Fish processing

1. MISCELLANEOUS BY-PRODUCTS: fish
maws and isinglass, pearl
essence,fertilizer,beche-de-mer,processing of
snail meat,and jelly fish.
Ajeet soni
Ph.D Scholar
COFS, CCSHAU
Dept. Of Fish Processing
Technology

2. INTRODUCTION
• Fish undoubtedly is one of the most nutritious of foods available for
human consumption .fish flesh contain very high amounts of body oil.
• Judiciouss and economic utilisation of fish should have a programme
of proper disposition of such fish and fishery waste by processing
them into different products intended for human consumption, animal
nutrition or industrially useful products.
• Traditional fishery by-products are fish meal, fish body oil, liver oils,
etc.
• Fish protein concentrate, fish albumin, glue, getatin, pearl essence
etc. are some other bye products generally processed out of fish and
fish waste.

3. FISH MAWS
• The air bladder present inside the fish also referred as swim
bladder consist of several membranous layers rich in
collagen. located in the abdominal cavity below the vertebral
column.
• air bladder helps the fish in regulating its specific gravity
thus enabling it to survive at different level of water.
• cleaned and dried air bladder is called fish maws. which is a
excellent raw material for producing good grade gelatine or
glue. Hakes , sturgeons and carps are good sources of air
bladder.
• In India they are collected from eel,catfish,threadfins and
Jew fish.

4. 1. Bladder are separated from backbone
during filleting/dressing.
2. Scrapped gently and preserved by salting
3. Then it is split open.
4. Washed thoroughly.
5. Black outer membrane are removed by
scraping.
6. dried .
PROCEDURE

5. ISINGLASS
• Dried fish maws are also known as isinglass.
• Air bladders are soaked in water for several hours.
• Cut into pieces of the required sizes and pressed between
hollow iron rollers
• Converting them into thin strips of 3 to 6 mm thickness .
• After partial drying ,they are again pressed into still thinner
isinglass ribbons .
• further dried by suspending in warm rooms.
• They are then either rolled into coils or packed in leaf or
book forms.

6. USES
• Isinglass swells in hot water, dissolves readily
in most dilute acids and alkalis but does not
dissolve in alcohol.
• It is used for clarifying beverage like cider,
wine, beer, vinegar.
• It is also finds use as an adhesive base , in
confectionery products , indian ink and as an
efficient adhesive for glass, pottery and
leather.

7. • Pearl eessence is a suspension of crystalline guanine
in water or an organic solvent. chemically guanine
combines with collagen and calcium phosphate
yielding a silvery white shining.
• Guanine is the iridescent material found in the
epidermal layers and scale of most pelagic species of
fish like oil sardine, mackerel, herrings etc.
• When guanine particles are deposited on the inside
surface of solid beads, an optical effect similar to that
of real pearl is obtained .
Pearl essence

8. MANUFACTURE OF PEARL ESSENCE FROM
SCALES
• Scales are removed from ribbon fish with a bamboo spatula.
there are two methods to obtain pearl essence.
1. separation of pearl essence by petrol: the scales are
soaked in petrol to separate pearl essence from protein
and water. the pearl essence is transferred into petrol
where upon it floats to the surface .the separated pearl
essence is then filtered to obtain the fine particles of
essence. The precipitate is poured again into petrol.
2. Protease is added to the fish scale to dissolve fragments
of skin , benzol or ether is added to the digested scales.
then pearl essence will float to the surface .it is then
separated and filtered.

9. USES
• The most important use of pearl essence
is the manufacture of artificial pearls. It is
used as spray or dip for several items to
impart an iridescent sheen reminiscent of
pearls. it is used on such diverse articles
as shoe, pencil, fishing rod spectacle
frame ,walking stick, ash tray, vanity bag,
book cover and even in finishes for
textiles.

10. BECHE-DE-MER
• Beche-de-mer is the commercial name for cvired
holothurians, commonly known as sea cucumbers.
• In India, the beche-de-mer industry depends almost on a
single species viz. Holothuria scabra found in the Gulf of
Mannar, Palk Bay, Andaman and Nicobar
Islands,Lakshadweep and also in the Gulf of Kutch.
• The animal usually burrows in sandy or muddy bottom and
feed on the nutritive material contained in it.

11. PROCESSING
• Processing of beche-de-mer is simple and involves the
following steps :
1. Thorough evisceration before boiling.
2. Boiling without the addition of water till the
animals shrink to half of their length and
emit a distinctive cooked odour.
3. Burial in damp sand for 12 to 18 hours.
4. Removal of the chalky external coat.
5. A second boiling in sea water for 20 minutes.
6. Full drying upon wire net trays raised above the ground or
half-sun drying.

12. FERTILIZERS FROM FISH WASTE
• Fish is a good source of essential nutrients like nitrogen,
calcium, phosphorus and other elements essential for
plant growth. Fish or fish waste , being organic in nature,
is a slow release fertilizer because the organic
constituents have to undergo several photolytic changes
by the soil bacteria before they become available to plant.
• Fish offal or low value fish can be converted to digesting
them with sulphuric acid. Acid digestion converts the
protein to ammonium sulphate and also makes the bone
phosphate available for absorption by the plants.

13. • As an alternate to acid digestion , another technique
employed is to treat the fish with urea. the treatment
solubilises the fish tissue. One advantage of the process is
that on manuring , the urea immediately becomes
available for plant nutrition.
• One of the short comings of a fertilizer processed
according to the above method is the poor balance
between components like nitrogen, phosphorus and
potassium . this can be overcome if the fish material is
digested with potassium hydroxide and the excess alkali is
neutralised with phosphoric acid. This process make up the
deficiencies of potassium and phosphorus in the fish
fertilisers.

14. PROCESSING OF SNAIL MEAT
•Snail meat is now becoming a highly valued
delicacy in recent times. It is also known and
referred to as “Congo meat” in Nigeria.
•Snails constitute an important source of
animal protein for many coastal communities.
• Snail meat consumption as we all know has
become a lifestyle for some people especially
those eating it on medical grounds.

15. PROCESSING PROCEDURES:
Snail meat for export must be processed with great care so as to
increase its marketability. Below are the procedures that must be
followed for processing snail meat for export.
1. The snail should be starved for about 24 hours in
other to empty their stomach
2. Prepare enough quantity of water by boiling at
greater than 70 degrees centigrade and transfer into a
bucket or drum
3. Add enough lumps of alum (potassium or ammonium
aluminum sulphate)
4. Transfer the snails into hot water and cover up
immediately

16. 5. After 2 to 3 minutes, open the lid and pour off
the resulting dirty from the hot water
6.Cool under running tap
7. With ease, shake off each snail from its shell
into clean, cool water
8. Remove offal
9.Rinse in two changes of clean cool water
10. At this time, it is ready for immediate
consumption or packaging for export.

17. PROCESSING OF JELLYFISH
• Processing technique is nothing but displacement of body fluids
of the animal by
chlorine powder and salt solution in a slow
and long process. It involves 6 stages, the first
5 stages are of cleaning the animals and the
last stage is packing.

18. I stage: The washed and cleaned jellyfishes
are placed in the first tank, containing 3 kg/
tank of chlorine powder for 3-6 hours soon
after they are bought from the landing places.
II stage: The jellyfishes are then transferred
into the second tank containing 150 kg/tank
of sodium chloride (common salt) and kept
for 24 hrs. Now the weight of a single jellyfish
is reduced to 50% of the body weight.

19. III stage: Again, the jellyfishes are transferred
into the third tank containing 150 kg/tank of
sodium chloride for 24 hrs. which further
reduces body weight.
IV stage: The jellyfishes are again transferred
into the fourth tank containing 150 kg of
sodium chloride for 24 hrs. which further
reduces the weight.
.

20. V stage: The samples are kept on steel
tables and massaged after which they are
kept one above the other. The fifth stage
involves removing of the extra-unwanted
thistles and then they are layered one
above other in the fifth tank.
Packing stage: The flattened umbrellas are
piled in polythene bags one above the
other and packed in wooden boxes for
export

21. REFERENCES
• 1.FIH PROCESSIN TECHNOLOGYAND PRODUCT
DEVELOPMENT – A. S. NINAWE AND K.
RATHNAKUMAR
• 2.POST HARVEST TECHNOLOGY OF FISH AND FISH
PRODUCTS – K.K. BALACHANDRAN
• 3.FAO MANUAL

22. THANK