Sufu: History, Fermentation, and Culinary Heritage

Open a jar of sufu, and you meet tofu in another form. The cubes are soft to crush with a spoon, while their brine carries aromas of wine, salt, soy and fermentation.

Often called fermented bean curd, sufu is not spoiled tofu and not merely tofu preserved in salt. It is a deliberately fermented and ripened food whose depth comes from microorganisms, enzymes, time and regional craftsmanship.

What Is Sufu?

Sufu is the name widely used in English-language food science for a family of Chinese fermented tofu products. In Chinese, furu or doufuru is often more familiar. Names vary across dialects and communities: Cantonese speakers may know it as fu yu or nam yu, while related traditions travelled beyond mainland China, including Vietnamese chao and Okinawan tofuyo.

Despite the nickname “Chinese cheese”, sufu is not dairy cheese. The comparison describes its concentrated flavour, creamy body and microbial ripening. Its foundation remains tofu: soy milk is coagulated, formed into curd and pressed before fermentation begins.

A Food Shaped by Preservation

Written references to sufu reach back at least to China’s Wei dynasty, from 220 to 265 CE. Its development answered a practical problem. Fresh tofu is moist and perishable; fermentation, salt and alcohol could extend its usefulness while creating flavours impossible in the fresh curd.

Over centuries, sufu became everyday food rather than a luxury. A cube beside congee could enliven an otherwise plain breakfast. Its intense seasoning made modest quantities valuable, and local dressings turned a preservation method into a diverse culinary tradition.

How Tofu Becomes Sufu

Production usually unfolds in two major fermentative stages. First, pressed tofu is cut into cubes, drained and inoculated with selected moulds, traditionally species associated with genera such as Actinomucor, Mucor or Rhizopus. Under controlled warmth and humidity, fine fungal mycelium grows around the cubes. This intermediate is often called pehtze.

The visible growth is only the beginning. Fungal enzymes, particularly proteases and lipases, start breaking large soy proteins and fats into smaller compounds. The cubes are then salted and transferred into a maturation dressing that may contain brine, rice wine, fermented rice, spices or other seasonings.

During weeks or months of ageing, enzymes continue working even as salt and alcohol restrain many microbes. Proteins release peptides and amino acids, including compounds that contribute savouriness. Fats yield fatty acids, while interactions among acids, alcohols and other metabolites create aromatic esters. The tofu’s firm gel gradually becomes smooth, cohesive and spreadable.

This is why sufu tastes larger than its ingredient list. Fermentation does not simply add mould flavour; it reorganises the curd’s texture and generates layers of saltiness, sweetness, umami, warmth and lingering aroma.

White, Red and Regionally Distinct Styles

White sufu is typically pale cream or yellow, with a salty, wine-like and strongly savoury profile. It is perhaps the clearest expression of ripened tofu itself.

Red sufu gains its brick-red colour and distinctive fragrance from red fermented rice, commonly made with Monascus cultures. Often called nam yu in Cantonese cooking, it can be sweeter, fuller and more aromatic than many white styles. It is especially valued in braises, marinades and sauces.

Chilli sufu adds heat through fresh or dried chillies, chilli paste or oil. Other jars may incorporate sesame oil, sugar, spices or fermented rice mash. Grey sufu, associated particularly with Beijing, is more pungent and visually austere. These are not merely colours on a shelf: each style reflects local ingredients, tastes and methods.

Okinawan tofuyo shows how the idea evolved through cultural exchange. Traditionally matured with awamori and red koji, it is intensely flavoured, creamy and commonly eaten in tiny portions. It belongs to its own Ryukyuan tradition rather than being simply another Chinese jarred sufu.

How Sufu Works in the Kitchen

Sufu is best understood as a concentrated seasoning, not a tofu portion. Begin with half a cube, mash it with a little liquid from the dish, then taste before adding more. Its salt level varies substantially among brands and styles.

For the simplest experience, spread a small dab over hot rice, steamed buns or congee. In sauces, whisk it with water, stock, sesame paste or vinegar for noodles, hot pot or blanched vegetables. White sufu gives stir-fried water spinach a savoury backbone; red sufu brings colour and fermented complexity to slow braises.

It can also season tofu itself. Blend a restrained amount into a glaze for roasted firm tofu, loosen it into a mushroom sauce, or mix it with garlic, ginger and a touch of sweetness. Add other salty ingredients only after tasting. The goal is not to make everything taste of sufu, but to let its depth connect the dish.

Buying, Storing and Using It Safely

Choose commercially produced sufu in an intact, properly sealed jar and follow its label. After opening, refrigerate it if directed, keep the cubes submerged, and use a clean utensil. Discard the product if the seal was compromised or if you notice unexpected gas, leakage, abnormal growth or an odour clearly different from its usual fermented pungency.

Because sufu is salty, a little usually suffices. Fermentation may alter proteins, flavour compounds and the availability of some nutrients, but it does not automatically make the finished product probiotic; salt, alcohol, ageing and processing affect microbial survival. It should be appreciated as a condiment, not marketed as a cure.

Making traditional mould-ripened sufu safely requires controlled cultures, sanitation, temperature, humidity, salt and maturation conditions. Letting tofu mould spontaneously at home is not equivalent to an established process and can invite unwanted organisms.

Final Takeaway

Sufu captures tofu’s power to carry culture as well as flavour. Born from preservation knowledge, it turns a mild, fragile curd into something durable, concentrated and regionally expressive.

Its lesson is not that tofu needs disguise. It is that tofu can change profoundly while remaining itself. One small cube holds soybeans, skilled fermentation, migration and memory—and proves that culinary power is often measured not by quantity, but by depth.