How to choose and store elephant foot yam (chena)

By the Cochimart Kitchen Desk · Published 30 October 2026

Chena: the short answer

A good chena (ചേന), the elephant foot yam, is a heavy, firm corm with intact skin and no soft or wet patches. Keep a whole corm unwashed in a cool, shaded, well-ventilated place, and use it before it starts to sprout or shrivel. Once it is cut, wrap the pieces, refrigerate them and use them within a few days. Wear gloves when you peel it: the raw corm can make skin and mouth itch.

Chena sits on our vegetable names list beside its relatives chembu and kachil, and it is one of the produce items that shows up strongly on the Kerala season calendar in the cooler months.

What chena actually is

Elephant foot yam is the underground storage organ, a corm, of Amorphophallus paeoniifolius, a tropical plant in the arum family. Wikipedia says the corm can reach about 30 cm across and weigh up to 15 kg, so stalls often sell it as wedges cut from a bigger piece. It is also known as suran or jimmikand in other parts of India, and Wikipedia notes that in Kerala the corm has been part of the diet for centuries.

It is easy to mix up with other starchy tubers, so here is how the names line up.

Malayalam Wikipedia lists the main varieties as Sree Padma, Gajendra and Kuzhimundan, the last a type associated with Peermade. You rarely see variety names at a city stall, so judge each corm on how it looks and feels rather than on a label.

Why chena is a cool-weather vegetable in Kerala

The Kerala crop calendar explains the season. Scientists at ICAR-CTCRI, the central tuber crops institute in Thiruvananthapuram, write that in Kerala elephant foot yam is planted in February and harvested in November and December under rain-fed conditions. The ICAR-CCARI crop note says the crop is ready roughly eight to nine months after planting, once the leaf and stalk have withered, although growers may dig earlier if the market suits them.

That fits the pattern in our season calendar, which marks chena from November to February. It is worth knowing for two reasons. First, corms dug in the season are usually the freshest you can find. Second, the CCARI note says corms harvested in November are stored in well-ventilated rooms until planting time, a reminder that a sound chena really does keep well when it is stored dry and airy.

Why chena itches

This is the most useful thing to know about chena before you buy it. Wikipedia explains that the corm contains raphides, needle-like calcium oxalate crystals, and the Philippines tradition of cooking it thoroughly is aimed at destroying those stinging crystals. The ICAR-CCARI crop note says tubers and leaves are quite acrid because of their high oxalate content, and that the acridity is usually removed by boiling for a fairly long time. Malayalam Wikipedia also says that a high calcium oxalate content is what produces the itching.

The CTCRI review adds one detail: it cites research that corms are more acrid before they pass through dormancy, and less so afterwards. We would not rely on that to judge a corm at the stall, but it is a good reason never to handle or taste a raw corm casually.

• Wear kitchen gloves, or rub a little oil on your hands, when you peel and cut it.
• Rinse your hands and the knife well afterwards, and keep your hands away from your eyes and mouth.
• Do not taste raw chena. It must be cooked thoroughly before eating.

If your skin does itch, rinsing with plenty of water is the sensible first step. Anything more than mild irritation is a question for a doctor, not for a food guide.

Choosing chena at the stall

• Pick it up. A good corm feels heavy for its size and hard throughout. A light corm may have lost water, and a spongy one has begun to rot.
• Look at the skin. It should be dry, rough and unbroken. FAO stresses for roots and tubers in general that skin is the barrier against decay, and that cuts and bruises let disease in.
• Ask to see a cut face. Stalls often cut a large corm into wedges. The cut surface should be firm and even, without dark, slimy, sunken or watery areas or a sour smell.
• Check the top. The crown, where the stalk grew, should be dry. Wet, soft or fuzzy patches there mean trouble.
• Skip very shrivelled or heavily sprouted corms. Long shoots and wrinkled skin mean it is old.
• Prefer a fresh cut. A wedge that was cut hours ago and has a dry, dull face may already be deteriorating, so choose a freshly cut piece or a small whole corm.

Add chena to the bilingual grocery list in both English and Malayalam so the stall owner knows exactly which corm you mean, since many vegetables there are starchy and rough-skinned.

How to store chena at home

Whole, uncut corm

1. Brush off loose soil. Do not wash the corm before storing it, and make sure any damp patches are completely dry.
2. Place it on a rack, a basket or a layer of newspaper in a cool, shaded, well-ventilated spot: a store room, a ventilated cupboard or a shaded verandah corner. Avoid sealed plastic bags.
3. Keep it away from the stove, direct sun and damp floors. FAO explains that tubers are living things which give off heat and carbon dioxide, and that natural ventilation is what carries both away.
4. Handle it gently. FAO notes that damage speeds up respiration and opens the way for decay.
5. Check it every few days and use it before it sprouts or softens.

A sound whole corm will usually last a few weeks in a cool, airy store room. That is our practical estimate, not a measured figure, because house temperatures in Kerala and the Gulf vary so much.

Cut pieces

Once a corm is cut, the exposed face dries out and invites rot. If you bought a wedge, or only needed part of a large corm, wrap the cut side in a clean cloth or paper, put the piece in a container in the fridge, and use it within a few days. Peeled and cut chena should be treated as a perishable food. Anything cooked belongs in a covered container in the fridge and should be eaten within a day or two.

Why not keep the whole corm in the fridge?

FAO's handbook gives chilling thresholds for true yams, which belong to a different genus, and says damage depends on both temperature and time. It does not give a figure for elephant foot yam itself, so we are cautious: tropical tubers generally do better in a cool, dry room than in a cold, damp fridge. Use the fridge only for cut or cooked pieces.

When to throw chena out

• Soft, mushy, leaking or slimy corm, or sunken dark patches.
• Mould, especially white or grey fuzz on the crown or cut face.
• A sour, fermented or musty smell, on the skin or when cut.
• Flesh that is dark or watery through much of the piece rather than in one small spot.

A small bruise can be cut away generously. If rot has spread, discard the piece. Because chena is bulky, it is tempting to keep a doubtful wedge, but a safe food is worth more than the corm.

For more everyday produce, see our guides to drumsticks and ginger, or browse all the ingredient guides.

Sources and useful links

• ICAR-CTCRI scientists, Crop physiology of elephant foot yam (Amorphophallus paeoniifolius), Advances in Horticultural Science
• ICAR-CCARI, Crop: Elephant foot yam
• FAO, Storage and processing of roots and tubers in the tropics, Chapter 2: Factors affecting storability of roots and tubers
• Wikipedia: Amorphophallus paeoniifolius
• Malayalam Wikipedia: ചേന (chena)

Frequently asked questions