Editor’s note: This recipe is adapted from a recipe by Chef Helen Nguyen of New York’s Saigon Social, who consulted with the author for this article.
Whether served rolled into small logs, cut into squares, or bundled in tropical leaves, nem chua—a beloved type of Vietnamese cured pork—manages to deliver on almost every flavor we crave: sourness from lactic acid; a subtle sweetness imparted by banana leaves or sugar; a pungent bite from raw garlic; ample saltiness; floral spiciness from black pepper and funkiness from white pepper; and a good dose of raw-chile heat. “Usually people use plastic or banana leaves, but my grandpa would wrap them in guava leaves,” says Chef Helen Nguyen of Saigon Social, a homestyle Vietnam restaurant in NYC. “It takes on a slightly herbal bitterness and almost smoky taste.”
The geographic footprint of nem chua isn’t limited to Vietnam—it edges into Cambodia, Thailand, and Laos, too. In the latter two countries, the name of the finished product is typically written as naem (or sometimes nam) and the preparation also incorporates cooked sticky rice in the mixture. In each area, differences in heat levels, days of fermentation, and methods of forming the preparation make for a nuanced range of possibilities in the final nem chua. However, across all regions, nem chua can be enjoyed both as-is (it’s a “perfect accompaniment to an ice cold beer,” says Nguyen), as well as an ingredient in cooked dishes, like naem khao (a crispy rice salad made by frying and crumbling rice balls then mixing them with naem) and phat naem sai khai (naem stir-fried with egg).
Although Nguyen considers nem chua a “top 10 dish of Vietnam,” she says that “more education is needed about it [in the US], because people are worried about raw meat.” Hence, she compares nem chua to charcuterie for those unfamiliar with it: “It’s just cured meat, like a cured sausage, or a dry salami.” While the traditional procedure of making nem chua is to let the ground meat mixture ferment naturally outdoors for a few days, the “modernized” process involves a store-bought curing packet that shrinks the timeline to just 24 hours and dramatically reduces variability across batches.
One of the most popular brands, Lobo (which Nguyen also recommends), markets the curing mix specifically as “nam powder.” The information on many packets is typically written only in Thai script, but Hong and Kim from The Ravenous Couple, a Vietnamese cooking blog, sent me one where all the contents were labeled in English. With an ingredient list in hand, I set out to confirm exactly what kind of transformation the raw meat mixture was undergoing.
First, Anna Bauer, a food scientist who works for a major national packaged foods company, pointed out that nem chua made with this packet is a cured, but not fermented, product. “The meat is only in the fridge for 24 hours, and since the packet doesn’t list any microbes in the ingredients, it doesn’t have time to be ‘fermented’.” However, it still takes on a distinct tanginess due to the main ingredient, glucono delta-lactone (GDL), which breaks down “into gluconic acid due to the high level of moisture in raw meat and lowers the pH, hindering the ability for harmful bacteria to grow.” Additionally, Bauer says that because GDL “denatures some of the proteins, it changes the texture of the nem chua.”
The next two main ingredients, glucose and dextrose, are two names for the same molecule and add sweetness to the final product. While this recipe’s quick method of nem chua doesn’t leave time for bacterial fermentation, during longer curing methods these types of sweeteners “provide an easy fermentation substrate for microorganisms to munch on,” says Bauer. “Lactic acid bacteria love glucose and will produce lactic acid as it metabolizes the glucose. This further decreases the pH of the sausage and leads to complex flavor development.”
The nicely bouncy, supple bite of nem chua is also partially due to sodium tripolyphosphate (STPP), an alkaline salt that “helps modify muscle fibers to…bind them during the curing process,” explains Claire Thrift, a food scientist who has worked on packaged foods for a range of major businesses, such as Post. “STPP has also been shown to increase migration of salt and nitrites into muscle fiber, ensuring even distribution and thus a safe and effective cure.” According to Bauer, the phosphates are also specifically binding to the water in the meat, which “helps the emulsification by not allowing syneresis [the oozing out of liquid].” The result contains more moisture and is easier to chew, Bauer says—similar to “a Slim Jim versus a jerky.”
For those concerned about nitrite, which is also listed in the ingredients (in sodium nitrite form), Thrift says that the sodium erythorbate present helps “inhibit nitrosamine formation, which are the carcinogenic compounds that form when nitrites and proteins interact in your gut, and are responsible for the bad reputation of cured and processed meats.”
Why use nitrites at all? Because they are necessary to prevent the growth of clostridium botulinum, the bacteria that causes botulism, and offers the “cured” flavor we are now accustomed to. It also changes the final color of the product to a more appealing red.
While the process of making nem chua with the packet seasoning is very controlled, all the food scientists I interviewed encouraged those who make the dish to be mindful of food safety, cleanliness, and the use of quality meats. Professor Eric Decker, head of the Department of Food Science at the University of Massachusetts, Amherst, says there is potential for trichinosis* when using pork for nem chua, given that the meat is not fully cooked, but this is preventable if the “pork is chemically tested for trichinosis, or frozen at certain temperature and time regimes to kill the trichinosis.” Alternatively, beef may be a better option, although that still constitutes “a microbial risk, just like [eating] beef tartare.”
Nguyen, who has trained under Pat LaFrieda and is a meat expert herself, recommends striking up a relationship with your local butcher to source the best meat possible, and using the leanest cut of pork (or, optionally, beef) available when making nem chua (she explains fattier cuts tend to go rancid more quickly). For pork, a tenderloin or loin is a great choice; for beef, beef eye round. Even with those naturally lean cuts, Nguyen will still trim off as much excess fat as possible. She recommends using a meat grinder at home—a “double grind is the best”—but tossing everything into a food processor also yields suitably delicious results.
If you live near a grocery store stocked with Southeast Asian products, make sure to also grab a few bags of cooked, sliced pork skin (typically kept in the frozen section). These thin, translucent strands create the distinct chew in Nguyen’s nem chua, and are generally found in nem chua preparations across Vietnam (including mass-produced varieties). Bite into a piece and you’ll see those little flecks peeking out against the pink flush of freshly ground pork loin, surrounded by specks of garlic, chile, and peppercorn. “It’s not the same without the skin,” Nguyen says, “it’s like eating a cheeseburger without cheese.”
To Nguyen, nem chua is not only a staple of her upbringing—she likens opening the refrigerator and seeing nem to “finding a ham and cheese or bologna”—but also a fond memory of her father, who passed away 10 years ago. “It was one of his absolute favorites,” she recounts. “He would have a beer with dinner and we would eat nem. It’s a snack, it’s bar food, it’s street food, it’s everything!”
*Per the CDC: Trichinosis, or trichinellosis, is a type of roundworm infection that results from eating raw or undercooked meat infected with the trichinella parasite, particularly wild game meat or pork. Cases of trichinosis in the U.S. have declined sharply over time (see historical graphs), and now the risk of trichinosis from eating commercially raised and properly prepared pork is very low.