How to Pull Off Thin Hand-Pulled Lamian Noodles (part 2).
By TIM CHIN.Trial 4: The Wide World of Dough Reducers
Adding an alkali wasn’t the answer. I had to dig deeper. Based on one translated source, the composition of penghui includes sodium, potassium, and sulfur. And given my previous tests with potassium carbonate and sodium bicarbonate (both alkalis), I was willing to rule out the first two ingredients.
But sulfur? A quick search for sulfur additives in dough led me to this comprehensive post describing the role of dough reducers in industrial breadmaking. Dough reducers (or reducing agents) are a class of dough conditioners used to decrease mixing time and to improve extensibility. Chief among them are the protein-based reagents cysteine and glutathione; and, coincidentally, sulfites.
I reached out to the author, Dr. Jacinthe Côté, a food biotechnologist and Product Management Director at Lallemand Inc., a major research, development, and manufacturing company that specializes in yeasts and bacteria for natural fermentation processes, including industrial dough processing. According to her, reducing agents act like mixing to reversibly break down the gluten network, resulting in increased extensibility. “You have to be aware that those [disulfide] links can be broken. If you manipulate the dough, or if you stretch it too much, the bridge can be broken. It can be done mechanically, or it can be done chemically.”
For Dr. Côté, gluten development during mixing is best thought of as an oxidation-reduction reaction, hence the name “dough reducers.” “The formation of a disulfide bridge is an oxidation reaction…involving gluten [proteins] containing sulfhydryl (or thiol, denoted by -SH) groups. The oxidation process links the sulfhydryl groups on one protein with another.” Breaking those disulfide bonds chemically is a reduction process known as disulfide interchange. Do you need to know all that hard science? Not really. What’s important is this: Each reducing agent participates in some form of disulfide interchange to relax a dough. But they aren’t all created equal.
Sulfites.
Sulfites are a common reducing agent used in cookie, cracker, and biscuit production; they are used to relax doughs for shaping. These reagents act like caps, covering the reactive sulfhydryl groups on gluten proteins. This capping makes it difficult to reform disulfide bonds—resulting in a dough that can’t form a strong gluten network in exchange for extensibility.
The most commonly available form is a salt, such as sodium metabisulfite (which you can find at most homebrew stores as a preservative for wine making). Unfortunately, sulfite salts have the distinct odor of rotten eggs, can cause sensitivity reactions in some people (rashes, hives, indigestion, as some sulfite-sensitive wine drinkers may know), and are closely regulated by the FDA. They are effective at levels between 20-100 parts per million, so even if you used 1/16th of a teaspoon of a sulfite salt, you would need to add it to several pounds of dough to be effective. Ultimately, sulfite salts are not suited for home cooking (unless you’re making a huge batch of dough).
I had read that penghui smelled strongly of rotten eggs. Based on its reported composition and smell, I suspect that penghui contains some kind of sulfite salt, which would explain its dough-relaxing properties. In the end, I didn’t think sulfites were a viable—or healthy—option for the home cook.
Cysteine.
Cysteine is an amino acid, and the go-to reducing agent in commercial bread production. It’s cheap to produce, you can add it directly to a dough, and it acts quickly, reducing the number of disulfide cross-links between glutenin chains via disulfide interchange. Like sulfite salts, cysteine must be used in small amounts (10-90 parts per million), so it’s not the most practical choice for home cooks looking to make a single loaf of bread or a small batch of noodles. While you probably won’t find it in the baking aisle at your local grocery store, you can buy cysteine over the counter as a dietary supplement. But it does have a bad rap among health-conscious consumers: Most cysteine is extracted from the feathers of birds and hog hair. “There’s a big chemical extraction process,” explains Dr. Côté, and it results in a product that hardly resembles feathers or hair at all.
Despite the bad reputation, I decided to give cysteine a shot. I split open a pill of L-cysteine and sprinkled 0.1 grams of the powder into a working recipe of bread flour, salt, and water. The smell of metallic, faintly rotten eggs immediately stung my nostrils. Within minutes of kneading, the dough turned to a puddle in my hands. I could stretch the dough seemingly infinitely. But the dough lacked any semblance of structure, making it impossible to pull noodles that could hold their shape. I had added too much cysteine. Clearly, using cysteine could work to relax my dough, but it was also impractical and difficult to use correctly: I couldn’t justify asking home cooks to buy a whole bottle of cysteine just to use a couple milligrams of the stuff.
Glutathione (a.k.a. The Winner).
Glutathione is a peptide (a peptide is smaller than a protein, usually containing less than 50 amino acids) that contains cysteine, and functions in a similar way to relax doughs. Most commercial glutathione comes from natural sources like heat-treated, inactive yeast. “When you’re drying the yeast, you’re stressing [it] a little bit, and some of the cells die,” says Dr. Côté. “When the yeast cells die, they release some of their components that are inside the cell. One of the components that is naturally occurring is glutathione.” Lallemand specializes in a product called Fermaid, a non-leavening yeast product that is abundant in glutathione. Still, I didn’t want to buy a specialty, industrial-grade ingredient just to make some noodles (like sodium metabisulfite, you can sometimes find Fermaid at homebrew stores).
But what about nutritional yeast? Technically, it’s deactivated yeast, too, so it would have some proportion of glutathione. Could it work to relax a noodle dough? I pitched the idea to Dr. Côté. She lit up. “Ok! That’s a good one, too. That logic makes sense. A lot of bakeries just use regular inactive yeast (which is generally available industrially). I think there’s about 1.5%–2% glutathione in that product, and it works.” You can make inactive yeast by slowly cooking or drying out fresh yeast, but the process is time consuming. And if nutritional yeast was readily available and just as good, it seemed like a better option.
I started testing with a tablespoon of nutritional yeast mixed into my dough. Unlike my tests with cysteine, I found I could use reasonable amounts of nooch without worrying about over-relaxing the dough. To speed mixing up, I combined all the ingredients in a food processor and ran it just until a dough formed, then transferred the dough to the counter. After a few minutes of kneading and twisting, the dough relaxed considerably and became more extensible.
But unlike the dough with cysteine, it still retained its structure. As I dialed up the amount of nutritional yeast, the dough became even more extensible. By the fifth trial, I was able to pull noodles. The cooked noodles were ideal: chewy, even in thickness, and slurp-worthy. Using nutritional yeast also had a couple unintended benefits: It tinted the noodles a pale yellow—reminiscent of Japanese alkali ramen noodles—and it imparted subtle umami flavor (nutritional yeast is rich in glutamate, giving it a savory, cheesy quality, which explains why it’s often used as a stand-in for Parmesan in vegan recipes). And the best part? I went from mixing to pulling and cooking noodles in 15 minutes flat.
Finally, I had found a reliable way to pull noodles—or at least a way to get a dough with repeatable extensibility. And I didn’t need special equipment, special ingredients, or years of noodle school training.
Refining the Formula.
I solved the hardest part of the noodle problem: I had extensible, cooperative dough that could be both pulled repeatedly and made very quickly. All that remained was to home in on a foolproof formula for optimal handling and texture. I’ll break the rest of my testing down briefly, ingredient by ingredient:
Flour.
Flour is by far the most important ingredient in any dough. I tested various brands of low-protein cake flour, all-purpose flour, and bread flour. Each of these flour types vary in their gluten potential (gluten potential is a term for how much gluten development is possible). Cake flour sits at 7-9% protein content (protein content includes proteins like albumin and globulin, in addition to gluten proteins); at the other end of the spectrum, bread flour contains 12-14% protein, depending on the brand. A flour with higher protein content tends to form a dough with more gluten potential and, consequently, more elasticity and chew.
In the end, I found that bread flour (I used King Arthur bread flour, which has the highest protein content available of all common flours you can find at grocery stores) resulted in noodles that pulled easily but had the proper elasticity for structure. The noodles held their shape well during pulling, and separated into even strands. The cooked noodles were chewier and had a more pleasant spring compared to noodles made with other flours. As the protein content of the flour decreased, dough handling and chew worsened. For instance, the same formula with cake flour was stickier and tended to droop and stick to my hands while pulling and stretching; the resulting noodles were uneven, lacked chew, and were spongy. I also observed that higher-protein flours were able to absorb more water without becoming sticky and unmanageable.
Water.
In general, water serves two primary functions in a noodle dough: It is essential to hydrating flour to form a stable gluten network; and it facilitates extensibility, making a dough stretchable. It’s useful to think of dough as a suspension of solid particles (starches) in a viscous fluid. If you add more water to that dough, you are increasing the size of the suspension, giving more space for the solid particles to move around, which means the dough will stretch more. At the same time, adding more water makes a dough stickier, harder to handle, and less elastic. I found the ideal hydration for my noodle dough (as a percentage of flour weight) sat between 62 and 68 percent. At levels lower than this range, the dough tended to be too elastic and too resistant to stretching. At a hydration higher than 68 percent, the dough was more extensible, but stuck to the work surface and to my hands, and was difficult—if not impossible—to stretch evenly.
Salt.
Salt is used mostly for flavor in my formula. But depending on the concentration, salt also acts as a conditioner in a dough, strengthening the gluten network. I tested doughs with and without salt. I found that without salt, doughs tended to be more slack and sticky. Adding salt made doughs more elastic, but easier to handle.
Oil.
Oil has several effects on dough handling and cooked noodle texture. In general, adding oil inhibits gluten development, since a portion of flour absorbs that oil during mixing. Oil also affects viscosity in a similar fashion to water: It makes a dough softer and more extensible. Lastly, oil seems to improve dough handling by mitigating stickiness to surfaces and hands. That final quality was integral to clean, even stretching in my recipe. Adding oil to my dough slightly increased extensibility without having to add even more water, which would have made my dough too sticky to handle.
Nutritional Yeast.
For optimal extensibility, I found nutritional yeast to be effective between 5 and 8 percent of the total flour weight in my tests. As the protein content of flour increased (up to King Arthur bread flour), I could dial up the amount of nutritional yeast to the top end of that range without compromising structure. As the protein content decreased (to say, Pillsbury cake flour), less yeast was required, and additional yeast made the dough too sticky and slack*.
*If you’re curious, nutritional yeast contains 2.5 milligrams of glutathione per gram.
A Note on Alkali.
What about all that hype around penghui and kansui? For this recipe, I noticed that alkali did make my noodles chewier; but it also made pulling noodles more difficult, and the cooked noodle shape was wavy, curled, and uneven. My noodles had plenty of chew already from high-gluten bread flour, and the added benefit in texture wasn’t worth the regression in dough handling and shaping. In the interest of keeping things simple, I decided to leave alkali out. You could definitely experiment with adding some alkali to your noodle dough to improve chew, but keep in mind that it will negatively impact extensibility.
Rules for the Road.
So now we’ve got a dough formula that works. But it’s still up to you to bring it all home and pull noodles. Here are some guidelines and words of advice to keep in mind for successful noodle pulling.
Use a Scale.
You need a scale. I’m not going to pretend otherwise. You might think you could get away with your heirloom tablespoons and that cute chipped porcelain measuring cup that you copped from Goodwill, but trust me when I say: It will do you no good. If you want consistency, use a scale (preferably digital ).
Stretch and Twirl.
After the formula, the most important aspect of this recipe is proper kneading before pulling noodles. All that stretching, twirling, and doubling over of dough might look flashy, but the process serves a function: It aligns gluten in a roughly linear orientation. Most of the time, general kneading (especially in a mixer) mashes gluten proteins in a random, non-linear way. That randomness is great for breads, which must expand in all directions when rising or baking. But noodles are straight, and need to extend in a linear way. Stretching and twirling is basically linear kneading: You’re mechanically making and breaking bonds in gluten, and aligning them in roughly one direction.
Practice Pulling.
Once you’ve sufficiently developed and aligned your dough, it’s time to pull noodles. This stage is a perfect time to practice. Ultimately, pulling noodles is a hand skill that takes some repetition and feeling. “My recommendation is don’t jump the gun and try to boil your noodles. Just practice,” Luke recommends. Generally, flouring the table and rolling the dough in flour helps keep the noodle strands separate when pulling. But once you’ve floured the table, you have to pull noodles and cook them, since additional flour would be worked into the dough, throwing off our intentionally crafted formula.
Fortunately, the un-floured dough has that repeatable extensibility, so you can practice the pulling motions repeatedly, without fear of the dough tearing or snapping back. “Just keep trying to make noodles, over and over again—without actually flouring them and throwing them into a pot and expecting to eat anything. A lot of this is really the dexterity and knowing how to hold the two ends of the dough.”
Don’t Be Afraid.
If I’ve done my job, this should be a very forgiving dough. So don’t be discouraged if you can’t get the pulling motions quite right initially. If the dough tears (it shouldn’t), just roll it back up and try again. Don’t stress. If the noodles are uneven, try again. If one or two strands break as you’re pulling, don’t freak out. Remember: It’s just dough.
Go Forth and Pull.
At this point, the noodle masters of yore are likely rolling in their graves. Traditionalists out there will probably put me on full blast. “Lamian doesn’t have nooch! How dare you. That’s not authentic.”
Tradition was never the point. Exploration and understanding—they are worth far more. I could have just as easily told you to go out and smuggle in some penghui, knead your dough for hours, and make some authentic noodles. But this is a lamian recipe for home cooks. My goal was to develop a noodle dough that anyone could pull; a way to practice noodle pulling without resorting to prohibitive means or herculean efforts.
Just to make sure, I sent my recipe to Luke for him to try out. He emailed me back a couple days later with pictures and even a video of him pulling noodles. It took him ten minutes from mixing to eating—a personal record. “I’m kinda speechless...huge stamp of approval from me!”
No matter the method, making lamian is magic. It’s a perfect demonstration of the alchemy, and chemistry, of cooking. It embodies the excitement, the thrill, and the spirit of making something amazing out of the ordinary. Learning about the process has been equally enriching. So go out and make some lamian dough. Practice, pull, and practice again. Then you'll be ready to cook them up and slide them into a fragrant bowl of lamb soup. (Stay tuned for that recipe.)
(source : https://www.seriouseats.com/recipes/2020/04/hand-pulled-lamian-noodles)
