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I can feel it. This is going to be one of those all-out, no-holds-barred, balls-to-the-walls type years on Thanksgiving day. No compromises, no shortcuts, just the best, tastiest food I can possible make. When it comes to turkey, for me that means working in parts. Now, we've already made great use of the breasts-minus-the-tenderloins with this porchetta-style turkey breast, I'll be braising the legs in red wine on turkey day, and I'll be using the carcass to make a turkey stock for my gravy. Which leaves me with only the sad, lean, skinless tenderloins to deal with.
When life gives you lemons, you make lemonade. And when life dumps random fleshy bits of animal protein on your cutting board, you make sausage. Doesn't it sound so appealing when you say it like that?
How about if we say that we're going to take that otherwise lean, bland, and generally dry turkey tenderloin and transform it into something deeply seasoned, snappy, and juicy? Better?
Good. Let's get going.
As a relatively mild meat, turkey is best used for lightly spiced, brightly flavored sausages. Weisswurst, the German sausage flavored with lemon zest, mace, and parsley, fits that bill perfectly. It's a smoothly emulsified sausage (i.e. more hot dog than Italian sausage), which means that it takes a little more care to get right, but in the end is easier to produce using home equipment—no meat grinder or sausage stuffer required! All you need is a food processor and a piping bag with a smooth tip.
Before we begin, here's a quick pop quiz: What's the most important ingredient in a sausage? Let's take a look.
Sausage and Salt
I'm going to cut right to the chase here and let you know what the most important ingredient is in sausage: Salt. Plain old sodium chloride. You may think of salt as merely a flavoring agent, something that makes french fries and steak taste good, but its effect on meat is far more profound than that—anybody who's brined or dry-brined a turkey can tell you that.
Want to see a demonstration of the drastic difference salt can make in a a sausage?
I ground up two batches of pork, both cut from the same shoulder, both identical in every way. The first was seasoned with a 2% salt mixture and allowed to rest for 8 hours. The latter was left completely unseasoned. I ground both of them in a meat grinder, formed them into balls, then poached them in 180°F water until they reached an internal temperature of 160°F before cutting them in half. Check out what happened:
You can plainly see that while the sausage on the left held together with a smooth, resilient texture, the sausage on the right completely crumbled, much like an overcooked burger.
In their whole form, muscle fibers resemble thick bundles of telephone cables, where each individual wire inside the bundle is a single protein. Chop up these cable bundles, like you do when you grind meat, and you end up with a whole bunch of shorter bundles.
Even if you mix them thoroughly, you'll only succeed in some very minor cross-linkage between these short proteins—Not enough to create the bouncy, tightly bound texture of a sausage or to improve its moisture-retention capabilities.
Salt changes everything.
When you add salt to meat, it first dissolves in the juices that it extracts via the process of osmosis, creating a salty brine. Then, certain meat proteins, namely myosin, partially dissolve in the presence of this brine.
Essentially, the bundles of telephone wires become looser, their ends fraying out. Just by feeling a chunk of salted ground meat vs. regular ground meat, you can instantly tell the difference: the salted meat is much stickier and thus forms bonds better when you mix it.
Indeed, the longer you let your meat rest after salting and before mixing, stuffing, and cooking your sausage, the better its moisture retention abilities become. I cooked eight batches of sausage in an identical water bath, each salted for a different range of time starting with immediately cooking after salting all the way up to salting 24 hours in advance. I measured the moisture loss of each. Here's what we see:
As you can see, there's a pretty clear advantage to letting your meat rest before grinding and forming the sausage. A wait of two hours saves you half of the juices that would have been lost, while four hours saves you a full 75%. Not bad. Beyond eight hours or so, the changes become incremental, shaving off a half percentage point or two before finally maxing out at around a 3.6% moisture loss level after a few days of salting.
Tl;dr version: When making sausage, salt your meat well in advance of mixing it! 1.5 to 2% salt compared to the mass of the meat is a good ratio for proper sausage binding (use a scale!).
Fat and Lean
When I asked you what the most important ingredient in sausage was, a good portion of you probably cried out, "The meat!" causing co-workers, spouses, and/or pets to wonder exactly what it is you do on that computer all day. That's a good guess, but it's wrong. See, good meat? Well, yeah, it's important, but a sausage can be made out of pretty much any type of meat. Pork, duck, turkey, beef, chicken, venison, even fish or scallop. You name it—if it's got muscles and fat, it can be turned into sausage.
Fat is also important—without it, a sausage will lack juiciness (true story: fat is more important to triggering our sensation of juiciness than water-based liquids. Fat makes things taste juicy. Water makes things taste... watery.) It will also lack robust flavor, since many of the fat-soluble flavor compounds in animal matter and other seasonings won't have good vehicle through which to reach your taste buds.
When forming a sausage, the exact proportion of fat to lean can have a profound effect on the finished product: too little fat, and your sausage will be dry and flavorless. But go too far in the other direction and you run into other problems.
See, as fat cooks, it softens and liquefies. It has a tendency to leak out of a sausage. Now, if your sausage is properly made (and we'll go into more detail on that in a bit), it'll consist of a tight matrix of cross-linked proteins that form a sort of net, reining in all the juices and melting fat that wants to escape. But there's a limit to how much it can hold—for an emulsified sausage, that limit is about 35% fat.
I made a sausage with a fat content of 42% to demonstrate:
See how that fat glistens like ocean water off of a breaching orca's back? That's not a good thing. The sausages were overly soft and greasy.
Think of the sausage like a pint glass you're filling with beer. The more beer you have in it the better, but you don't want it to spill out and make a mess. Similarly, for the juiciest, most flavorful sausage, we want to fill it to its brim with fat, which in this case happens to be about 35%. It'll give you something like this:
The sausage is moist and juicy, without any of that juice spilling out. And before you even start, nobody said this was health food. (Yes, I'm looking at you)
Your choice of fat is almost as important as its ratio. Poultry fat, due to its relatively low proportion of saturated fats, is relatively soft. It's difficult to get it to emulsify properly and it liquefies at very low temperatures, making it a poor choice for sausage. On the other extreme, ruminant animal fats like beef and lamb are loaded with saturated fats, which make them hard and waxy, even when you heat them. A sausage made with too much ruminant fat will leave a greasy, heavy coating in your mouth.
When it comes to sausage, pork fat is king. It has a nice clean, neutral flavor, and softens and melts at just the right temperature to make it easy to work with, without feeling heavy on the palate. Have you ever noticed that most chicken and turkey sausages either have pork fat in them or wind up tasting dry? That's why.
For this style of emulsified sausage, I like to start with pre-cured salt pork; the curing makes it easier to emulsify properly down the line. It also makes it saltier and a little firmer than we'd like. A brief trip into a pot of boiling water (to which I also add some onions to get rid of their raw edge) solves both of these problems.
Tl;dr version: For an emulsified sausage, use pork fat (preferably salted pork fat that has been subsequently rinsed or simmered), no matter what type of main meat you are using, and aim for a fat content of 35%.
With a standard chunky ground sausage, keeping your grinder, meat, and fat cold is important from a macro-scale physical perspective: let the stuff get too warm and your fat and meat will smear rather than chopping nicely. With an emulsified sausage, there's another factor at play: the stability of an emulsion is dependent upon the temperature at which it's formed.
First, let's define emulsion. An emulsion is a homogenous, stable mixture of two things that don't generally mix well. In culinary terms, we're talking fat and water. Mayonnaise, hollandaise, a vinaigrette, and a hot dog are all examples of a fat-in-water emulsion.
Ever notice how when two raindrops meet as they roll down a window, they'll jump together as soon as they touch? That's because water droplets are naturally attracted to each other, just as fat is naturally repulsed from it. The goal with an emulsion is to break up those fat droplets so finely that they get completely surrounded by water molecules, preventing them from coalescing.
There are two keys to accomplishing this. First, make sure that everything stays ice cold. Warm fat liquefies, and liquefied fat will break out of emulsion and coalesce. Second, add your fat slowly so that it is easier to break up and disperse it into small pieces.
To accomplish this, we start by mixing the lean, salted meat with the basic seasonings—in the case of weisswurst, that's lemon peel, parsley, mace (I used nutmeg, which comes from the same plant, has a very similar flavor, and is more readily available), ginger, and white pepper—and puréeing it in a food processor.
Next, purée some crushed ice into the mix (I crush the ice in a plastic zipper-lock bag under a pan). The ice not only keeps things cold, but it also adjust the fat-to-lean-to-water ratio in the mixture.
With pork meat, you generally end up adding around 20 to 25% of the weight of the lean pork in water or ice. I tried this with the turkey and found that the sausages were too wet and soft, exuding excess water like a sponge:
I took it all the way down to 5% before I was happy with the texture.
With the ice incorporated, it's time to add the fat (and onions, in this case). I chill my fat in the freezer until it's almost completely frozen solid, and then slowly add it to the machine with the motor running.
If all goes well, you'll end up with a creamy, homogenous mixture.
Bear in mind that the mechanical action of a food processor will heat up your mixture as it goes, which means that even with added ice and completely frozen fat, there's still a real risk of overheating. The goal is to keep the mixture from going above 50°F. Stop often, and check with a thermometer.
If you see it overheating, stop and place the mixture in the freezer (just chuck the whole food processor bowl in there) and let it chill until you can safely mix again. This 57°F mixture got too hot and subsequently suffered in texture. It wasn't inedible, but it was noticeably dryer than a properly-made mixture.
The salt level in a standard sausage is pretty strictly defined by how much you need to perform its magical meat-binding properties, but other flavorings can be adjusted at will. Like more parsley and less lemon zest? No problem. Do you really hate nutmeg and mace? Leave 'em out.
A good way to check the seasoning level of raw sausage is either to pan-fry a bit of it, or to throw a dime-sized dollop on a microwave-safe plate and heat it for about 15 seconds so you can taste and adjust.
Stuffing Your Sausage
There's no two ways about it: making sausage is, by its very nature, a rather... suggestive affair. If you are the kind of person who giggles like a school girl when you see something like this, well, you're going to love making sausage.
You can get all fancy with dedicated piston-style sausage stuffers or use the stuffing attachment on your meat grinder attachment, but for a relatively small quantity of emulsified sausage I find it easier to use a pastry bag with a round tip, which heats up the mixture less, and lets you fill the sausage at a controlled pace.
Here's your first test for the giggle-o-meter:
Calmed down yet?
For a weisswurst, hog casings are the casing of choice (you can order them online). They come packed in salt and will need to be soaked in a bowl of water for at least half an hour to soften them up and rehydrate them. Afterwards, I run water through their entire length by holding one end over the tip of a funnel and pouring water out of the tap down it, stretching and detangling the casing until the water runs clear out the other side. This will ensure that there are no major leaks or tangles down the line.
Once your casings are cleaned, pack your sausage mixture into your pastry bag (I like to fold over the top edge of the pastry bag about half way to make sure that the exterior of the bag stays clean), then feed a length of casing over the end of your pastry bag tip until you have only the last inch or two overhanging. About 10 feet is a good length to start with. Tie a knot in it, making sure to squeeze out any excess air.
Start filling your sausage by twisting the end of the pastry bag and squeezing firmly from the back. The sausage should come out of the tip.
Make sure you hang onto the casing as you go so that it doesn't go flying off and your sausages stay nice and plump. Sometimes it helps to get a partner during this phase. (teehee.)
A few things might go wrong while you're stuffing.
You want your sausage to be plump, but not so plump that it bursts when you try to twist it into link. Hog casings are stretchy, but they do have their limits. If you do find you accidentally break the skin, don't worry! Cut off the casing, squeeze the sausage mixture out of the broken part, tie it off, and add the squeezed-out stuffing back to whatever's left in the pastry bag (or just fry it in a skillet and eat it).
If you accidentally trap air bubbles in the mixture, don't sweat! Poke them out with a safety pin or needle. Go ahead—break right through that casing. A well-emulsified sausage (which yours undoubtedly is) does not need its casing to retain moisture.
And remember: the colder you keep things, the better your sausage will be. That extends right down to the stuffing stage. If it's taking you a long time to stuff, take a break, throw everything in the fridge, and start up again later. Your sausages will be all the better for it.
Has anyone ever come up to you and said, my, that's a well-emulsified sausage you've got?
No? That may change now.
Now that you've spent so much time and effort into making those perfect sausages, what's the best way to cook them?
Despite the fact that sausages retain moisture better than pretty much any whole-muscle meat on the planet, they can still be overcooked into dry oblivion.
Traditionally, weisswurst are served cooked in salted water or broth that's kept below a simmer the entire time to prevent the sausages from overcooking and becoming tough or dry. I bring a medium-sized pot of salted water to a bare simmer, shut off the heat, then add the sausage. I find that with 2 quarts of water, it will stay hot long enough to cook a half dozen sausages through.
If you've got the gear, the best way to cook a sausage is using a sous-vide cooker set at 145 to 150°F for about 45 minutes. You'll be rewarded with ridiculously plump and juicy results.
What's that? You're not into the austere German style of poached sausage, even when there's sweet mustard involved? No worries, there's absolutely nothing but cultural pressure and years of convention stopping you from frying up your sausage to give them a bit of color and snap. Either way, you'll want to start them off by poaching them to cook them all the way through.
Afterwards, I like to send them for a 10 minute rest in the fridge in order to chill their exterior just a bit so that they won't overcook or burst during the subsequent browning phase in hot, foaming butter.
As a dish on its own, weisswurst makes for a fantastic meal. As part of an epic turkey-three-way Thanksgiving, it can more than hold its own at the table. Unlike my kid sister. She tends to get a bit sloppy at family holidays.
About the author: J. Kenji Lopez-Alt is the Chief Creative Officer of Serious Eats where he likes to explore the science of home cooking in his weekly column The Food Lab. You can follow him at @thefoodlab on Twitter, or at The Food Lab on Facebook.