Knackwurst – A Lightly Fermented Sausage
As my journey to Europe is focused on discovering how microorganisms are used to preserve local foods, I have been really excited to be making knackwurst every Tuesday for the past three months. Although the butcher has been practicing for only five years, the knackwurst that he produces is well-known in the area and is requested throughout Germany. And I will confirm that it is delicious.
As in most beloved foods, there is not a single agreed-upon recipe. Some include marjoram in the mix; many recipes call for varied proportions of spices. But every single person I have talked to agreed on one thing: the meat must be quality and fresh. Frozen cuts and ugly pieces are saved for the cooked meats (blood sausage and Sülze). And liverwurst is almost entirely made of ugly pieces of meat. Good knackwurst demands only the best.
Knackwurst Recipe (per one kilogram of pork):
- 20g Sodium Nitrite (Pökelsalz)
- 7g Pepper (Pfeffer)
- 1/2 tsp Nutmeg (Muscat)
- 1 tsp Garlic (Knoblauch)
Use the 5mm holes in your meat grinder (tr., Fleischwolf). The ground meat is mixed, sometimes with a bit of water for binding, until the proteins bind and show cohesion. For a traditional ring, you can use some middle-intestine from a cow and loop as shown below. For a bit of snacking, use sheep or goat casing and form into sticks. This is then cold smoked for flavor, or left to air dry. Note the meat is not cooked at any point.
Observations
The other sausages made in this butchery do not use pickling salt (tr., Pökelsalz), as they are generally intended to be eaten fresh (bratwurst and gehacktes) or will be canned (Sülze and blood sausage). Using normal salt (without iodine) will initially maintain the red color of the meat, but as it ages, that red color will turn to grey. Oddly, the sodium nitrite (i.e., the pickling salt) will initially turn the meat grey, only to have the red color return and remain over time.
Why sodium nitrite, and what does it do? An excerpt from my Microbiology textbook (Tortora, et al., 11 ed., 2013):
Sodium nitrate and sodium nitrite are added to many meat products, such as ham, bacon, hot dogs, and sausage. The active ingredient is sodium nitrite, which certain bacteria in the meats can also produce from sodium nitrate. These bacteria use nitrate as a substitute for oxygen under anaerobic conditions. The nitrite has two main functions: to preserve the pleasing red color of the meat by reacting with blood components in the meat, and to prevent the germination and growth of any botulism endospores that might be present.
What is truly fascinating is that the recipe above does not inoculate the meat with any specific bacteria. While these bacteria are understandably already in the meat, the correct mixture of bacteria that make this butcher’s knackwurst well-known is living in his workshop. And though the equipment is cleaned after every use and wiped down with antibacterial solution, these hardworking bacteria stick around to inoculate the next delicious batch of knackwurst.
Fresh knackwurst (a bit grey), and smoked knackwurst (regained the red color):
Knackwurst can be eaten immediately; in fact, most of the supply made on Tuesdays is gone by the weekend. I have heard that some people like to boil fresh knackwurst and then suck the contents from the casing (I was warned that the hot fat can burn your mouth).
I have also been recommended that I let the knackwurst age many months before consuming. As the sausage ages, the water continues to be driven off and the sausage shrivels in its casing (hopefully not too drastically; otherwise, the butcher had sold you expensive water). The knackwurst then resembles a good salami in its toughness.
However, I prefer my knackwurst aged two to four weeks. At this point, it is still a bit moist, I can cut it easily, and it is not chewy. No matter your preferences, this sausage is delicious and will be a regular at my breakfast table.
