Jiuniang (sweet fermented glutinous rice)

What jiuniang is

Jiuniang (酒酿) is sweet fermented rice. Glutinous rice is steamed, mixed with a dry starter called jiuqu and left warm for a day or two, and by then the grains have gone soft and the bowl holds a pale, sugary, faintly boozy liquid. It is neither plain cooked rice nor a clear rice wine. The grains and the liquid are eaten together, usually with a spoon, and the texture runs from separate tender grains in syrup to a looser, porridge-like mass. The taste is sweet first, then a little tart, with the winey aroma of fermented rice.

What sets it apart is the stage at which it is stopped. Starch in the rice has been broken into sugar, some of that sugar has become alcohol, and the cook takes the bowl while most of the sugar is still there. Left longer, the same rice turns drier, more acid and stronger, and moves toward the cloudy rice wines that are strained and drunk. Jiuniang is a food that happens to be alcoholic, not a drink that happens to be sweet.

The starter makes this possible. Jiuqu is a dried cake or powder of microbes grown on rice or flour, and the useful members of the mixture do different jobs. Moulds, above all Rhizopus, produce the enzymes that cut starch down to glucose. Yeasts turn part of that glucose into alcohol and carbon dioxide. Lactic acid bacteria add a little acid. Ordinary baker's yeast supplies only the yeast part, so it cannot turn cooked rice into jiuniang on its own.

The same food goes by many names. Jiuniang is the common term in eastern China, and laozao (醪糟) is the one heard in Sichuan, Chongqing and much of the north. Tianjiu (甜酒) means sweet wine, and tianjiuniang, nuomijiu and jiangmijiu are other labels, some of which also cover thinner or stronger rice wines. Jiuzao (酒糟) can mean the leftover grain from brewing rather than the finished dessert. The words overlap without being perfect synonyms, so a recipe should be read for what it does with the rice, not only for its name.

A sweet brew with a long, hazy past

Chinese writers have recorded sweet grain brews for two thousand years, but the food now called jiuniang cannot be traced back along a clean line. The strongest early candidate is the tujiu of the Shu people, set down in the Qimin yaoshu, the sixth-century farming handbook of Jia Sixie. Its recipe steeps a barley ferment in water in the twelfth month and seals the urn with mud. In the first or second month, when the thaw comes, the liquid is filtered, and part of it is mixed with cooked saccharified rice, resealed and left for ten days. It is eaten together with the dregs and is described as sweet, pungent and smooth, with little power to intoxicate. That is close to jiuniang in outline, though the starter, timing and sealing differ from the modern food.

Older still are the laoli and laoyao of the Huangdi neijing, the Han-period medical classic. Lao was defined in the ancient dictionary Shuowen Jiezi as a brew that keeps its dregs, and li as a sweet brew without them, so a compound of the two can be read as a sweet rice brew with its grains. Scholars such as Nicholas Tursi treat these passages as likely forerunners. They stop short of calling them jiuniang, because the texts do not describe starter, rice or method closely enough to say.

The name jiuniang itself turns up in the Qing period. Zhao Xuemin wrote his Bencao gangmu shiyi in the middle of the eighteenth century as a supplement to the Ming materia medica, and gave jiuniang a place in Book 8 among the grains. One recipe there boils five jin of jiuniang with sealwort, wolfberries and millet wine in a jar for the time it takes an incense stick to burn. That is a medicinal use, and it shows that by then jiuniang was a named, familiar material. It is also a ceiling for what the texts can prove, not a date of invention.

Part of the silence is social. Jiuniang is rustic home food made with a few cheap things, and the literati who wrote the books seldom recorded it. A small jar needs only rice, starter, water and time, so households could keep making it without leaving a trace. Later regional histories add local colour, such as the Xiaogan shop Luyuanxing, founded in 1924 by a former rice wine peddler, and the Fuling dish youlaozao dated to 1799. They record how the food was used in particular places, not how old jiuniang is.

How the rice becomes sweet and a little alcoholic

Raw rice starch is packed in hard granules that enzymes cannot easily reach. Steaming with water swells and bursts the granules, which is called gelatinisation, and that is why the rice is cooked before the starter goes in. Glutinous rice is almost all amylopectin, the branched form of starch. It cooks soft and sticky, and its many branch ends give enzymes plenty of places to work.

The starter's moulds do the first job. Rhizopus species release alpha-amylase, which chops long starch chains into shorter pieces, and glucoamylase, which strips glucose from those pieces one at a time. The grains soften as the starch leaves them, and the liquid around them fills with sugar. This saccharification is why jiuniang can taste so sweet while it ferments: sugar is released faster than the yeasts use it. A 2025 sequencing study of one batch found Rhizopus and the yeast Wickerhamomyces anomalus in command from start to finish, and measured 33 degrees Brix of soluble solids alongside 3.5 per cent alcohol and a pH of 3.75 after 43 hours.

Yeast then turns glucose into pyruvate and, through acetaldehyde, into ethanol and carbon dioxide. Saccharomyces cerevisiae is the best-known worker, but starters also carry other yeasts. Studies of jiuqu have isolated Saccharomycopsis fibuligera, Wickerhamomyces anomalus and Torulaspora delbrueckii, and a co-fermentation with Saccharomycopsis and Rhizopus produced more volatile compounds, among them more esters and higher alcohols, than the mould alone. Those compounds are the fruity, winey notes of the finished rice.

Bacteria join in too. A 2023 survey of laozao from Liquan County in Shaanxi found Lactobacillus making up 85.25 per cent of the bacterial sequences, with Pediococcus, Leuconostoc, Streptococcus and Lactococcus beneath it, and among the fungi Rhizopus at 56.66 per cent, Saccharomyces at 23.28 and Saccharomycopsis at 12.24. Samples from the same county split into two significantly different groups, so even one named local product is not a fixed recipe, and gene sequences count DNA, not living or working cells. In a controlled test, adding Lactobacillus rhamnosus raised acidity and made lactic acid the main organic acid, while extra Saccharomyces cerevisiae raised ethanol. Starter enzymes can also free amino acids from the rice proteins, which feed the microbes and add flavour. Sweetness, alcohol, acid, softened grain and aroma all come from several organisms working at once.

Making it, and why each stage matters

There are only three ingredients: glutinous rice, starter and water. The rice is the whole source of sugar, so no sugar is added. Glutinous rice is chosen because it stays soft and cohesive when cooked and still keeps its grains. The starter brings the organisms and enzymes. Water lets the starch swell during cooking and then lets enzymes and microbes move through the bowl.

The Hunan government's recipe for the sweet rice in tianjiu chongdan is a good plain model. Soak 350 g of glutinous rice for two hours, steam it for 30 minutes, sprinkle on a little hot water and steam 15 minutes more. Rinse with cold water until the rice is no longer too hot to handle, drain it well, mix in 2.5 g of jiuqu powder, press the rice into an earthenware bowl and cover it. The bowl is held at 30 C for 34 hours.

Each stage has a purpose. Soaking lets water enter the grain so the middle cooks as well as the outside. The second, moistened steaming finishes cooking without turning the rice into porridge. Rinsing with cold water stops the cooking and cools the rice to a point the starter can survive, because hot rice would kill the moulds and yeasts; it also loosens clumps so the starter reaches every grain, and draining keeps a puddle of water from diluting the sugar. A steady 30 C suits the Rhizopus and yeasts of the starter, and in the hours that follow saccharification runs ahead of fermentation.

Other published methods show how much latitude the food has. A Chongqing account cools the rice to about 35 C, adds the starter in batches and presses a small hollow into the centre, so the syrup gathers there and the cook can see it. The bowl is wrapped to stay warm and the laozao is ready in about three days. A 2025 research batch soaked 1,000 g of rice for 12 hours, steamed it for 60 minutes, cooled it to about 30 C, used 4 per cent starter by dry rice weight and fermented at 28 C, and the panel judged 43 hours best. A 2024 experiment soaked overnight at 25 C, steamed 30 minutes, added water at 1:0.8 and a Rhizopus-bearing leaven at 500:1, and ran 72 hours at 30 C. Their times and ratios belong to their own set-ups and should not be pooled into one recipe.

The Hunan recipe prints 34 hours at 30 °C as its production setting. A separate 2025 experiment at 28 °C used a flavour panel that preferred its own 43-hour sample to a 48-hour sample. Neither result is a validated safety endpoint or a timing rule for another starter and batch. Sweetness, soft grains, syrup and a pleasant smell describe quality changes; they do not rule out pathogens or toxins. Refrigeration can slow further fermentation but does not supply a tested household shelf life.

Regional forms and uses

Jiuniang is better thought of as a family than as one fixed product. Regions differ in the rice, the starter, the amount of water, the length of the ferment and the way the grains are finally eaten. Hubei's Xiaogan is the best-documented local form. Its rice wine is made from Zhuhu pearl glutinous rice and a honeycomb-shaped starter, soaked, washed, drained, steamed, cooled to lukewarm, mixed with the starter and left in vats or jars. Local tradition ties it to the Song emperor Zhao Kuangyin, who in the story was rescued by a bowl of it, and a Qing county gazetteer line says the wine was perfected in Xiaogan and began in the Song. The rice wine is a fixture at weddings and festivals, and a thick-soup version is a street breakfast. Hubei lists the craft among its provincial traditional crafts.

Chongqing and neighbouring Sichuan favour the name laozao. Fuling, a town on the Yangtze, is known for youlaozao, in which fermented rice is stir-fried in lard with peanuts, black sesame, walnuts and candied fruit into something richer and sweeter than the plain rice. The local gazetteer dates the dish to 1799, with a story about a cook who had no time to make dumplings for an important household and served sweet fermented rice with eggs instead. It is a cooked speciality built on jiuniang, not the same food.

In Hunan the rice goes into tianjiu chongdan, a hot sweet soup poured over beaten egg. In Shanghai, shops such as Guxingsing sold osmanthus sweet jiuniang and jiuniang yuanzi, with eight-treasure rice, before merging into the Songyunlou shop on Yuyuan Road. Colour changes the food too: a 2023 experiment on black glutinous rice followed sugar, alcohol, acidity and colour through the ferment and saw alcohol peak at 6.24 per cent on day five, higher than the figures usually quoted for white-rice jiuniang. Selected yeasts and lactic bacteria added in laboratory trials are research variants, not inherited household methods.

How it is eaten and cooked with

The simplest way to eat jiuniang is straight from the jar, cool or gently warmed, grains and liquid together. Cooks also stir a few spoonfuls into hot water for a quick sweet rice soup. The best-known dessert is jiuniang yuanzi, a bowl of the fermented rice with small glutinous rice dumplings, often scented with osmanthus. The fermented rice goes in at the end of cooking, once the heat has dropped, so the aroma survives.

Eggs are the usual partner. In Hunan's tianjiu chongdan, the cook boils a thin paste of glutinous rice, stirs in half of the sweet rice, cracks eggs into the bowls and pours the boiling liquid over them so the egg sets in silky strands. The remaining cold sweet rice is spooned in with osmanthus sugar, sugar and crushed dried longan, and the recipe makes ten bowls. In Chongqing laozao is simmered with poached eggs or dumplings, and in Fuling the fat-rich youlaozao follows the same logic.

Jiuniang has savoury uses too. Chinese cooks put it into marinades and braises, where it adds sweetness, a little acid and a ferment aroma, and it can stand in for cooking wine in some dishes. Because it already carries sugar, a cook has to cut the sugar elsewhere. Food scientists have even studied it as a source of natural enzymes in bread: a 2017 paper tested fermented glutinous rice as a natural enzyme mixture to improve dough and slow staling.

It is also eaten as a tonic. Chongqing writing records laozao with eggs or brown sugar for new mothers and older people, and the Shenzhen regulator notes that postpartum dishes of sweet rice wine with egg are common. Health agencies in Hami and Beijing's Haidian district say plainly that small amounts of rice wine or laozao do not increase milk, and that alcohol reaches a breastfed baby. The custom is part of the food's social history, not a reason to eat it for recovery.

Reading results and problems

Several signs show that the ferment is working: the rice softens, liquid collects around it or in the central hollow, the smell turns sweet and winey. They show that starch is breaking down. They do not show that the batch is safe, and a sweet smell cannot rule out a pathogen. Sugar, acidity and alcohol, when measured, say more than taste does. The measured values in the literature are examples. A laboratory batch at 43 hours gave 33 degrees Brix, pH 3.75 and 3.5 per cent alcohol; the black-rice batch reached 6.24 per cent; a classic description puts jiuniang near 1.5 to 2 per cent, while rice wines on the market are said to run roughly 3 to 14 per cent and one experiment reached about 14 per cent after 96 hours. These are not targets.

Too sour a bowl usually means too long, too warm or too much lactic acid from the starter. The 2024 experiment showed that extra Lactobacillus raises acidity, and extra yeast raises alcohol, so a batch that tastes sharp or hot has moved past the sweet stage. A bowl that stays hard and dry may have been undercooked, cooled so far that the starter hardly worked, or inoculated with a dead starter. Plain baker's yeast does not rescue it because it does not break down the starch.

The main safety question is the rice itself. Bacillus cereus spores survive cooking, and rice that is cooked, cooled slowly and held warm is the textbook setting for their growth and toxin. Laboratory work with cooked rice found the emetic toxin forming at 15 to 45 C and surviving two hours at 100 C, so boiling a doubtful batch does not help. Jiuniang adds a warm incubation on purpose, which is why a working starter, clean equipment and prompt handling matter, and why ordinary advice about cooking and chilling rice cannot simply be reused for it. Unexpected coloured mould, a putrid smell or growth that does not look like the white mycelium of the starter calls for throwing the batch away.

Jiuniang is also alcoholic. Alcohol content has no national standard, rises with time and warmth, and the sweetness hides it. It is not an alcohol-free dessert for children, nor for pregnancy or breastfeeding. Storage is not settled either: cold slows fermentation without stopping it, and sealed jars can build pressure. No safe shelf life, pH limit or minimum alcohol is established for home batches.