1. Fermentation is a popular preservation technique for fish in Southeast Asia that involves the action of enzymes and microorganisms to transform organic substances into simpler compounds. 2. There are three main types of raw materials used - small bony fish, oily short-lived fish, and fast-growing fish with little demand for human consumption. Quality, availability, price, processing, and cost/profitability must also be considered. 3. Popular fermented fish products include fish sauce produced by fermenting fish and salt, fish paste made by reducing fish to a paste form, and dried bonito produced through alkali fermentation without salt. Each product involves different fermentation processes and results in distinct final forms

1. Semi-fermented and
Fermented Products

2. Introduction
• Fermentation is a popular technology for the preservation of fish in
Southeast Asian countries
• Transformation of organic substances into simpler compound by the
action of enzymes and microorganisms
• All types and even marginally spoiled materials can be used
• Fermentation technology is popular during bulk harvest of fish
• It can also equally be applied to underutilized species or industrial
species

3. Suitability of Raw Materials
In general, three types of raw materials are used in fish
meal manufacture which includes-
Mainly small bony fish,
Oily short-lived,
Fast-growing fish where there is little or no demand for human
consumption.
Quality
Availability
Price
Processing
Cost and Profitability

4. Fermented fish ingredients and their respective product example (Source:
Chan et al., 2023)

5. Principles of Fermentation
Chemical and
biochemical
reactions (Ray &
Joshi, 2014)
Endogenous
proteolytic and
lipolytic enzymes
helped to ferment
fish (Zang et al.,
2020)
Lactic Acid Bacteria
(LAB)
Undergo autolysis
or self-digestion
and resulting in a
liquid fish ferment
(Anihouvi, 2012)
The primary role of
lactic acid bacteria
is to ferment
available
carbohydrates (Doe
et al., 2017)
Various types of
salts are used for
the salting and
fermentation of fish
The addition of salt
and many additives
reduces the water
activity and
protects the
product from
spoilage
microorganisms
Factors:
Concentration of
microorganisms,
cells, cellular
components, and
enzymes as well as
temperature, pH
(Doe et al., 2017)

6. Process of Fermentation of Fish (Source: Chan et al., 2023)

7. Types of Fermented Fishery Products
Products primarily involving enzymatic hydrolysis.
Products preserved by microbial fermentation.
Different fermentation processes result in 3 distinct types of products-
a) Fish largely
retains original
form: cured texture
and aroma, as in
shidhal of
Bangladesh
b) Original fish
reduced to the
form of paste:
red/brown, salty,
as in Nga-pi of
Bangladesh
c) Flesh is
reduced to a
liquid: salty
taste, cheese
like aroma, as
in fish sauce

8. Fermented fish products can be divided based
on salt concentration-
• High salt > 20%
Liquid separation - Fish sauce
Residue or no separation - Cured fish
Comminution or fish paste - Partial drying
• Low salt
Salt (6-20%) - Lactic acid fermentation, acid pickling etc
Salt <6% - Shidhal, Nga-pi
• No salt
Dried bonito fermentation
Alkali fermentation

9. Fish sauce Fish paste Dried bonito Shidhal

10. Techniques of Fermentation
Fish Sauce Shidhal Shutki
Fermentation: Transformation of organic
substances into simpler compound.
Example- Fish Sauce, Fish Paste, Fish Pickle
Semi Fermentation: Process of partial
breakdown of protein molecule.
Example- Shidhal Shutki

11. Changes in
Constituents
During Fish
Fermentation
The development of a specific aroma
Soft and tender fish texture
Formation of inosine, hypoxanthine, ribose etc.
Trimethyl amine oxide (TMAO) to Trimethyl amine (TMA)
Formation of diethyl amine (DMA)
Breakdown of protein
Oxidative rancidity in of the fish
Strong odor in spoilt fish
According to Asiedu, & Sanni,
(2002), Riebroy et al., (2007) and
Xu et al., (2021) following
changes occurred during fish
fermentation they are-
Volatile bases particularly TMA, DMA and NH3 are associated with
changes in the organoleptic and textural quality of fish

12. Insights on the Processing and Safety of Fermented Fish and the Associated Changes
(Source: Chan et al., 2023

13. 1. Fish Pickle
Pickle is also called achar
It is a sacred food item made with lot of love and
affection
Can make boring meals into something extraordinary
Suitable fish species:
Low value fish such as thread fin bream, mackerel,
perches etc. are ideal raw materials for the preparation of
fish pickles.

14. Preparation
Procedure
of Fish
Pickle
Fish cut into small pieces and addition of salt
(Fish: Salt = 1:1)
Mixture kept for 2-3 hours
Garlic, ginger, green chillies are gently fried in
oil
Addition of fish mixer
Turmeric and chilli powder are added into it
Sufficient amount of boiled cooled water is
added
Packed in airtight glass bottles
Aging for 2-3 months
Fish pickle

15. Preparation of Fish Pickle

16. 2. Shidal Shutki
Salt-free fermented fish product
Very much popular due to its strong flavour
Locally called shidal, sepaa and hidal.
Suitable Fish Species:
For the production of Shidal Sutki, Puntius spp.
are used mostly, and winter season is mostly
favoured for the production of Shidal Sutki
throughout the country.

17. Raw materials (dry Puntius sp.)
Preparation
Procedure of
Shidal Shutki
Sorting by hands and sun drying
Water soaking/washing preferably in running water
Overnight drying at room temp. by spreading on bamboo
mat
Filling the partially dried fish in oil smeared fermenting
containers (matka) upto neck portion with strong
compaction
Sealing of mouth portion with cover paste made from dry
fish
Wrapping of cover paste with paper or banana leaves and
keep undisturbed for 3-4 days
Replace of cover leat/paper with a thick layer of
clay
Fermentation is allowed for 3-5 months at ambient
temp
Final product (shidal) is taken out after carefully
removing of clay seal and cover paste

18. Raw Materials and Final Product Of Shidal Shutki

19. 3. Nga-pi
Collection of Raw
Materials
Cleaning
Sun Drying (for 1
day)
Sun drying (for 1day)
Threshing by feet
Threshing for 6 times in wooden
mortar (with 2-2.5% salt)
Shaping
Wrap with mos leaves
Packing in split bamboo basket
Threshing by feet
Store
Threshing for 6 times in wooden
mortar
Scheme for The Preparation of Nga-pi

20. 4. Fish Sauce
Scheme for The Preparation of Fish Sauce
Fish + Salt (6:4)
Mixing
Fermentation
Agitation
Fish Sauce
Cured fish
Residue for 2nd
harvest
Filtration

21. The Health Benefits of Fermented Fish Products (Source: Chan et al., 2023)

22. Conclusion
Fermented fish products play a crucial role in various cultures and cuisines
worldwide. They offer unique flavors, enhanced nutritional value, and
preservation benefits. The appreciation and utilization of these products
contribute to culinary diversity and the promotion of sustainable food
practices.

23. References
Anihouvi, V. B., Kindossi, J. M., & Hounhouigan, J. D. (2012). Processing and quality characteristics of some
major fermented fish products from Africa: a critical review. International Research Journal of Biological
Sciences, 1(7), 72-84.
Asiedu, M., & Sanni, A. I. (2002). Chemical composition and microbiological changes during spontaneous and
starter culture fermentation of enam ne–setaakye, a West African fermented fish-carbohydrate product.
European Food Research and Technology, 215, 8- 12.
Chan, S. X. Y., Fitri, N., Mio Asni, N. S., Sayuti, N. H., Azlan, U. K., Qadi, W. S., ... & Mediani, A. (2023). A
Comprehensive Review with Future Insights on the Processing and Safety of Fermented Fish and the
Associated Changes. Foods, 12(3), 558.
Doe, P., Sikorski, Z., Haard, N., Olley, J., & Pan, B. S. (2017). Basic principles. In Fish Drying & Smoking (pp.
13-45). Routledge.
Ray, R. C., & Joshi, V. K. (2014). Fermented foods: past, present and future. Microorganisms and
fermentation of traditional foods, 1-36.
Riebroy, S., Benjakul, S., Visessanguan, W., & Tanaka, M. (2007). Changes during fermentation and properties
of som‐fug produced from different marine fish. Journal of Food Processing and Preservation, 31(6), 751-
770.
Xu, Y., Zang, J., Regenstein, J. M., & Xia, W. (2021). Technological roles of microorganisms in fish
fermentation: a review. Critical Reviews in Food Science and Nutrition, 61(6), 1000- 1012.
Zang, J., Xu, Y., Xia, W., & Regenstein, J. M. (2020). Quality, functionality, and microbiology of fermented
fish: a review. Critical Reviews in Food Science and Nutrition, 60(7), 1228- 1242.

24. Thank You