Thursday, October 31, 2013

Holy Moley Pumpkin Nog

In the interest of full disclosure, we admit that we kind of dropped the ball on our October eggnog recipe.  We meant to celebrate National Pumpkin Cheesecake day with a pumpkin-flavored eggnog.  But we were too busy putting together our row cover chicken tractor, and we forgot all about it.  So, to make up for it, we wanted to belatedly celebrate another October holiday, and one that is observed mainly by dedicated chemistry nerds (including us): National Mole Day.  National Mole Day is October 23 (after the 1023 part of Avogadro's number, 6.02 x 1023, the number of items in one mole of something.  (Just like a dozen means twelve of something.  If you want to know where the number comes from, look here.)  National Pumpkin Cheesecake day is October 21, for no good reason that we can see, other than being in the prime of pumpkin season.  But celebrating two October holidays belatedly equals celebrating one October holiday on time, right?  Anyway, here's how we prepared pumpkin cheesecake-themed eggnog, with the recipe given in terms of moles. (Translation follows below.)

Start with the yolks from 9.96 x 10-24 moles of eggs and beat them until thick and light yellow.  Mix in 18.9 moles of milk (assuming that an average molar mass of milk is around 19 g and has a density of around 1.01 g/mL), and heat to 160 °F.

Add 1.18 x 10-25 moles of brown sugar crystals (assuming a crystal size of 1 mm x 1mm x 1mm and a packing fraction of 0.6), 1.66 x 10-24 moles of cream cheese (since one foil-wrapped 8-oz package is definitely the SI standard unit of measure for cream cheese), 2.24 x 10-22 moles of pumpkin as puree (assuming an average pumpkin diameter of 20 cm and pumpkin core diameter of 10 cm, with the core containing seeds and other stuff) another 18.9 moles of milk, 1.25 x 10-24 moles each of ground cinnamon and ginger (assuming a particle size of 0.1 mm x 0.1 mm x 0.1 mm and a packing fraction of 0.6), and 2.49 x 10-24 moles each of ground allspice and cloves (same assumptions).  Mix in the cream cheese and sugar first so they melt/dissolve nicely, then pumpkin, then milk and spices.

Mix it all together well with the eggbeater.

Wait until cool if possible, and pour into glasses.  (We couldn't wait until it cooled all the way to room temperature).  Serves 0.996 - 1.33 x 10-23 moles of people.  If you expand this up to the one-mole scale, let us know.  Actually, we might be able to tell anyway, because that would probably require every egg in the entire world, and deadly eggnog floods would claim the unsuspecting and those who could not escape up the giant mountain of eggshells left behind.  Although, if one had to choose a way to go...

The Recipe:
9.96 x 10-24 moles of egg yolks (6)
37.7 moles of milk (3 c.)
1.18 x 10-25 moles of brown sugar crystals (0.5 c.)
1.66 x 10-24 moles of cream cheese (8 oz.)
2.24 x 10-22 moles of pumpkin as puree (0.5 c.)
1.25 x 10-24 moles of ground cinnamon (0.25 t.)
1.25 x 10-24 moles of ground ginger (0.25 t.)
2.49 x 10-24 moles of ground allspice  (0.5 t.)
2.49 x 10-24 moles of ground cloves  (0.5 t.)

Beat the egg yolks until thick and yellow, add half the milk, mix well, and heat to 160 °F.  Add cream cheese and sugar, mix well, then add pumpkin, spices, and the rest of the milk.  Pour into 6-8 glasses and serve while telling corny chemistry jokes.  Best enjoyed between 6:02 pm and 6:02 am.

How did you celebrate national pumpkin cheesecake day and national mole day?  Do you think it would be totally awesome to swim in a river of pumpkin-flavored eggnog?  Let us know in the comments section below!

Sunday, October 27, 2013

Squash and Venison

When Mom and Dad came to visit the other weekend, they brought us a wonderful housewarming gift: venison!  It will warm the house when we cook it, and it will make us think the house is warmer when we eat it was part of a hearty meal.  We start craving heartier meals this time of year, and last weekend we concocted something that fit the bill.  If we had washed down the meal with a glass of wine instead of apple cider, we would have been sleeping by 8:30.  As it was, we made it until 9:00, but not much past.  Here's what we did.

To start with, we took a medium-sized acorn squash, cut it in half, and set it in the oven to bake at 350 °F.  That's not what the photo shows.  Katie moves too fast for photography sometimes.  The caption for this picture is 'we started with a one-pound package of venison chops and trimmed off the gristle and excess fat.  Don't forget to save the scraps for soap or biochar!  In addition to the fat and gristle on the outside, this venison had marbling.  Even though we've always hunted agricultural land, we've never seen marbling in venison before.  Either that makes this the fattest deer ever, or we somehow managed to jump a wild guernsey cow from the willow thicket.'
We cubed up the chops and fried them in a bit of butter.  Mr. Smartypants says, "why did you trim off the fat if you were going to add butter anyway?"  Well, Mr. Smartypants, the deer fat was stuck to all the gristle and we were too hungry to spend the time separating them!  Also, Mr. Smartypants, as long as you're here, would you like to add some pepper, cayenne pepper, garlic powder, and salt to the pan?
When the meat was browned on the outside, we took it out of the pan and replaced it with about a pound of chopped kale.  While the meat was browning, we also started a batch of rice.  It's one cup brown rice, half cup of wild rice, and a little over three cups of water.
While the kale and rice were cooking, we chopped up some red potatoes and put 'em in the microwave for five minutes.
When the squash was done, we scooped it out of the shells and added the browned meat with a bunch of seasonings.  There's a little salt, a little pepper, a lot of garlic powder, and some green onion powder, along with a handful of craisins.  We forgot to take a picture of it, but we also mixed this stuff with a white sauce we made from butter, flour, cream, and apple cider.  If we didn't want the squash mixture to taste sweet, we could have replaced the apple cider with milk.
When the kale was wilted, we set it aside and seasoned it with garlic powder and pepper, then added about three tablespoons of olive oil to the pan and added the potatoes, along with a little salt, some garlic powder, and some cayenne pepper.
To finish, we topped the rice with the 'venison-and-craisin-in-squash-matrix and set it on the plate next to the kale and soft-fried taters.  The apple cider washed it down nicely.  Not too bad for a fall Sunday-night meal!

The recipe:
1 medium acorn squash
   1 T Katie's fox point seasoning (scroll down to recipe section)
   1 t garlic powder
   1 t pepper
   0.5 t white pepper (optional)
   0.25 c craisins
1 lb venison chops, trimmed and cubed
   0.5 t pepper
   0.125 t cayenne pepper
   0.25 t salt
   0.5 t garlic powder
2 T butter
 1 lb kale, chopped
   0.5 t lemon pepper
   0.5 t garlic powder
1 c brown rice
0.5 c wild rice
3 c water
6 medium red potatoes, cubed
   1 t pepper
   0.25 t cayenne pepper
   1 t garlic powder
   0.25 t salt
2 T olive or other oil
2 T butter
2 T flour
1 c cream
1 c milk or apple cider

Cut squash in half, remove seeds, and bake at 350 °F until soft.  Scoop out squash meat and set aside.  Brown venison in 2 T butter, season with pepper, cayenne pepper, salt, and garlic powder.  Set aside with squash, Fox point seasoning, garlic powder, pepper, white pepper, and craisins.  While venison is browning, begin preparing rice.  In venison pan, wilt kale, set aside, and season with lemon pepper and garlic powder.  While kale is cooking microwave potatoes for 5 minutes.  When kale is done, add olive oil and potatoes to frying pan.  Season with pepper, cayenne pepper, garlic powder, and salt.  Cover and fry until middle is no longer crunchy.  Check frequently to remove stuck potatoes from pan.  While potatoes are cooking, make white sauce by melting 2 T butter and adding flour to make a thick roux, then adding milk or apple cider, cooking until thick, then stirring in cream, and cooking until thick again.  Add white sauce to squash and venison mix, stir to produce uniform matrix of venison and craisins in squash.  Serve squash matrix over rice, and next to kale and potatoes.  Only serve with wine if no further festivities are planned for the evening.

What's your favorite hearty fall meal?  How do you combine venison and squash?  Let us know in the comments section below!

Thursday, October 24, 2013

Row Cover Chicken Tractor

This is the time of year when many folks who don't have heated greenhouses (including us) are trying hard to eke out the last garden-fresh veggies of the year.  With the frost frequency increasing to 'almost daily', some type of cover over the garden is necessary to keep the crops from becoming a nice sparkly ice sculpture in the early morning but transforming to a mushy puddle of chlorophyll by the afternoon.  So, we built a row cover.  We know, we know.  So what?  Thousands of people have made row covers in the past.  What's special about ours?

As chance would have it, in addition to a garden we want to protect at night, we have a batch of meat chickens we are trying to get on protected pasture during the day.  (We've still been bringing them into the garage at night.)  Since they don't need protection at the same time, we thought we might be able to build something that would serve both purposes.  So our row cover doubles as a chicken tractor.  It's not glamorous, but it is effective, and it has a few features we haven't seen on other row covers or chicken tractors.  So, here's how we made it:

We started by building a frame out of 2 x 4's (10 feet long and 4 feet wide), and cutting two pieces of 3/4" electrical conduit to 6.5 feet long.  If we manage to bend them into a perfect arc, that should give us a two-foot-high hoop at the center of the row cover.  One of four-foot pieces goes three inches in from the end.
We got the hoops kind of the right shape, but not perfect, just by eye and the conduit bender tool you see laying in the frame.  If we wanted to be more precise about it, we could have done something like make a mark every 3" and bend it 6° at the mark, or built a jig.  Marking the conduit would have helped keep the pieces in the coplanar, but our approximation will work for our purposes.
Next, we're going to cut the fence.  We sized it by holding it alongside the hoop and then cutting along the line where the foot is.  We went with the welded wire fence.  It's not quite as predator proof as hardware cloth, but it's a lot cheaper.  It should keep the chickens safe from daytime predators like dogs and hawks.  Remember, the chickens go inside at night so the hoop house can protect the garden from frost!
Hey, this is kind of coming together!  The wire fence pieces add a fair amount if rigidity themselves, so if we get some snow, the plastic sheeting that's going to go over the top will have a harder time falling down and crushing our plants.
Now we need to add a few features to make it more functional as a day-only chicken tractor.  The first is a panel that will slide along the inside to herd the chickens toward one end.  Maybe your chickens are different, but our chickens don't like being picked up very much, so when we go to move them, they run to the far end of whatever structure they're in.  Crawling through a two-foot high wire hoop over muddy, chicken poop-covered ground isn't Katie's idea of a good time, but maybe it could be a new obstacle in the Tough Mudder.  For now, we'll add a sliding panel, which means we need something for the panel to slide along.  We decided to put rails of electrical conduit between the two end hoops for the panel to slide along, and we needed a way to secure them to the hoops.  The punch-out 90° elbows work ok, but we had to drill out one side to get the hoop to pass through.  It would have been much easier with a 15/16" or 1" drill bit, but we made it work with this step bit.  It's not glamorous, but it got the job done.  We found out that holding the elbow piece in a vice or vice grips helps to avoid tearing up our hands when the drill bit catches hard.  We did four elbows (two for each end hoop).
Next we put the elbows on their hoops, punched holes in the conduit, drilled them out, and screwed them to the frame.  Since we were working on an uneven surface, we had to be extra careful about keeping the bottom of the conduit flush with the bottom of the boards.
It's not a great shot, but this shows the hoops and the straight pieces running between them.  The piece hanging in the middle is the backbone of the chicken-herding panel.  It's a piece of 2 x 4 roughly 36" long with a conduit hook on each end so it can slide along the straight pieces.  We'll add a piece of the fencing to it later on.  Below is a close-up of the sliding mechanism.
This is a close-up of the sliding mechanism promised above.  The idea with the sliding panel is that we can push on the board (with attached fencing) from one end with a long stick and chase all the chickens to the end with the door to bring them in for the night.  Then we can push on the board from the other end and give them the space back the next morning.
On the end with the frame's cross-piece set inward a few inches, we added another piece of 2 x 4 to serve as a door so we can let the chickens in and out, and put their food and water in and out.  We bent another piece of conduit for the upper part of the door frame.  So if you're counting, we're at two ten-foot 2 x 4s, two eight-foot 2 x 4s, and five ten-foot 3/4" pieces of electrical conduit.  Plus two 6.5-foot sections of five-foot tall woven wire fence, a hinge, and some screws.
For the ends (the door piece here), we cut two-foot sections of the fencing and attached it to the board...
...then trimmed it a little larger than the hoop and bent the extra wire around it, making sure that the pointy ends don't face outward.  Somewhere along here we've also attached the wire pieces going over the hoops to the board frame.  Same for the chicken-herding panel, but at about 0.8 scale.
We made a little latch to keep the door shut.  It's two screws and a piece of wire we trimmed from the fencing.
Then we added a plastic layer over the top.  It's a 6-mil (0.006") polyethylene drop cloth, 10' x 25'.  That's convenient because 10' is just the length of our row cover!  Wonder if we planned it that way...
We attached it to the rest of the hoop by folding over the end, adding grommets (also our favorite word in the English language), screwing in one side, pulling taut, and screwing in the other side.  If we placed our grommets wisely, we should be able to fold back part of the plastic to uncover a quarter, or a half, etc.  That should help keep the temperature down for the chickens if it's sunny and warm during the day.  We're not sure how long the grommets will last, but we'll update the post if they tear through quickly.
Looks like it's ready to keep the frost off our kale!  Too bad not much else is thriving in our late-planted fall garden.  We're just making it easier to have next year be better than this year!  We haven't figured out an aesthetically-pleasing way to do the ends just yet.  A little bit of internet research suggests that most other folks haven't either.  We didn't want to take a lot of excess plastic and bunch it up.  Maybe we'll do something with reclaimed boards after a while.  For now, we'll drape a couple tarps over the ends at night if it's going to be below 25 °F or so.  Not aesthetically-pleasing, but it'll be dark outside, and we'll be out at dawn and dusk anyway to transfer chickens.  We'll keep working on it and update this post when we figure something out.
And here it is with chickens!  They're busy getting next spring's garden expansion ready.  Heck, we might need to make a second one this fall if the chickens get any bigger!

Have you built any dual-purpose row covers?  Do you have any good ideas for how to do the ends?  Let us know in the comments section below!

Sunday, October 20, 2013

Biochar from Butchering Waste

One thing that's been on our minds lately as our chickens rapidly approach the age at which they are released into our small, electrically-cooled pasture is, 'what do we do with the butchering leftovers?'  Growing up, anything leftover from meat-processing or meat-eating operations went out into the open field or out in the woods, just far enough away that the dog wouldn't find it and regurgitate it in the living room.  Sometimes the dog did find it anyway, and if that happened, Dad decreed for the next several batches of meat-related waste that it needed to be taken twice as far and buried at least ten feet deep.  Our impression is that this approach is followed by many other folks, as well, with many variations on the theme.  Cheap and easy?  Definitely.  Sanitary or good for keeping coyotes and raccoons away from your chickens?  Not so much.

On the other hand, if livestock are taken to the local meat market for processing, the guts and feathers and other stuff that doesn't make it to the plate are often hauled away at cost to the butcher, to be rendered into soap, glue, and food for future generations of livestock.  Although that's been changing (especially abroad) thanks to Bovine Spongiform Encephalopathy (BSE, or mad cow disease), dealing with slaughterhouse waste is still a big problem.

Cornell University has a good article discussing different options for taking care of this waste responsibly.  Both economically and ecologically, composting emerges victorious, but there are several considerations that must be taken into account for a favorable outcome.  The first is to have a site available that is well-drained and 200 feet away from any surface water source.  The second is to have lots and lots of high-carbon organic matter (such as wood chips or sawdust) available.  The third is to not have any neighbors that object to the smell if you plan to turn the compost pile in the first 3-6 months.  We're 0 for 3 on that checklist.

In the past, we've had some success with using worm composting to decompose meat-processing waste.  But, like standard composting, precautions must be taken to eliminate odor, including the use of a lot of bedding above the waste.  Also, there's no way our current worm bin size could handle the leftovers from processing seventeen chickens, and we don't know how the vermi's would do with feathers.

Then, earlier this spring, an interesting article, Biochar of Animal Origin, came out in the academic literature about processing butchering waste into biochar for use as a soil amendment.  In particular, the authors focus on the use of animal-bone biochar as a replacement for phosphate rock fertilizers (which are the current phosphate source for most of the industrial agriculture system).  The article is set in the context of averting peak phosphorus (phosphate rock is a rapidly-depleting non-renewable resource), mitigating fertilizer runoff from large-scale fertilizer misapplication, and reducing an industrial waste product (animal bones).  None of those problems may seem particularly pertinent to homesteading-minded folks, but many homesteaders both generate animal-processing waste and make biochar from wood as a soil amendment.  It seems that converting meat-related wastes into a useful product like bio-char would be a permaculture-consistent, hygienic way to process them, even if one did have the space to drag the bones, gristle, and feathers half a mile and bury it ten feet deep like Dad said.

Why would one want to make biochar, other than to get rid of a waste product?  There are a lot of good resources out there on the internets explaining the benefits, but we recommend checking out Anna's lunchtime series on biochar over at the Walden Effect and Shaun's discussion of the matter over at Shaun's Backyard as a good starting point.  Briefly, biochar improves soil nutrient-holding capability (via ion exchange capacity) and texture, and has a porous structure that houses beneficial bacteria.  The bacteria in turn further increase nutrient availability to plants, in part by producing metabolic products that break down the biochar itself (but the carbon base pretty much stays put).  For example, the sciencey paper linked above discusses inoculating biochar with bacteria that produce acidic metabolites, which make the phosphorus in the biochar soluble (and thus available to plants).

Here's a scheme of how animal biochar could fit into a homestead's operation.  Here's a riddle: what becomes naked as it gets dressed?  A chicken!

We haven't tried making biochar yet, but we're working on a biochar retort/oven that we'll hopefully be able to report on in a few weeks.  In the meantime, how do you dispose of your meat-related wastes?  Have you made biochar on a small scale?  Have you made biochar from anything meat-related?  (Other than accidentally burning steaks on the grill.  That doesn't count unless you used then used the char for something useful.)  Let us know in the comments section below!

Sunday, October 13, 2013

Chicken Update: One-Chicken Run

A couple weeks ago, we noted that one of our chickens was having balance problems, but appeared otherwise healthy.  We posted our solution at the time, which was to house the chick in a padded flower pot where it could still reach food and water, but wasn't in danger of being trampled by the other chicks when it fell and couldn't get up.  The chick quickly outgrew the flower pot, but was still having balance problems, so we had to come up with a new solution.  Enter the one-chicken run.  The chick can stay upright, as long as it has supports on either side to keep it from falling over.  So we build a little rig to house the chick.  It's just like bumper bowling, but with a chicken-flavored bowling ball.

Here it is!  Ta-daa!  It's just a few pallet boards screwed together with one over the top to hold food and water dishes.  Hopefully they won't tip over as easily as they did in the previous iteration.  The boards are about 6" tall.  The brown sheet on the bottom is a piece of textured rubber stuff that's normally used to pad table tops from lamp bottoms and prevent scratches and sliding lamps and stuff.  The plastic bottom is too slippery for chicken feet to grip.
Here it is with shavings and the food and water dishes in place.  Now it just needs a chicken!
Looks like he figured it out.  We were seriously considering culling this one since it hasn't gotten better over the last three weeks, but it's still eating as much as it can and is still growing, albeit slower than the other rangers.  So, we've decided to keep it going until we notice a significant change in its digestive habits.  It might not be as big at butcher time as the others, but will probably still be worth the effort.  Part of the reason for the slow growth might be that it frequently tips over its food and water.  Whenever we check on it and set it back up, it seems hungry and thirsty.  Hopefully this new chicken-and-victuals-balancing device will help keep the bowls steadier.
We built it to fit in the skybox tote, but it also works to have it free-standing, as long as the chick still has access to the food and water.  The end with the bowl holder can maybe provide a little shade if it's positioned strategically.  It seems to be enjoying the buffet.
Actually, we could probably do away with the skybox if we set it up like this in the regular brooder box, but we've run into a couple issues that might make that problematic.  One issue is that the chick can still escape if it really wants to, so we have to check on it a lot to keep the other chickens from picking on it.  The other is that, as shown in this picture, the other chickens seem to enjoy hopping up on top of it and hanging out.  Sometimes they step on the chick inside, and if they were to sit up there for an extended period of time, there's a good chance they could end up dropping a load of fertilizer on the chick inside.  So, this works if we can keep an eye on things, but for overnight, the skybox is probably still a better option.
The chickens will be five weeks old tomorrow, which is halfway through their expected life span this fall.  Some of them have pretty good heft already, and they feel pretty meaty when we pick them up to move them outside and back.  We estimate that the biggest one is probably around two pounds, and the smallest one (other than Gimpy or the gray one) is probably about a pound.  We've gone through almost two fifty-pound bags of feed to this point, so if the chickens have an average weight of 1.5 pounds and there's 15 of them, that makes 22.5 pounds of chicken for about 90 pounds of feed.  That's a conversion ratio of 4:1, which is in the range we're expecting.  Cornish cross broilers are often quoted as 2:1, other rangers can vary between 2.5:1 and 5:1 or so.  It's been fairly cold at night, and they're still filling in their adult feathers; hopefully they'll fill out a little more in the next five weeks!

Do you have experience with the red ranger broilers and their feed conversion ratio?  How have you helped a chicken with balance problems get back on its feet?  Let us know in the comments section below!

Tuesday, October 1, 2013

Turning Grease and Trimmings into Lard, Cracklins, and Soap

NOTE: This is a long post and is way too technical at times.  We should have probably broken it up into two posts--how to render lard/tallow and then how to make soap out of it.  But we wanted to keep the whole process in the same place, as a single reference.  Hopefully some of our readers will appreciate the thoroughness.  If you are not one of those readers, apologies in advance.

Last weekend, we wrote about saving our bread crumbs in the freezer to turn into schnitzel.  We do a similar thing with our meat trimmings and leftover frying grease, and bacon drippings.  Except we don't make schnitzel out of them.  We make cracklins and soap.  Very little goes to waste, and if we had dogs, none of it would!  It's a many-step process, so let's get started.

We started collecting meat trimmings and leftover grease in canning jars in the freezer.  When we decided we had enough for a good batch of soap (which was this weekend), we thawed them out.
We sped up the thawing process in the microwave.
After two minutes or so, the trimmings are liquidy enough to scoop out of the jars and into a single bowl.
We added a few cups of water to the mix.  The idea is to get everything liquid, and impurities in the fat will settle down into the water layer.  Another five minutes in the microwave and a lot of the fat is melted, but a good portion of the trimmings are still solid.  That's ok for now, it just means that they had a lot of either very high-melting fats or non-fatty material.
A second five-minute stint melts quite a bit more of the fat, and with that, we'll set it in the fridge and let it cool down.  With the light shining from the top, it's easy to see that most of the impurities have gone into the water layer and the fat left on top is nice and clear.  Yay, we're rendering!
After a few hours the fat is what amateur scientists might call 'recrystallized'.  It's pretty white, but there are still some brown things in the fat. 
So we'll scoop most of the fat into another bowl (left) and discard the water (gasp!).  If we had a dog, we'd give it the water as a treat.
We switched the fat back to the other bowl, added more water to the scooped out fat and microwave it again for 5-10 minutes.
More of it is melting, and some solid specks are visible at the bottom of the bowl.
Then we take it out of the microwave and scoop out any big pieces of solids that haven't melted yet.  These must be things mostly not fat (or really high-melting fat).
Now we've got one bowl of slightly-less-fatty solids and one bowl of clean fat on top of dirty meat-water.  The second bowl goes back into the fridge to solidify the fat again.  After that, we'll get rid of another batch of water.  What a lucky imaginary dog we have!
The first bowl goes into the frying pan to make cracklins!
We let them cook down for a few hours.  Some additional fat will melt, and the rest will fry down into a tasty toasty batch of delicious.  Some folks recommend not making cracklins in the indoor kitchen because the whole house will smell like cracklins and they will splatter oil everywhere.  We're not sure why the first reason is bad, but we went with a low heat and didn't have much splattering or odor.
Here they are cooked down, stewing in a delicious bath of their own making.
We drained off the fat into the other bowl and stirred it up a little bit to make sure any non-fat parts of the cracklin grease get extracted into the water layer.  (If upon solidifying, impurities in the fat layer are still visible, you can do another step of removing the water, adding clean water, melting everything again, and removing the water.  Hopefully your dog has been really good.)  Then we seasoned the cracklins (a few sprinkles each of salt, pepper, garlic powder, cayenne pepper, and Tabasco sauce), then took the spoon and broke up the cracklins into small pieces (after trying a few, of course).  We use the pieces like bacon bits.  We're eating ours on chili this week. They are not healthy, but they are good.   Everything in moderation.  Mmmmm.
We'll need to know the weight of our purified grease, so we're going to start by weighing our now-empty bowl.
...And now with the fat in it.  Some folks use this grease (mostly lard for us) as a foodstuff largely equivalent to modern-day vegetable shortening (after it solidifies).  Lard has gotten a bad rap as being unhealthy, but actually has a healthier lipid profile (less saturated and more unsaturated fat) and lower cholesterol than butter.  (According to Google anyway.  How does Google know this stuff?)  It's certainly not a health food, but to dismiss it as less healthy than shortening or butter isn't fair, either.  (Keep in mind that lard rendered this way is likely better than store-bought lard, which has often been hydrogenated just like shortening.)  Anyway, we've got more of a need for soap than pie crusts for the time being, so we're going to turn our lard into soap.  The following process is what's described as cold-process soap.

At this point it's probably a good idea to review the soap-making process.

<chemistry-dense section>
Lipids such as vegetable oils, beef tallow, and lard, are made up of triglycerides, or TGs.  TGs are made up of a glycerol 'backbone' and three fatty acid tails (the tails are often abbreviated R or R' or R'' by lazy organic chemists).  Saponification breaks the tails off the glycerol backbone using a basic reagent (normally NaOH or KOH), which forms glycerol and a fatty acid sodium (or potassium) salt (i.e., soap).  Each type of lipid (and even the same type of lipid from different sources!) has a different fatty acid profile in its makeup (some of the tails will be longer or shorter, or have different numbers of double bonds (which makes them 'unsaturated').  Because the the oil and base react on a number basis and not on a mass basis, therefore, an ounce of different oils will require different amounts of base to react fully into soap.  This feature is reflected in a characteristic called the saponification number, or SAP number for short, which is formally defined as the mass of potassium hydroxide (KOH) in milligrams (mg) required to fully saponify one gram of a given oil.  These numbers will typically be in the 100-200 range.  Many times, however, SAP numbers are reported as 'grams per gram' or 'ounces per ounce', which are different by a factor of 1000 (they'll be in the 0.100 to 0.200 range).  SAP numbers are tabulated in many places, including online (of course), and many tables give a range, or give values that differ from other tables because of the inherent variability of an oil type's chemistry.
</chemistry-dense section>

An example of how a SAP number is calculated from an oil's composition is given in the spreadsheet linked here.  The spreadsheet also shows how to use the SAP number to make a soap recipe for a given fat composition.

Anyway, we estimated that our fat was about 70% lard, 15% beef/venison tallow, and 15% olive oil, and we had 21 oz. total.  That means we had 14.7 oz. lard and 3.15 oz. each of tallow and olive oil.  The SAP values for those are 0.138, 0.140, and 0.134 for NaOH, respectively (it would be different for KOH), which works out to 2.89 oz. of lye to fully saponify the fats (multiply the amount of fat by the corresponding SAP value and add them together).  Normally, a 'lye discount' is used to leave a little bit of the fat intact.  That makes the soap less harsh.  We took a lye discount of 9.5% (requiring 2.62 oz. lye), which is pretty high.  But we know that the cooking process itself will start to break up the triglycerides, and used cooking oil will often contain ~5% free fatty acids (i.e. material that doesn't need lye to become soap).  So we eased off on the lye to account for those as well.

Where do we get our lye from?  We found what we were looking for in a certain type of drain cleaner, but we had to be careful that it says 100% lye or 100% sodium hydroxide on it and is white in color.  Other ingredients might interfere with the saponification, and might be dangerous to clean yourself with.  (Unless you're a drain pipe.  If you can read this, you're not a drain pipe.)  Soapmaking and biodiesel sites can also be good resources for where to find good-purity lye (or make your own!).  It's important to have a good soap recipe.  There are plenty of good links on the internets, but we like a ratio of about 6 oz. water per 16 oz. fat, and lye according to the saponification (SAP) number, minus the lye discount.  Also, for our lye, which is in granulated form, we found that one ounce of the granules equals 1.814 tablespoons (by weighing a half cup and dividing by eight).  The small amounts are easier to measure by volume in a tablespoon than by weight on our mechanical kitchen scale.  The density used to be less than that--this lye is a couple years old and lye in general is hygroscopic, which means it will take on water from the atmosphere.  That can affect your measurements, so make sure to keep your lye tightly sealed.  In effect, we're actually taking a larger lye discount than we calculated above because some of the 'lye' we're weighing out is really water.  But in our case the water content hasn't changed too much, so our calculation will still work.  So our final recipe is 21 oz. rendered fat, ~1 cup water, and 2.62 oz lye.  SAFETY NOTE: All steps with lye should be done wearing rubber gloves and goggles!  If any lye or lye solution gets on your skin, rinse it off right away with lots of water.  Don't let any get in your eyes.  That would be very bad.  If it does, flush with lots and lots of water and get to a doctor.
We mixed the lye and water.  Add lye to water, not the other way around, or the first water you add could get superheated and pop, sending caustic ooze flying around the kitchen.  Caustic ooze makes Katie unhappy, especially in the kitchen.
It will get hot.  Normally hotter than this.
When it cools down a little (to ~110 °F or so), we added the lye solution to the fats and stir.
We keep stirring until the soap 'traces.'  That means the spoon stirring through the liquid will leave a visible trace (or something like that).  Anyway, when it's the consistency of warm molasses, it's traced.  In chemistry terms, that means the saponification reaction has gone far enough that the fat and the water we mixed together won't phase-separate anymore, and we can pour it into our soap mold. (Oh yah...we need to build one of those...)  Before we do that, though, we add any other ingredients we might be thinking about--little pumice scrubber things, girly herbal things, or something to make the soap lather better, because standard soap molecules by themselves don't make much for bubbles.  Castor oil is commonly added to increase lather, but we didn't have any on hand.  Why does castor oil work well?  Because the fatty acid chains have hydroxyl groups on them, which interfere with water's surface tension.  (A bubble's film needs an optimal viscosity-to-surface tension ratio and a slow water evaporation rate to be stable, and the hydroxyl groups in castor oil move the soapy water's properties closer to that optimum, mainly by reducing water's surface tension via disruption of it's hydrogen bonding network.)  So, what if we added something else with hydroxyl groups?  Like sugar or honey--it will work!  We added about 1.5 tablespoons of honey at trace.  Katie likes bubbles.
A glass dish like this functions ok as a makeshift soap mold.  This will be the final shape from which we cut our soap bars, so we have to make sure it's nice and smooth.
That's better.
After sitting for a few days, and it will become nice and solid.  After a week or so, we'll take it out of the pan (hopefully in one piece), and cut it into bars.  It will need to cure for another month or two before it will make good soap.

UPDATE 10/4/2013: We cut it into bars and it's now curing.  Here's some pictures:

After a few days, the soap should be solid enough to take out of the mold and cut into bars.  We used a flipper/spatula thing (the device used for flipping hamburgers or removing cookies from a cookie sheet post-bake).  We got lucky this time and the soap all came out in one big, chic-looking piece.
Then we cut it into bars and spread it out on a plate so it will cure faster.  Also, to teach a lesson to any hungry burglars thinking we have a plate of cheesecake bars or something on top of the fridge.  Don't forget to brand the bars, if you're into that kind of thing.  We'll leave it like this for 6+ weeks, though others say it would be fine to use sooner.
Then we washed the soap mold.  Guess what!  We didn't even need to add soap!  That must be the cleanest dish ever.

Do you have other soap-making tricks?  Have you ever done it with wood ashes as your lye source?  What else do you do with scraps from your meat-trimming operations?  Let us know in the comments section below!