Gundruk, Sinki and Nepali Fermented Foods: A Complete Guide

Fermented and preserved foods sit at the heart of the Nepali kitchen, especially in the hills and mountains where fresh vegetables disappear for months during the long, cold, dry season. By harnessing naturally occurring bacteria, yeasts and moulds, households turn a short autumn glut of greens, roots, soybeans or milk into stable, tangy, nutrient-dense staples that keep for months or even years without refrigeration. These foods are cheap food-security insurance, a way of avoiding waste, and a source of the sour, umami-rich flavours that define everyday Nepali eating.

The most researched of these is gundruk, a salt-free fermented and dried leafy vegetable widely regarded as a Nepali national-identity food. Alongside it sit sinki (fermented radish tap root), masyaura (fermented legume-and-vegetable nuggets), kinema (sticky fermented soybean of the eastern Kirat communities), and the dairy ferments dahi (curd) and its royal Bhaktapur form juju dhau, plus clarified butter (ghee/ghiu). Nepal's fermented foods have been documented most systematically by Tribhuvan University and by microbiologist Professor Jyoti Prakash Tamang, whose work on Himalayan ethnic fermented foods remains the standard scientific reference. Government oversight comes from the Department of Food Technology and Quality Control (DFTQC) under the Ministry of Agriculture and Livestock Development, which in 2081 BS (2024/25) began setting formal quality standards for products such as gundruk.

Gundruk is made from the leaves and stems of Brassica (mustard-family) vegetables. Rayo (broad-leaf mustard), rapeseed, radish and cauliflower leaves are the classic raw materials, harvested in October and November (Kartik-Mangsir) when the season produces far more greens than a family can eat fresh. Crucially, no salt is added; gundruk is a spontaneous lactic-acid fermentation driven by bacteria naturally present on the leaves.

The leaves are first wilted in the sun for one to two days until they soften, then shredded. The shreds are packed very tightly into an earthenware pot (traditionally a ghyampo), and warm water at about 30 degrees Celsius is poured in to submerge the mass completely and exclude air. The pot is kept in a warm place. Over roughly a week, lactic-acid bacteria, chiefly Pediococcus and Lactobacillus species, ferment the greens: the pH drops slowly to about 4.0 and lactic acid rises to around one percent by the sixth day, producing the characteristic mild-sour smell and taste.

When fermentation is complete, the sour greens are removed and spread out to dry thoroughly in the sun. Well-dried gundruk keeps for months to years at room temperature. It is later rehydrated for gundruk ko jhol (a tangy soup), fried as a side (gundruk sadeko or bhutuwa), or added to dal and curries. One well-documented nutritional drawback is that sun-drying destroys roughly 90 percent of the carotenoids (provitamin A) in the leaves, so gundruk is prized more for its acids, minerals and flavour than for vitamin A.

Sinki is gundruk's underground cousin: a non-salted, lactic-acid fermented product made from radish tap roots rather than leaves. Fresh radish roots are washed, sun-wilted for one to two days until soft, shredded, and rammed tightly with a wooden pestle into an earthen jar (or, traditionally, a straw- and bamboo-lined pit sealed with vegetation, wood and mud). Fermentation runs long, roughly 20 to 40 days, driven by lactic-acid bacteria such as Lactiplantibacillus plantarum, Levilactobacillus brevis and Leuconostoc species. The pH falls to about 3.3-3.8, low enough that the sun-dried product stores safely for around a year at room temperature without refrigeration. Sinki is mainly used as a sour soup base and pickle.

Masyaura (also spelled maseura or masaura) is a fermented and dried nugget made by combining ground black gram (maas dal) with minced vegetables, most traditionally taro corm, taro stems and taro leaves (karkalo/gaava), and sometimes ash gourd or other vegetables. The paste is mixed until sticky, hand-shaped into small nuggets, and dried in the sun over several days while a light fermentation develops. The dried nuggets are shelf-stable for months and are fried and cooked into curries, adding protein and a savoury, spongy texture.

Both sinki and masyaura are household staples that, like gundruk, convert a seasonal surplus into a durable pantry food, and remain popular today, including among the Nepali diaspora who carry them abroad.

Kinema is a sticky, strong-smelling fermented soybean food of the Kirat communities, chiefly the Limbu and Rai, of the eastern hills of Nepal (historic Limbuwan) and adjoining Sikkim and Darjeeling in India. The name comes from the Limbu language, where 'ki' relates to fermentation and 'nambaa' to flavour. Unlike the salt- and acid-based vegetable ferments, kinema is an alkaline Bacillus fermentation, and is often compared to Japanese natto.

To make kinema, dried soybeans are soaked overnight, boiled until soft, drained and lightly pounded or cracked. The warm beans are packed into a bamboo basket lined with fern fronds and banana or fig leaves, sometimes with a little firewood ash added to raise alkalinity, and left in a warm spot near the kitchen fire for about one to two days. Bacillus subtilis dominates the mixed-culture fermentation, breaking down soy protein and producing the sticky threads and glutamic acid responsible for kinema's umami, meaty flavour and ammoniacal aroma. Fresh kinema is cooked quickly into a curry; surplus is sun-dried for storage.

Kinema is nutritionally notable as a protein-rich, plant-based food carrying beneficial Bacillus and other microbes, and it is a marker of Kirat cultural identity. Scientific interest has grown around its bioactive compounds and health-associated properties, though researchers also warn that the traditional know-how is eroding as younger generations move away from home production.

Nepal's fermented dairy foods start with dahi, curd made by inoculating warm milk with a small amount of previous curd and letting lactic-acid bacteria set it. Dahi is eaten daily, churned into mohi (buttermilk), and is essential to festivals such as the dahi-chiura (curd and beaten rice) eaten on Gai Jatra and other occasions. The best-known regional form is juju dhau, literally 'king of curds' in Nepal Bhasa, a specialty of Bhaktapur associated with the Newar community and the Malla era.

Juju dhau is made from rich buffalo milk, which is boiled and reduced with sugar and sometimes spices, then poured warm into unglazed clay pots and inoculated with a starter culture. The porous clay absorbs excess moisture as the curd ferments, giving juju dhau its dense, custard-like set and creamy, caramel-tinged flavour. It is the classic sweet finish to a Newar feast (bhoj) and a signature of Bhaktapur's food culture.

Ghee (ghiu), clarified butter, is a related dairy product made by simmering butter churned from cultured cream or curd until the water evaporates and milk solids separate, leaving a golden, nutty fat. Because it is essentially free of water and milk solids, ghee is extremely shelf-stable at room temperature, and it carries deep ritual importance in Hindu worship (as lamp fuel and offering) as well as being a prized cooking and finishing fat.

The shared advantage of Nepal's ferments is preservation without a cold chain. Lactic-acid fermentation drops the pH of gundruk to around 4.0 and of sinki to roughly 3.3-3.8, creating an acidic, low-oxygen environment hostile to spoilage and pathogenic microbes; sun-drying then removes the water that microbes need, so dried gundruk and sinki keep for months to about a year at room temperature. Ghee's near-zero water content and kinema's drying give them similarly long, ambient shelf lives.

Nutritionally, these foods concentrate minerals and acids and add live or resident beneficial microbes and their metabolites to the diet, which is why gundruk, sinki and kinema are increasingly studied for gut-health and probiotic-associated properties. Kinema and masyaura add valuable plant protein; dahi and juju dhau supply protein, calcium and live cultures. The main caveat is vitamin loss: traditional sun-drying destroys about 90 percent of the carotenoids in gundruk, so these are flavour-and-mineral foods rather than reliable vitamin-A sources.

Food safety depends on hygiene and the right vessels. Nepal's gundruk standard bans reactive metal containers (iron, aluminium, copper, brass) because acids can leach metals, and prohibits artificial colours and fragrances. Well-made ferments are safe and self-preserving; poorly dried or contaminated batches can develop mould, off-odours or spoilage, which is exactly what the new national standards aim to prevent.

For most of its history gundruk was an unregulated household product with no legal definition. That changed in 2081 BS (2024/25), when the Government of Nepal, through the Ministry of Agriculture and Livestock Development, set formal quality standards for gundruk for the first time, exercising authority under the Food Hygiene and Quality Act, 2081 (2024). Gundruk is classified among fruit and vegetable products and legally defined as a fresh or dried product made by wilting and naturally (or pure-culture) lactic-acid fermenting mustard, rapeseed or radish greens without salt.

The standard sets measurable limits for dried gundruk: a maximum of 12 percent moisture, maximum 17 percent total ash, maximum 1 percent acid-insoluble ash, and a minimum acidity of 0.8 percent. It requires the product to be clean and free of mould, insects and foreign matter, bans artificial colours and fragrances, prohibits iron, aluminium, copper and brass production vessels, and mandates food-grade packaging. Enforcement falls under the DFTQC framework.

A common point of confusion is Geographical Indication (GI) status. Despite frequent media calls to protect gundruk and other products with GI tags, Nepal has historically lacked a functioning GI registration regime; commentators and researchers note that the country had no formally registered GI products, and comprehensive GI legislation (folded into a draft Industrial Property Bill) has been pending rather than enacted. In short, the 2081 quality standard is a food-safety and quality measure, not a GI registration. Readers should treat any specific claim that gundruk has been granted a GI as unverified until Nepal's GI system is operational and an official register confirms it.