There’s no greater satisfaction in life than bringing home freshly harvested meat for your family. For many of us, this calling will lead us blindly into the great outdoors, and drive us to contend with Mother Nature and the elements in the pursuit of this goal. The taste and the quality of your meal will far exceed anything that you can buy in-store. Still, what if I told you that it could taste even better?
In this three-part series, I discuss how you can improve the quality of your harvest. In Part 1, I’ll provide you with an overview of bacterial contamination and growth. This includes a list of ways to reduce the risks associated with it. Part 2 will contain information on how to maximise the quality of your harvest – from the field to your plate. Lastly, in Part 3 I will look at long-term meat storage. This includes the packaging, freezing, and the thawing process.
This is part 1 of the series – Bacterial contamination and growth. Before we can learn how to avoid it, we first need to understand the science behind the chemical breakdown process and the role that bacteria play in it.
The science behind the chemical breakdown process
After an animal has been dispatched, the oxidization process begins to occur within the body. This is due to the interruption of blood flow and metabolic processes. As the oxygen reacts with unsaturated fats, it causes a series of chemical reactions which produce the tell-tale signs of spoiled meat – rancid odour, odd textures, and a poor taste in the muscle and fatty tissue of the animal.
In the early stages of oxidization, the enzymes that are present inside the muscle will convert the remaining stores of glycogen into lactic acid. This lowers the pH value and causes stiffening of the muscles, or rigor mortis. On average, this process will occur two hours after death and will last for a minimum of 24 hours. Once the glycogen is completely used up, the muscle stiffness will decrease and the pH level will rise – marking the end to rigor mortis. At this stage, the enzymes will start to break down the protein and fat. This can be a positive for game meat, as – if properly handled and stored, the meat will begin to “age” or tenderise. Unfortunately the same can not be said for most species of fish and other seafood, as aging the meat will cause it to slowly degrade, and eventually putrefy.
Throughout the chemical breakdown process, the by-products created by these enzymes will act as a form of nourishment for any bacteria that is present in the meat. To produce more of this feed material, the bacteria will secrete additional enzymes into the meat, thereby creating a rapid cycle of growth between the enzymes and bacterial organisms. This cycle of growth should be viewed as the rapid deterioration of the quality of your meat. That’s why it’s important to minimise the introduction of additional sources of bacteria, and why it’s important to maintain the appropriate storage conditions that will stunt the growth of bacteria. The more careful that you are, the greater the chance you will have at preserving a higher-quality, and longer-lasting end product.
How does bacterial contamination occur?
Bacterial contamination will occur if your meat comes into contact with any source of internal or external bacteria. Internal sources include the gills (fish), or the intestines and bodily cavities of ALL animals. External sources include the slime (fish), the hide (or hair) on game animals, and any other external carrier that may come into contact with the animal’s body. The most common offenders are; water, soil, the hunter (or angler), and their butchering equipment.
While the introduction of bacteria can never be fully prevented, good hygiene practices and proper storage conditions can drastically reduce the rate of growth.
How to reduce bacterial contamination and growth
The following list contains several methods that will greatly reduce your risk of bacterial contamination and growth. This list is by no means exhaustive, meaning that other options may be available, and these options may also provide you with some protection against bacteria. As with all things – consider doing your own research, and find a solution that works best for you.
Storage capacity
This may come across as a bit of a ‘no-brainer’, but I see it happen far too often for me to leave it off the list. Before heading out in the field, you should always make sure that you have enough storage capacity on hand to preserve your targeted species of animal.
If you’re just entering the world of fish and wild game, you may be a little unsure of just how big, ‘big enough’ is. In these circumstances, I recommend that you always lean towards the side caution, and go with the ‘overkill’ storage option. After all, it’s better to take up that extra room in your vehicle, than it is to waste your hard-earned fish or game meat due to an undersized refrigerator or esky.
Cooling capacity
Plenty of storage is a wonderful thing. However, if it cannot cool down your meat, you’ll be in for a world of heartache. That’s because bacterial growth is accelerated in warmer conditions. Ideally, the temperature of your esky or refrigerator should sit between 0° – 4°C. This temperature range will impede bacterial growth and ensure that your meat remains as fresh as possible.
If you plan on heading out in the field for an extended period, the condition of your ice or batteries should be monitored regularly to ensure the appropriate temperature is maintained. The last thing you want to discover after a long journey is the pungent surprise of spoiled meat.
Improve the lifespan of your ice
We’ve all experienced the disappointment of opening up our esky on a warm summer day, only to find that our food and beverages are now submerged in an icy pool of water. Despite the advertised ratings for ice retention, many of us are aware that it will never last as long as we had expected. So, what can be done to improve the lifespan of your ice? The answer is simple – pre-chill your esky.
When ice is added to a warm esky, it will quickly melt away as it begins to lower the surface and air temperature inside the container. Pre-chilling ensures that when your bagged ice is placed into the container, it enters an environment that’s already down to the appropriate ambient temperature, thereby increasing its usable lifespan. The best way to achieve this is by placing frozen water bottles inside your esky the night before your trip away and allowing it to reduce the temperature overnight. Before heading out the next morning, simply switch the bottles out with some fresh bagged ice, and you’ll be ready to head out on your next adventure.
Chill your meat down IMMEDIATELY after harvesting an animal
Bacteria thrive in warm and humid conditions. Chilling your harvest as soon as possible will stunt the growth of bacteria, and ensure that your meat will last longer, and taste better.
Avoid contamination from hair and bodily fluids
Bodily fluids, such as stomach bile, urine, and the chemical pheromones produced in scent glands (game species) will not only impact the flavour of your game meat, but they will also introduce bacteria. Learning proper butchering techniques will help you to avoid any potential contamination, and greatly reduce your risk of having poor quality, or “gamey” tasting meat. Most approved hunting organisations (AHO’s) will run butchering classes throughout the year to teach this skill set. Alternatively, you could ask your local butcher to see if they’re willing to guide you through the process, in exchange for money or time volunteering around their shop. If neither of these options is available to you, there’s a wealth of information available on YouTube that can teach you the basics of butchering an animal.
Do not allow game meat to become submerged in water
Contact between your meat and any source of water should be avoided wherever possible. This includes the water in the bottom of your esky. The easiest way to accomplish this is to crack open the drain plug on your esky and allow the cold water to trickle out as the ice melts away. Alternatively, you may opt to use a rack to elevate your meat above the water level and drain it out intermittently. Either option will prevent the rapid deterioration caused by water-born bacteria.
If you find yourself in a situation where your meat requires cleaning – i.e. due to excessive hair and dirt on game animal meat, your best option will be to wipe it down with a moist paper towel. Remember, this should always be followed up with a ‘pat’ down with some dry clean paper towels to remove any build-up of excess liquid on the surface of the meat. Some hunters may go one step further and rinse their meat off with fresh water. However, I would caution against it. As with all things in life, this is a judgement call that you will need to make on a case-by-case basis.
Avoid cross-contamination
Cross-contamination is the transfer of harmful bacteria from one source of bacteria to another. The way to avoid this is simple – Always ensure that your hands and butchering equipment are kept clean and dry. This includes knives, meat bags, cutting boards, and any other object or surface that may come into contact with your meat. Cleaning should always be done with hot soapy water, as this will kill any remaining bacteria that may be present in the area. Cross-contamination will also occur if cooked and uncooked meats come into contact with one another, or if meat from two different species of animal contacts each other. For this reason, you should always plan ahead, and exercise caution when handling multiple types of meat. Food poisoning is not a pleasant experience. Trust me, this is not a lesson you want to learn the hard way…
Remove and discard any meat that is bruised, contaminated, or questionable
Some meat isn’t worth being salvaged. This includes any meat that comes into contact with stomach fluids and urine or contains bullet damage and bruising. While it may still be technically ‘edible’, I can guarantee that it will reduce the overall quality of the meal that you intend to prepare with it. So take the loss, and use it as motivation to improve your shot placement and/or butchering techniques for future harvests.
Final thoughts
Bacteria can have a catastrophic impact on the quality and lifespan of your fish and game meat. However, with a little care and planning, you can greatly reduce the impact that it may cause. Stay tuned for part 2 of this series – where I discuss how to maximise the quality of your harvest – from the field to your plate, and how to spot early signs of decomposition.
