Plastic gets a Bad Wrap
"Paper or Plastic?" In the old days you typically would hear that at a grocery store check out. But no longer in Colorado. What used to be a pretty square state has been making the news quite a bit lately. Some things are good, and some bad. If you watch the news you probably only see the bad unless you are Liberal in your persuasion. I don't watch the news, in fact I don't even have a T.V. in my house. But we'll take that rabbit trail some other time.
You may have heard that recently Colorado and a few other states have done away with plastic grocery bags at all stores. Yep, no more Wal-Mart bags. And I was just beginning to have quite a collection to try and use for snow goose decoys. Oh well. I could go either way with the grocery bag issue, I get it.
On a recent trip to Cody WY, I came in from the south and that Hwy goes past the dump. Although you cant actually see the dump itself, you could definitely see it was evident. Literally thousands of white bags covered the landscape due to the wind blowing over the hill that the dump was tucked behind. They were mostly Wal-Mart bags as the town had just gotten a new store.
You are probably asking yourself right now, so what does this have to do with a game bag? Well, nothing really, only to introduce a topic from the stand point of a common misconception with using plastic wrap in leu of common game bags.
I will warn you now that this is a lengthy read. So here are 4 key takeaways if you don't get through it all.
1. There is a difference between evaporation and convection of heat but the end result is the same.
2. There is no more heat being produced once an animal is dead.
3. The hide and the ground have the most insulation value.
4. Moisture is actually not the enemy. The blood however, is.
5. Using plastic wrap is like putting the hide right back on but without it's insulating value
Ok that was 5 and if I still have your attention then keep reading, otherwise you will have to come back and read this after it crosses your mind while field processing your next game animal.
The Bad Wrap
When it comes to wild game processing in the field I now speak on the ire of all game meat connoisseurs. I am about to dive into the topic of wrapping game meat in plastic wrap right after parting the animal out in the field. The term wrap includes names like Saran wrap, Cling wrap, Glad wrap or whatever, you name it. All these names are referring to the stuff you would buy today on the shelf at the grocery store in the food storage isle.
I know a lot of folks using Saran wrap or "meat wrap". You might be one of them and have experienced it's benefits first hand. But this might be a totally new concept for many of you as well, and upon first thought you may be very skeptical about it.
I personally have been using cling wrap for over 20 years. Actually, we started by using the big commercial shrink wrap rolls until it was discovered that it wasn't food grade plastic. Then my brother went to (here we go again) Wal-Mart and got a 250' roll of Cling Wrap to quarter an elk. The rest is history. In most circumstances I may never use a conventional game bag again. Yes, even in early season. However, initially using a game bag and then removing the bag and using meat wrap after a cool down period is a great strategy.
Pack out and meat storage time afield should be determined by the daytime temps. When using meat wrap with say 65 degree highs and 40 lows then I must get the meat out to an electric or iced cooler within 3 days. And I will always keep the meat shaded.
The key terms when talking about cooling game meat are Conduction, Convection, Evaporation, and Insulation. All of these play an important role.
Conventional game bags have been around a long time. They do their job in all four of the above key terms and are fairly simple to use and quick no doubt. I'm not here to discount their function. There has been an evolution in the game bag that brought it out of the old cheese cloth days, into the heavy tent canvas days, then the linen pillow case days, and now the glorified pillow case days, e.g. major hunting gear brands putting a logo on some synthetic material and adding a string closure at one end. These "pillow case" game bags by the way are made of a plastic cloth, Nylon mostly, and are food safe.
Any brand name game bag should be made of food safe material. But if you are the parsimonious type, beware of using any bag that may contain a fabric or material that is not food safe. It can quickly leach harmful stuff into your game meat simply by touching it. Garbage bags are an example of this type of a cheap and easy game bag. But they are not recommend here.
A more recent development is a conventional cloth game bag infused with anti microbial agents to limit bacterial growth. There can be some benefit to this kind of bag, but if you are worried about bacteria the only thing that will prevent it from growing is a temperature below 45 degrees. Or not allowing the bacteria to get on the meat or enter the game bag in the first place.
Some folks quarter a game animal leaving the hide on and cutting the hide so they can fold it back over the inner portions of the quarter that were separated from the main carcass. This is a good way to do it but only in temps below 50 degrees and if your pack out plan is short and sweet.
I have even seen an article published in a major outdoor hunting journal that suggested this method but then also suggested literally dragging your quarters out on the ground individually, pulling them with a rope. I would not recommend this at all unless it is on snow the majority of the way and you have enough hide to completely cover all around each quarter and stitching it together with string or paracord. In doing it this way you will keep a majority of the surface of the meat un-exposed to any contaminates. This method may sound very nostalgic, but the hide is very insulated and will inhibit cooling of the meat, and then you will be dealing with cleaning a lot of hair and dirt off the exposed areas of the meat.
This is why a clean work area, tools, hands and removing the game quarter without it touching anything other than the carcass it came off of is important. Then if it gets wrapped with a sterile cling wrap there will be no chance for dirt or bacteria to get on the meat surface and then 3 days later when you're home it will be nearly like you just pulled the hide off. We wont even get into the reason to not open up the guts, which I talk about in a gutless method blog.
No matter what you store the game meat in it will have bacteria. Bacteria is natural and is needed for decomposition or aging of meat. You just don't want it to happen too fast which can take place quicker the warmer it is outside. Leaving a game quarter without any cover over it at all invites bacteria, especially when handling it a lot during a pack out.
The porous material of any cloth game bag also invites bacteria to take up residence. A porous game bag allows air and dirt containing bacteria to always have direct access to the meat surface.
What kills bacteria is cooking the meat to at least 145 degrees. Dead bacteria isn't harmful for you to eat and it does not make the meat taste bad as long as it is not allowed to multiply above certain counts before it gets cooked. You eat living and dead bacteria every day. And your body's immune system needs live bacteria in order to stay healthy. Your stomach and mouth is already full of bacteria. There are more bacteria cells than tissue cells in our bodies. It is only when your immune system gets weakened that allows bacteria (or a virus) to multiply to elevated levels in your body causing illness.
That was a lot to digest so lets take a breath for a moment.
A common argument is that a game bag must "breathe". Though this theory is valid, I am not in that camp as you might have already figured out. And if you are in the "game bag must breathe" camp and are reading this then you are already convinced in your persuasion and will be a difficult subject to convince to use a meat wrap. But I hope you will continue to read anyway and maybe educate yourself on some facts.
As far as a trend I think we might be seeing the beginning of the meat market days. Treating your game meat like they do at the grocery store, nicely wrapped up in none other than good old fashion Saran wrap. And yes, even hot right off the animal in the field. In essence you are simply starting the wet aging process instead of dry aging. Wet aging by the way is a popular method of aging domestic meats where the carcass is sealed up in plastic film. This of course is for weeks at controlled temps in the mid 30s. When the temps are higher the aging process happens much faster, is not as effective, and can result in spoiled meat if not carefully watched.
Deer and elk body temperatures are 101 to 103 degrees, unlike you and I that need to be at 98.6 degrees. The first 3 hours after an animal expires really has no effect on its meat. This is typically when you are parting it out in the field. The next 12 hours is when rigor sets in and the meat begins to break down and things start happening. It takes at least 24 hours for the mass of an elks core, gutted or quartered to cool to ambient temperature if kept off the ground. It may be less for smaller deer size animals and more time for larger such as a moose.
I did a study multiple times on some elk that were killed by my clients. Taking two identical thermometers with me to have when parting out an animal. They had probes that I used to record the core temperature of the rear whole quarters at the bone from the moment after they were skinned. One went into a modern game bag (the Kuiu version of the glorified pillow case) and the other was wrapped in glad wrap.
I recorded the temps in each rear quarter at the bone every hour, with the first reaching around 102 and was about one hour after the animal expired to the time I had the first quarter off, wrapped or bagged then laying on the ground. The other rear came off after completing the first side of the animal and it's temperature was already down to around 100 depending on how long I took getting the first side done. After they were wrapped or bagged I found that they both equally dropped about 1 degree every hour for the first 3 hours and after that they continued to drop equally, increasing the degrees per hour. In fact, after hanging overnight with ambient temps below freezing they both had cooled equally to 55 degrees and the bagged quarter was hanging while the wrapped quarter was laying on the ground. They continued to cool dropping 5 more degrees even while in a panier bag, in the sun and on the side of a horse during the pack out back to camp the next day. From there they continued to cool while hanging in the shade with an ambient air temp of about 50 degrees the day. They never once went up in temperature and the following morning they were all the same temperature at the bone as the average ambient air. This was done on 3 different animals in similar conditions and time frame with similar results.
At a point with one of the instances I decided to take the game bag off the one quarter as the meat was already beginning to dry out and the game bag literally peeled off the meat like duck tape taking some of the meat with it. And of course if when I wanted to re-use that game bag it would require some vigorous washing and would never be as sterile again as plastic food wrap.
This is what stinks about game bags. The meat dries out too much and too fast and as many of you already know that if you let it hang in game bags for just a few days the result can be about a quarter inch of hard dried up crust that you really don't want on the edge of your steak or roast when you butcher. So you cut it off and either grind it up or it gets scrapped.
To combat meat drying out in years past, some have gone the route of using garbage bags which has been frowned upon from the get go and rightfully so. For one, a garbage bag is usually black which of course absorbs heat from sunlight, they are never made of food grade plastic, and some are impregnated with a scent that will taint your game meat immediately.
Do not use garbage bags no matter what color for any game meat. Even if its already in a game bag and you just want to sink it in a creek to cool down. The blood will be in contact with the garbage bag that is not made of food safe material. Horror stories of using garbage bags may have caused a common misconception that using any kind of plastic covering will ruin game meat.
Some have gone the route of Zip-Loc bags that you can get in bigger sizes to fit large chunks of meat from the deboning method. This works to keep the meat from drying out and the bags are fairly tough. They also close off completely, which is fine but if you debone correctly you will wind up with large chunks of meat without the bone which may take longer to cool and you wont cut up the meat too much at that point. If you debone and are using zip lock bags you should drain the blood regularly as the blood will rot faster in temperatures above 40.
Larger chunks will take longer to cool, but it's not because it's not allowed to breathe, which is the argument in the breathable game bagger camp. For those that think the plastic holds heat in and there is not any evaporative heat loss, you can consider this; Even if it does hold some heat in, when you wrap a whole quarter to the hock or knee with cling wrap, then cut the leg off at that point with either a saw or by knife at the joint, the bone would then in fact act as a chimney. This theory might ease your mind some but the other fact of the matter is the same theory goes with a game bag where the bone is exposed. The cling wrap is virtually without any insulation value and with no more heat being produced internally it will only prevent moisture from leaving, any heat then exits through convection heat loss.
And that's another thing to consider when thinking along these lines is a term called "Thermal Coefficient". This is the measurement of the heat transfer of a material, even air. Without getting into the fine and often overwhelming amount of info on this topic I will state that it is well understood that air itself is a poor conductor of heat, so air trapped in many small places with a fiber of sorts in between is a good insulator of heat. This is why you want air to be able to move and dissipate around the outside of the quarter or meat bag.
Think about that the next time you slide your game bag over that quarter actually creating a thin insulation layer. And then think about thin layers of plastic with no air trapped between. Plastic itself does not have the conduction properties like metals. It does however conduct heat, especially when its only about five thousandths of an inch thick after being wrapped around the game quarter. Cloth however will have air trapped within it, and air of course does not conduct heat well creating an actual thin insulation layer.
Saying dead meat needs to breathe is an oxymoron. There is no more blood flow causing friction of blood cells creating heat. Any heat in the animal is leaving through convection of some sort, which can be like breathing but if there is any insulating layer over the meat it will not allow for cooler air to even touch the meat surface so convection is actually inhibited by the effect of trapping small amounts of air within the game bag layer itself. Remember, air if not moving and constantly being replaced, is a poor conductor of heat.
So any heat convection would be occurring through the actual material fibers regardless of it's density. However, over time a more porous material does allow for moisture to escape faster which gets into what called evaporative heat loss. Where the water molecule is actually what caries any heat out of the meat. So this is actually what is happening when using the term breathe. But with regard to a modern game bag, unless you have a garden hose handy and keep the whole bag soaked all the time, this will only happen where there is blood soaked through the fabric. And when the blood soaked game bag and meat surface dries there is no more evaporative heat loss. It goes back to convection heat loss at the dry meat or bag surface. This happens fairly quick with uncovered meat.
On an old cheese cloth type game bag convection heat loss can occur more as there are much larger holes in the fabric to allow for cooler air to actually contact the meat surface and can carry away moisture molecules and thus heat. But these bags notoriously allow the meat to dry out very quickly, and again evaporative heat loss stops. Cheese cloth bags also allow for any contaminates and bacteria to come in direct contact with the meat. Such as large amounts of dirt and even fly eggs, no thanks.
Does plastic wrap prevent evaporation? Lets ask Google...
Answer: "Even though the plastic looks solid, it still allows water molecules to pass through and evaporate."
Does cling wrap trap heat?
Answer: "No, plastic wrap does not have very many qualities that make it an excellent insulator. It may slightly assist in heat retention, but aluminum foil is a better insulator. Two layers of plastic wrap with air in between are the best way to use plastic wrap as an insulator if necessary."
I underlined what I thought were key points. Keeping in mind that if the wrap slightly assists in heat retention the quarter will have the chimney effect with the bone exposed. But even with plastic wrap, any air pocket will become like an insulation spot. Yet once the quarter has cooled below 47 degrees, any insulation spot is negligible and the quarter is much safer from any more bacteria contamination.If you have daytime temps of 65+ and only 45 at night you have 2 days before your game meat should be in a refrigerator. You can add 1 day for every 5 degrees cooler than those high/low temps until below 45 for a high. If it is high's in the low 40s and below freezing at night then you can hang it for up to 14 days or beyond wrapped in whatever. If it is any meat wrap be sure to make a slice on the bottom of each quarter so the blood can drain out. This will help keep blood rot from tainting that area of the meat. When you get it home to butcher, it will be as fresh as the day you pulled the hide off.
I will reiterate this because it is important. If you hang the quarters wrapped in plastic wrap for extended time above freezing then cut a slit in the bottom to allow the blood to drain out. This is so you don't get what is called blood rot. The blood, even though its cool enough, actually rots faster than the meat.
Contrary to popular beliefs, moisture is not really the enemy. It has more to do with the blood, and this is why if you debone you will have to deal with more blood that leeches out of each cut you make through the meat. Elk will bleed out like this much more than deer. When deboning it is very important to use as much natural separation of the meat portions as possible.
I will throw in an excerpt here from a prominent butcher website about storing and freezing meat;
"Large joints of meat such as beef, lamb or pork should be placed in heavy-duty polyethylene bags and then tightly over-wrapped with cling film, ensuring that no air can enter nor any moisture escape."
And that is the whole point of using meat wrap, which is cling wrap, Saran wrap, or Glad wrap. All supposed to be food grade of course. It keeps air (which always contains bacteria) out and keeps more of the meat moisture in.
Taking it a step further lets ask...
What is Cellophane?
"Cellophane is derived from natural sources such as wood, while plastic wrap is made from PVC or Polyethylene. Unlike plastic, Cellophane can't be recycled, but it is biodegradable, so it can be composted or sent to a landfill in the regular garbage."
Is cellophane eco friendly?
Answer: "As a bioplastic, cellophane is 100% biodegradable so it's easy to dispose of – simply put it in your home compost bin and it will easily degrade amongst your other composted items."
So there is a difference between cellophane and food wrap. Cellophane is used more often in the food packaging industry like with candy, and bags of chips. However, Cellophane would not hold up well being used as a game bag as it easily tears. Just think of a candy bar wrapper or bag of chips. Food wrap does tear but it also stretches, though it is not as durable as most game bags, the food wrap still works well.
The main point to all this is getting the insulating hide off the animal to start the cool down process. If you are still skeptical about using cling wrap then you should consider using it after the meat has cooled down overnight to prevent moisture loss and keep air from directly contacting the meat. Also consider that a wrap keeps the flies from getting onto the game bag itself. The worst is cheese cloth when flies are around.
In some households there has been a movement away from plastic food wrap towards a more natural form of food storage using beeswax impregnated fabrics. This is supposed to be a heathier and more eco friendly substitute for plastic food wraps. I have yet to find this material in larger rolls like you can get with food wraps but there may be some validity to sourcing this material for making an eco friendly reusable game bag that won't let the meat dry out so bad when hanging for longer periods.
Finally deciding whether to use a game bag, meat wrap, or hang uncovered should be determined by this. If you will be getting the meat stored in a well shaded spot and the coolest environment possible during the day, it will allow for more time to age or butcher. No matter what, the warmer the day and night time temps are, the faster it will sour. So plan your pack out accordingly.
To conclude, would you rather take home this?
Or this
About the author:
Jamin Florell is 47 and considers himself a proficiently standard outdoorsman. He is a professional hunting guide working exclusively for Medicine Bow Outfitters on Colorado's public land back country for over 20 years. He has been hunting Big Game since he was 10 and killed his first Elk when he was allowed to get an Elk tag at the age of 12. He has hunted Elk every year since then. He has also successfully hunted and guided for Deer, Bear, Mt Lion, Pronghorn, and Moose. He's an inventor, and the proprietor of the Top Hand Tripod.