In overseas Chinese communities living in Southeast Asia, commercially packaged versions are often sold in jars containing blocks 2- to 4-cm square by 1 to 2 cm thick soaked in brine with select flavorings.
A clear reference to fermented tofu appeared in the 1610 Penglong Yehua (蓬櫳夜話), under the name haifu (醢腐).
[5]: 18 In 1818, Englishman Basil Hall wrote about a red, cheese-like substance served in Ryukyu; he might be referring to fermented tofu.
[5]: 5, 23–4 In Mandarin, the product is generally known as dòufǔrǔ (豆腐乳), "dòurǔ" (豆乳) or fǔrǔ (腐乳) — though in southwest China it is often known as lǔfǔ (卤腐).
Red fermented bean curd contains much larger amounts of alcohols, esters, and acids than the white variety.
The Food Encyclopedia, written by Wang Su-Hsiung (1861) of the Qing dynasty, made reference to preserved bean curd as superior to difficult-to-digest, hardened tofu especially for the elderly, children, and ill persons.
[9] It has been suggested that fermented bean curd may have certain health benefits, although there is insufficient data to confirm these claims.
[11] The texture and taste of fermented bean curd resembles a firm, smooth paste not unlike creamy blue cheese.
Fermented tofu is commonly used as a condiment, combined into sauces to accompany hot pot, or consumed at breakfast to flavor rice, porridge, gruel, congee, or erkuai.
In the Chaoshan region of China, fermented tofu is the main ingredient used to make a stuffed biscuit known as furu bing.
allowing protein bonding while cheese curds are created from the enzymatic (rennet) hydrolysis of casein into para-casein.
Red fermented bean curd (紅腐乳; hóngfǔrǔ, or 南乳; nánrǔ) incorporates red yeast rice (cultivated with Monascus purpureus) with the brining liquor for a deep-red color and distinctively thickened flavor and aroma.
A popular derivative of this variety has an appearance of ketchup and is seasoned with rose wine, caramel and natural sugar.