Venison and Kiwi jerky a stuff up or a success?
Venison and Kiwi jerky investigation of ways to make tender jerky and meat powder as trail food.
Introduction
With an ample supply of fresh venison, I was inspired to make jerky to store some of the meat without using up my freezer’s capacity and to make efficient protein trail food. My previous DIY jerky was made from beef. It was very dry jerky that would keep well without use of added salt (for health reasons), refrigeration or freezing to be suitable as a backpacking/camping food. Although cut thinly and marinated with spices and lemon juice, my first jerky was rather hard and chewy. Although the jerky was very nice, I thought that it could be better if it was more tender.
Venison and kiwi fruit collide
A bountiful lean venison supply coincided with a bumper crop of home-grown kiwi fruit (Haward-green). The fruits were picked while still a little green, to beat the thieving Currawongs to the crop, and they would slowly ripen during cool storage.
“At first, I did not mind sharing the fruit with six or so Currawongs with a cheeky nature and beautiful calls that travel over long distances through the mountains. But 100 or more birds joining the party was just too much. I built a netting cage for the vines. Alas, most of the fruit formed on the fresh growth on the outside of the cage! So green picking and slow ripening during storage was a practical response.”
Kiwi tenderised jerky from venison. Consequently, for my next jerky, I thought that I would try tenderising the venison by using under-ripened green kiwi fruit in the marinade. I knew that kiwi fruit contained protease, peptidease, or actinidin, which is a proteolytic enzyme that breaks down protein and tenderises meats and makes it more easily maserated and digested by us. The same enzyme in pineapple makes it a great adjunct for digesting meals made with pork.
The acidity of the kiwi fruit would also make the jerky safer with respect to selmonella and E.Coli contamination (as discussed later). Acidification of food to be dehydrated is also a great defence against Clostridium botulinum bacteria, which can thrive in neutral to mildly alkaline conditions and produce undetectable and deadly toxins that can cause botulism poisoning.
Note*: Botulism is not a particular high risk with dehydrated foods. However, if that dehydrated food has a neutral or alkaline pH in a moist form before drying and then during preparation for eating, the botulism risk increases. All precautions against forming deadly, invisible and odourless toxins that cause botulism should be taken (hygiene, chilling and acidification and thorough dehydration instead of making soft moist jerky that may have a better mouth feel).
Subsequent cooking may kill the Clostridium botulinum, but does not totally destroy the toxin that it has produced. Clostridium botulinum is a sneaky organism that has spores that lie dormant and are resistant to cooking heat (even pressure cooking), and perversely, that first heat actually stimulates the dormant spores to grow. This is why many non-acidic foods must be pressure-cooked a second time after a rest phase in order to eliminate the risk of botulism poisoning. “In my parents days, DIY bottling or canning of green beans was a no-go risky activity, but salted green beans were a safe alternative, even though I thought the taste was ghastly.”
Back to tenderising with kiwi fruit. During my first tests, I was unaware of the tenderising potency of kiwi fruit, especially when using unripened Hayward-green kiwi fruit, which is particularly rich in the tenderising enzyme. “I possibly should have been a little more aware of this, as both kiwi and pineapple often leave the skin within my mouth feeling a little tender after eating them! Even my fingers become a little tender when peeling dozens of kiwi fruit to make jam.”
So, in ignorance, I did an overnight marination with a generous amount of peeled and pulped kiwi fruit with a little raw sugar and lemon pepper seasoning, as for my previous lemon juice marination of jerky, . “Just as well I peeled the fruit as the protease concentration is much higher in the skins!” I thought, what could go wrong with such wonderful fresh starting materials? I was blissfully unaware that others use a 30-minute maximum marination time with kiwi fruit to prevent the meat from ‘turning to mush’.
First kiwi venison jerky tests
Sliced and minced venison jerky. Additionally, I had noticed that many people use minced meat to make tender jerky. Consequently, I used both thinly sliced and minced venison in my tenderisation tests. “And yes, I did an overnight marination of both!”
Safe dehydration temperature for meat jerky. A post by the USDA details precautions that should be taken with homemade meat jerky. To reduce the risk of growth of harmful bacteria such as selmonella and E. Coli, they recommend rapid and thorough pre-cooking at minimum temperature of 160°F (71.1 °C) before dehydration of the jerky. Most DIY jerky posts seem to disregard this precaution. Perhaps the acidic conditions created by acidic marinades may mitigate some of the risk?
The above post also indicates that this wet high temperature treatment is of particular importance with wild game meats that may have a greater opportunity for contamination and some period of sub-optimal storage temperatures before chilling, processing and preservation.
My Excalibure dehydrator has a maximum temperature of 68 °C. However, this temperature can’t be reached for many hours while the moisture from the meat is causing strong evaporative cooling. Consequently, I decided to do an initial wet heating at 75 °C (or low temperature cooking) of the marinated venison in a convection oven.
To achieve this rapid heating to 75 °C, I put the chilled and marinated jerky meats on oiled metal oven trays and immediately put them into a preheated convection oven that was set to 75C. Then I continued the drying at the same temperature until the jerky was stiff enough to be transferred and flipped onto Teflon dehydrator sheets. Then they were immediately transferred to an Excalibure dehydrator for thorough dehydration at a 68 °C setting. “For the next test, I came up with a much simpler process to achieve the same cooking/killing and dehydration steps.”
Results. Both the thinly sliced and minced venison resulted in very tender jerky. So tender that the jerky strips or flakes fell apart easily. They had ‘melt-in-the-mouth’ consistency when eaten. There was no residual chewiness, unlike my previous beef jerky. The taste was excellent with a hint of fruity acidity from the green kiwi fruit, warmth from the lemon pepper seasoning and overall sweet and slightly salty umami flavour.
Regarding the mouth feel and flavour, the jerky from minced and the sliced meats were indistinguishable from one another. Both had an ‘after-mouth-feel’ of a slight graininess that I later learned can result from excessive tenderisation. To me, this graininess did not detract from the eating pleasure, although it may do so for others.
Discussion. This accidental excessive tenderising could be seen as a failure when making traditional jerky. However, I considered that it made a very edible meat protein supplement that could be eaten on the trail, as is. Alternatively, it can be easily pulverised into a dense and concentrated meat powder for use in making an evening meal when combined with dehydrated vegetables, carbohydrates, and tasty sauces.
I did not record the dry matter yield for these first venison jerky samples, but I make amends in the second attempt.
Second kiwi venison jerky test
To make a more traditional jerky, I considered that the mincing was unnecessary for tenderness. Also, I had already made a test batch of dehydrated venison bolignase with my copious supply of mince that resulted from my ‘rather rusty’ butchering skills. The bolignase is a great success and will be the subject of another post.
This time, I was a bit more quantitative. The 1kg of par-frozen venison was simply sliced* into strips (~6mm thick and across the meat grain of the butchered muscles). Then I used 250g of pulped kiwi marinade and stirred the venison slices frequently during the marination, allowing much of the marinade to infiltrate the meat. The recipe for the marinade is shown below:
Note*. Cutting par-frozen meat allows thin slices to be cut uniformly. However, the ice makes the cutting process more difficult. I tried several knives, but the easiest cutting device was a double-bladed reciprocating electric bread knife. It worked well.
- 250g of skinned and pulped kiwi fruit,
- 4 teaspoons of lemon pepper,
- 4 teaspoons of sugar,
- 4 teaspoons of hickory liquid smoke (I forgot this ingredient in the first test),
- 2 spoons of soy sauce,
- 1 teaspoon of garlic powder and,
- 1 teaspoon of Vegeta chicken seasoning.
This time, the marinated venison slices were put directly onto the Teflon sheet of the Excalibure dehydrator (supported by the plastic mesh sheets). Then they were placed in the convention oven, which was preheated to 80 °C. After ~30 minutes, they were transferred to the dehydrator set at 68 °C.
When the top sides of the venison slices were firm and dry, the Teflon sheet was flipped over on to a mesh sheet. Then the venison was peeled off onto the mesh with the wet side exposed for rapid dehydration. The process was quick and simple, avoiding the messy transfer from metal oven trays, as in the first test. Despite my misgivings, the Teflon and plastic mesh sheets performed well in the 80 °C oven.
Results and discussion. The short marination time (with frequent stirring) resulted in a solid jerky that was tender. It did not fall apart but was somewhat slower to chew up and swallow than the ones from test 1. Large pieces could easily be broken up into smaller ones without any tendency to crumble. The flavour was good and the addition of liquid smoke and soy sauce and other flavourings improved the depth of flavour without being particularly noticeable.
The 1kg of fresh venison yielded 340g of jerky. I rested the dried product overnight at ambient conditions to allow any excess moisture to equilibrate into the drier portion, as is my usual practice with food dehydration. After putting the jerky back into the dehydrator at 68 °C for another 2h the yield reduced to 330g making the yield `33%.
This yield is somewhat higher than I expected, as venison should have 75% water content or 25% dry matter. Some of this extra yield could have come from the marinade, but the 250g of kiwi fruit with a water content of 83% would contribute only 43g+4g of Kiwi+flavouring dry matter, adding ~47g of extra dry matter to the yield. This would make the corrected yield from the venison 283g or 28%. So that is a bit closer to the expected yield. Perhaps the jerky still contains some residual moisture, but it is much drier than regular, softer jerky and should store well.
Most of the 250g of marinade soaked into the meat and became part of the jerky. Out of curiosity, I dried the little pool of residual marinade on a separate tray. It formed an interesting translucent sheet with little scraps of meat and had a delightful flavour. I enjoyed it so much that it was all gone before I thought that I should have weighed and photographed it.
General discussion
The very dry venison jerky was successfully made with either a long or short marination with kiwi fruit pulp using sliced or minced venison. The long marination produced crumbly jerky with a melt-in-the-mouth texture and a slightly grainy after-texture. I expect that it would appeal to many people as a trail-side protein nibble. Being easy to crumble into a powder, it can easily be converted into a meat protein powder for use in backpacking evening meals. The small particle size allows it to rehydrate quickly and pack down densely without any sharp edges that could cut into a plastic storage bag (as was the case with my previous beef jerky).
The jerky made with a short marination has a more traditional texture, but is still very tender and quite easy to eat quickly. Each jerky will appeal more or less to different palates, but both should find great uses as trail food. The addition of liquid smoke and soy sauce to the marinade enhanced the fullness of the jerky taste without dominating the meat flavour. “I’m starting to sound like a snobby wine bottle label.”
For the future, I think I will make more of the ‘crumbly’ jerky as it is simple to make. It is less traditional than chewy jerky, but it is more versatile and a delight to eat in various forms.
Tim
