Ice cream is a sweetened frozen food typically eaten as a snack or dessert. It is usually made from dairy products, such as milk and cream, and often combined with fruits or other ingredients and flavors. It is typically sweetened with sugar or sugar substitutes. Typically, flavourings and colourings are added in addition to stabilizers. The mixture is stirred to incorporate air spaces and cooled below the freezing point of water to prevent detectable ice crystals from forming. The result is a smooth, semi-solid foam that is solid at very low temperatures (< 2 °C or 35 °F). It becomes more malleable as its temperature increases. The meaning of the phrase "ice cream" varies from one country to another. Phrases such as "frozen custard", "frozen yogurt", "sorbet", "gelato" and others are used to distinguish different varieties and styles. In some countries, such as the United States, the phrase "ice cream" applies only to a specific variety, and most governments regulate the commercial use of the various terms according to the relative quantities of the main ingredients, notably the amount of cream. Products that do not meet the criteria to be called ice cream are labelled "frozen dairy dessert" instead. In other countries, such as Italy and Argentina, one word is used for all variants. Analogues made from dairy alternatives, such as goat's or sheep's milk, or milk substitutes, are available for those who are lactose intolerant, allergic to dairy protein, or vegan. Ice cream may be served in dishes, for eating with a spoon, or in cones, which are licked. Ice cream may be served with other desserts, such as apple pie. Ice cream is used to prepare other desserts, including ice cream floats, sundaes, milkshakes, ice cream cakes and even baked items, such as Baked Alaska.

1. BUNDELKHAND UNIVERSITY
PRESENTATIONPRESENTATION
SUBJECT - DAIRY TECHNOLOGY
PRESENTATIONPRESENTATION

3. INTRODUCTION
 Origins in Europe
 In 1851 first wholesale ice cream industry in the US States
was established in Baltimore, Maryland.
 Evolved from iced beverages and water ices
 U.S. residents consume 1.5 billion gallons of ice cream U.S. residents consume 1.5 billion gallons of ice cream
each year; that’s roughly 5 gallons (19 liters) per person!

4. HistoryHistory
The history of ice cream is closely associated with the
development of refrigeration techniques and can thus
be traced in several stages:
Cooling food and drink it after mixing it with snow or ice.
Dissolving salts in water produces cooling.Dissolving salts in water produces cooling.
Mixing salts and snow or ice cools even further -in mid to late
17th century, the inclusion of cream in the water ices also
evolved around this time.
The invention of the ice cream maker in the mid 19th century

5. DEFINITIONDEFINITION
Ice cream is a frozen dairy product made by suitable
blending and processing of cream and other milk
products, together with sugar and flavour, with or
without stabilizer or colour, and with the
incorporation of air during the freezing process.
.
incorporation of air during the freezing process.
Ice cream is a dairy based product which typically
contains 6-12% fat, 7.5-11.5% non-fat milk solids and
13-18% sugars. Stabilizers, emulsifiers colours and
flavours are also added.

6. Requirement Ice Cream Medium Fat Ice
Cream
Low Fat Ice Cream
Total Solid Not less than 36.0
percent
Not less than 30.0
percent
Not less than 26.0
percent
Wt/Vol (g/l) Not less than 525 Not less than 475 Not less than 475
Table - FSSAI Standards for Ice cream
Milk Fat Not less than 10.0
percent
More than 2.5
percent but
less than 10.0
percent
Not more than 2.5
percent
Milk Protein
(Nx6.38)
Not less than 3.5
percent
Not less than 3.5
percent
Not less than 3.0
percent

7. Consumption/Production of Ice CreamConsumption/Production of Ice Cream
The ice-cream market in india is estimated at approximately $450 million in
2009-10.Growing at approximately 12-15 percent, it is expected to cross $900
million by 2014-15. The branded market is estimated at approximately $200
million and is growing at 20-25 per cent.
India has the right climate for ice cream consumption but has A very low per
capita consumption, which is approximately 300 ml per annum as against thecapita consumption, which is approximately 300 ml per annum as against the
world average of 2.3 liters per annum .
India is the fastest growing ice-cream consumption market in the world
followed by Vietnam and Indonesia. India's ice-cream market has registered a
compounded annual growth rate of 13 per cent in the last five years, In 2017,
volume sales in India are set to overtake those of more established markets,
including the UK. Ice cream sales in India, according to the report, is expected
to reach 381.8 million liters in 2017 and as much as 657.2 million liters in
2021.

8. Nutritive value
Contains two to three times as much fat and slightly more protein than
does milk.
In addition –other food products such as fruits, nuts ,eggs, and sugar
which enhance its food value.
Rich source of calcium ,phosphorus and other minerals
The protein contain is also rate high , both quantity and quality.
The milk and egg protein are complete protein ;they contains allThe milk and egg protein are complete protein ;they contains all
essential amino acid .
Especially important source of tryptophan and lysine .
Excellent source of food energy.
Excellent source of fat soluble vitamin A, a good source of thiamine,
riboflavin and niacin
The digestibility and palatability of ice-cream is also very high.

9. PLAIN ICE CREAM
Classification
Depending upon the commercial practices followed, the following
classifications are used for different groups of ice cream and frozen products.
An ice cream in which the total amount of the colour
and flavouring ingredients is less than 5% of the volume
of the unfrozen ice cream.
Examples are vanilla, coffee, maple and caramel ice
cream.

10. CHOCOLATE ICE CREAM
Ice cream flavoured with cocoa or chocolate

11. FRUIT ICE CREAM
Ice cream containing fruits with or without
additional fruit flavouring or colour such as
Strawberry , Apricot , Pineapple , Mango , Banana
etc

12. NUT ICE CREAM
Ice cream containing nut , such as almonds,
pistachio or walnut, with or without additional
flavouring or color.

13. ICE MILK / MILK ICE
A product similar to ice cream containing 2 -7% fats and 12-15%
MSNF, sweetened, flavoured and frozen like ice cream.
ICE MILK / MILK ICE

14. ICES ICE CREAM
Made of fruit juices, sugar and stabilizer with or without additional fruits, color,
flavouring or water and frozen to the consistency of ice cream. Usually contains 28 – 30%
sugar, 15-20% overrun, and no dairy products.

15. SHERBETS ICE CREAM
Sherbet is a product made of fruit juices, sugar, stabilizer, and milk products.
It is similar to an ice, except milk either whole, skim, condensed, or powdered,
ice cream mix, is used in place of all or part of the water used in ices, sherbet
contains 1% to 2% milk fat.

16. SOFT ICE CREAM (SOFTY)
Soft serve ice cream is a type of frozen dessert that is similar to,
but softer than the ice cream. these products are sold as drawn from the freezer without
hardening. It is generally lower in milk fat (3.6%) than ice cream (10-18%) and produced
at a temperature of about -4°C compared to ice cream, which is stored at -15°C.

17. FANCIFUL- ICE CREAM
These products usually do not contain a single characterizing
flavour, but the flavour is due to the mixture of several flavouring ingredients.
Two or more distinct flavours are present in the same package.

18. BISQUE ICE-CREAM
It is made by the addition of grape, nuts, macaroons, sponge cake or other
bakery products with appropriate flavourings.

19. CHEMISTRY of ICECHEMISTRY of ICE--CREAMCREAM
COMPOSITIONCOMPOSITIONCOMPOSITIONCOMPOSITION
• Fat - 10 to 16 %
• Milk solid not fat- 9 to 12 %
• Sweeteners- 12 to 16%
• Stabilizers and Emulsifiers- 0.2 to 0.5 %
• Water- 55 to 65 %

20. Ice Cream StructureIce Cream Structure
ICE CRYSTALS
AIR CELL
FAT GLOBULES
GLYCCEROLEROL
ICE CRYSTALS FAT GLOBULES
LIQUID SYRUP

21. PHYSICOPHYSICO--CHEMICAL PROPERTIES OF ICE CREAM MIXESCHEMICAL PROPERTIES OF ICE CREAM MIXES
MIX STABILITY -Fat globules size 0.5 – 1.0 μ and a maximum size of about 2 μ)
DENSITY OF MIXES - Density of mix may vary from 1.0554 to 1.1232 g/ml,
Dependent on the concentration of soluble constituents and
varies with composition
DENSITY OF MIXES - Density of mix may vary from 1.0554 to 1.1232 g/ml,
with an average for a 10% fat mix of approximately 1.1 g/ml.
ACIDITY OF MIXES-
• The normal pH of ice cream mix is about 6.3.
• An increase in MSNF raises acidity and lowers pH
• Normal titratable acidity of 0.187% lactic acid

22. MIX VISCOSITY-
• The resistance of a liquid to flow
• If viscosity is constant, regardless of the applied stress(liquid is said to be
newtonian )
• As the shear rate increases, the viscosity decreases.
• Affected by temperature
• The viscosities at 80°C ranges from 8.7centipoise (cp) in an unstabilized mix to
103 cp in mix containing 0.25% carboxy methyl cellulose
PHYSICO-CHEMICAL PROPERTIES OF ICE CREAM MIXES
103 cp in mix containing 0.25% carboxy methyl cellulose
FREEZING POINT-
•Dependent on the concentration of soluble constituents and varies with
composition
• Freezing point of approximately –2.5°c.

23. Typical freezing curve and freezing point of ice cream mix
Where
A= Temperature of aged ice cream mix
B= Super cooling of ice cream mix in the freezer
C= Actual freezing point of ice cream mix
D= Lowering of freezing point of ice cream mix
E= Eutectic point at which salts starts to crystallize out along with conversion of water in
to ice crystals
F= Eutectic point of another salt in the ice cream mix
G= Further freezing of water in ice cream mix

24. BASIC CONCEPTS RELATED TO FREEZING POINT OF ICE
CREAM MIX
Freezing point (FP) of ice cream mix varies appreciably with
composition.
The mix constituents that affect FP directly are:
• Sugar• Sugar
• Lactose
• Milk salts
• Any other substances that may have been added and that
are in true solution.

25. Ice Cream IngredientsIce Cream Ingredients
Dairy Products Non Dairy Products
SW E E TN IN G A GE NT
 FAT
 MS NF
SW E E TN IN G A GE NT
STA B ILIZE RS
E M UL S IF IE RS

26. FATS
Increase the richness of the ice cream flavour
Produce a smooth texture and give ‘body’
Produce good melting properties when the ice cream is eaten
Makes up about 10-15% of an ice cream mix
Relatively high cost and smoothness of textureRelatively high cost and smoothness of texture
May limit consumption due to high calories and satiating effect
Whole Milk, Cream, Anhydrous Milk Fat (AMF), Butter / butter oil
Vegetable fat –Palm oil,Palm kernel oil,Coconut oil.

27. MILK SOLIDSMILK SOLIDS--NOTNOT--FAT (MSNF)FAT (MSNF)
MSNF –proteins(casein and whey proteins), lactose and mineral
salts
Improves body and texture (protein) through emulsification and
water holding capacity
Promotes development of overrun
High amount may cause cooked or salty flavorHigh amount may cause cooked or salty flavor
Potential for sandiness (lactose crystallization) at high
concentration
Skim milk powder, Whey protein concentrate,Whey
powder,Lactose powder

28. SWEETENERSSWEETENERS
Depresses freezing point
Improve the pleasing creamy flavour, smooth texture and
palatability
Increase the acceptance of the product
Increases the viscosity and TS content of mix
Improves the body and texture.Improves the body and texture.
Also reduce the ‘fattiness’ of ice cream
Nonnutritive sweeteners - sucralose, aspartame, saccharin,
cyclamates, acesulfame -K
0.07% aspartame can provide the sweetness equivalent to 15%
sucrose.
Sucrose (cane or beet), fructose, Glucose, Galactose, Maltose,
Rhamnose, Lactose

29. STABILIZERSSTABILIZERS
Stabilizers are a group of compounds -(usually polysaccharides
such as guar, locust bean gum, carboxymethyl cellulose, and
xanthan)
Reduce the amount of free water in the mix by binding it as
“water of hydration”
The ability of stabilizer to absorb and hold large amounts ofThe ability of stabilizer to absorb and hold large amounts of
bound water
Produces good body, smooth texture,provide uniformity to the
product and resistance to melting
Increase the viscosity of the mix
Gelatin, Guar Gum, Sodium alginate, Carboxy methyl cellulose,
Pectin, calcium sulfate, modified starches, etc.

30. To help in suspension of flavouring particles
To reduce or slow down the growth of lactose crystals
during storage mainly during temperature fluctuations
To help prevent shrinkage of the product volume
during storage
STABILIZERSSTABILIZERS
during storage
To produce smoothness in texture during consumption
Facilitate the controlled incorporation of air in the
freezer

31.  Sodium Alginate (E401) –
• Is a polysaccharide of guluronic acid and mannuronic acid
• Extracted from brown seaweeds such as macro cystis pyrifera and
laminaria digitata
• Usually, it is used at a level of 0.18-0.25%.
 Guar gum (E412) –
• Extracted from the seeds of cyampo sistetra gonolobus
 Pectin (E440) – Pectin (E440) –
• Extracted from citrus peel and apple pomace
• It is a polysaccharide consisting of linear chains of galacturonic acid
and galacturonic acid methyl ester units
• Also used for setting agent
 Gelatin –
• Derived from collagen from animal connective tissues
• It is used at the rate of 0.2-0.3% and requires ageing for at least 4
hours

32. EMULSIFIEREMULSIFIER
Surface-active agents
Consists of a water-loving hydrophilic head and an oil-loving hydrophobic
tail(two domains)
A substance that reduces surface tension between oil–water or air water
interface,
Thus enhancing emulsification and increasing emulsion stabilityThus enhancing emulsification and increasing emulsion stability
Improve whipping quality of ice cream mix
Produce a dry and stiff ice cream
Used to improve whipping quality of the mix
Promote nucleation of fat during aging, thus reducing aging time.
Improved air cell distribution
Improved heat shock resistance

33. - They act to reduce the interfacial tension or
the force which exists between
the two phases of the emulsion.
- This causes a desorption of protein
from the fat droplet surface, which
promotes a destabilization of the
fat emulsion (due to a weaker
membrane) leading to a smooth,
dry product with good
meltdown propertiesmeltdown properties
(see diagram on the right).
Examples – Hydrophobic;- Sorbitan esters, - and diglycerides of fatty
acids, polyglycerol polyricinoleate, polyglycerol esters, and
propylene glycol esters.
Hydrophilic : Ethoxylatedsorbitan esters, monoglyceride derivatives such
as lactates, tartarates,citrates, low-substituted polyglycerol
esters, and monosubstituted sugaresters

34. FLAVOURFLAVOUR
Synthetic and natural flavours are used
Increases acceptability
Intensities and harshness may be unacceptable
Vanilla, chocolate
Dry ingredients:- chocolate , nuts, dried fruit pieces, candies, cookies, Smarties,Dry ingredients:- chocolate , nuts, dried fruit pieces, candies, cookies, Smarties,
caramel pieces, etc
Natural flvourings: Non-citrus fruit, citrus fruit,tropical fruit, natural flavours
from botanicals, spices, cocoa and chocolate,coffee, natural
flavourings from vanilla beans and nuts.
Liqueur flavourings: Alcohol, whiskey and other distilled beverages, fruit
brandy distillate and brandy flavour essence and fruit liqueurs

35. ColoursColours
Colour’s :-color are matched with the flavours added (it may be natural or
artificial )
Improves attractiveness flavore identification
Also synthetic or natural colour’s are added
Artificial shades Allergic reactions of some people
ColoursColours

36. OTHER INGREDIENTSOTHER INGREDIENTS
Dry ingredients - chocolate, nuts, dried fruit
pieces, candies, cookies, Smarties, caramel
pieces, etc.

37. ManufacturingManufacturing ofof Ice CreamIce CreamManufacturingManufacturing ofof Ice CreamIce Cream

38. Flow diagram for ice cream processingFlow diagram for ice cream processing
RAW MILK
FILTRATION
SEPARATIONSEPARATION
BUFFER CREAM STORAGE TANK

39. DRY FRUITS
CRUSTED
METAL DETECTOR
DRYING ( Hot Air Oven )
Ready to using for garnishing

40. CREAM (from buffer tank)
PRE HEAT
MIXING TANK
DRY INGREDIENT (Sugar, Stabilizer
emulsifier )
MIX HEATING at 60-70°C
VENILLA
COCA POWDER
VENILLA
COCA POWDER
WHIET ICE CREAM CHOCOLATE ICE CREAM
PASTURIZATION
HOMOGENIZATION
AGEING (4-6 HOURS at 5°C)

41. Control room / Production lineControl room / Production line
FMT ( FLAVOUR MIXING TANK )
CONTINUOUS FREEZING SYSTEM
FILLING
HARDNING at -35°cHARDNING at -35°c
PACKAGING
METAL DETEACTOR
STORAGE at -25 °C

42. Selection of ingredientsSelection of ingredients
Good quality materials are essential if the resultant product need to be
satisfactory in all aspects. The raw ingredients necessary to provide the
components of ice cream must contain sufficient fat and milk solids in
proportions that can be combined to make a mix of the desired composition
Selection of ingredients depends on theirSelection of ingredients depends on their
Availability
Perishability
Convenience in handling
Effect on flavour, body and texture of ice cream
Cost
Equipments available etc.

43. MAKING / BLENDING THE MIXMAKING / BLENDING THE MIX
The ingredients to be blended are taken in a vat, where it can be heated to
facilitate dissolving, blending.
Mixing process varies from a small batch operation type to a large scale
automatic continuous type depending upon the amount of mix to be
processed.
Liquid ingredients are mixed together and heated to 49°C prior to theLiquid ingredients are mixed together and heated to 49°C prior to the
addition of all dry ingredients.
Sodium alginate is mixed with a portion of sugar and slowly added to the
liquid maintained at 71.1°C at a moving agitator point.
When gelatin is used, it should be dissolved in nine times water by weight
with equal volumes of sugar before the liquid temperature reaches 49°C.
If butter, plastic cream, frozen cream or other frozen products are used,
they should be cut into small pieces and allowed for complete melting
before pasteurization.

44. PASTEURIZATIONPASTEURIZATION
Destroy all the pathogenic bacteria in the mix so as to render the final
product safe for human consumption.
Most hydrolytic enzymes, even the natural ones of raw milk, that could
damage flavor and texture are destroyed by pasteurization.
Rapidly cooled to a temperature below 5°C using a plate heat exchanger.Rapidly cooled to a temperature below 5°C using a plate heat exchanger.
Time and temperature requirements of pasteurization.
Time –temperature combination for ice-cream-
HTST method - 80°C for not less than 25seconds
Batch method – 68.5°C for not less than 30 min

45. Advantages of pasteurizationAdvantages of pasteurization
It renders the mix completely free of pathogenic bacteria
It dissolves and helps to blend the ingredients of the mix
It improves flavour
It improves keeping quality
It produces a more uniform productIt produces a more uniform product

46. HOMOGENIZING THE MIXHOMOGENIZING THE MIX
Most essential step to make a permanent and uniform
suspension of the fat by reducing the size of the fat droplets
to a very small diameter, preferably not more than 2 µm.
Usually done at temperature ranging from 63 to77°c.
Pressure of 2000 to 2500 psi (135 to 170 kg/cm2) with one
valve or 2500 to 3000 psi (170 to 200 kg/cm2) on the first and
500 psi ( 35 kg/cm2) on the second stage will usually give
good results for an average mix.

47. Advantages of homogenizationAdvantages of homogenization
Never allow the fat to form the cream layer
More uniform ice cream
Smoother texture
Improved whipping ability
Shorter ageing periodShorter ageing period
Less opportunity for churning to occur in freezer
Less stabilizer is required

48. Cooling and ageing the mixCooling and ageing the mix
The mix is aged for between 4 – 24 hours at 2 – 5°C under
continuous agitation. During the aging process, the following
occur:
1. Stabilizer draws water and takes full effect
2. Butter fat solidies and crystallize2. Butter fat solidies and crystallize
3. The proteins also impart stabilization effect by drawing
water and swelling.
4. Very little air in the mix results into a soggy and heavy ice
cream.

49. The changes that occurs during ageing
Hydration of milk proteins and stabilizers
Crystallization of fats
Absorption of water by any added hydrocolloids
Viscosity is increased largely due to the previously mentioned
changes.changes.
Ageing is substantially completed within 24 h and longer
period should be avoided to control spoilage by
psychrotrophs.
Increases melting resistance
Increases maximum overrun

50. FLAVOUR MIXING TANKFLAVOUR MIXING TANK
Done at continuous freezing system
Flavours are added by experience to obtain pleasing flavour and
colours should correspond to the flavour
Fresh or canned fruits should be used as pulp or cut into pieces and
added to partially frozen ice cream or as top dressingadded to partially frozen ice cream or as top dressing
Nuts after cut into pieces, roasted
unroasted, should be added to partially frozen ice cream while it is
in the freezer.

51. FREEZINGFREEZING THETHE MIXMIX
After cooling and ageing is frozen in ice cream freezers
Freezer converts mix into ice cream by simultaneously
aerating, freezing and beating
When the drawing temperature is -5.6ºC
To generate the ice crystals
The air bubbles and the matrixThe air bubbles and the matrix
Air is also incorporated to obtain the required over-run in the
semi frozen mass during freezing process

52. Method of freezingMethod of freezing
Batch freezer- horizontal, direct expansion (freon or
ammonia)
Continuous freezer- horizontal, direct expansion
(freon or ammonia)
Soft serve freezer-batch and automatic continuous
/low temp. continuous freezer

53. Changes during freezing processChanges during freezing process
Lowering the temperature of the mix from ageing
temperature to the freezing point
Freezing a portion of water in the mix
Incorporating air into the mix
Cooling ice cream from the temperature at which it is drawnCooling ice cream from the temperature at which it is drawn
from the freezer to hardening room temperature.

54. Continuous ice cream freezersContinuous ice cream freezers

55. OVER RUN OF ICEOVER RUN OF ICE--CREAMCREAM
Amount of air added to the ice cream is called over run.
Incorporation of air into ice cream
Incorporated into the mix depends on the
composition of the mixcomposition of the mix
Air handling system allows for air filtration (0.65 mm
micro pore filter) prior to admission into the mix
Increased volume is composed mainly of air
incorporated during the freezing process

56. The factors that depress overrunThe factors that depress overrun
Fat content
MSNF content
Amount of mix in batch freezer
Poor homogenization
Insufficient refrigeration
Factor listed as enhancing overrunFactor listed as enhancing overrunFactor listed as enhancing overrunFactor listed as enhancing overrun
Sodium caseinate
Whey solids
Emulsifiers
Pasteurization of mix at higher temperature

57. Overrun calculationsOverrun calculations
It is the % increase in volume of ice cream greater than the
amount of mix used to produce that ice cream
# % Overrun
= (Vol. of ice cream - Vol. of mix used)
x 100
Package overrun by weightPackage overrun by weight
# % Overrun
= (Wt. of mix - Wt. of same vol. of ice cream ) Wt.
Vol. of mix used
x 100
Wt. of same vol. of ice cream
x 100

58. FILLING / PACKAGING
When ice cream is drawn from the freezer, it is put into
containers that give it the desired form and size for convenient
handling during the hardening, shipping and marketing
processes.

59. HARDENING OF ICEHARDENING OF ICE--CREAMCREAM
At -35 °C or below
Is to reduce the temperature of the product to at least 0°C of in the
center of the package as quickly as possible
To prevent ice melting and recristallization
The freezing process is continued without agitationThe freezing process is continued without agitation

60. Factors that affect the rate of hardeningFactors that affect the rate of hardening
The temperature and velocity of the circulating air
Temperature of ice cream when drawn from the freezer
Speed of air circulation
Composition of the mix
Percent overrun taken in ice creamPercent overrun taken in ice cream
Size of the containers

61. DEFECTS IN ICEDEFECTS IN ICE--CREAMCREAM
Due to low quality ingredient
Improper heat treatment
Chemical changes
Improper mixing
By growth of micro-organismBy growth of micro-organism
Temperature changes

62. DEFECTSDEFECTS
 Flavour Defects-
• High, low – due to flavoure addition
• Rancid- fat hydrolysis due to lipase action
• Flat - enadequate amount of sugar
• Cooked- overheating during pasteurization
• Oxidized- fat oxidation
 Body and Texture Defects- Body and Texture Defects-
• Crumbly body, Weak Body and Fluffy Texture - low solids and stabilizer
contains, improper homogenization, excessive overrun
• Gummy Body- Too low overrun,Too much stabilizer
 Melting Quality Characteristics-
• Curdy Melt-Down- caused by fat or protein destabilization
 Sandyness (texture defect )
 Colour Defects
 Shrinkage- the loss of moisture- tempreture flucations during storage .

63. References
 Outlines of Dairy Technology – Sukumar De
 Fat-Rich-Dairy-Products-Technology : http:// www.AgriMoon.Com
 Ice-cream-Frozen-Dessrt By- A. Jana , Suneeta Pinto , P.R.S. Moorthy
 Dairy-products-Technology- practical manual & Txt book XII - CBSE Delhi
 Ice Cream (Seventh Edition) - H. Douglas Goff , Richard W. Hartel
 Ice-cream-Frozen-Dessrt By- A. Jana , Suneeta Pinto , P.R.S. Moorthy
 The Chemistry Behind Ice Cream.
Chicago Tribune, June 30, 2004: http://articles.chicagotribune.com/2004-06-
30/entertainment/0406300068_1_ice-cream-homemadeice-ice-crystals-form
[accessed Dec 2013].