchering the animal. Please do not take the bloody skin to them unannounced at 5:00 p.m. and expect a happy camper.
Best to try and have the animal skinned in the cooler mornings.
Best of luck and if you are still confused, call me!