5.-Application-of-Colligative-Properties-to-Food-Processing.pptx

Lesson
5 Application of
to Food Processing

Application of Boiling Point Elevation to Food Industry
Vapor Pressure and Boiling
During evaporation, the molecules which leaves a liquid
creates an upward pressure because they collide with air
molecules, and this upward pressure is known as “vapor
pressure”.
While “boiling point” of a liquid is the temperature at which
its vapor pressure equals the external atmospheric
pressure.

Vapor Pressure and Boiling
Boiling occurs through bubble formation, and the bubbles are
formed when atoms or molecules of liquids spread out
enough to change from its liquid phase to gaseous phase.
The most important factors affecting the boiling point of a
liquid are atmospheric pressure and the vapor pressure of
the liquid.

Atmospheric Pressure and Boiling
Atmospheric pressure directly affects the boiling point of a liquid. Here is how:
At higher atmospheric pressure (e.g. at sea level), more energy (heat) is
required to make the vapor pressure of the liquid equal the atmospheric
pressure.
As a result, the boiling point increases.
At lower atmospheric pressure (e.g. at high altitudes), less energy is required
to match the vapor pressure with the reduced atmospheric pressure.
As a result, the boiling point decreases.

Boiling point of Water. The water always boils at 100°C but this is not
completely true. The boiling point of water varies at various locations. It
varies from 72°C to 101°C accordingly from the highest point to the
lowest point on land. The reason for these variations is the lowering of
atmospheric pressure as we travel to the highest point such as mountains
from lowest land point, i.e., Dead sea.

Water’s boiling point can differ at different
elevations. Place Elevation (m) Boiling point of water (o
C)
Mt. Everest Highest Mountatin 8,848 69.94
Kalimanjaro Highest Free Standing Mountain 5,895 80.33
La Paz Highest Capital City 3,640 87.71
London Capital City of United Kingdom 14 99.96
Sea Level Relative elevation reference 0 100.0
Baku World’s lowest capital city 28 100.1
The Dead Sea Lowest point in the world 427 101.4

Practical application:
Cooking at High Altitudes:
Water boils at lower temperature so food takes longer to cook
Pressure cookers:
Increase pressure to raise the boiling point,
allowing food to cook
faster.

Cooking with Salt
Addition of salt raises the water’s boiling point. This is an
example of boiling point elevation. The chemistry behind this is
that when salt, i.e., sodium chloride, is added to water, it
dissociates into sodium and chloride ions. These ions alter the
intermolecular forces between water molecules. The more salt
added, the boiling point rises. Colligative property depends on
the number of particles formed in the solution.

Sugar Refining
Sugar refining is often done in vacuum pans because vacuum
conditions provide several advantages:
• Lower boiling point. Under vacuum, the boiling point of the sugar
syrup is significantly reduced. This helps prevent caramelization or
degradation of sugar due to high temperatures, thus, preserving its
quality
• Energy efficiency. Boiling at lower temperatures requiress less
energy compared to boiling at atmospheric pressure, making the
process more energy-efficient

Sugar Refining
• Improved Crystal Formation. Lower temperture and controlled
evaporation create better conditions for the formation of uniform
sugar crystals. This ensure highly quality and consistency in the
final product.
• Reduced Coloration. High temperatures can cause sugar to darken
or form unwanted by-products. Operating under a vacuum
minimizes these risks, producing lighter-colored sugar

Sugar Refining
• Faster Evaporation. The vacuum enhances the rate of water
removal, speeding up the crystalization process and improving
productivity.
• Minimized Inversion. Sugar inversion (convertion of sucrose into
glucose and fructose) is reduced under low-temperature conditions,
which prevents losses and maintains the purity of sugar
By using vacuum pans, sugar manufacturers achived a high-quality
product effeciency and economically.

Boiling Milk
Water is a simple liquid, which does not contain any solids, whereas milk is a
compound, which contains fat in emulsion form, protein in a colloidal state,
and lactose as true solution.
When milk is heated, the fat, which is lighter than water, is collected on the
surface along with protein in form of cream, and when milk is overheated, the
water vapors expand, which builds up pressure and lifts the creamy layer up,
and eventually, milk spills out. When solute is also present with pure solvent
(here in case of milk, fats, proteins in milk act as a solute), the boiling point
of solution increases.

Application of Freezing Point Depression on Food Industry
Ice cream production:
• Adding sugar and other solutes to the mixture lowers the freezing point, allowing the ice cream to
freeze at temperature lower than 0o
C while maintaining the creamy texture.
• Salty (rock salt) is added to ice in the outer container of an ice cream maker to lower the freezing
point that can reach below 0o
C temperatures. This allows the ice cream mixture inside the
container to freeze at lower temperature than it would under normal condition. The salt dissolves
in the thin layer of water on the surface of the ice, creating a saltwater solution. This solutions has
lower freezing point than pure water, so it melts the ice to create a supercooled liquid. The heat
required to melt the ice is absorbed from the surroundings, including the ice cream mixture, cause
it to freeze

Milk Production
• Detection of Milk Adulteration. The freezing point of milk is reliable indicator of
its purity. Fresh, unadulterated milk has a freezing point slightly lower than water
(-0.525o
C to -0.549=0o
C). Adding water to milk raises its freezing point closer
to 0o
C which can be detected through freezing point.
• Ensuring Compliance with Standards. Different countries has different standard
• Quality Control in Dairy Processing. Freezing point depression is used to monitor
the consistency and composition of milk throughout the production process. It
helps verify if the milk’s properties are maintained during, processing, or
transporation.

Milk Production
• Formulation of Dairy Products. In the production of ice cream and other frozen
dairy products, freezing point depression is used to control the texture and
stability. Adding sugar, salt, and other solutes lower the freezing point, ensuring
a soft creamy texture rather than a hard, ice consistency.
• Monitoring Seasonal Variation in Milk. The freezing point of milk can slightly
vary due to natural changes in the composition of milk (e.g. fat, protein, lactose)
cause seasonal factor. Monitoring freezing points can help dairy processors
adjust formulation or processing parameters to maintain consistent product
quality

Application of Osmosis in Food Preservation
Osmotic pressure is defined as the pressure that must be applied to the solution side to
stop fluid movement when semipermeable membrane separates a solution from pure
water.
• Preservation with Salt and Sugar. High osmotic pressure caused solutes like salt
(curing) or sugar (in canned fruits) draws water out of microbial cells, preventing
spoilage
• Osmotic Dehydrtion. Foods like fruits soaked in concentrated sugar solutions to
reduce water content with applying heat, preserving flavor and nutrients.

In hypotonic solutions, there is a net
movement of water from the outside
solution into inside solution. In hypotonic
solution facilitates water absorption of
extraction from food products.
The following are some specific uses:

• Hydration of Dehydrated Products.
Hypotonic solutions are used to
rehydrate dried foods like fruits,
vegetables, or meat by allowing water
to move into the food cells, restoring
their original texture and apperance.

• Juiceness Enhancement. In processed
meats or fruits, hypotonic solutions
can be injected to enhance juiceness
and weight. It is commonly practice in
production of sausages, hams, and
canned fruits.

• Softening of Textures. Fruits and
vegetables can be softened using
hypotonic solutions to make more
palatable and easier to process (e.g.
peeling and cutting). This process is
often applied in the preparation of
jams, jellies, or juices.

• Flavor Infusion. Hypotonic solutions
containing flavors, seasoning, or
preservatives can be used to infuse
flavor into foods. The example of these
are fruits or meats are soaked in these
solutions for marination.

• Cell Rupture for Juice Extraction. By
creating a hypotonic environment,
water enters the cells, causing them to
swell and sometimes rupture, which
aids in juice extraction from fruits.

• Reduction of Solute Concentration.
Foods with high solute concentration
(e.g. , sugar or salt) can be
equilibrated with hypotonic solution to
dilute the solutes and achieve a desired
concentration.

• Desalination of Salted Food. Hypotonic
solutions can be used to reduce the
salt content in heavily salted foods like
dried fish, meats, or pickles by
facilitating the difusion of salt out of
the food.

• Washing and Cleaning. Hypotonic
solutions can remove surface
contaminants from fruits, vegatables,
and other foods by drawing them out
through osmosis.

The application of hypotonic solution in
food processing can enhance texture,
flavor, and functionality, but requires
careful management to maintain product
quality and safety

An isotonic solution is any external solution
that has the same solute concentration with
the inside concentration. In an isotonic
solution, no net movement of water will take
place.
The following are some key applications:

• Preservation and Osmotic Dehydration.
Isotonic solutions are used to control water
activity in food, helping to prevent
microbial growth. Food like fruits and
vegetables are immersed in isotonic sugar
of salt solution to facilititate osmotic
dehydration. This process removes water
without causing significant structural or
compositional changes.

• Brining and Marination. Isotonic salt
solutions are often used in brining meat
and seafood to improve moisture retention,
tenderness, and flavor. Example. Poultry
or fish immersed in brine absorbs
moisture, enhancing juiciness and shelf life.

• Cryoperservation of Foods. Isotonic
solutions help protect cellular structures
during freezing. When foods are frozen,
isotonic solutions prevent damage cause by
ice crystal formation within cells.
Example: Cryopreservation of fruits,
vegetables, or seafood.

• Beverage Formulation. Isotonic solutions
are used to develop sports drinks and
beverages that match the osmolarity of
body fluid. Example: Isotonic drinks for
althletes ensure rapid hydration and
nutrient absorption.

• Maintaining Cellular Integrity. In food
processing, isotonic solutions are used to
maintain the integrity of plant and animal
cells. Example Vegetables blanched in
isotonic solutions retain their firmness and
texture better than those blanched in pure
water.

• Food Texture Enhancement. Isotonic
solutions stabilize the texture of certain
foods during processing. Example: Pre-
soaking potatoes in isotonic solution
before frying ensure uniform cooking and
texture

Benefits of Using Isotonic Solution:
• Minimal Nutrient Loss. Isotonic solutions
help retain water-solutble nutrient during
osmotic process.
• Improved Flavor and Shelf-Life: Foods
treated with isotonic solutions have better
taste and longer preservation due to reduce
microbial growth.

Challenges of Using Isotonic Solution:
• Precise control of isotonicity is crucial to
avoid undesirable effects like excessive
dehydration of solute absorption.
Isotonic solutions play a vital role in ensuring
the quality, safety, and apperance of
processed foods.

A cell placed into a hypertonic solution will shrivel and die
by a process known as plasmolysis. Hypertonic solutions
help to preserve food. For example, packing food in salt or
pickling it in a hypertonic solution of sugar or salt creates a
hypertonic environment that either kills microbes or at least
limits their ability to reproduce.

Hypertonic solution are frequently used in food
preservation, flavor enhancement, and texture modification:
Here is how they are applied:
• Food Preservation
Dehydration and water Activity Reduction: A hypertomic
solution (e.g., concentrated salt or sugar solutions) drwas
water out of food and microorganisms through osmosis,
reducing water activity. This inhibity the growth and
spoilage and pathogenic organisms.

Example of this is salting of meat and fish (curing) and
sugaring fruits to preserve them.
Pickling: Foods like cucumbers, olives, and vegetables
immersed in brines (salt or acid solutions), creating
hypertonic environment that prevent microbial growth.
• Flavor Enhancement. Hypertonic solutions are used to
infuse flavors into foods. For instance brining poultry or
pork in a salty solution not only add flavor but also
increases juiceness.

Sugaring fruits enhances sweetness and preserves their
natural flavors.
• Texture Modification. Food soaked in hypertonic
solutions can experience changes in texture due to water
loss or solute absorption. Example: vegatables become
crisper in brine, while fruits soaked in sugar solutions
may become softer and juicier.

• Candy Making. Concentrated sugar solutions are
essential for creating candies. These solutions prevent
microbial growth due to their hypertonic nature and
contribute to the candy’s structure and shelf stability.
• Freeze-Drying Preparation. Foods may be pre-treated
with hypertonic solutions to remove moisture before
freeze-drying enhancing the efficiency of the process
and improving the final product’s texture and flavor.

• Healthier Food Options. Some low-sodium products use
hypertonic solutions with alternative salts or additives to
reduce overall sodium content while maintaining
preservation and flavor.
The application of hypertonic solutions is a critical
technique in extending shelf life, improving food quality,
and developing unique food products.

Osmosis is the movement of solvent particles (usually water) across a semipermeable
membrane from a dilute solution to a concentrated solution. The solvent dilutes the
concentrated solution until concentration is equalized on both sides of the membrane.
Diffusion is the movement of solvent and solute particles from an area of higher
concentration to lower concentration. At equilibrium, the net effect is a homogeneous
concentration throughout the medium.

1. Food Preservation:
• Pickling: Osmosis helps draw water out of fruits or vegetables when placed in a concentrated salt or
sugar solution, inhibiting microbial growth and preserving the food.
• Curing: In processes like meat curing, salt penetrates the tissue via osmosis, removing water and
preventing spoilage.
Application of Osmosis in
Food Processing

Application of Osmosis in Food Processing
2. Flavoring
• Marination: When foods are sooked in brines or marinades, osmosis aids in infusing
flavors into food while simultanesously removing moisture.
3. Dehydration. During osmotic dehydration, fruits and vegetables are immersed in hypertonic
solutions (e.g., sugar syrup), reducing water content while retaining nutrient.
4. Concentration of Juices. Osmosis is used in processes like reverse osmosis to concentrate
fruit juices by removing water without using heat, preserving flavor and nutrients.

Application of Diffusion in Food Processing
1 . Infusion of Flavors: Diffusion allows the movement of flavors (e.g., herbs or spices)
into liquid or solid foods during cooking or steeping, enhaning taste.
2 . Fermentation: In bread-making or
alcohol production, diffusion helps
apread gases (like CO2) and nutrients
throughout the medium, aiding
fermentation.

Application of Diffusion in Food Processing
3. Drying: Diffusion is a key process in drying foods, where moisture moves from the
interior to the surface before evaporating.
4. Blanching and Leaching: During blanching, diffusion helps remove unwanted
compounds (e.g., bitterness) from foods like vegetables. It is also used to reduce
sugar or salt content by soaking.
5 . Brining and Smoking: Diffusion aids in the penetration of salt, smoke, or curing
agents evenly into the food, enhancing flavor and preservation.
These processes leverage the natural movemen of water and solutes tp create
deirable food production, extends shelf-life, and improve sensory qualities.

The principle of osmosis is used to preserve jams, jellies and pickles. In this process,
water tends to draw out from microbes (plasmolysis) and makes it dehydrated, thus
killing them. But yeasts and moulds are relatively resistant to high osmotic pressure.
Hence, preserved foods like pickles tend to spoil if not stored properly.
High Concentration of Sugar
Jams and jellies prepared from fruits have a high concentration of sugar and it acts as a
preservative. Pectin, acid and sugar are essential to prepare jam. Jam or jelly are
prepared by adding commercially prepared pectin and it also reduces the cooking time.
Jellies are clear substances made of fruit juice or the extract of a fruit.

Sugar acts in the following ways:
Sugar draws the water out of food therefore making it unavailable for microorganisms. As a
result of water loss, microbial metabolism is stopped. Hence, the growth of microorganisms is
stopped.

Preparation of jelly:
• Under ripe fruits are used, because the pectin content is high and good acidity is essential for
a good jelly.
• Pieces of fruit are completely immersed in water and cooked for 10–20 minutes. Hard fruits
like guavas need to be cooked for 45 minutes.
• After the fruit is cooked, it is strained without disturbing the fruit pieces.
• The fruit extracts contain pectin which determines the addition of sugar. When the level of
pectin is high, it needs more sugar but requires less boiling time.
• Rapid boiling facilitates rapid evaporation, which avoids strong flavor and darkened colour.
• Then the jelly is poured in bottles or moulds, and allowed to set without any disturbance.

Preparation of jam:
• Fruits like apples are cooked with skin and made into pulp with the strainer for making jam
• Equal quantities of sugar and pulp are taken to make jam.
• After it is cooked, it is transferred to a sterilized bottle and allowed to cool.
Test for doneness for jam
• Sheet test – the mixture is allowed to drip from a large cool spoon. If the syrup forms a sheet
instead of two separate drops, the jam is done.
• Bubble test – when the end point reaches, big bubbles can be seen throughout the jam.
• Plate test – set a plate in the freezer for some time. Put the jam and tilt the plate slowly. The jam
should come down as a whole mass forming “U” shape. Water should not separate out.
• Fork test – dip the fork into the jam or jelly. Jam of correct consistency forms a sheet between the
needles of the fork.

Spices and condiments:
These have bacteriostatic effect (slowing the growth and multiplication of microbes). The
essential oil of spices is inhibitor of microorganism. The inhibitory effects of the spices differ
with the kind of spice and the microorganisms being tested. Mustard flour and the volatile oil
of mustard, for example, are very effective against Saccharomyces cerevisiae. In pickles like
chilli pickle, mustard flour helps in the prevention of the growth of spoilage organisms in the
food.
Turmeric powder, tamarind, chilli powder, cinnamon and cloves are usually bacterio-
static. Ground pepper corn and all spices are less inhibitory than cinnamon and cloves.
Extracts of these plants have been shown to be inhibitory to Bacillus subtilis and E. coli.
Allicin is the active principle in onions and garlic that kills bacteria and acts against fungi.

In addition to salt and several spices, oils are used in making pickles. Spice mixtures and oil are
added to the fruit or vegetable. It is allowed to ferment for a month or so. The fermentation
process renders fruits soft and the fruit take on the additional aroma and flavour of the spices.
Aerobic bacteria and mould growth are prevented by covering the top with oil. Properly
prepared and stored pickles can last upto a year or more without spoilage.

Application of Colloids in Food Industry
Food hydrocolloids are high molecular weight hydrophilic biopolymers used in food products
to control their texture, flavor and shelf life. Colloidal systems in foods can be classified into
different groups based on the states of matter constituting the two phases. They are sols, gels,
emulsion and foam. Emulsion and foam again can be categorized into solid emulsion/foam and
liquid emulsion/foam.

Colloids are formed when one substance is dispersed through another,
• sols (a solid is dispersed in a liquid)
• gels (a liquid held in a solid network, e.g., jam or jelly)
• emulsions (oily and watery liquids mixed together, e.g., milk and butter)
• foams (bubbles of gas trapped in a liquid, e.g., whisked egg white or whipped cream)
• solid foam (bubbles of gas trapped in a solid, e.g., meringue, cake, bread).
Most colloids are stable, but the two phases may separate over a period of time because of an
increase in temperature or by physical force. They may also become unstable when frozen or
heated, especially if they contain an emulsion of fat and water.

Functions of Colloidal Systems in Food Products:
Colloidal systems give structure; texture and mouth-feel to many different food products, for
example – Jam, ice cream, mayonnaise. Food colloid contains hydrocolloid (a substance that
yields a gel with water) that gives stability and rheological (the ability to flow or deformed)
properties of food components. An emulsifying agent may be used to help the oil and water
phases to mix permanently.

Types of Colloidal System in Food:
(i) Sols and Gels: A sol can be defined as a colloidal dispersion in which a solid is the
dispersed phase and liquid is the continuous phase. Gravy, stirred custard and other thick
sauces are some of the examples of sols. When a jelly is made, gelatin is dispersed into a liquid
and heated to form a sol. As the solution cools, protein molecules unwind forming a network
that traps water and forms a gel.

If corn flour is mixed with water and heated, the starch granules absorb water until they
rupture, the starch then disperses in the water and the mixture becomes more viscous and
forms a gel on cooling. Other types of gel are formed with pectin and agar. Pectin, a form of
carbohydrate found in fruits, is used in the production of jam to help it set.
However, for it to gel there must be at least 50% sugar and conditions should be acidic. Agar is
a polysaccharide extracted from seaweed which is capable of forming gels. If a gel is allowed to
stand for a time, it starts to ‘weep’ (to ooze out a fluid slowly). This loss of liquid is known as
syneresis (the separation og liquid from gel caused by contraction).

(ii) Emulsions: An emulsion is a mixture of two or more immiscible (they will not mix together)
liquids. One liquid (the dispersed phase) is dispersed in the other (the continuous phase), i.e.,
material that keep fat globules in water droplet or water droplet in fat are emulsifiers. When
water and oil are shaken together, they form an emulsion. This emulsion is unstable.
If left to stand, the oil will form a separate layer on top of the water, e.g., traditional French
dressing. A stable emulsion is formed when two immiscible liquids are held stable by a third
substance, called an emulsifying agent. An emulsion may be oil-in-water (o/w) in which case
small oil droplets are dispersed through water, e.g., milk, or water-in-oil (w/o) in which case
small water droplets are dispersed through oil, e.g., butter.

(iii) Foams: Foams are composed of small bubbles of gas (usually air) dispersed in a liquid,
e.g., egg white foam. As liquid egg white is whisked, air bubbles are incorporated. The
mechanical action causes albumen proteins to unfold and form a network, trapping the air. If
egg white is heated, protein coagulates and moisture is driven off. This forms solid foam, e.g., a
meringue. Ice cream, bread and cake are other examples of solid foams.

Stability of Colloidal Systems:
All colloidal systems have two phases a continuous phase and discontinuous or
dispersed phase. The particles of the dispersed substance are suspended in the mixture
and do not completely dissolved within. The substance which is dispersed is known as
the disperse phase and is suspended in the continuous phase. Most colloids are stable.
The stability depends on the interaction between the two phases. But the two phases
may separate over a period of time because of an increase in the temperature or by
physical force.

Stability of Sols and Gel in Food:
A sol is a colloidal system in which a solid is dispersed phase and liquid is the continuous phase.
The proper ratio of the ingredients is necessary to achieve the desired viscosity of the sols at a
certain temperature. Pectin is hydrophilic and attracts a layer of water that is bound tightly to
the molecules by hydrogen bonds. So water forms an insulating shield for the pectin providing
layers that inhibit bonding between the molecules of the colloidal substances.
Sols can be transformed into gels as a result of reduction in temperature. In pectin gel, the pectin
molecules are the continuous phase and the liquid is the dispersed phase while in pectin sol, the
pectin molecules are the dispersed phase and the liquid is continuous phase. Sols may be formed
as a preliminary step in making a gel. Jams and jellies made with pectin are common examples
that form a sol prior to the desired structure.

Stability of Emulsion in Food:
An emulsion is a mixture of two or more immiscible (they will not mix together) liquids. One
liquid (the dispersed phase) is dispersed in the other (the continuous phase), i.e., material that
keep fat globules in water droplet or water droplet in fat are emulsifiers. An emulsion may be
oil-in-water (o/w) in which case small oil droplets are dispersed through water, e.g., milk, or
water-in-oil (w/o) in which case small water droplets are dispersed through oil, e.g., butter.
An emulsifying agent is made up of two parts. One is hydrophilic (water loving) and the other is
hydrophobic (water hating). The emulsifier holds the disperse phase within the continuous
phase. This results in the emulsion becoming stable.

Mayonnaise is an example of a stable emulsion of oil and vinegar, when egg yolk (lecithin) may
be used as an emulsifying agent. Stabilizers are often added to emulsions to increase the
viscosity of the product. These help improve the stability of the emulsion, as over time the
emulsion may separate. Stabilisers also increase shelf life, E461 methylcellulose, used in low
fats spreads.

References
• Food Preservation Methods , 11th Home Science : Chapter 4 : Food Preservation Methods
• Glater, J. (1998). “The early history of reverse osmosis membrane development.” Desalination. 117
(1–3): 297–309. doi:10.1016/S0011-9164(98)00122-2
• Haynie, Donald T. (2001). Biological Thermodynamics. Cambridge: Cambridge University Press.
pp. 130–136. ISBN 978-0-521-79549-4.
• Kramer, Eric; David Myers (2012). “Five popular misconceptions of osmosis.” American Journal of
Physics. 80 (694): 694–699. doi:10.1119/1.4722325
• Landau, L.D.; Lifshitz, E.M. (1980). Statistical Physics (3rd ed). Vol. 5. Butterworth-Heinemann.
ISBN 978-0-7506-3372-7.
• Muir, D. C. F. (1966). “Bulk flow and diffusion in the airways of the lung.” British Journal of
Diseases of the Chest. 60 (4): 169–176. doi:10.1016/S0007-0971(66)80044-X
• Colloidal Systems in Food: Functions, Types and Stability | Food Chemistry.
ttps://www.biotechnologynotes.com/food-biotechnology/food-chemistry/colloidal-systems-in-
food-functions-types-and-stability-food-chemistry/14096
• Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail
11th Home Science : Chapter 4 : Food Preservation Methods : Preservation by High Osmotic
Pressure | Food Preservation Methods

5.-Application-of-Colligative-Properties-to-Food-Processing.pptx

5.-Application-of-Colligative-Properties-to-Food-Processing.pptx

More Related Content

Similar to 5.-Application-of-Colligative-Properties-to-Food-Processing.pptx

More from albenidictmoreno

Recently uploaded

5.-Application-of-Colligative-Properties-to-Food-Processing.pptx

Editor's Notes