The cooked sticky rice lies in a thin, glossy layer across the tray, and once it has cooled, a fine pale dust of crushed men ngọt falls over it from the sieve. A few minutes later the rice is pressed into small, firm balls with salt-wet hands, packed into a lidded pot and left alone. About three days on, the pot gives off a fragrance, and that is the signal to move it to the refrigerator. Cơm rượu is fermented glutinous rice, and this is one home cook's southern way of making it: plain white sticky rice, shaped into soft, moist little balls, with nothing sweet poured over them.
Đoan Ngọ Morning and the Southern White Rice Ball
Fermented sticky rice belongs to Đoan Ngọ, the fifth day of the fifth lunar month. On that day, rượu nếp, fermented sticky rice, is set out among the offerings to the ancestors, and it shares the festival table with bánh tro. The author of the southern recipe used here remembers eating cơm rượu with bánh tro for breakfast on Đoan Ngọ morning with their mother, and in that family the rice went into its pot three to four days before the festival.
The fermentation sets the rhythm of the week. Rice is soaked, cooked, cooled, dusted with starter and shaped in one sitting, and then the pot sits closed while the days count down to the holiday. By the morning itself, the work is long finished and the only thing left is to lift the lid.
Đoan Ngọ morning goes by the phrase giết sâu bọ, a festival name and belief that the recipe's author mentions. It belongs to the calendar and the customs of the holiday, not to any claim about health or about what the dish does.
White balls, purple rice and other households
This is the southern white version: white glutinous rice, a starter called men ngọt, salt and water, and the rice shaped into small balls before it ferments. Other households make it differently. Some use purple sticky rice for a dark, separate version, some pour a sugar syrup over the finished rice, and some work the starter into the rice with their hands before shaping. Each of those is its own recipe with its own proportions.
Sticky rice runs through much of Vietnamese cooking, and cơm rượu sits apart from its neighbours. Cơm lam steams the rice in bamboo tubes and leaves, and bánh chưng wraps it around mung beans and pork in leaves. Neither is fermented. Cơm rượu is the one where a starter does the cooking after the heat is off. More dishes from the same kitchens are on the Vietnam page.
Ingredients
The teaspoon of coarse salt belongs to the soaking water and nowhere else. The hand water gets its own salt in its own bowl. Keeping them apart keeps the soak and the shaping each doing their own job.
Equipment
- Rice cooker
- Bowl for rinsing and soaking the rice
- Mortar and pestle
- Small separate bowl for the hand water
- Clean tray
- Rice paddle
- Fine sieve
- Ceramic, porcelain or glass container with a tightly closing lid
- Refrigerator space for the container
Buying Rice and Men ngọt
Glutinous rice is sold as sticky rice or sweet rice at Asian grocers and in many supermarkets' rice aisles. Choose white grains for this version; purple sticky rice belongs to a different cơm rượu.
Men ngọt is the decisive purchase. It comes as small, dry, pale balls and is sold at Vietnamese and other Asian grocers and online. Buy only men ngọt sold as food, in sealed retail packaging. Bread yeast, instant yeast and koji are different products, and using any of them turns this into a different dish, so the starter stays as it is. Coarse salt is ordinary coarse cooking salt from any grocer.
Method: Soak, Cook, Cool, Shape, Seal
The work happens in one session and then the pot does the rest. Soak the rice first; during the two-hour soak there is time to set out the tray, sieve, mortar and container. After cooking, the rice must cool on the tray before any starter touches it, and the hand-water bowl is prepared before the rice is spread. Once the pot is sealed, the hands-off stretch is about three days. In Japan, making a drink of 1% alcohol or more at home without a licence is restricted by the Liquor Tax Act, so readers there should check the rules or enjoy cơm rượu where it is made.
Wash your hands and use a clean container, tray, sieve and mortar. Keep to the salt and the timing in the steps. Throw the whole batch away if it smells wrong, grows mould or turns an unexpected colour.
The starter goes onto rice that has finished cooling, and it goes on top as a fine, even dusting. Sifting it over the surface, without stirring it in, is how this version spreads the starter before shaping.
When It Goes Wrong
| What you see | Why | What to do |
|---|---|---|
| Hard crumbs of starter stay in the sieve | The men ngọt was not crushed fine enough | Tip the crumbs back into the mortar, grind to a fine powder and sift again |
| Rice sticks to your palms while shaping | Your hands have dried | Re-wet them in the hand-water bowl and shake off the excess |
| Balls slump or crack apart | The rice was pressed too loosely | Re-press each ball firmly between damp palms until it holds its shape |
| Starter heaped in some spots, bare in others | The sieve stayed still over one place | Sift the remaining powder over the bare patches, moving the sieve steadily |
| Mould, an unexpected colour or a wrong smell in the pot | The batch has gone off | Throw the whole batch away and start again with a clean container |
Serving, Other Versions and Keeping
At the table
Serve a few balls in a small shallow dish, plain, the way they come out of the pot. In the recipe author's memory they sit beside bánh tro for breakfast on Đoan Ngọ morning, and fermented sticky rice is among the offerings set out for the ancestors that day. In the recipe author's family, the rice went into the pot three to four days ahead of the festival.
Other versions
Purple sticky rice gives a darker cơm rượu with its own recipe and proportions. Some households pour a sugar syrup over the finished rice, which turns the plain fermented balls into something sweet and saucy. Others mix the starter into the rice by hand before shaping instead of sifting it over the top. The white southern balls here keep the rice plain and let the fragrance of the ferment carry it.
Keeping
Keep the cơm rượu in the refrigerator, in its container with the lid closed. Take out only what you will serve and close the pot again straight away. If it smells wrong, grows mould or changes colour, throw it away.
Frequently Asked Questions
Do I need an oven or a heating pad for the fermentation?
The method gives no temperature and lists no oven or heating pad. It asks for a warm spot in the kitchen and about three days with the lid closed. Keep the pot in one place and check for the fragrance when the days are up.
Which container works best, ceramic or glass?
Ceramic, porcelain and glass all work. What matters is a clean container with a lid that closes tightly. Choose one big enough to hold all the balls side by side with the rim clear.
Can I make it with purple sticky rice?
Purple sticky rice makes the other, darker version of cơm rượu, with its own proportions. For the white southern balls, use white glutinous rice and keep the amounts in the table.
