This document discusses fish protein concentrates (FPC) and protein isolates. It describes how FPC is produced using chemical solvent extraction to remove water and lipids from fish, producing a product that is 75-95% protein. Three types of FPC are defined based on odor, flavor and fat content. Protein isolates are also discussed as refined protein sources with over 90% protein content produced from plant and animal sources using precipitation and centrifugation. Potential applications of protein isolates in foods are mentioned.

1. FISH PROTEIN ISLOATES ANS
CONCENTRATES
FOT 212
CA-2

2. FISH PROTEIN CONCENTRATE:
• INTRODUCTION: Fish protein concentrates are defined as
those products obtained from fish in which the protein is
more concentrated than the original raw material. It has
been used in various parts of world. The FPC's produced
are, in general, bland tasting and vary in color from white
to dark tan. They contain between 75 and 95 percent high
-quality protein and they exhibit limited functional
properties according to standards set by industry for high
protein foodstuffs. Today several pilot plants and full-scale
industrial plants have been built. Most of these plants
produce FPC by solvent (usually isopropyl alcohol)
extraction procedures.

3. • PRINCIPLE TYPES OF FPC The Food and Agriculture Organization of
the United Nations defines three types:
• Type A : virtually odorless and tasteless powder having a maximum
total fat content of 0.75 percent.
• Type B : powder having no specific limits as to odor or flavor, but
definitely having a fishy flavor and a maximum fat content of 3
percent.
• Type C : normal fish meal produced under satisfactory hygienic
condition. These three types, all of which in a sense resemble fish
meal. These are typically made by hydrolyzing fish protein by means
of enzymes or other chemicals and then concentrating the product
into a paste or extract. The fat content is specified when defining
types of FPC. The protein content of FPC depends on the raw material
used and the extent to which water has been removed, but the
products normally contain at least 65 percent protein in and, in type A

4. • PROCESSING OF FPC Chemical methods use solvents to remove
water and lipids from fish. Numerous chemical methods have
been developed in various parts of the world to produce FPC.
There are two important methods first one is solvent extraction
method and second one is isopropyl alcohol extraction. The
manufacture of types A and B is described here, since type C is
simply hygienically prepared fish meal. Water and fat together
constitute about 80 per cent of the whole fish, with the fat itself
in some species accounting for up to about 20 per cent at
times. The manufacture of FPC involves removal of most of the
water and some or all of the fat. Methods developed so far are
based mainly on the use of chemical solvents to remove the
water, fat and fishy-tasting components, either from raw fish or
from fish meal. The solvents most successfully used to make
FPC type A are the alcohols, for example ethanol or propanol;
ethylene dichloride is also used. Normally the solvent is
recovered and used again and again

5. ADVANTAGE AND USES OF FPC
• Advantages of FPC : First, of course, because it is concentrated;
untreated and unprocessed foods do not generally contain
more than about 20 percent protein, whereas FPC contains
about 80 per cent. Secondly, the quality of the protein is high;
by this is meant that the amino acids which make up the
protein are present in just the right balance for human
nutrition. Other foods such as cereals may contain useful
amounts of protein but are frequently deficient in one or more
of the amino acids that are essential for growth. However, it is
true to say that this highly nutritious, concentrated, stable
foodstuff is now available without as yet any clear demands
appearing for its use. HOE TO USE FPC : It has to be
incorporated in other foods such as bread, biscuits, soups and
stews at a level that does not affect their normal properties.
Good results have been obtained with macaroni products, a
milk shake drink, spaghetti sauce, infant foods, dietetic foods
and breakfast cereals. FPC can be eaten more or less as it is, or
used as a flavoring in soups or stews.

6. PROCESSING OF FPC
• Chemical methods use solvents to remove water and lipids
from fish. Numerous chemical methods have been developed in
various parts of the world to produce FPC. There are two
important methods first one is solvent extraction method and
second one is isopropyl alcohol extraction. The manufacture of
types A and B is described here, since type C is simply
hygienically prepared fish meal. Water and fat together
constitute about 80 per cent of the whole fish, with the fat itself
in some species accounting for up to about 20 per cent at
times. The manufacture of FPC involves removal of most of the
water and some or all of the fat. Methods developed so far are
based mainly on the use of chemical solvents to remove the
water, fat and fishy-tasting components, either from raw fish or
from fish meal. The solvents most successfully used to make
FPC type A are the alcohols, for example ethanol or propanol;
ethylene dichloride is also used. Normally the solvent is
recovered and used again and again

8. PROTEIN ISOLATES
Protein isolates are refined form of protein containing the greater amount of protein with greater
digestibility. Nowadays it’s the major source of cheap proteins especially for athletes, bodybuilders,
vegetarians, and has gained wide application in various beverages and dairy industries, and infant
foods
due to its different functional properties. It is widely produced from deoiled cake of legumes such as
peanuts, cowpeas, soybeans, etc and animal sources like fish and milk by a combination of isoelectric
and alkaline precipitation using H2SO4 and NaOH, followed by centrifugation to obtain the pure
isolates which can further be dried to powdered form of about 90% protein. The problem of
antinutritional factors in legumes can be successfully reduced by these processing methods.
Protein isolate are obtained from different plant and animal sources
• Proteins that are utilised in food processing are of various origins, and can roughly be
classified into animal proteins (gelatins), vegetable proteins (e.g. peanut protein, soy protein,
wheat proteins, Almond protein, canola meal protein etc.), and animal derived protein (e.g.
milk proteins).

9. • Fish protein isolate is a protein concentrate which is prepared from fish muscle
without retaining the original shape of the muscle. It is not generally consumed
directly, but used as raw material for production of other value added products.
• Fish protein isolate does not retain the original shape of muscle, and is normally
utilized as ingredient for the production of value added products. It is still a good
source of protein for the production of ready to eat fish products.
• The overall processes involved are simple. The proteins of the muscle tissue are
first solubilised. The solubilisation can be accomplished by addition water with alkali
added to approximately pH 10.5 or higher, or with acid added to about pH 3.5 or
lower. It is usually necessary to choose the pH at which the consistency of the
solution decreases to a value that allows the removal of undesirable material.
• The mixture is then centrifuged, and due to density differences the oil rises to the
top and can then be removed. Other insoluble impurities such as bone or skin are
also sedimented at this stage.
• The muscle protein are then precipitated and collected by a process such as
centrifugation.

11. Antinutritional factor in protein isolate
Several studies have reported the preparation and functional
properties of protein isolates and concentrate Legumes contain
some anti-nutritional factors such as lectins, saponin,
haemagglutinin, protease inhibitor, oxalate, goitrogen, phytates,
trypsin inhibitor and tannin. These compounds reduce protein
digestibility and availability. Some anti-nutritional in legumes have
been reported to have health benefits. Tannin, a polyphenolic
compound is reported to possess antioxidative property .

12. Application of protein isolate in food
systems.
Protein isolates are the acceptable ingredients
for dairy application due to their fine particle
size and dispersibility, Emulsification, emulsion
stability, colour and flavour are critical in dairy
application. Isolates (especially soy proteins) are
being used to fortify all type of pasta products
such as macaroni, spaghetti, to improve the
nutritional value etc

13. Protein isolates are important sources of protein
with high lysine content. Isolates from different
legumes varied slightly in physiochemical and
thermal properties. They are used as
proteinaceous ingredients in many food products
such as salad dressing, meat products and
dessert. Whey proteins are mainly used in
beverage applications, due to their health
benefits

14. Neutralised protein isolates are often highly dispersible and form
gel under appropriate aqueous conditions. They have both
emulsifying and emulsion stabilising properties, and are excellent
fat and water binders, For this reason, they are widely used in
processed meat products, as well as both coarse and fine
emulsions (e.g., patties, loaves and sausages) . Different protein
products such as whey protein, soy protein isolates, wheat
gluten, rice bran protein, peanut protein, and cottonseed proteins
where investigated for film development.

15. CONCLUSION
Protein isolates shows a lot of potential to combat the problem of
malnutrition. The underutilised plant and animal sources can be
exploited in order to extract the proteins and make them available
for used as food supplements. Research is needed compared the
benefit of different protein isolates and their benefit as food
supplements.