The document discusses water and its uses in food. It defines water as H2O, describing its unique properties including existing in three states, hydrogen bonding, and role in biological processes. Water exists in foods in free, absorbed, and bound forms, with bound water inversely related to water activity (Aw). Aw measures available water and is important for microbial growth. The document outlines water's various uses in food production from farming to processing. Overall, water plays critical roles in food textures, reactions, and microbial support.

1. Student’s name :Tran Thi Thu
ID: BTFTIU15072
Submitted to : Dr. Nguyen Van Toan(PhD)

3. I/ Organic acid.
1. Definition.
2. Some common organic acids.
II/ Usage in food product development.
III/ Summary.
IV/ References.

4.  1/ Definition :
- An organic acid is an organic compound
with acidic properties.
- The most common organic acids are
the carboxylic acids, whose acidity is
associated with their carboxyl group –COOH.
- For example: CH3COOH, C2H5COOH,...

5.  Organic acids have acidic properties. For
instance, acids have a pH value of less than 7
(turn blue litmus paper red).
 Sour in taste (i.e., lemons)
 Organic acids are commonly weak acids
because they partially ionize in solution.

6.  Citric acid: Citric acid is a natural, weak
organic acid that is found in many fruits and
vegetables, especially citrus.

7.  Malic acid: Malic acid is an organic compound
that is naturally found in fruits such as
apples.

8.  Tartaric acid: is founded in several plants,
fruits and vegetables including bananas and
grapes. Several of its salts occur during the
fermentation of grapes to form wine.

9.  Lactic acid: is an organic compound with the
formula CH3CH(OH)COOH. In its solid state, it
is white and water-soluble. In its liquid state,
it is colorless. It is produced both naturally
and synthetically.

10.  Acetic acid : (ethanoic acid) is a colourless
liquid organic compound with the chemical
formula CH3COOH
 Acetic acid has a distinctive sour taste
 Acetic acid is the second simplest carboxylic
acid (after formic acid).

11.  1/ Uses for Citric Acid in Food
- Approximately 50% of the world’s citric acid
production is used as a flavor enhancer in
beverages.
- Citric acid is used in soft drinks, teas, juices,
and other beverages to create a slightly tart,
refreshing flavor and balance sweetness.

12.  1/ Uses for Citric Acid in Food
- The acidic pH of citric acid also makes it
useful as a preservative.
- It can be used in dry foods when a sour
flavor is desired.
=> For these reasons, citric acid is found on
the ingredient list of many food products today.

13.  2/ Uses for Malic acid in Food :
The malic acid in food provides a range of
benefits as follows:
-It supports the body in the release of energy
from food;
-It increases physical endurance of athletes and
sportsmen;

14.  2/ Uses for Malic acid in Food:
-It provides valuable support during the
hypoxic phase of training;
-It can relieve the symptoms of chronic
fibromyalgia reducing pain.
=> For the reasons above, the consumption
of food containing malic acid is highly
recommended for people who practice sports at
intense, competitive or professional level.

15.  2/ Uses for Malic acid in Food: Application
- Carbonated Beverages
Adding Malic Acid improves economies,
especially in artificially sweetened products.
Flavors are enhanced, allowing the use of less
flavor additives, and the overall flavor profile is
broader and more natural.
- Powdered Mixes
In iced tea, sports drink or fruit soup dry mixes,
Malic Acid is preferred due to its rapid dissolution
rate and flavor enhancement qualities.

16.  2/ Uses for Malic acid in Food: Application
- Hard Candy
Malic Acid boosts sourness intensity and
enhances fruit flavors.
- Chewing Gum
Organic food acids help improve saliva
stimulation in chewing gum. Malic Acid is
preferred due to its flavor enhancement
properties.

17.  3/ Uses for Tartaric acid in Food:
- It has many applications in the food industry
due to its sour taste and antioxidant properties.
- It is widely used in carbonated drinks,
effervescent tablets, sour candies, gelatins,
jellies, baking powders, and taffies. It also has
many industrial uses such as in photographic
printing and development, polishing metals,
wool dyeing, etc. The tartrate salts are used in
silvering mirrors, cleaning brass, dyeing
mordant, and as insecticide.

18.  4/ Uses for Acetic acid in Food:
- It is produced industrially both synthetically
and by bacterial fermentation. About 75% of
acetic acid made for use in the chemical
industry is made by the carbonylation of
methanol. In this process, methanol and carbon
monoxide react to produce acetic acid
according to the equation: 2 CH3CHO + o2 -> 2
CH3COOH

19.  4/ Uses for Acetic acid in Food:
- The fermentation accounts for only about 10%
of world production, but it remains important
for the production of vinegar, as many food
purity laws stipulate that vinegar used in foods ,
must be of biological origin.

20.  5/ Uses for Lactic acid in Food:
- Lactic acid is naturally present in many
foodstuffs. It is formed by natural fermentation
in products such as cheese, yogurt, soy sauce,
sourdough, meat products and pickled
vegetables.

21.  5/ Uses for Lactic acid in Food:
-Beverages
Because of its mild taste, lactic acid is used as an acidity
regulator in beverages such as soft drinks and fruit
juices.
- Pickled vegetables
Lactic acid is effective in preventing the spoilage of
olives and other vegetables preserved in brine.
- Dairy
The natural presence of lactic acid in dairy products,
combined with the dairy flavor and good antimicrobial
action of lactic acid, makes lactic acid an excellent
acidification agent for many dairy products.

22.  Organic acid is an organic compound
with acidic properties which characterized by
carboxylic acid group (RCOOH).
 Generally, organic acids are very common in
foods. Such as citric acid from lemon, lactic
acid from yogurt,…
 Organic acid have many application in food
especially in food preservation and flavor
food.

23.  http://study.com/academy/lesson/organic-
acids-properties-production-examples.html
 https://www.thespruce.com/what-is-citric-
acid-1328465
 http://www.polynt.com/en/malic-acid-in-
food/
 http://www.softschools.com/formulas/chemi
stry/tartaric_acid/332/

25. I/ Water.
II/ Water in food.
III/ Using water in food production.
IV/ Summary.
V/ References.

26.  WHAT IS WATER?
- Water is a chemical compound. Each molecule
of water, H2O or HOH, consists of two atoms of
hydrogen bonded to one atom of oxygen.
- Water contains intermolecular polar covalent
bonds.
- Pure water has a neutral pH. Pure water has a
pH, of about 7, which is neither acidic nor
basic.

27. - Water is unique in that it is the only natural
substance that is found in all three states --
liquid, solid (ice), and gas (steam). Earth's
water is constantly interacting, changing, and
in movement.
- Water's freezing and boiling points are the
baseline with which temperature is measured:
0° on the Celsius scale is water's freezing
point, and 100° is water's boiling point. Water
is unusual in that the solid form, ice, is less
dense than the liquid form, which is why ice
floats.
- Water has a very high surface tension.

28. - Water has hydrogen bond. Under certain
conditions, an atom of hydrogen is attracted
by rather strong forces to two atoms instead
of only one, so that it may be considered to
be acting as a bond between them. This is
called hydrogen bond

29. - When the water molecule makes a physical phase
change its molecules arrange themselves in
distinctly different patterns (Figure below). The
molecular arrangement taken by ice (the solid form
of the water molecule) leads to an increase in
volume and a decrease in density. Expansion of the
water molecule at freezing allows ice to float on
top of liquid water.

30. - The three diagrams above illustrate the distinct arrangement patterns
of water molecules as they change their physical state from ice to water
to gas. Frozen water molecules arrange themselves in a particular
highly organized rigid geometric pattern that causes the mass of water
to expand and to decrease in density. The diagram above shows a slice
through a mass of ice that is one molecule wide. In the liquid phase,
water molecules arrange themselves into small groups of joined
particles. The fact that these arrangements are small allows liquid
water to move and flow. Water molecules in the form of a gas are
highly charged with energy. This high energy state causes the
molecules to be always moving reducing the likelihood of bonds
between individual molecules from forming.

31. - Water is a very common substance existing freely in
nature, although access to it can be difficult in many
communities in the world. It is believed that more than
70% of the earth’s surface is made up of water.
- Water is an essential constituent of any foods.
- It may occur as:
+ An intracellular or extracellular component in vegetable
and animal products.
+ As a dispersing medium or solvent in many foods and
as the dispersed phase in some emulsified products such
as butter, margarine.
+ As a minor constituent in some foods.

32. - The body needs water to regulate its temperatures.
It also uses it a medium for blood development.
Water is needed for the transport of hormones,
nutrients and sugar to all part of the body cells.
Water is needed for lubrication of joints. Also
importantly, it carries all the by-products of
digestion, together with toxic compounds from the
body and passes them out in the form of urine.

34.  Water exists in 3 forms in foods
- Free water
- Absorbed water
- Bound water
Chemically, each form of water is the same (H2O),
but differences exist in the physical and chemical
conditions in which water can exist.
The form in which water occurs in foods
determines the physical properties of the food.
 For e.g. Fluid milk and apples contain
approximately the same amount of water but have
different physical structures.

35.  Free water:
+ Most water in foods is called free water.
+ Free water is lightly entrapped and therefore
easily pressed from food.
+ It acts as a dispersing agent and solvent and
can be removed by drying foods
 Absorbed water:
 + This water associates in layer through
intermolecular hydrogen bonds around
hydrophilic food molecules.

36.  Bound water:
+ Bound water is the water that remains
unfrozen at temperature below 0°C usually
-20°C
+ Also ti is the amount of water in a food that
is unavailable as a solvent.
+ The amount of unfreezable water, based on
protein content, vary from one food to another.

37.  The presence of water in food is describled as
the moisture content or water activity (Aw) of
the food.
 Moisture refers to the amount of water
present in food while water activity (Aw)
refers to the form in which water exist in the
food.

38.  Water activity is the measure of the
availability of water molecule to enter into
microbial, enzymatic or chemical reactions,
through a number known as water activity
(AW).
 Water activity is a measure of the amount of
free and adsorbed water in food, and is
measured on a dimensionless scale of zero to
one.
 Regarding the forms of water, bound water is
inversely related to water activity.
 As the % of bound water in a food increases
the Aw decreases.

39.  Water activity is the ratio of the vapor
pressure (P) of water in food divided by the
vapor pressure of pure water (P0) at the same
temperature.
aw =
𝑃
𝑃𝑜
 Vapour pressure can be measured by using a
manometer
 The water activity of pure water is equal to
1.0.

40.  Some foods are stable at low moisture
content where es others are stable at relatively
high moisture content.

41.  Some kind of food that form water:

42.  Our cells get the needed moisture from the
water that we drink. Many fruits such as
oranges, watermelon, grapes and apples
contain water. Vegetables such as
cucumber, tomatoes, and fresh salads
contain water too. Digestion of solid foods
also result in the release of water in our
bodies

43.  Water is routinely used in food production as
an ingredient, for cleaning, sanitation and
manufacturing purposes. This article
discusses the sources, treatments and uses of
water by food businesses, and the importance
of maintaining a safe water supply to ensure
production of safe and quality foods.

44.  There are four broad uses of water in food
production:
 Primary production (e.g. farming),
 Cleaning and sanitation,
 As an ingredient or component of an
ingredient,
 Processing operations (e.g. heating,
refrigeration).

45.  Water is essential compound which is present
in most natural food.
 Water plays many very important roles in
food. It affects texture (dry and brittle
versus moist and soft), enables the activity
of enzymes and chemical reactions to occur
(acts as a solvent), supports the growth of
microorganisms, makes it possible for large
molecules like polysaccharides and proteins
to move about and interact, and conducts
heat within food.

46. - http://imnh.isu.edu/digitalatlas/hydr/basics/
main/chmtxt.htm
- http://www.cookingscienceguy.com/pages/w
p-content/uploads/2012/07/What-Is-So-
Special-About-Water-In-Food.pdf
- http://www.eufic.org/en/food-
production/article/use-of-water-in-food-
production
- https://www.courses.psu.edu/fd_sc/fd_sc40
0_jnc3/water/2%20-Water.pdf