Apr

21

2022

The Art and Science of Cooking With Blood

By Mark Hay

While attending the 2016 Oxford Symposium on Food and Cookery,1 the culinary historian Laura Shapiro decided to sit in on an unusual presentation—on the art and logic of cooking with blood. 

The presenter, one of a handful of cooks pushing people to reevaluate any knee-jerk disgust they may feel at the prospect of eating blood, pointed out that cultures across the globe have long and rich traditions of cooking with it. It’s really only faded off of menus in America2 and a few other societies over the past century or so. She argued that modern qualms about working with blood are phenomenally wasteful. It’s a rich source of protein and vitamins, and accounts for up to 11 percent of the weight of a slaughtered animal. And she concluded, Shapiro recalls, with a call to make “blood easily available in cartons, like yogurt,” for any who want to experiment with it. 

At the end of her presentation, the impassioned chef handed out chocolate-and-blood cookies she had baked before the event. Game to give them a shot after this spiel, Shapiro took a bite—only to instantly balk in disgust. The cookies had “a strong, awful aftertaste,” she says. Like iron. 

In theory, Shapiro got what the presenter was driving at. But in practice, she “wasn’t persuaded.”

Shapiro’s take on efforts to revive blood cooking in the West is hardly unique. Food writers like Maxine Builder, at least mildly intrigued by the waste-not snout-to-tail logic, heritage appeal, or sheer novelty of the idea, have tried blood recipes, then spit out the finished dishes, disgusted by their strong earthy-metallic flavor, or their unique slimy or gritty textures. Elisabeth Paul, a former food researcher (and current hog breeder, butcher, and salumi maker in northern Italy) who helped develop a few prominent new blood recipes, has said she struggled with the taste of blood and spent a good chunk of her experimental time and efforts figuring out how to mask its harshest notes. Even Chef Jamie Bissonnette, a proponent of cooking with blood, has admitted that he doesn’t think it tastes good on its own, and that it requires great skill and ingenuity to turn blood into something that most modern American restaurant-goers will enjoy.  

Fortunately, over millennia of trial-and-error humans have developed a solid base of skills and ideas for how to use blood not just grudgingly as an efficient nutrient source, but enthusiastically as a cornerstone of reliably delicious foods. However, thanks to our recent history of culturally ingrained aversion to blood, especially in the kitchen, Western cooks, both at-home amateurs and seasoned pros, don’t have many resources to turn to in order to learn how to work with blood. 

To remedy this knowledge gap, The Blood Project recently reached out to over a dozen chefs, culinary historians, and food researchers familiar with the art of blood cooking. We also read up on every resource on blood cooking we could find. Here’s what we learned in the process about the easily avoided pitfalls, and vast potential, of working with blood. 


As Vietnamese food historian Trinh Khanh Linh has noted, there is no one universal approach to cooking with blood, in part because there is no universal standard for what makes food delicious. Although a few flavors like fat, sugar, and salt are broadly beloved (likely because they signal basic macronutrients that we all need to live), cultural tastes vary wildly according to what people are exposed to while growing up, as well as the messaging they internalize about good vs. bad foods.  

Blood’s minerality especially fails to line up with the flavors American culture prioritizes, which Amy Bentley, a scholar of the cultural history of foods, characterizes as “bland, salty, fatty, or sugary” bases “altered by spicing,” as opposed to inherently pungent flavors. Its mushy-slimy texture also doesn’t align with the country’s preference for “crisp, firm, or creamy” items. 

Modern Western culture also tends to paint blood as a food of last resort—something Mongol warriors on long campaigns, European trappers and colonizers in the wilderness, or Irish herders enduring famines drank straight from the veins of their livestock just to sustain them. Something cultures worked into sausages and stews because they needed to draw as much out of slaughtered animals as possible. Something societies abandon as soon as they grow prosperous enough to indulge in the choice to eschew nutritious but grim foods for solely delicious dishes. Pop culture also paints it as a sign of supremely alien and savage cultures. See: Star Trek’s Klingons, who are fond of blood wine and pies, alongside live worms—which most humans can’t stomach. 

Jennifer McLagan, a chef, originally from Australia but now based in France, who recently wrote a cookbook devoted to modern blood recipes—and who is arguably the leading voice of the modern Western blood cooking revival—acknowledges that many cultures have used blood as “emergency food” in “extreme conditions.” (She adds that a well-nourished horse can spare about a liter every 10 days “without damaging its health,” while a cow can spare four every two weeks. “In fact, a cow bled regularly over two and a half years will provide about the same amount of protein as if you waited the same period of time and slaughtered it,” she argues. So bleeding is a great way to draw out a resource.)  

Emiko Davies, an Australian-Japanese cookbook author, now based in Tuscany, who’s long been fascinated by southern Italian blood sweets like sagnuinaccio dolce, a simple pudding made by combining fresh pig’s blood, milk, sugar, and chocolate, with nuts or dried fruits added in on occasion for flavor, adds that most blood recipes do indeed stem from “another time, when food was more scare and … if you had a pig, come the winter season, when it was time to butcher it, every single part of it was to be used.” 

Davies adds that a few blood recipes are also purely ritualistic or medicinal—like snake blood wine, a brew found in parts of China, Taiwan, Vietnam, and elsewhere, which is made by killing a serpent in front of diners to demonstrate its freshness, squeezing the blood into a small bowl, then mixing it with liquor. (Davies, who lived in China on and off for 8 years, has witnessed this process.) Some forms of Chinese traditional cooking prescribe this not as a delicious dish, but as an invigorating cure-all. Similar supposedly restorative blood tonic recipes abound in Bolivia and Nepal. They were common in Europe and North America as well, until about a century ago. In fact, in the mid-19th century Americans of all classes lined up at urban slaughterhouses to drink beef blood straight from a chalice, not because they were short on food and desperate for protein but because they believed in its restorative powers. What’s more, until at least 1908 some people in central Europe reportedly drank the blood of executed men straight off the scaffold as a sort of elixir. (Belief in the healing properties of blood drinking persists in a surprising number of Western circles to this day.)

But many communities embrace blood still today, in the absence of widespread nutritional deprivation, precisely for its strong, unique flavor, its thick, gelatinous texture, even its deep, red color, which turns chocolaty brown when subjected to heat. Davies believes that the “metallic taste is intriguing—not off-putting at all, but wonderful.” Juergen Knorr, a chef and culinary instructor who grew up eating blood-based food in central Europe, believes it “adds richness and depth to a recipe’s flavor profile.” 

In many parts of Europe, it’s a beloved staple in sausage and beef or game stews, as its strong flavors deepen those of other ingredients. In Scandinavia, blood pancakes with a dollop of lingonberry jam are widely enjoyed as hearty winter fare. In parts of Italy, blood is often associated with Carnivale treats—like migliaccio, a mix of pig’s blood and flour used to make a thick crepe, often flavored with citrus and sprinkled with sugar and cinnamon. Its savory elements offer an alluring counterpoint to otherwise overwhelming sweetness. (“Iron and fat in the right balance create a contrast that is the essence of blood sausage,” too, argues Andrea Falaschi, the scion of a family that’s made mallegato, a northern Italian pig’s blood, pork fat, raisin, cinnamon, and pine nut sausage, boiled and then sliced and browned in olive oil in a pan, since 1925.) Over in Taiwan, pig’s blood and sticky rice cakes steamed, soaked in soy broth, and coated in peanut flour are a night market treat, prized for layered savory notes. And in northern Thailand, laab dib, a mixture of raw meat, fresh blood, and bile cut with spices, is prized for its bracing, intensely bitter bite and tang. 

Blood pancake with cow berry jam. Emmoth/Shutterstock.com
Pig’s blood cake is a street food delicacy served on a stick from market stalls in Taiwan. Pig’s blood cake is made with pork blood and sticky rice. Topimages/Shutterstock.com

Westerners used to eat more blood foods, eagerly and across social and geographic lines. But many mainstream Western societies slowly lost their taste for these dishes in part because of the industrialization of slaughter. This system involves unsanitary conditions that easily spoil blood, itself particularly prone to contamination. Blood also congeals rapidly unless it’s properly collected and preserved. So putting distance between consumers and slaughter has made it hard to get blood into kitchens, and thus to expose people to it. 

“Getting your hands on good, quality, uncoagulated blood is the hardest part of cooking with blood,” says Gwyn Uttmark, a blood cooking enthusiast who’s set up a guide to sourcing, handling, and working with it online. “Building a relationship with a local farmer or butcher” is the best way to access it for most. 

Class politics and posturing in the 19th and 20th centuries also led to the notion that blood and offal—cheap parts of animals—were somehow lesser than the more expensive cuts of an animal, a corrosive social pressure that led to their association with poverty.3 (Offal does share some of blood’s sweet, mineral flavor. So, a lack of exposure to organ meats in the many modern Western communities denies people an on-ramp to appreciating the texture and flavor of blood.)4

“We are not condemned to live and die in the taste world in which we were raised,” though, argues McLagan. “Our palates are malleable. They can change with exposure to new foods.” 

Notably, in the 19th century many of the women who went to drink blood at slaughterhouses in large American cities reportedly grimaced with every sip at first, but slowly developed a taste for it. One told a writer at the time that, after growing accustomed to it, blood reminded her of warm milk. 

But even within a culture that embraces blood, either for its own flavor and texture or for its role as an adjunct to other flavors and textures, appreciation may vary wildly not just according to personal preferences, but also by biology. A few studies suggest age and hormone levels affect people’s ability to detect key compounds in food, including metallic notes in blood. “Hormone fluctuations really impact how metallic it tastes to me,” says Uttmark. “Those who otherwise enjoy my cooking also usually pass when they’re on their periods.” (This is something other blood chefs have noticed, as well.)

So if you want to make blood taste good, you need to know who you’re cooking it for. What views do they hold about what makes something taste good in general? About the flavor profile of blood in particular? Do they have experience with any blood foods? With offal? Might their bodies—their hormonal profiles, genetic makeup, or even level of olfactory function—affect their taste? This variability may make any attempt to draw out best practices seem like a fool’s errand. But that won’t stop us from trying our best to provide a few actionable insights. 


In 2013, after members of the (now defunct) Nordic Food Lab tried a pig’s blood macaroon with a blue cheese center at Chef Andoni Aduriz’s legendarily inventive restaurant, Mugaritz, they decided to figure out what other new dishes they could work this long-neglected ingredient into. So, they tasked Paul and a few other researchers with investigating its composition, then playing around with how to manipulate it. Her team’s basic takeaway was: Blood is a liquid egg

Literally. Egg white and blood are both primarily composed of albumin protein in watery serum. The Nordic Food Lab suggests substituting 65 grams of pig’s blood for 58 grams of egg, or 43 grams for 33 grams of egg white, in any recipe. It will serve the same function in the recipe; it has all the same coagulating and emulsifying properties. You can use it to bind bits of sausage or baked goods. To thicken sauces, and give them a nice, glossy sheen. To make fluffy cakes, akin to tamagoyaki. These blood tofu cubes are a common additive to soup in East and Southeast Asia, prized for their mild flavor and custardy texture. You can even use it to make noodles. (“Blutknödel, they’re a thing in Germany,” says Chef Knorr).

Davies suspects that blood is a major component in so many traditional sweets and cakes due to the scarcity of eggs in the winter in the past, and the abundance of blood following cold season animal slaughters. But Paul notes that it also has a few one-ups on eggs: It does not trigger egg allergies or sensitivities, which are among the most common food intolerances. It also offers more protein and iron per calorie than egg—and it boasts heme iron, which is easier for our bodies to absorb than other forms of the mineral. It’s even a bit better at making flexible, stable peaks when whipped for a baked good. 

However, while blood is as versatile as eggs, it’s even more sensitive. Like eggs, it will curdle up when overcooked; you can’t heat blood albumin above 167 degrees Fahrenheit without messing with its texture, its structure. Overheating blood also makes its metallic flavor come out all the sharper, adds Knorr, thanks to a unique chemical reaction. And it coagulates when left out at room temperature for just a little while without any preservatives, unlike the hearty egg white. 

Knowing about blood’s basic protein composition, and its similarity to eggs, tells us a lot about what we can put it in—how to play with its structural-textual properties. But it doesn’t tell us much about how to manipulate blood’s flavor in a dish. Unfortunately, while scientists in the late 19th century studied the raw nutritional value of blood as part of an industrial zeal for drawing out the latent efficiency in natural products, “no one has ever quantified the flavor compounds in blood,” explains Michael Chao, a meat scientist who grew up in Taiwan, where he says he ate plenty of bloody soups and snacks. Nor can you find many collections of broad, anecdotal culinary wisdom about the properties of blood, even in regions that still actively use many blood recipes. “It’s not an interesting topic to many people, that’s probably why,” muses Knorr. 


“I don’t have any scientific basis for this,” Chao says, “but I believe there is a flavor and taste difference between different animals’ blood, because each would have different levels of protein and fat. There should also be differences in their specific protein and fatty acid profiles.” They may contain different levels or concentrations of iron, among other vitamins and minerals, as well. 

McLagan and Uttmark say they’ve never noticed a flavor difference between any of the animal bloods they’ve used or eaten. However, McLagan notes that old cookbooks do distinguish between bloods, “claiming that lamb’s is the sweetest, pig’s the richest, and hare’s the most delicate.” Culinary lore holds that pig’s blood is especially common in blood cooking both because swine are easy to obtain, and because of its light, sweet, yet rich nature. Cows are also accessible, but Knorr notes that their blood is especially gamey and metallic, making it harder to work with unless you’re looking to really dig into the intensity of that flavor. (Recipes across the world also call for chicken, duck, goose, and yak blood. But there’s far less information and kitchen wisdom about what sets those bloods apart available in English.) 

Farmhouse lore also maintains that the age and sex of an animal, its health, and its condition just before the killing blow can all have a major impact on the flavor of its blood. This makes sense, Knorr argues, because all of these factors will change the balance of key compounds (like hormones) in their blood. “The more relaxed an animal is, the better and sweeter the blood,” he argues. Uttmark adds that “the fresher the blood and the younger the animal, the less gamey.” 

Many Western chefs who tout the potential of blood frown on freezing it to extend its short, oh-so-perishable shelf life, because doing so breaks down the bonds between proteins, definitely leading to coagulation and allegedly robbing it of sweetness. Traditions that aren’t as interested in the sweet elements of blood, and are open to coagulation, may not have a problem with this; that may be why so many East Asian markets only sell pre-coagulated or frozen blood.  

But freezing isn’t the only means of preserving blood from both spoilage and coagulation. Some people use salt, others Vitamin C, vinegar, red wine, or another acidic item. This helps prevent coagulation when heating blood in soups as well. But there’s little information on what any of these processes ends up doing to the compounds inside of a given blood, and thus to its flavor. 

As the metallic taste of blood is its most offensive characteristic to many eaters, chefs have developed a trove of culinary lore about what either mellows out or neutralizes that flavor. Milk or cheese, coffee, chocolate, citrus, and sugar are especially common fixes. (Knorr says that milk is a secret weapon for neutralizing the iron-y flavor of overcooked offal dishes as well.) But you’ll also find recipes that assert that all of the following can counteract metallic notes (deep breath): aniseed, cardamom, cinnamon, clover, cloves, dill, fennel, ginger, juniper, koji, mint, marjoram, nutmeg, parsley, rosemary, sage, thyme, and woodruff. A list that basically boils down to any potent spice

Davies points out that these pairings are similar to those used for game meats in many parts of the world. McLagan argues that sugar and citrus especially are so effective that you can’t taste the blood in her blood-drenched gelato or marshmallow recipes—just an earthiness that reads as dark chocolaty. Paul agrees that sugary-spicey baked goods are especially effective blood maskers. This may be why so many children in the Soviet Union and post-Soviet states grew up eating cow’s blood-laced nutritional sweets called Hematogen without ever realizing they contained blood. Only some people remember them having a strong twang of iron. 

However, McLagan stresses that people’s priority in cooking with blood shouldn’t always be looking for ways to hide it—to turn it into a sneaky source of protein or binding. Sometimes you want to highlight the blood in your dish. Either because you want to make a red or brown color pop. Or because you want its creamy coagulated texture. Or because you’re cooking for someone who appreciates a little earthy, metallic punch to their food. Perhaps you even think you can win someone over to the gorey world of sweet, gamey, metallic flavors with the right one-two combo of compounding umami, as in a good savory blood sausage, terrine, or ragu. Or of sweets and iron, as in a solid Italian blood treat—like the tantalizing Sardinia blood, ground walnut, and chestnut flour fritters Davies describes. She says they’re usually flavored with raisins, pine nuts, cloves, and cinnamon, and drizzled with honey. 


Whatever you’re aiming for, you’ll probably have to do a little experimentation to figure out what works for your palate, or those you’re serving. And with the specific ingredients you have to hand. That’s what Uttmark had to do when they first started experimenting with sagnuinaccio dolce recipes after seeing the dessert in an episode of Hannibal: The first recipe they tried proved too grainy and metallic for their taste, so they played around with ratios, ingredient orders, and sourcing until the dish came out just right. Turned into something to convert the non-believers. 

Whatever path you go down with this newfound knowledge of how to cook with blood, Davies urges everyone to remember: “Eating blood in the form of sausages, crepes, chocolate puddings, or anything else should bring people a sense of joy and satisfaction, because it is delicious and comforting. Because they are helping to preserve culinary traditions. And because they haven’t allowed this perfectly edible protein to go to waste,” having found the full potential within it. 


About the Author

Mark Hay is a Brooklyn-based freelance writer. His work has appeared in Atlas Obscura, Forbes.com, VICE, and dozens of other outlets. You can find more of his articles on blood, and many other topics, here.