Enzymes in the food industry and its uses.ppt

Enzymes in the food industry

1. Lecture 12Lecture 12
ENZYMES IN THE FOOD INDUSTRYENZYMES IN THE FOOD INDUSTRY
1

2. What are enzymes?
Enzymes are highly specialized proteins that catalyze
specific biochemical reactions
Proteins are chains of individual amino acids

3. Enzymes – General properties
They are essential for reactions to occur in living (and dying) cells
They can have a dramatic impact on the quality deterioration of
many foods
They can be used to perform positive reactions in food and
beverage processing
Have specific ability to convert a particular substance into a
particular product

Very rapid action

Only need small amount

Can easily control them by adjusting their environment,

They are all natural and non-toxic

4. Why are enzymes important in the food industry?
Added or used to cause particular reaction
Advantages

Natural, Nontoxic

Catalyze specific reactions

Active under mild conditions

Active at low concentrations

Can control rate of reaction
Can be inactivated
Used as indicators of proper processing
Used to measure another compound in the food

5. Back groundBack ground: :
-For many thousand of years , man has used naturally -For many thousand of years , man has used naturally
occurring m.o (bacteria, yeast, mould & the enzymes they occurring m.o (bacteria, yeast, mould & the enzymes they
produced to make food such as :“Bread, Cheese, beer& Wine” produced to make food such as :“Bread, Cheese, beer& Wine”


Enzymes Enzymes & & FoodFood
In bread making , amylase E is used to breakdown flour into In bread making , amylase E is used to breakdown flour into
soluble sugars , which are transformed by yeast into : Alcohol soluble sugars , which are transformed by yeast into : Alcohol

& carbon dioxide. This make bread rise.& carbon dioxide. This make bread rise.
Today, enzymes are used for an increasing range of application:
(Bakery, cheese making, starch processing , tenderizing of meat,
production of fruit juice& other drink).
Here they can improve texture, appearance, nutritional value& may
generate desirable flavor &aroma.
Use of enzymes in meat
Found their use in tenderization of meat - dates back in 500yrs ago when
Mexican Indians wrapped meat in papaya leaves during cooking

6. Enzymes used in food industry can be derived
from 3 sources:
1- Animal
2-Vegetable
3-Microbial
Enzymes produced for industry
1- Protease
2-Amylase
3-Glucose isomerase
4-Glucose oxidase
5-Renin
6-Pectinase
7-Lipase

7. There are 4 enzymes commonly used in food preparation that are
derived from animal tissue .
1-Rennet: an extract of fourth stomach of calf & is rich in rennin
& pepsin
Both of these are protease that change milk to cheese.

2-Lipase : used to impart buttery flavor to oils by degrading some
of lipids & to hasten the aging of cheese.
3- Pancreatin: is rich in plethora of protease .

-is used to modify protein to make it more easily digested.

4- Trypsin : used for the same purpose.
*Pancreatic tissue& its derivatives are the ingredient of infant food
formulas to break down the protein for children who cannot digest
it.

8. Rennet
An enzyme obtained from fourth stomach of
ruminant animals, and from some microorganisms
Cleaves particular bond in K-casein of milk to
initiate milk coagulation
Coagulates milk protein in cheese making
Aids in development of flavor and texture in
ripened cheese.
Mild heat speeds up the enzyme reaction.

9. There are 3 major plant-derived protease used
commercially today
-Papain is derived from papaya plant.
-Bromelain from the pineapple plant.
Papain& bromelain which are commonly used as meat
tenderizers
-Ficin from the fig
*Ficin being more limited in use due to its more
dangerous proteolytic activity.
-Barley amylase is also used to make maltose syrup.

10. Other sources of enzymes have been cited for meat
tenderization such as B.subtilis; A.oryzae & pancreatin
The recent explosion of interest in enzymes involve the 3
rd
source
(Microbial)
The growth of m.o on nutrient media allow these m.o to produce varied

enzymes as a part of their natural metabolic function & this process is

commonly referred to as (Fermentation)
Use of bacterial collagenases during cooking
Endogenous enzymes ( Cathepsin B and D)
Mechanically Recovered meat -15-40% of bone weight –
used in soups and gravies (bacterial Alcalase and
neutrase) or animal feeds

11. Important food enzymes
HYDROLASES
They all have in common that they break bonds with the help of
water
1. Glycoside hydrolases
A) Enzymes that hydrolyze starch (glycosidic bonds)
-amylase

Hydrolyses -1-4 glycosidic bonds within starch

Results in dextrins, maltose and maltotriose
-amylase

Hydrolyses -1-4 glycosidic bonds from the non-reducing
end of starch

Results in maltose
Glucoamylase

Hydrolyses -1-4 and -1-6 glycosidic bonds in starch

Can hydrolyze all the way to glucose
Pullulunase

Hydrolyses -1-6 glycosidic bonds in starch
These enzymes are naturally present in the food or are found in
microorganisms added to the food

12. Food importance of the glycoside hydrolases
Corn syrup production
Using a cocktail of enzymes,
starch can be converted to a
glucose syrup (dextrose)
Start with -amylase to
break amylose and
amylopectin to smaller units
Then use glucoamylase to
break down to glucose
If maltose is desired use -
amylase and pullulanase

13. Baking
-amylases are important to “dextrinize” the disrupted starch
granules (rupture during milling) and the dextrins are
hydrolyzed to maltose by -amylase  gives fermentable
sugar for yeast to produce CO
2 (essential for rising of the
bread)
On baking further, amylases on the gelatinized starch  plays
an important role in the final texture and quality of bread
Amylases added to bakery products can minimize staling
Need to add -amylases to some flours (when harvested in
dry climates)
Brewing
High level of amylases in barley malt (no need to add more)
During mashing (milled barley malt and water at 50C)
amylases hydrolyze starch to give maltose for yeast to utilize
and produce CO
2 and ethanol

14. B) Invertase
An enzyme that hydrolyzes the glycosidic bond between
glucose and fructose in sucrose

Results in invert sugar (free glucose and fructose)

Popular in the confectionary industry because invert
sugar is sweeter than sucrose and has less tendency to
crystallize
C) Lactase
An enzyme that hydrolyses the glycosidic bond between
galactose and glucose in lactose

Increases sweetness and solubility of the sugar

Done in the dairy industry to minimize crystalization in
ice cream and to produce lactose free products

15. 2. Pectinases
Occur widely in fruits and vegetables and are responsible for the
degradation of pectic substances
Pectin methyl esterase

Hydrolyze the methyl ester linkages of pectin

Causes loss of cloud in citrus juice (big problem)

Converts colloidal pectin to non-colloidal pectin

Add this enzyme when clarity is desired (e.g. apple juice)
PME
90C for 1 min
O OO
O O OO
COOCH
3
COOH COOCH
3
O OO
O O OO
COOCH
3
COOH COOCH
3
O OO
O O OO
COOCH
3
COOH COOCH
3
O OO
O O OO
COOCH
3
COOH COOCH
3
O OO
O O OO
COOH COOCH
3
O
O OO
O O OO
COOH COOCH
3
O
C a
O OO
O O OO
COOH COOCH
3
O
O OO
O O OO
COOH COOCH
3
O
C a
O OO
O O OO
COOH COOCH
3
O
O OO
O O OO
COOH COOCH
3
O
C a
O OO
O O OO
COOH COOCH
3
O
O OO
O O OO
COOH COOCH
3
O
C a

16. 3. Proteases
Enzymes that hydrolyze peptide bonds in proteins
A) Papain
Found in papaya
Broad pH (3-11) and temperature stability

For this reason very popular for a variety of food
applications
1. Used as a meat tenderizer on inferior meat cuts (can also use
slice of pineapple on meat)
The enzyme makes its way into the muscle and
hydrolyzes primarily connective tissue proteins
(collagen etc.) and softens muscle

Have to use low amount to prevent liquefaction of
muscle

Other popular tenderizing enzymes are ficin (from figs),
bromelain (from pineapple) and microbial proteases

17. 2. Papain can also be used to clear turbidity (chill haze) in beer
When bottled or canned beer is kept below 10C (50F) a haze can
form

Due to interactions of proteins/polypeptides and tannins in
beer
This can be prevented using chill-proofing

Protease (papain mostly used) added during post-fermentation
maturation to hydrolyze the proteins/polypeptides to prevent
large aggregates to form on cooling

18. B) Digestive proteases
Trypsin & Chymotrypsin

Found in animal pancreas

Can cause quality problems in muscle foods if
contamination from intestines occurs  over-
softening of the meat

They are often used to make protein hydrolysates for
the food, beverage and the pharmaceutical industry

Most active at pH 7-9
Pepsin

Very acidic activity optima (pH 1.8)
Somewhat limits its use

Used in cheese making, chill proofing and also in
making protein hydrolysates

19. Chymosin (rennin)

Essential for the manufacture of good quality cheeses

Found in the fourth stomach of suckling calf's

Very expensive so it has been engineered into a bacteria that
mass produces it

Has a very specific activity
Hydrolyzes only one bond in к-casein, one of the many
proteins that make up the milk casein protein complex (к-, -,
-casein)
This breaks up the casein complex (micelle) and it aggregates
leading to a clot, the first step in cheese production

20. C) Microbial proteases
Several fungal and bacterial proteases are used in the food
industry
Fungal proteases

Some have almost equal ability to form cheese cloths
like chymosin
A protease cocktail from Aspergillus oryzae is used to
partially break down bread proteins (glutens) to
reducing mixing time and making them more extensible

Some are added to help with flavor and texture
development and speeding up fermentation in
fermented dairy products

Fungal proteases are also used to tenderize meat
Bacterial proteases
Subtilisin from Bacillus subtilisin is popular and is used
in combination with papain in beer chill proofing

21. 4. Lipases
Enzymes that all hydrolyze ester bonds between fatty acids
and a glycerol molecule

Work at the water-oil interface
Two classes
a) 1,3-lipases: preferentially hydrolyze ester bonds at SN1
and SN3
b) 2-lipases preferentially hydrolyze ester bonds at SN2

22. Lipases have a dramatic impact on the quality of food
products
A) Lead to hydrolytic rancidity
BAD when
Free fatty acids released in muscle foods and react to
proteins to denature them and give a tough texture
(happens on freezing muscle)
they are not inactivated in milk; release short chain fatty
acids that are very volatile and can also oxidize
GOOD when
Used in fermented products
Extremely important in ripening of cheeses and dry-
sausages
Short chain fatty acids released from milk fat produces
the characteristic odor and flavor of these products (C:8
especially)

23. B) They can be used to modify the properties of lipids

Very popular application in the margarine industry to modify
lipid crystal structure to give different textures and melting
points

Also used to produce mono and diglycerides for use as
emulsifiers
The enzyme is located in
the water droplet of a
water-in-oil emulsion
and acts on the oil
surrounding the water
droplet

24. ISOMERASES
They all catalyze the intramolecular
arrangement within a molecule
Glucose isomerase
The most important for the food industry
Catalyzes isomeric rearrangement of
glucose to fructose (converts an aldose
to a ketose)

Gives a sweeter product than corn
syrup
Sweetness glu = 70; fru = 170;
sucrose = 100

Product called high fructose corn
syrup

Made from corn syrup (which is made
by amylase digestion of starch)
Glu isomerase
pH 7
50-60C
Corn
Syrup
42% (HFCS) 52%

25. OXIDOREDUCTASES
Enzymes that catalyze the oxidation or reduction of substrates
A) Lipoxygenase
Found in a wide variety of plants (primarily legumes) and have also been
identified in animal tissue (e.g. in the skin of fish)
Specific for the oxidation of fatty acids that have a cis, cis penta-1,4-diene unit
Three naturally occurring fatty acids that can be substrates

Linoleic acid (2 double bonds)

Linolenic acid (3 double bonds)

Arachidonic acid (4 double bonds)

26. Importance of lipoxygenases in foods
Desirable

For bleaching of wheat and soybean flours

It contributes to the formation of S-S bonds in gluten in dough, thus one
does not have to add chemical oxidizers
Undesirable
Breakdown products of hydroperoxides give off-flavors and odors
Oxidation products (the free radicals or hydroperoxide) can bind and/or
oxidize proteins to lead to textural problems
Lipid oxidation also leads to nutritional loss of essential
polyunsaturated fatty acids
Vitamins may also be oxidized by the oxidation products
Chlorophylls and carotenes can be bleached

27. B) Polyphenol oxidase (PPO)
◦Found in plants (fruits and
vegetables), animals (including
humans), insects and microbes
◦Catalyzes the oxidation of
phenolic compounds (mono
and/or diphenols) in the
presence of O2 to give quinones
which polymerize into melanin
pigments (desirable or
undesirable)
◦Its activity can be inhibited by:
Removing O2
pH < 4.5 (lemon juice)
Ascorbic acid (vit-C)
EDTA
Undesirable browning of apples,
bananas, mushrooms, shrimp,
lobster, human freckles?
Up to 50% economic loss of tropical
fruit due to PPO activity
Desirable browning of tea, coffee,
cocoa, raisins, prunes, tobacco,
human tan, freckles?
Polymerizes  Melanins

28. Other Examples of Enzymes in Foods
Milk
Lactase
Alkaline phosphatase
Lipases
Plasmin
Fresh vs. canned pineapple
Bromelain breaks down gelatin in “Jello”
Meat tenderizer – uses bromelain, ficin, or papain
Blanching of vegetables – catalase and peroxidase
Cloudy vs. clear apple juice (Pectinase)
Onions – enzyme alliinase acts on sulfur cmpds.

29. An overview of enzymes used in food and feed processing
Class Enzyme Role
OxidoreductasesGlucose oxidase Dough strengthening
Laccases Clarification of juices, flavor
enhancer (beer)
Lipoxygenase Dough strengthening, bread
whitening
Transferases Cyclodextrin
Glycosyltransferase
Cyclodextrin production
FructosyltransferaseSynthesis of fructose oligomers
Transglutaminase Modification of viscoelastic
properties, dough processing, meat
processing
Lyases Acetolactate
decarboxylase
Beer maturation
Isomerases Xylose (Glucose)
isomerase
Glucose isomerization to fructose
Contd….

30. An overview of enzymes used in food and feed processing
Class Enzyme Role
Hydrolases Amylases Starch liquefaction and sachcarification
Increasing shelf life and improving quality by
retaining moist, elastic and soft nature
Bread softness and volume, flour adjustment,
ensuring uniform yeast fermentation
Juice treatment, low calorie beer
Galactosidase Viscosity reduction in lupins and grain legumes
used in animal feed, enhanced digestibility
Glucanase Viscosity reduction in barley and oats used in
animal feed, enhanced digestibility
Glucoamylase Saccharification
Invertase Sucrose hydrolysis, production of invert sugar
syrup
Lactase Lactose hydrolysis, whey hydrolysis
Lipase Cheese flavor, in-situ emulsification for dough
conditioning, support for lipid digestion in young
animals, synthesis of aromatic molecules
Contd….

31. An overview of enzymes used in food and feed processing
Class Enzyme Role
Hydrolases Proteases
(chymosin, papain)
Protein hydrolysis, milk clotting, low-allergenic
infant-food formulation, enhanced digestibility and
utilization, flavor improvement in milk and cheese,
meat tenderizer, prevention of chill haze formation
in brewing
Pectinase Mash treatment, juice clarification
Peptidase Hydrolysis of proteins (namely, soy, gluten) for
savoury flavors, cheese ripening
Phospholipase In-situ emulsification for dough conditioning
Phytases Release of phosphate from phytate, enhanced
digestibility
Pullulanase Saccharification
Xylanases Viscosity reduction, enhanced digestibility, dough
conditioning

32. -An innovative enzyme for the meat, fish &
dairy industries.
-It is brand of transglutaminase
Is enzyme that occur widely in nature .
-It has been used successfully by the European &
Japanese meat, fish, dairy industries
ACTIVA
Activa catalyses the formation of stable , fine protein
network by creating covalent bonds between 2 amino
acid (glutamine &lysine ) so called (G-L) bonds,
these bonds are heat resistant.

34. --In fish, seafood, meat industries - In fish, seafood, meat industries -
Used to bind pieces of fish or meat together for :Used to bind pieces of fish or meat together for :

--Portion control . Portion control .
-Add value to meat off cuts.-Add value to meat off cuts.
So Lead To :
No need to use heating, freezing for binding

Possible to slice the recombined meat in the row state.

Easy to handle, no effect on flavor.

Application


Improve the structure of fish, cooked meats, hams& sausages.
-standardizing texture.
-improving slice ability .
-improvement to breaking strength.
-Adding more juiciness.
-Reduction of other ingredient as (Phosphate)

35. For enzymes used in the food industry particular benefits are
Better use of raw materials (juice industry),
Better keeping quality of a final food and thereby less wastage of
food (baking industry)
Reduced use of chemicals in the production process (starch
industry).
For enzymes used in the feed industry particular benefits include
a significant reduction in the amount of phosphorus released to
the environment from farming
Benefits

36. • 
There are several advantages of using Genetically Modified
Microorganisms for the production of enzymes, including:
It is possible to produce enzymes with a higher specificity and
purity
It is possible to obtain enzymes which would otherwise not be
available for economical, occupational health or environmental
reasons
Due to higher production efficiency there is an additional
environmental benefit through reducing energy consumption and
waste from the production plants

37. Disadvantage
Cause allergies if in powder –solutions
Injurious to health – in stomach- attacking body
tissue
Microbial and fungal –toxins (consumer view)
To-date , there have been no reports of consumer allergy To-date , there have been no reports of consumer allergy
to enzyme residues in food . to enzyme residues in food .

The levels of enzyme residue appear in food are so low to cause The levels of enzyme residue appear in food are so low to cause
allergy . allergy .

Like all proteins, enzymes can cause allergic reactions when Like all proteins, enzymes can cause allergic reactions when
people have been sensitized through exposure to large people have been sensitized through exposure to large
quantities.quantities.



38. Novozymes’ enzymes produced by Novozymes’ enzymes produced by
genetically modified microorganismsgenetically modified microorganisms
Novozymes A/S markets a range of Novozymes A/S markets a range of
enzymes for various industrial enzymes for various industrial
purposes. Many of these enzymes purposes. Many of these enzymes
are produced by fermentation of are produced by fermentation of
genetically modified microorganisms genetically modified microorganisms
(GMMs)(GMMs)

39. Thank YouThank You