This document discusses various by-products that can be obtained from fish processing. It describes how fish unsuitable for human consumption and fish parts are used to produce items like fish oil, fish meal, fish manure, hydrolyzed protein, isinglass and other products. The document provides details on the production processes and uses of these different by-products. It explains that utilizing fish in this way helps reduce waste and generates additional economic benefits from the fishing industry.

1. GOVT. P.G COLLEGE
JHALAWAR
SEMINAR ON
FISH BY-PRODUCTS
SUBMITTED TO :- FROM :-
MISS - ARZOOMAND QRESHI MANISH KUMAR SAINI
MRS – ROOPAM KULSHRESTHA M.SC (FINAL)ZOOLOGY

2. FISH BY-PRODUCTS
CONTENTS
INTRODUCTION
 Categories of fish oil
 Fish meal
 Fish manure
 Hydrolysed protein from waste fish
 Other fish by-products

3. INTRODUCTION
 Fish unsuitable for human consumption is often discarded during
processing. These and such species which have little market value
from important raw material for a fishery by-product industry .
 Fish is a highly perishable food material because of its moisture and
nutrient contents, and spoilable begins as soon as fish dies, it is the
result of a series of complicated chemical reactions taking place in
a dead fish, mainly by enzymes and bacteria.
 These are either thrown back into the sea immediately after their
catch or utilized wholly or partly as manure .

4. CATEGORES OF FISH OIL
1. Fish liver oil
2. Fish body oil
Pale cod liver oil
Light brown oil
Brown oil

5. 1. FISH LIVER OIL
 Fish liver oil is obtained from fish liver.
 Soon after the fish is dead, the enzymes present in the liver start their
action on the proteinaceous matter and fats are broken down into
fatty acids and glycerine.
 The oil becomes darker in colour due to oxidation. Therefore, in
order to obtain good quality oil, the processing of liver must be
done soon after the fish is caught. Oil is extracted from liver of dead
fish.

6. FISH LIVER OIL
 METHOD :-
 Liver is chopped into small pieces and boiled with sufficient water.
The oil is skimmed off from the surface of water.
 COMPOSITION OF FISH LIVER OIL :-
 FAT 55.75%
 PROTEIN 5-10%
 WATER 20-36%
 VITAMIN A & D

7. FISH LIVER OIL
PALE COD LIVER OIL :-
 It is yellow in colour.
 It is obtain from cod fish and fishes found costal region of sea.
 It has highest medicinal value it contains vit.-D and vit.-E.
LIGHT BROWN OIL :-
 It is light brown in colour. It is obtain frim disintegrated liver.
BROWN OIL :-
 It is brown in colour. It is not use in pharmacy.

8. FISH LIVER OIL use of fish liver oil
 The medicinal value of fish liver oil was known even in old times.
 It is remarkable that the two important vitamins, A and D essential
for man , occur in liver oil in the required quantity , enhancing its
medical value.
 Cod liver oil was known to cure both ‘rickets’ and ‘exophthalmia’.
 The fish oil is helpful in the growth of teeth and bones .
 It increase the immunity of human body and maintenance of
human skin.

9. FISH BODY OIL
 This oil is different from fish liver oil. Oil extracted from the whole
body of fish or fish fat.
 Fresh fish or those preserved in salt are boiled in water oil remove.
 The boiled flesh is pressed to obtain dark yellow oil which contains
impurities and has bad odour.
 In large factories a copper pan is generally preferred and fish are
constantly boiling and give oil.

10. FISH BODY OIL
 The body oil are used in the manufacture of soaps. It used to
manufacture candles.
 Fish body oil also use for oiling the bottom of the boats to protect
them against sea-rot.
 It is also used in the manufacture of paints and varnishes that more
resistant to heat.
 A good quality oil is clear pale yellow to brown in colour , while dark
coloured oil is of inferior quality.

11. FISH MEAL
 Fish meal is clean cooked , dried tissue of undecomposed fish. It is
produced in Chennai, Maharashtra, Orissa and west Bengal coast.
Species that form the raw material are sardines, mackerels, ribbon
fish , sliver belly , sharks and rays.
 Large sized fishes are cut into pieces while the small ones are
treated as a whole.
 The process of manufacture consists of boiling the fish in sufficient
quantity of water in large pots to extract oil.
 The cooked mass is then pressed to remove water . The resulting
cake is then dried in sun, taking care to prevent mixing of sand.

12. FISH MEAL
 Large factories are constructed for continuous operation at places
where fish are landed in considerable quantities. The fish is run
continuously to cookers. From where they are passed to screw
presses.
 The pressed material is dried in steam cylinders, pressed material is
dried in steam cylinders, pressed hydraulically to extract oil and
water.
 The solid mass is packed and marketed.
 Fish meal can be stored in air tight sterilized containers for a fairly
long period.
 Fish meal is composed of :-
Proteins 60-80%
Ash 10-15%
Oil 5-6%

13. FISH MANURE
Fish manure is used in many places, and is becoming more and more
popular due to its high nutrient value. Three kinds of manure are
obtained from fish :
1. Fish manure
2. Prawn manure
3. Fish guano

14. FISH MANURE 1 fish manure
 Fish manure is prepared by drying fish in the sun on the sea beach.
When there is an abundant supply of fish or when they are brought
to the shore in spoiled condition and are unfit for human
consumption they are simply spread on beach and dried.
 Mainly mackerels, sardine and few other species are dried to
produce manure.

15. FISH MANURE Prawn manure
 Prawn manure is composed of head , tail and body shell of prawn.
These are separated during the preparation of prawn pulp and from
the waste.
 Prawn manure contains 5-6% nitrogen and 3-4% phosphate and
some lime.

16. FISH MANURE Fish guano
 Fish guano is prepared from sardines that are landed in abundance
on the Malabar coast.
 Fish are cooked and pressed for oil in fish oil factories.
 The solid matter left forms the fish guano and contains 8-10%
nitrogen and phosphates . Fish guano mixes-up with the soil quickly
and is utilised easily by the plants.

17. HYDROLYSED PROTEIN FROM WASTE FISH
 Waste flesh of fish like sharks and skates can be converted into valuable
protein food for human consumption.
 The fish flesh is first minced and washed. This is then boiled with dilute
acetic acid for about one hour at 80* C.
 After washing thoroughly to remove acid and lipids, the fish is pressed
and dried. The product is then treated with petroleum to remove fat
and to improve its quality.
 Remaining protein is insoluble in water and difficult to absorb. It is
therefore , hydrolysed by 10% caustic soda at about 80*C . The liquefied
substance is neutralised by acetic acid. Spray dried to a cream
coloured powder which has natural flavour. The process gives a10%
from raw material, and is rich in proteins (35%). The hydrolysed protein is
easily digestible and is very useful for patients suffering from nutritional
deficiencies.

18. OTHER BY-PRODUCTS
 ISINGLASS
 FISH FLOUR
 FISH GLUE
 FISH SKIN
 SHELLS OF MOLLUSCS

19. OTHER FISH BY-PRODUCTS
ISINGLASS
 It is product from the air bladder of certain fishes like the cat fishes,
perches, scianids. Air bladder of such fishes are exported to prepare
isinglass.

20. OTHER FISH BY-PRODUCTS FISH
FLOUR
 Fish flour is superior quality of fish meal, which is used for human
consumption. It can be mixed with wheat flour (10% fish flour and
90% wheat flour) and is use for enriching nutritive value of bread,
biscuits, cakes etc.

21. OTHER FISH BY-PRODUCTS FISH
GLUE
It is prepared from skin, fins and bones, which are washed , ground and
cooked in steam jackets vessels for 6-10 hours with little acetic acid .
The liquid is separated and concentrated to from fish glue which is
used as an adhesive for book binding, labels, paper boxes etc.

22. OTHER FISH BY-PRODUCTS FISH
SKIN
 The skin of sharks rays is tanned and marketed.
 Dried fins of sharks are exported to china where they are
in demand for the preparation of soups.

23. OTHER FISH BY-PRODUCTS SHELLS
OF MOLLUSCS
 Shells of bivalves and other molluscs are used in the preparation of
lime and bleaching powder.
 Beautiful shells are also used in the manufacture of fancy articles
which are quite attractive and fetch a good price.

24. FISH BY-PRODUCTS
THANK YOU
REFRENCES :
AN INTRODUCTION TO FISHES BY S.S KHANNA
GOOGLE
WIKIPEDIA