EDIBLE FOOD COLORS
By
SAGARIKA DAS
M.Tech
Food Engineering & Technology
CIT KOKRAJHAR
sagarikadas231096@gmail.com
www.linkedin.com/in/sagarika-das
CONTENTS
 INTRODUCTION 3
 HISTORY OF FOOD COLOURS 6
 PURPOSE OF FOOD COLOURING 7
 FORMS OF FOOD COLOUR 10
 TYPES OF FOOD COLOURING 13
 PERMITTED FOR LIMITED USE IN FOODS 20
 APPROVED IN EU 23
 LIMITATION OF USING NATURAL FOOD COLOUR 31
 DYES AND LAKES 33
 POSSIBLE HEALTH BENEFITS 37
2Prepared by : SAGARIKA DAS
INTRODUCTION
 Food colouring, or colour additive, is any dye,
pigment or substance that imparts colour when it is
added to food or drink. They come in many forms
consisting of liquids, powders, gels and pastes. Food
colouring is used for both in commercial food
production and in domestic cooking. (Wikipedia)
 Is any dye, pigment or substance that imparts
colour when it is added or applied to a food, drug,
cosmetics or to the human body .
 It will give manufacturers a complete guide to the
wide range of food colours available, and which
colours will best suit their product, process and
shelf life conditions. It remains the ideal practical
tool for the food industry, and those interested in
the ingredients used to colour food .
3Prepared by : SAGARIKA DAS
4Prepared by : SAGARIKA DAS
WHERE IT IS USED
 Both in commercial food production and in domestic
cooking
- safety and general availability .
 Non-food applications
- cosmetics, pharmaceuticals, home craft projects
and medical devices .
5Prepared by : SAGARIKA DAS
•
• Around 1200 BC (Brown age), Cleopatra and others added saffron in
butter as first colourant to put a rich yellow colour.
• Around 1500 BC, candy makers in Egyptian cities added natural
extracts and wine to improve the products appearance.
• In 1856, William Henry Perkin discovered the first artificial organic
dye, called “mauve” by oxidizing aniline while trying to form an anti-
malaria drug (quinine).
• By 1900, many foods & drugs in U.S. Were artificially coloured with
many blatantly poisonous materials such as lead, arsenic, and mercury
to hide inferior or defective foods.
• In 1906, Congress passed the Food & Drugs Act, which prohibited
the use of poisonous or deleterious colours in food industries.
• In 1962, the first EU directive, focussing on the use of colorants in
foods was published, 36 colours (20natural & 16 artificial ) were
considered safe for human consumption.
• In 2009, Barry Callebaut’s alized IBC brand specialized in colour &
printing technology in food applications has lauched Power Flowers by
tempering cocoa butter and 40% coloring age.
HISTORY OF FOOD COLOURS
6Prepared by : SAGARIKA DAS
PURPOSE OF FOOD COLOURING
• People associate certain colours with certain flavours, and the colour of
food can influence the perceived flavour in anything from candy to wine.
• Colour additives are used in foods for many reasons anything :
 Offset colour loss due to exposure to light, air, temperature
extremes, moisture and storage conditions.
 Correct natural variations in colour.
 Enhance colours that occur naturally.
 Provide colour to colourless and “fun” foods.
 Make food more attractive and appetizing, and informative.
 Allow consumers to identify products on sight, like candy flavours or
medicine dosages
 Food colorants, synthetic.
7Prepared by : SAGARIKA DAS
Indigo Carmine, which is Blue Quinoline Yellow WS,
Which is yellow
 Food colorants, natural
 Food colorants, natural
Anthocyanin, a red to blue dye
Depending on functional groups
and pH
Betanin, a magenta dye,
mainly
Produced from beets 8Prepared by : SAGARIKA DAS
9Prepared by : SAGARIKA DAS
FORMS OF FOOD COLOURING
Liquid
Powder
Gel
Paste
10Prepared by : SAGARIKA DAS
twotTwo General Types
 Artificial Colouring
 Natural Colouring
11Prepared by : SAGARIKA DAS
12Prepared by : SAGARIKA DAS
Types of Food Colouring
 Artificial Colouring
 Current Seven Generally Permitted
 Permitted for Limited Use in Foods
 Delisted and Banned in The US
 Approved in EU
 Natural Food Dyes
 Dyes and Lakes
13Prepared by : SAGARIKA DAS
 Many synthesized dyes were easier and less costly to produce and
were superior in colouring properties when compared to naturally
derived alternatives of the time.
 Also known as “azo-dyes”, the first step forms a
diazo compound from the reaction of aromatic
amines generally formed from nitrosamine and
a diazonium compound. The second step couples
these diazo compounds with various reactive
aromatic hydrocarbons.
 The color of the dyes can be controlled selecting
the number of azo-groups and various substituents.
 Yellow shades are achieved by using aceto-
acetanilide and heterocyclic compounds.
 Red colors result from the reaction between an aniline
derivative (diazo) with a naphthol derivate.
 A Blue results from replacing the aniline derivate with a benzidine
derivate .
ARTIFICIAL COLOURING
Food coloring spreading
On a thin water film in
The International Space
Station
14Prepared by : SAGARIKA DAS
Current Seven Generally Permitted
 FD&C Blue No. 1 -Brilliant Blue FCF,E133
(blue shades)
 FD&C Blue No. 2 –Indigotine, E132
(indigo shade)
FD&C Green No. 3 –Fast Green FCF,E143
(turquoise shade)
FD&C Red No. 3 –Erythrosine,E127
(pink shade, commonly used in glace cherries)
FD&C Red No. 40 –Allura Red AC, E129
(red shade)
FD&C Yellow No. 5 –Tartrazine, E102
(yellow shade)
FD&C Yellow No. 6 –Sunset Yellow FCF,E110
(orange shade) 15Prepared by : SAGARIKA DAS
ERYTHROSINE (RED NO. 3)
 Used in cherries in fruit cocktail and in
Canned fruits for salads, Baked foods,
Dairy products, snack foods
 Side effects : cancer
16Prepared by : SAGARIKA DAS
TARTRAZINE (YELLOW NO. 5)
 Used in Ice cream, cake mixes, Carbonated drinks, fish
sticks, Squashes
 Side effects : hyperactivity, asthma, skin rashes and
migraine
17Prepared by : SAGARIKA DAS
ALLURA RED (RED NO. 40)
 Used in carbonated drinks, Soups, bubble gum, Sauces, Wine
 Side effects : may worsen or induce asthma, rhinitis, utricaris
(hives)
18Prepared by : SAGARIKA DAS
BRILLIANT BLUE (BLUE NO. 1)
 Used in Dairy products, Sweets
 Side effects : hyperactivity and skin rashes, listed as
human carcinogen, causes DNA damage and tumours in
animals .
19Prepared by : SAGARIKA DAS
PERMITTED FOR LIMITED USE IN FOODS
Two days are allowed by the FDA
for limited applications :
 Citrus Red 2 (orange shade)
- allowed only to colour orange
peels .
 Orange B (red shade)
- allowed only for use in hot dog
and sausage casings (not
produced
after 1978, but never delisted )
20Prepared by : SAGARIKA DAS
DELISTED AND BANNED IN THE U.S
 FD&C Red No. 2 –Amaranth, E123
 FD&C Red No. 4
 FD&C Red No.32 was used to colour Florida oranges.
 FD&C Orange No.1 was one of the first water- soluble dyes to be
commercialized, and one of 7 original food dyes allowed under the Pure
Food & Drug Act of June 30,1906
 FD&C Orange No.2 was used to colour Florida oranges.
 FD&C Yellow No. 1,2,3 & 4
 FD&C Violet No. 1.
21Prepared by : SAGARIKA DAS
22Prepared by : SAGARIKA DAS
APPROVED IN EU
E numbers 102-143
cover the range of
artificial colours.
Some artificial dyes
approved for food use
in the EU include :
 E104: Quinoline
Yellow
 E122: Carmoisine
 E124: Ponceau 4R
 E131: Patent Blue V
 E142: Green S
23Prepared by : SAGARIKA DAS
24Prepared by : SAGARIKA DAS
25Prepared by : SAGARIKA DAS
26Prepared by : SAGARIKA DAS
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28Prepared by : SAGARIKA DAS
NATURAL FOOD DYES
 Carotenoids
(E160,E161,E164),
 Chlorophyllin
(E140,E141),
 Anthocyanins (E163), and
 Betanin (E162)
Comprise four main
categories of
Plant pigments grown to
colour
Food products.
29Prepared by : SAGARIKA DAS
 These are colourings approved for use in all types of food
 Although there are other natural colourings that are only approved for
certain uses -
a) Synthetic Iron Oxide – only allowed in sausage casings
b) Ferrous Gluconate and Ferrous Lactate – only allowed in ripe olives
 Other colorants or specialized derivatives of these core groups include :
 Annatto (E160b), a reddish- orange dye made from the seed of the
achiote
 Caramel coloring (E150a-d), made from caramelized sugar
 Carmine (E120), a red dye derived from the cochineal insect,
Dactylopius coccus
 Elderberry juice
 Lycopene (E160d)
 Paprika (E160c)
 Turmeric (E100)
30Prepared by : SAGARIKA DAS
LIMITATIONS OF USING NATURAL
FOOD COLOUR
 Some sources of natural colours have their own flavour which
may affects the taste of the finished product. (Turmeric)
 Actual colour may not retain as such when subjected to high
temperatures. (Grape juice extract)
 Can cause allergic reactions. (Cochineal extract, Annatto)
 Natural food colour are costlier than artificial colourings.
(Saffron)
 At times raw ingredients remains scarce. (Marigold extract)
 Require in large quantities when compared to Artificial dyes.
(Cochineal extract)
31Prepared by : SAGARIKA DAS
FUTURE PROSPECTS OF NATURAL
FOOD COLOURS
Microencapsulation:
- increased light stability will be achieved with encapsulation of
some sensitive colours (annatto & paprika)
Addition of antioxidants :
- to increase nutritional value of some food colours, external
antioxidants (like tocophenols, ascorbic acid and rosemary extract) can
be fortified.
Emulsions :
- by formulating an easy to disperse colour emulsion to remain
stable in many different food applications. (gums or modified starches)
Development of new sources :
- extensive research should be done in introducing new colouring
agents in the market.
Moshfeghi et al,. (2013) recently introduced Dragon Fruit Colouring Powder (DFCP)
As a natural food additive in Malaysian market which is rich in vitamin C & minerals
(potassium, sodium, calcium, iron and phosphorus)
32Prepared by : SAGARIKA DAS
DYES AND LAKES
• Dyes –
 dissolved in water, but are not
soluble in oil.
 they are manufactured as
powders, granules, liquids or other
special purpose forms.
 they can be used in beverages,
dry mixes, baked goods,
confections, dairy products, pet
foods, and a variety of other
products.
 also have side effects that lakes
lack.
33Prepared by : SAGARIKA DAS
34Prepared by : SAGARIKA DAS
• Lakes –
 they are made by combining dyes with salts (usually aluminum salts)
to make insoluble compounds.
 they are not oil-soluble, but are oil-dispersible.
 they are more stable than dyes and are ideal for colouring products
containing fats and oils or items lacking sufficient moisture to dissolve
dyes.
 typical uses include coated tablets, cake and doughnut mixes, hard
candies and chewing gums, lipsticks, soaps, shampoos, talc, etc .
35Prepared by : SAGARIKA DAS
CRITICISM AND HEALTH IMPLICATIONS
 Some FDA –approved food colourings pose certain risks to health.
 Research has linked Erythrosine to thyroid cancer in rats.
 The cochineal insect extract rarely causes sever allergic
reactions .
36Prepared by : SAGARIKA DAS
POSSIBLE HEALTH BENEFITS
 Brilliant Blue FCF could help in the healing of spinal injuries.
Researchers have found that injecting the dye into rats who have just
suffered spinal injuries reduces the chances of paralysis.
It prevents the body from sending a chemical to the site of the injury
which is know for causing further damage to nerve tissue.
37Prepared by : SAGARIKA DAS
Prepared by : SAGARIKA DAS 38
REFERENCE
https://www.larsed-keller.com
 J. B. Hutchings, Food colour and Apperance, Blackie Academic
& Professional, Glasgow, Scotland, 1994 .
 R. G. Kuehni, Color: An Introduction to Practice and Principles,
John Wiley & Sons, NewYork, 1997 .
 F. W. Billmeyer, Jr., and M. Saltzman, Principles of Color
Technology, 2nd ed., John Wiley & Sons, Inc., New York, 1981 .
THANK YOU
39Prepared by : SAGARIKA DAS

EDIBLE FOOD COLOURS

  • 1.
    EDIBLE FOOD COLORS By SAGARIKADAS M.Tech Food Engineering & Technology CIT KOKRAJHAR sagarikadas231096@gmail.com www.linkedin.com/in/sagarika-das
  • 2.
    CONTENTS  INTRODUCTION 3 HISTORY OF FOOD COLOURS 6  PURPOSE OF FOOD COLOURING 7  FORMS OF FOOD COLOUR 10  TYPES OF FOOD COLOURING 13  PERMITTED FOR LIMITED USE IN FOODS 20  APPROVED IN EU 23  LIMITATION OF USING NATURAL FOOD COLOUR 31  DYES AND LAKES 33  POSSIBLE HEALTH BENEFITS 37 2Prepared by : SAGARIKA DAS
  • 3.
    INTRODUCTION  Food colouring,or colour additive, is any dye, pigment or substance that imparts colour when it is added to food or drink. They come in many forms consisting of liquids, powders, gels and pastes. Food colouring is used for both in commercial food production and in domestic cooking. (Wikipedia)  Is any dye, pigment or substance that imparts colour when it is added or applied to a food, drug, cosmetics or to the human body .  It will give manufacturers a complete guide to the wide range of food colours available, and which colours will best suit their product, process and shelf life conditions. It remains the ideal practical tool for the food industry, and those interested in the ingredients used to colour food . 3Prepared by : SAGARIKA DAS
  • 4.
    4Prepared by :SAGARIKA DAS
  • 5.
    WHERE IT ISUSED  Both in commercial food production and in domestic cooking - safety and general availability .  Non-food applications - cosmetics, pharmaceuticals, home craft projects and medical devices . 5Prepared by : SAGARIKA DAS
  • 6.
    • • Around 1200BC (Brown age), Cleopatra and others added saffron in butter as first colourant to put a rich yellow colour. • Around 1500 BC, candy makers in Egyptian cities added natural extracts and wine to improve the products appearance. • In 1856, William Henry Perkin discovered the first artificial organic dye, called “mauve” by oxidizing aniline while trying to form an anti- malaria drug (quinine). • By 1900, many foods & drugs in U.S. Were artificially coloured with many blatantly poisonous materials such as lead, arsenic, and mercury to hide inferior or defective foods. • In 1906, Congress passed the Food & Drugs Act, which prohibited the use of poisonous or deleterious colours in food industries. • In 1962, the first EU directive, focussing on the use of colorants in foods was published, 36 colours (20natural & 16 artificial ) were considered safe for human consumption. • In 2009, Barry Callebaut’s alized IBC brand specialized in colour & printing technology in food applications has lauched Power Flowers by tempering cocoa butter and 40% coloring age. HISTORY OF FOOD COLOURS 6Prepared by : SAGARIKA DAS
  • 7.
    PURPOSE OF FOODCOLOURING • People associate certain colours with certain flavours, and the colour of food can influence the perceived flavour in anything from candy to wine. • Colour additives are used in foods for many reasons anything :  Offset colour loss due to exposure to light, air, temperature extremes, moisture and storage conditions.  Correct natural variations in colour.  Enhance colours that occur naturally.  Provide colour to colourless and “fun” foods.  Make food more attractive and appetizing, and informative.  Allow consumers to identify products on sight, like candy flavours or medicine dosages  Food colorants, synthetic. 7Prepared by : SAGARIKA DAS
  • 8.
    Indigo Carmine, whichis Blue Quinoline Yellow WS, Which is yellow  Food colorants, natural  Food colorants, natural Anthocyanin, a red to blue dye Depending on functional groups and pH Betanin, a magenta dye, mainly Produced from beets 8Prepared by : SAGARIKA DAS
  • 9.
    9Prepared by :SAGARIKA DAS
  • 10.
    FORMS OF FOODCOLOURING Liquid Powder Gel Paste 10Prepared by : SAGARIKA DAS
  • 11.
    twotTwo General Types Artificial Colouring  Natural Colouring 11Prepared by : SAGARIKA DAS
  • 12.
    12Prepared by :SAGARIKA DAS
  • 13.
    Types of FoodColouring  Artificial Colouring  Current Seven Generally Permitted  Permitted for Limited Use in Foods  Delisted and Banned in The US  Approved in EU  Natural Food Dyes  Dyes and Lakes 13Prepared by : SAGARIKA DAS
  • 14.
     Many synthesizeddyes were easier and less costly to produce and were superior in colouring properties when compared to naturally derived alternatives of the time.  Also known as “azo-dyes”, the first step forms a diazo compound from the reaction of aromatic amines generally formed from nitrosamine and a diazonium compound. The second step couples these diazo compounds with various reactive aromatic hydrocarbons.  The color of the dyes can be controlled selecting the number of azo-groups and various substituents.  Yellow shades are achieved by using aceto- acetanilide and heterocyclic compounds.  Red colors result from the reaction between an aniline derivative (diazo) with a naphthol derivate.  A Blue results from replacing the aniline derivate with a benzidine derivate . ARTIFICIAL COLOURING Food coloring spreading On a thin water film in The International Space Station 14Prepared by : SAGARIKA DAS
  • 15.
    Current Seven GenerallyPermitted  FD&C Blue No. 1 -Brilliant Blue FCF,E133 (blue shades)  FD&C Blue No. 2 –Indigotine, E132 (indigo shade) FD&C Green No. 3 –Fast Green FCF,E143 (turquoise shade) FD&C Red No. 3 –Erythrosine,E127 (pink shade, commonly used in glace cherries) FD&C Red No. 40 –Allura Red AC, E129 (red shade) FD&C Yellow No. 5 –Tartrazine, E102 (yellow shade) FD&C Yellow No. 6 –Sunset Yellow FCF,E110 (orange shade) 15Prepared by : SAGARIKA DAS
  • 16.
    ERYTHROSINE (RED NO.3)  Used in cherries in fruit cocktail and in Canned fruits for salads, Baked foods, Dairy products, snack foods  Side effects : cancer 16Prepared by : SAGARIKA DAS
  • 17.
    TARTRAZINE (YELLOW NO.5)  Used in Ice cream, cake mixes, Carbonated drinks, fish sticks, Squashes  Side effects : hyperactivity, asthma, skin rashes and migraine 17Prepared by : SAGARIKA DAS
  • 18.
    ALLURA RED (REDNO. 40)  Used in carbonated drinks, Soups, bubble gum, Sauces, Wine  Side effects : may worsen or induce asthma, rhinitis, utricaris (hives) 18Prepared by : SAGARIKA DAS
  • 19.
    BRILLIANT BLUE (BLUENO. 1)  Used in Dairy products, Sweets  Side effects : hyperactivity and skin rashes, listed as human carcinogen, causes DNA damage and tumours in animals . 19Prepared by : SAGARIKA DAS
  • 20.
    PERMITTED FOR LIMITEDUSE IN FOODS Two days are allowed by the FDA for limited applications :  Citrus Red 2 (orange shade) - allowed only to colour orange peels .  Orange B (red shade) - allowed only for use in hot dog and sausage casings (not produced after 1978, but never delisted ) 20Prepared by : SAGARIKA DAS
  • 21.
    DELISTED AND BANNEDIN THE U.S  FD&C Red No. 2 –Amaranth, E123  FD&C Red No. 4  FD&C Red No.32 was used to colour Florida oranges.  FD&C Orange No.1 was one of the first water- soluble dyes to be commercialized, and one of 7 original food dyes allowed under the Pure Food & Drug Act of June 30,1906  FD&C Orange No.2 was used to colour Florida oranges.  FD&C Yellow No. 1,2,3 & 4  FD&C Violet No. 1. 21Prepared by : SAGARIKA DAS
  • 22.
    22Prepared by :SAGARIKA DAS
  • 23.
    APPROVED IN EU Enumbers 102-143 cover the range of artificial colours. Some artificial dyes approved for food use in the EU include :  E104: Quinoline Yellow  E122: Carmoisine  E124: Ponceau 4R  E131: Patent Blue V  E142: Green S 23Prepared by : SAGARIKA DAS
  • 24.
    24Prepared by :SAGARIKA DAS
  • 25.
    25Prepared by :SAGARIKA DAS
  • 26.
    26Prepared by :SAGARIKA DAS
  • 27.
    27Prepared by :SAGARIKA DAS
  • 28.
    28Prepared by :SAGARIKA DAS
  • 29.
    NATURAL FOOD DYES Carotenoids (E160,E161,E164),  Chlorophyllin (E140,E141),  Anthocyanins (E163), and  Betanin (E162) Comprise four main categories of Plant pigments grown to colour Food products. 29Prepared by : SAGARIKA DAS
  • 30.
     These arecolourings approved for use in all types of food  Although there are other natural colourings that are only approved for certain uses - a) Synthetic Iron Oxide – only allowed in sausage casings b) Ferrous Gluconate and Ferrous Lactate – only allowed in ripe olives  Other colorants or specialized derivatives of these core groups include :  Annatto (E160b), a reddish- orange dye made from the seed of the achiote  Caramel coloring (E150a-d), made from caramelized sugar  Carmine (E120), a red dye derived from the cochineal insect, Dactylopius coccus  Elderberry juice  Lycopene (E160d)  Paprika (E160c)  Turmeric (E100) 30Prepared by : SAGARIKA DAS
  • 31.
    LIMITATIONS OF USINGNATURAL FOOD COLOUR  Some sources of natural colours have their own flavour which may affects the taste of the finished product. (Turmeric)  Actual colour may not retain as such when subjected to high temperatures. (Grape juice extract)  Can cause allergic reactions. (Cochineal extract, Annatto)  Natural food colour are costlier than artificial colourings. (Saffron)  At times raw ingredients remains scarce. (Marigold extract)  Require in large quantities when compared to Artificial dyes. (Cochineal extract) 31Prepared by : SAGARIKA DAS
  • 32.
    FUTURE PROSPECTS OFNATURAL FOOD COLOURS Microencapsulation: - increased light stability will be achieved with encapsulation of some sensitive colours (annatto & paprika) Addition of antioxidants : - to increase nutritional value of some food colours, external antioxidants (like tocophenols, ascorbic acid and rosemary extract) can be fortified. Emulsions : - by formulating an easy to disperse colour emulsion to remain stable in many different food applications. (gums or modified starches) Development of new sources : - extensive research should be done in introducing new colouring agents in the market. Moshfeghi et al,. (2013) recently introduced Dragon Fruit Colouring Powder (DFCP) As a natural food additive in Malaysian market which is rich in vitamin C & minerals (potassium, sodium, calcium, iron and phosphorus) 32Prepared by : SAGARIKA DAS
  • 33.
    DYES AND LAKES •Dyes –  dissolved in water, but are not soluble in oil.  they are manufactured as powders, granules, liquids or other special purpose forms.  they can be used in beverages, dry mixes, baked goods, confections, dairy products, pet foods, and a variety of other products.  also have side effects that lakes lack. 33Prepared by : SAGARIKA DAS
  • 34.
    34Prepared by :SAGARIKA DAS
  • 35.
    • Lakes – they are made by combining dyes with salts (usually aluminum salts) to make insoluble compounds.  they are not oil-soluble, but are oil-dispersible.  they are more stable than dyes and are ideal for colouring products containing fats and oils or items lacking sufficient moisture to dissolve dyes.  typical uses include coated tablets, cake and doughnut mixes, hard candies and chewing gums, lipsticks, soaps, shampoos, talc, etc . 35Prepared by : SAGARIKA DAS
  • 36.
    CRITICISM AND HEALTHIMPLICATIONS  Some FDA –approved food colourings pose certain risks to health.  Research has linked Erythrosine to thyroid cancer in rats.  The cochineal insect extract rarely causes sever allergic reactions . 36Prepared by : SAGARIKA DAS
  • 37.
    POSSIBLE HEALTH BENEFITS Brilliant Blue FCF could help in the healing of spinal injuries. Researchers have found that injecting the dye into rats who have just suffered spinal injuries reduces the chances of paralysis. It prevents the body from sending a chemical to the site of the injury which is know for causing further damage to nerve tissue. 37Prepared by : SAGARIKA DAS
  • 38.
    Prepared by :SAGARIKA DAS 38 REFERENCE https://www.larsed-keller.com  J. B. Hutchings, Food colour and Apperance, Blackie Academic & Professional, Glasgow, Scotland, 1994 .  R. G. Kuehni, Color: An Introduction to Practice and Principles, John Wiley & Sons, NewYork, 1997 .  F. W. Billmeyer, Jr., and M. Saltzman, Principles of Color Technology, 2nd ed., John Wiley & Sons, Inc., New York, 1981 .
  • 39.