One Pour of Near-Black Cuko, and Fish Cake Tastes Like a Street Stall
Cut a freshly fried fish cake open and only the outside is thinly crisp, while the inside is white and chewy. Pour over a sweet-sour sauce so dark it is nearly black, and out of the steam rise tamarind, garlic, chili and palm sugar. Why cucumber sits beside it, and why a little yellow noodle joins it, becomes clear in the mouth: the fish's savor, the springy starch and the sauce's acidity all need something fresh to catch them.
Pempek is the signature fish-and-starch dish of Palembang, South Sumatra, Indonesia. It is also written mpek-mpek or empek-empek locally. At its base, ground fish and a dough made with sago or tapioca are boiled, fried before serving, and paired with a sweet, sour, spicy sauce called cuko. It comes in many shapes, such as kapal selam with an egg inside, long lenjer and round adaan, and you meet it at street stalls and as a souvenir.
When cooking it abroad, the hard part is less choosing the fish than tightening the dough. Locally, fish with springy flesh such as tenggiri is often mentioned, but in a home kitchen it is more realistic to use fresh cod, pollock, swordfish, frozen surimi or white fish fillets. Too much tapioca starch makes it hard as a rubber band, and too little fish makes it a flour dish. This recipe uses a ratio that keeps the fish flavor while still letting you shape it, making kapal selam and lenjer from the same dough.
Unlike a rich meat dish such as sate Padang (in Japanese), pempek centers on fish and a light acidity. In its use of sago or tapioca starch, it is distantly related to eastern Indonesia's papeda (in Japanese). Keep a jar of the sweet-sour black sauce and the next day it goes on grilled fish, boiled eggs and cucumber, which is what makes it worth making at home.
Pempek is the Indonesian spelling. Around Palembang it is also called mpek-mpek or empek-empek. Cuko is spelled close to the local pronunciation.
Background: River Fish, Sago and Palm-Sugar Sauce
Pempek is not just a fried fish paste. A paper in the Journal of Ethnic Foods sets out how Palembang's history, geography, fish resources and the trade in sago and palm sugar shaped the making of pempek and its food culture. Indonesia's tourism ministry's English introduction also presents it as a South Sumatran dish from Palembang that combines fish, tapioca starch and cuko.
Cuko is not just a sauce on the side of the plate; it is what makes pempek pempek. Palm sugar, water, tamarind, garlic and chili are simmered together to unite sweet, sour, spicy and the sharpness of garlic. Local introductions also show it served with cucumber, yellow noodles and dried shrimp powder. At home you can skip the dried shrimp powder, but try not to leave out the cucumber. It puts a cold crunch between the oil and the acidity.
| Local element | Role | Practical home choice |
|---|---|---|
| White fish such as tenggiri | Savor and springiness | Fresh cod, pollock, swordfish, frozen surimi |
| Sago, tapioca | Chewy dough | Tapioca starch as the base; don't overdo it |
| Cuko | Sweet-sour, spicy sauce | Tamarind, palm sugar, garlic, chili |
| Kapal selam | A large shape with egg inside | Wrap a small amount of beaten egg, not a whole boiled egg |
| Lenjer | Long shape | Good for a first try. Holds its shape |
Egg-filled kapal selam is a fun shape, but making every piece with egg from the start makes them burst. For a first batch, make 70 percent of the dough into long lenjer and use the rest for two egg-filled pieces, so the table works even if those fail.
Ingredients: Fish Cakes, Cuko and Accompaniments, Measured Separately
This serves 4. As a main dish use this quantity; as a snack it serves six to nibble on. Wet white fish makes the dough slump. If you use fillets, press them well with paper towels before weighing.
This dish contains fish and eggs, and depending on the product may contain wheat, soy and shrimp. If you use dried shrimp powder or commercial surimi, check the ingredient labels. Because it is made from fish paste, cook it through to the center by boiling and frying.
Shopping: Fish Nearby, Starch and Tamarind from Specialty Sources
Use white fish you can buy at an ordinary supermarket. Rather than a pricey fish, it matters more for the result to press out moisture, mix it cold and not overdo the tapioca starch. The things worth sourcing from a specialty or online shop are tapioca starch, tamarind paste and a thermometer to keep the oil steady.
Tapioca starch decides pempek's springiness. Potato starch alone will also set it, but it tends to turn gritty when cool and moves away from pempek's chewy bite. Tamarind is the core of cuko's acidity. It can also go to the same table as gado-gado and a sambal substitute.
Cuko with dark sugar alone is merely a sweet sauce. Once the sourness of tamarind goes in, the fried fish cake suddenly moves toward Palembang. Pickled plum and lemon can make sourness too, but the aroma is different.
Pempek is boiled once and then fried. The inside is already cooked, but if the frying oil is too cool the surface turns greasy, and too hot only the outside burns. For a first attempt, a thermometer makes it easier to find the point around 170°C where the surface lightly colors and the springiness returns.
Method: Mix Cold Fish, Boil, Then Fry
Fish dough is not better the more you knead it. Develop stickiness with salt, and fold in the tapioca starch only at the end. Kneading long after the starch goes in gives a hard, packed texture.
Kapal selam holds an egg, so if the water dances vigorously the seam splits. Bring the water to a boil, then lower it and keep the heat at a level where the pempek floats quietly. If one splits, don't force it closed: boil it through as is, fry it, slice it and pour on extra cuko, and it still comes together at the table.
Decision Table for Approaching the Original in a Home Kitchen
With pempek you succeed more by protecting the amount of fish, the amount of starch and the acidity of the cuko than by hunting for the same fish used locally. Moving the name toward the original does not help; if the dough is too hard, it becomes a different food.
| Where you hesitate | Direction to protect | Practical home choice | Direction to avoid |
|---|---|---|---|
| Fish | Mild white fish with springiness | Fresh cod, pollock, swordfish, frozen surimi | Using only a strongly fatty fish |
| Starch | Chewy but not too hard | Adjust from 220 g tapioca starch | Adding starch only to shape more easily |
| Moisture | Develop stickiness while cold | Add ice water in portions | Rescuing a slumped lukewarm dough with starch |
| Acidity | Tamarind's dark sourness | Use tamarind paste | Making it shallow with vinegar alone |
| How to eat | Lighten it with cuko and cucumber | Yellow noodles, cucumber, a small bowl of cuko | Serving fish cakes without sauce |
For your first time at home, prefer reliability over looks. Lenjer is just long, so the boiling time is predictable and the cut face takes the cuko easily. Kapal selam raises cheers at the table, but you have to watch the amount of egg, the seam and the heat of the water all at once. A good first batch is mostly lenjer with just two egg-filled pieces mixed in.
In local photographs, various shapes mix on a single plate. At home too, you don't have to match them all. Slice the long ones on the diagonal after frying, and cut the egg-filled ones large and set them in the center. Spoon cuko over a little at a time and always put cucumber beside them. In this order, the springiness of the fish, the softness of the egg and the sourness of the black sauce change with each bite, so it doesn't end as a heavy flour dish.
Surimi may already contain salt. Read the ingredient label, and if it seems salty, reduce the salt to up to 1 tsp. Frozen surimi releases water when thawed, so pat it with paper towels before using. With fish fillets, remove skin, blood line and small bones, and process it right after taking it from the refrigerator to keep the smell down.
If tapioca starch is too little it is hard to shape, and too much makes it hard. If the dough is sticky, don't add starch all at once: oil your hands, chill the dough for 10 minutes and then touch it. Only if it still slumps, add tapioca starch 1 tbsp at a time. Remember that each addition tightens the texture a little.
What Goes Wrong: Hard, Splitting, Heavy Cuko
When pempek is hard, there is too much starch or it was kneaded too long after the starch went in. Next time reduce the tapioca starch to 200 g and make the fish paste while it is cold. For pieces that are already hard, slice thin before frying and pour on extra cuko; adding cut surfaces holds the sauce better than eating them thick.
When they split during boiling, you put in too much egg, the seam is thin or the water is too vigorous. Kapal selam is hard to handle when large, so make no more than two egg-filled pieces the first time. Stop the beaten egg at 2 tbsp and, after closing, pinch the dough lightly to build thickness.
If the cuko is heavy, it has been reduced too far. Add 2 tbsp water, 1 tsp rice vinegar and 1/2 tsp tamarind, and warm over low heat for just 1 minute. If it is thin, simmer 2 minutes at a time over low heat. Adding only sugar makes the fried food heavy, so adjust sourness and salt a little at a time.
If the fish smell bothers you, check the freshness of the fish, its moisture and the amount of garlic. Rather than masking with sake, keeping the fish cold while you work and putting tamarind and garlic properly into the cuko makes it hang together as pempek.
Storage and Reheating: Stop at the Boiled Stage
If making ahead, stop after boiling, not after frying. Drain the boiled pempek, let it cool, and put it in an airtight container. Plan on refrigerating until the next day, or freezing for 2 weeks. When freezing, wrap each piece in plastic wrap so they don't stick.
Refrigerated pieces: pat the surface dry, warm in 160°C oil for 1 minute, then raise to 170°C and fry 1 to 2 minutes. Frozen ones: half-thaw in the refrigerator and fry in the same way while the center is still slightly firm. Reheating by microwave alone softens the surface, but that is acceptable if you pour cuko over for a snack.
Cuko keeps about 4 days refrigerated. It contains garlic and chili, so keep it in a clean jar and take out only what you need into a small dish. The aroma closes up when cold, so warm it in a heatproof container at 600 W for about 20 seconds before eating to bring back the aroma of palm sugar and tamarind.
For a menu, rather than a strong fried rice such as nasi goreng (in Japanese), it eats lighter with cucumber, tomato and boiled greens alongside. If you pair it with something rich, a brothy soto ayam lets off the heaviness of the table better than a meat-forward rendang (in Japanese).
Frequently Asked Questions
Can I use potato starch instead of tapioca starch?
You can make it set, but the texture changes. With potato starch alone it tends to get gritty when cool and moves away from pempek's chewy bite. If you must use it, replace only 50 g of the tapioca starch with potato starch.
Is frozen surimi all right for the fish?
Yes. Salt and moisture differ by product, so reduce the salt a little and press out the water before use. If the surimi is soft, don't add all the ice water at the start; add it while watching for a firmness you can shape.
Can I skip the egg-filled ones and make everything long?
No problem. Lenjer alone is more likely to succeed the first time. Boil them long and cool, then cut and fry just before eating, and the cuko clings to the cut face. Add the egg-filled ones once you are used to it.
Can I make the cuko without heat?
Yes. Leave out the red chili and make it with garlic, palm sugar, tamarind, rice vinegar and salt. Without chili the sweet-sourness comes forward, so adding just 1 tsp rice vinegar tightens the flavor. Letting those who like heat add chili at the table makes it easy for the whole family.
Can I eat it boiled, without frying?
Yes. There is a way of eating it boiled locally too. At home, though, a short fry gives fragrance and goes better with the acidity of the cuko. On days you want to avoid oil, put 1 tbsp oil in a pan and roll the pieces over medium heat to color them.
More Indonesian Dishes to Cook Together
Pempek is a dish of fish and sourness, so it is easier to eat with lighter plates from Indonesian cooking. On a day you made extra cuko, it can go to a side dish the next day.
- Papeda (in Japanese): compare the sago and tapioca starch culture as a staple of eastern Indonesia.
- Siomay (in Japanese): compare another dish using fish and tapioca starch, steamed dumplings with peanut sauce.
- Sate Padang (in Japanese): also from Sumatra, but fish and acidity in pempek against beef and a yellow sauce in the sate.
- Gado-gado: a plate of boiled vegetables on the side lets off the heaviness of fried pempek.
- Sambal substitute: a small dish when you want to add heat at the table.
Sources: Overseas and Local Information
The Indonesia Travel introduction to pempek was consulted to confirm its Palembang origin, the fish, tapioca starch and cuko ingredients, and the relationship with the fish resources of the Musi River. The Journal of Ethnic Foods paper was used as a basic source for confirming that pempek is tied to Palembang's history, geography and ethnic identity, and for the place of fish, sago, palm sugar and cuko. Tasty Indonesian Food and What To Cook Today were consulted to cross-check the dough, boiling, frying and cuko steps for home cooking.
