Traditional Fermented and Preserved Fish Products

TRADITIONAL FERMENTED AND PRESERVED FISH PRODUCTS

Ngari · Hentak · Tungtap · Gnuchi

 

The Eastern Himalayan area - eastern Nepal, Bhutan, Darjeeling, Sikkim, and the North-Eastern Indian states of Assam, Arunachal Pradesh, Meghalaya, Tripura, Mizoram, and Manipur - have historically lacked access to refrigeration. Freshwater fish caught from rivers, streams, and lakes are highly perishable, so indigenous communities in these areas developed low-cost biopreservation methods using natural ingredients (salt, turmeric, smoke).

Four Broad Categories of Traditional Fish Products

Category	Examples	Basic Principle
Smoked & sun-dried	Gnuchi, Suka ko maacha	Salt/turmeric cure + slow smoke-drying above a hearth
Sun-dried / salted (non-fermented)	Sidra, Sukuti, Karati, Bordia, Lashim	Washing, salting, and open sun-drying only
Fermented (paste/whole)	Ngari, Hentak, Tungtap, Shidal	Anaerobic packing in sealed earthen pots; microbial fermentation

 

Microbes involved in fish fermentation

• Lactic Acid Bacteria (LAB): Lactococcus lactis (subsp. lactis & cremoris), Lactobacillus plantarum, Leuconostoc mesenteroides, Enterococcus faecium, E. faecalis, Pediococcus pentosaceus, Weissella confusa.

• Spore-formers / Micrococci: Bacillus subtilis, Bacillus pumilus, Micrococcus spp.

• Yeasts: Candida spp. (C. chiropterorum, C. bombicola), Saccharomycopsis spp.

• Halophiles/others (in deep-fermented pastes such as ngari): Staphylococcus cohnii, Staphylococcus carnosus, Tetragenococcus halophilus.

These organisms carry out proteolysis, acid production, and flavour/aroma development, while simultaneously suppressing spoilage and pathogenic organisms.

 

 

1. Ngari

A non-salted, long-fermented whole-fish product which is the signature flavour base of Meitei cuisine (Meitei community).  These are eaten daily as a side dish with cooked rice and are a key flavouring base for Eromba and Singju, which are traditional Manipuri dishes.  Sold in local markets, typically packed inside earthen pots.

 

Prepared by Anaerobic solid-state fermentation of whole fish, Puntius sophore (this is a small freshwater fish, locally known as Phabou nga)

1. Fish are rubbed with salt and sun-dried for 3–4 days.

2. Dried fish are washed briefly and spread out on bamboo mats.

3. The inner wall of an earthen pot is coated with a layer of mustard oil (to seal pores and aid anaerobic sealing).

4. The pot is filled with the dried fish, which is then pressed down tightly by foot to remove air pockets.

5. The pot is sealed airtight and stored at room temperature for 4–6 months (can be kept for over a year).

Characteristics include Soft texture with a strong, pungent, distinctive aroma, light brown to golden-brown colour, and whole fish remain visually intact but softened by fermentation.

Microflora involved

Bacteria: Lactococcus lactis subsp. cremoris, Lactobacillus plantarum, Enterococcus faecium, L. fructosus, L. amylophilus, L. coryniformis subsp. torquens, Bacillus subtilis, B. pumilus, Micrococcus sp.

Yeasts: Candida spp., Saccharomycopsis spp.

 

 

2. Hentak

This is a fermented fish-and-plant paste with therapeutic/nutritional value used in Manipur, consumed as a curry ingredient and used as a condiment, and traditionally given to women in the final stages of pregnancy or to patients recovering from sickness/injury.

 (Image Credit: The Manipuri Foodie @facebook)

Prepared by Solid-state paste fermentation of fish, Esomus danricus (finger-sized freshwater fish) and petioles of Alocasia macrorhiza (giant taro)

1. Finger-sized fish are washed thoroughly, sun-dried, and crushed into a fine powder.

2. Petioles of Alocasia macrorhiza are cut into pieces, washed, and exposed to sunlight for 1 day.

3. An equal amount (roughly 1:1) of cut petiole pieces is mixed with the powdered fish.

4. The mixture is made into a ball-like thick paste.

5. The paste balls are kept in an earthen pot, sealed tightly, and fermented at room temperature for 7–9 days.

Characteristics of Hentak are paste-like consistency with a strongly pungent aroma and are ball-shaped when freshly prepared.

Microflora involved

Bacteria: Lactococcus lactis subsp. cremoris, Lactobacillus plantarum, Enterococcus faecium, Lactobacillus fructosus, Lactobacillus amylophilus, Lactobacillus coryniformis subsp. torquens, Bacillus subtilis, Bacillus pumilus, Micrococcus sp.

Yeasts: Candida spp., Saccharomycopsis spp.

3. Tungtap

This is a salted, short-fermented fish paste used in Meghalaya by the people of the Khasi Hills. Consumed as a pickle and used in curries and often ground/mixed with chillies and other spices before serving as a side condiment.

 

Prepared by salted fermentation of whole fish, Danio spp. (small freshwater fish)

1. Sun-dried fish are washed briefly and mixed thoroughly with salt.

2. The salted fish are packed into an earthen pot, which is sealed airtight.

3. The pot is left to ferment at room temperature for 4–7 days.

Characteristics of Tungtap: a semi-solid paste with a sharp, salty-fermented aroma.

Microflora involved

Bacteria: Lactococcus lactis subsp. cremoris, Lactobacillus plantarum, Enterococcus faecium, L. fructosus, L. amylophilus, L. coryniformis subsp. torquens, Lactobacillus puhozihii (identified specifically from tungtap and shown to have bacteriocinogenic potential), Bacillus subtilis, B. pumilus, Micrococcus sp.

Yeasts: Candida spp., Saccharomycopsis spp.

4.   Gnuchi

This is a smoked and dried (not fermented) fish product of the Lepcha community of Sikkim & Darjeeling hills.  They cook this into traditional fish curries and soups

Prepared by Smoking and slow drying of fish, Schizothorax richardsonii, Labeo dero, Acrossocheilus spp., Channa sp. (riverine species)

1. Fish are collected from river and kept on a large bamboo tray to drain off water.

2. Fish are degutted, then mixed with salt and turmeric powder, and separated according to size.

3. Bigger fish are spread in an upside-down manner on a bamboo rack called sarhang, positioned above the earthen kitchen oven.

4. Smaller fish are hung one after another on a bamboo strip above the same oven.

5. Fish are smoked continuously above the earthen oven for 10–14 days.

6. The finished gnuchi is kept at room temperature for 2–3 months and eaten as curry.

Characteristics of Gnuchi - Firm, chewy texture with a smoky aroma.

Microflora Identified

Bacteria: Lactococcus lactis subsp. cremoris, L. lactis subsp. lactis, Lactobacillus plantarum, Leuconostoc mesenteroides, Enterococcus faecium, Enterococcus faecalis, Pediococcus pentosaceus.

Yeasts: Candida chiropterorum, Candida bombicola, Saccharomycopsis spp.

 

Feature	Ngari	Hentak	Tungtap	Gnuchi
Region and Community	Manipur Meitei	Manipur	Meghalaya Khasi	Sikkim/Darjeeling Lepcha
Fish used	Puntius sophore	Esomus danricus	Danio spp.	Schizothorax spp., Labeo dero
Plant additive	None	Alocasia macrorhiza petioles	None	None (salt + turmeric)
Process type	Anaerobic pot fermentation (whole fish)	Paste fermentation (powder + petiole)	Salted pot fermentation (whole fish)	Smoking + sun/hearth drying
Duration	4–6 months	7–9 days	4–7 days	10–14 days smoking
Physical form	Whole soft fermented fish	Moist ball-like paste	Semi-solid paste	Firm smoked whole/degutted fish
Special uses	Daily staple, Eromba, Singju	Given to pregnant women/convalescents	Pickle/curry base	Curry, soup

 

Biochemical Changes

• Proteolysis and flavour development - During fermentation, endogenous fish enzymes (cathepsins, calpains) and microbial proteases from Lactobacillus and Bacillus species break down muscle proteins into peptides and free amino acids (e.g., glutamic acid, lysine, glycine). This is the main source of the characteristic umami taste and strong aroma of ngari, hentak, and tungtap.

• Mechanisms of bio preservation –

1. Lactic acid accumulation: LAB ferment residual carbohydrates into lactic and acetic acid, lowering pH and inhibiting spoilage/pathogenic organisms.

2. Salting & drying: Reduces water activity (aw), suppressing growth of pathogens.

3. Anaerobic packing: Tight compaction in sealed earthen pots (ngari, hentak, tungtap) creates an oxygen-free environment that favours facultative/obligate anaerobic LAB over aerobic spoilage flora.

4. Bacteriocin production: Certain isolated strains (e.g., Lactobacillus puhozihii from tungtap) produce antimicrobial peptides that further suppress competing and pathogenic bacteria.

5. Smoking (gnuchi): Deposits antimicrobial phenolic compounds and reduces surface moisture, extending shelf-life without a sealed anaerobic fermentation step.

 

References

Thapa, N. (2016). Ethnic fermented and preserved fish products of India and Nepal. Journal of Ethnic Foods, 3(2), 69–77.