Enzyme in fish processing

1. ENZYME IN FISH PROCESSING
Nguyễn Thanh Anh Tuấn ( 13125606)
Phạm Minh Tuấn (13132417)
Lương Hoàng Vũ (13116782)
Đặng Như Ý (13125915)
DH13TPA
Food seminar
Introductor: Dr. Ing. Thien Trung Le

2. I. Introduction
II.Proteasas
 Fish sauce
 Seafood flavouring
 Deskinning
 Collagen extraction
 Protein hydrolyzate
III. Transglutaminase ( TGASE)

3. 1. INTRODUCTION
 Enzyme technology is currently being applied in the fish
processing industry to increase fish meat yield and to
facilitate the processing as well as to improve the quality of
finished products.

4. I. Introduction
II.Proteasas
 Fish sauce
 Seafood flavouring
 Deskinning
 Collagen extraction
 Protein hydrolyzate
III. Transglutaminase ( TGASE)

5.  Proteases can be classified base on:
- Well-characterized proteases.
- pH sensitivities.
- Common names and trade names, preferential specificity
and response to inhibitor specificity.
- => Divided into 3.4.11–19 (the exopeptidases) and 3.4.21–
24 (the endopeptidases or proteinases).

6. -The structure of a protease (TEV protease) complexed with
its peptide substrate in black with catalytic residues in red

7. I. Introduction
II.Proteasas
 Fish sauce
 Seafood flavouring
 Deskinning
 Collagen extraction
 Protein hydrolyzate
III. Transglutaminase ( TGASE)

8.  The product is basically made from a mixture of fish and
salt with a weight ratio of 3:1.
 This mixture is allowed to ferment for more than 6 months
at 30–35◦C for complete
hydrolysis and flavour development
=> Requires a large storage capacity and is
therefore costly

9.  To reduce this capital investment:
- Addition of exogenous proteases to the fermentation can
accelerate the process.
- Papain from unripe papaya
- Bromelain from pineapple stems
-Ficin from figs have all been used.
=> Fish sauce recovery was obtained after 2–3 weeks
of the fermentation process.
=> The flavour characteristics of the finished product are
not like traditional product
cysteine
proteases
Best results

10. I. Introduction
II.Proteasas
 Fish sauce
 Seafood flavouring
 Deskinning
 Collagen extraction
 Protein hydrolyzate
III. Transglutaminase ( TGASE)

11.  Proteolytic enzymes can aid the extraction of flavour
compounds from shells and other materials.
 Shrimp flavouring can be used as an
additive in surimi-based products and cereal-based
extrusion products like shrimp chips.
=> Proteases are used in this process that also been used to
recover flavour from oysters.

12. I. Introduction
II.Proteasas
 Fish sauce
 Seafood flavouring
 Deskinning
 Collagen extraction
 Protein hydrolyzate
III. Transglutaminase ( TGASE)

13.  The enzyme solution contained unspecified proteases
and carbohydrases.
 The presence of carbohydrases, although not essential,
enhanced the skinsolubilization process, presumably by
loosening the collagenous layer
 There by facilitating increased access of the proteases to
the denatured collagen.
 Ex: Deskinning of tuna (Thunnus spp. and related
genera) was achieved by preheating with steam to 60◦C,
followed by digestion of the pre-treated skin with a
complex mixture of proteases and carbohydrases at
∼50◦C.

14. I. Introduction
II.Proteasas
 Fish sauce
 Seafood flavouring
 Deskinning
 Collagen extraction
 Protein hydrolyzate
III. Transglutaminase ( TGASE)

15.  Collagen is commonly extracted using an acid-
solubilization process, in which non-collagenous matter,
pigment and lipids are first removed by alkali solution (
Acetic acid)
=> The acid process gives a low yield of collagen.
=> Covalent cross-links at the telopeptide region of
collagen molecules are not readily solubilized by acid.

17.  Fish pepsin is another promising enzyme for collagen
extraction. It can be extracted or recovered from fish
processing by-products, especially fish stomach.
=> The cost of pepsin can be reduced and the visceral
by-products can be fully utilized.
=> Those cross-links can be cleaved by pepsins without
damaging the integrity of triple helix of collagen

19. I. Introduction
II.Proteasas
 Fish sauce
 Seafood flavouring
 Deskinning
 Collagen extraction
 Protein hydrolyzate
III. Transglutaminase ( TGASE)

20. Fish protein hydrolyzed can be prepared with
the addition of protease to increase the
endogenous hydrolytic activity and shorten the
hydrolysis time.
The different proteases exhibited varying
characteristics, including optimal pH and
temperatures.

23. I. Introduction
II.Proteasas
 Fish sauce
 Seafood flavouring
 Deskinning
 Collagen extraction
 Protein hydrolyzate
III. Transglutaminase ( TGASE)

24.  Endogenous TGase
-The protein glutamine γ -glutamyltransferase (EC
2.3.1.13), is a catalyst for the acyl transfer reaction
between γ -carboxyamide groups of glutamine residues
in proteins or peptides and various primary amines
=> Formation of covalent cross-links between proteins is
the basis of the ability of TGase to modify the physical
properties of protein foods.

26.  Endogenous TGase has different molecular
weights depending upon fish species.
 The optimal pH and temperature vary with
species that depending on the temperature of
measurement.

27. - The collagen and gelatin from fish, especially
from cold water fish,have low gelling temperatures
and melting it cannot form a gel at room
temperature.
- MTGase have been
used to improve the
bloom strength of
gelatin gel from fish
origin via cross-
linking of gelatin
molecules in the gel
matrix.

28. CONCLUSION
 Different enzymes have been used in seafood processing
as the aid to improve yield and quality.
 Modes of action of different enzymes vary.
 The processes involved should be carefully considered so
as to maximize the benefit of the enzymatic reactions
employed.

29.  http://www.cryst.bbk.ac.uk/PPS2/course/section12/
serprot1.html