Flavoring Beverages: Opportunities and Challenges

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Flavoring BeveragesOpportunities and Challenges
October 2005

• Andrew G. Lynch, Ph.D.
• Quest International
• Global Citrus Applications Manager
• andrew.lynch_at_questintl.com

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What is Food Science ?
Food Science deals with the physical, chemical
and biological properties of food. Food
Scientists are concerned with Nutrition and
Safety Stability Processing and Packaging Cost
and Quality There are very few things as
personal as food!
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flavoring beverages

• background
• opportunities
• challenges
• citrus flavor stability
• orange juice processing
• clouds
• milk coffee drinks

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Quest for creative difference
key facts

• creative leader in the industry
• corporate headquarters in Naarden, the
  Netherlands
• two businesses Flavours and Fragrances
• total sales US 1.1 billion (2003)
• creative and application centres and production
  facilities across Europe, the Americas and Asia
  Pacific
• approx. 3,500 employees

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Quest for creative difference
sales 2003 US 1.1 billion
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flavoring beverages

• background
• opportunities
• challenges
• citrus flavor stability
• orange juice processing
• clouds
• milk coffee drinks

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opportunities - North American beverage market
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opportunities
market trends

• diet (low carbohydrate, low calorie)
• healthy fats (shift from trans and hydrogenated
  fats)
• shift from fanciful to more exotic natural flavor
• e.g. Blood orange instead of orange
• masking, suppressing smoothing
• innovative beverages

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opportunities
non-alcoholic beverage segment new launch top
flavors 2004
citrus flavors top the list, moving strawberry
from 1 2003 to 3 in 2004. cranberry and
chocolate are new to the list.

• lemon
• orange
• strawberry
• chocolate
• apple
• peach
• mango
• raspberry
• vanilla
• cranberry

Source Global New Products Database (Mintel)
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opportunities
obesity
Obesity in the US is truly an epidemic. In the
last 10 years, obesity rates have increased by
more than 60 among adults.
Source World Health Organization 2003
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opportunities
masking and suppressing

• bitterness
• (soy, grapefruit, protein drinks, coffee)
• sourness
• (coffee, fermented and acid products)
• saltiness
• (iso-tonic applications)
• artificial sweetener
• (low cal products, lingering aftertaste, lack of
  body)

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opportunities
enhancement

• sweetness
• sugar flavors
• aromatics beyond drinking
• odor release prior to consumption, instant teas
  coffees
• visual
• taste modification

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opportunities
innovation in beverages

• dairy-based beverages
• soy and juice combination drinks
• meal replacement (juice/cereal/yogurt)

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flavoring beverages

• background
• opportunities
• challenges
• citrus flavor stability
• orange juice processing
• clouds
• milk coffee drinks

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challenges

• packaging
• regulatory
• consistent quality of natural ingredients
• stability
• processing
• flavor stability
• physico-chemical stability

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challenges
regulatory

• GMO
• natural artificial
• kosher
• nature identical
• global customers
• globalization of flavors
• Halal
• TTB (formerly BATF)

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challenges
consistent quality of natural ingredients

• natural products have natural variation
• focused quality assurance program is critical
• catastrophe in one part of the world? Example
  2004 Florida hurricanes significantly damage
  grapefruit crop

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challenges
processing

• consistency in scale-up transfer to other
  regions
• processing impact on flavor/cloud
• hot fill vs. cold fill
• oxygen control

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challenges
flavor degeneration

• fading
• light induced degradation
• acid hydrolysis
• oxidation

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flavoring beverages

• background
• opportunities
• challenges
• citrus flavor stability
• orange juice processing
• clouds
• milk coffee drinks

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challenges
citrus flavor stability

• oxidation of terpenes
• citral in aqueous low pH
• acid catalyzed hydrations

Source Rouseff, R. and Naim, M. 2000. Citrus
Flavor Stability. In Flavor Chemistry, ed. By
Risch, S.J and Ho, C.T. American Chemical
Society. Pages 101-121.
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challenges
citrus stability demonstration

• soda base
• pH 2.7
• Brix 10.6
• Carbonation 7 g/L
• Good oxygen control
• storage conditions
• 2 weeks at 4C and 2 weeks at 45 C

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challenges
typical off flavor formation in acidic aqueous
solution
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challenges
off flavor formation in lemonade stored at high
ambient temperatures
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challenges
sensory analysis of aged lemonades
3.5
3
2.5
2
1.5
1
0.5
0
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challenges
lemon flavors
less off flavors increased shelf life

citrus flavors that deliver traditional citrus
favorites with authentic taste
profiles
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flavoring beverages

• background
• opportunities
• challenges
• citrus flavor stability
• orange juice processing
• clouds
• milk coffee drinks

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Orange Juice Processing

• Oranges are processed to make not from
  concentrate (NFC) or frozen concentrated orange
  juice (FCOJ)
• Quality must be controlled (variety, growing
  conditions, etc)
• Processing must be closely controlled to
• Deactivate enzymes
• Limit oxygen levels
• Destroy pathogenic and spoilage microorganisms
• Minimize chemical and flavor changes
• Correct packaging and storage conditions must be
  used to deliver safe and stable product to
  consumers.

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Cross section of Orange
Juice vesicles
Flavedo
Albedo
Oil glands
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Citrus Materials Basic Processing
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Overview of Production of Orange Juice Concentrate
Main Products
By-Products
Peel Oil
Oil Phase Water-Phase Aroma
Pulp, Limonene, Citrus Pulp Pellets
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Why does juice need to be pasteurized ?

• (1) Enzyme deactivation
• Deactivation of pectin methyl esterase (PME)
• PME cleaves methyl groups from pectin causing
  cloud loss and gelation
• Calcium (from the juice) interacts with the
  demethylated pectin
• Calcium pectate is insoluble and settles at the
  base of the container
• For Florida-grown Valencia oranges, a heat load
  of 2-3 D values is generally sufficient for total
  enzyme destruction.
• Typically pasteurization conditions employed are
  95-98C for 10-30 secs.

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Why does juice need to be pasteurized ?

• (2) Ensure a microbiologically stable product
• Main micro-organisms of interest in OJ are
• Acid-tolerant bacteria, yeasts and moulds
• Acid-tolerant bacteria, e.g., Lactobacillus
  plantarum (grow best at 20-37C)
• Spoilage characterized by diacetyl (buttery)
  off-notes and CO2
• Saccharomyces cerevisiae is the most common
  spoilage microorganism
• Spoilage characterized by alcoholic fermentation,
  off-flavors and CO2
• Spore-forming microorganisms (thermo-resistant
  acidophilic bacteria)
• In 1992, Alicyclobacillus classified as new genus
• Spoilage characterized by an off-flavor like
  disinfectant or guaicol

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Thermal processing of OJ

• Thermal resistance of microorganisms is
  traditionally expressed in terms
• of D values and Z values.
• D value is the time at a specified temperature
  for the microbial population
• to decrease by 90 or one log cycle (also called
  the decimal reduction time)
• Z value is the change in temperature needed to
  alter the D value by
• one log cycle
• For example, if an organism has a z 10C and a
  D80C 1 min,
• then the D90C 0.1 min and the D70C 10 min.

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Thermal processing of OJ

• Pasteurization destroys most vegetative
  microorganisms but has little effect
• on bacterial spores (Most spores do not grow lt
  pH 4.5).
• long term survival of some pathogens in
  unpasteurized refrigerated juice is possible,
  therefore pasteurization is recommended
• For microorganisms usually found in fruit juices,
  z values are typically 5-7.
• Typical pasteurization temperatures are 75-95C
  for 15 to 30 secs
• For a given increase in temperature, the rate of
  destruction of microorganisms and enzymes
  increases faster than the rate of destruction of
  sensory and nutrient components.
• SummaryDeactivate enzymes, Ensure
  microbiological safety and minimize heat damage
  to nutrient and flavor components.

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Theoretical thermal destruction curves of pectin
methyl esterase, ascospores and vegetative cells
of Saccharomyces cerevisae in orange juice (The
Orange Book, Tetra Pak)
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challenges
packaging

• trend towards less glass and increased use of
  polypropylene and PET (polyEthyleneTerephthalate)
• scalping (loss of flavor into the
  packaging material)
• permeation (movement of compounds through
  packaging materials)
• migration (movement of components of the
  packaging material into food product)

Source Risch, S. 2000. Flavor and packaging
interactions. In Flavor Chemistry, ed. By
Risch, S.J and Ho, C.T. American Chemical
Society. Pages 94-100.
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Barrier properties

oxidation
Flavor
Flavor fading (scalping, permeation)
Permeation rate Diffusion x Solubility P D x S
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Vitamin C stability in different package types
(The Orange Book, Tetra Pak)
AA ½ O2 DHA H20 AA ascorbic acid (vitamin
C), DHA dehydroascorbic acid
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Properties of different polymers P D x S

• Polar polymers PET, ethylene vinyl alcohol
  (EVOH) and polyamide (PA) show very slow
  diffusion coefficients with polar and non-polar
  aroma compounds.
• Non-polar polymers low density polyethylene
  (LDPE), high density polyethylene (HDPE) and
  polypropylene (PP)
• Limonene (non-polar aroma compound) has a high
  solubility in all the non-polar polymers and
  diffusion and consequent permeation rates differ
  by orders of magnitude in the different polymers
  in decreasing order
• LDPE gt HDPE gt PP
• Ethyl butyrate (polar aroma compound) has low
  solubility in non-polar polymers. Losses of polar
  molecules are negligible with this type of
  barrier.

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Terpenes the largest single chemical class
within citrus volatiles

• Three month study of orange juice in Tetra-Pak
  laminated containers showed
• Significant loss of limonene due to
  absorption/scalping by polymer barrier
• a-terpineol (formed from degradation of limonene)
  increased more rapidly at higher storage
  temperatures
• Duerr et al., Alimenta 1981, 20, 91-93

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Volatile contribution to orange juice aroma

• Contribution to typical aromas Contribution to
  off-notes
• Important Desirable Precursors Detrimental
• ethyl butyrate linalool linalool a-terpin
  eol
• neral limonene limonene carvone
• geranial a-pinene valencene t-carveol
• valencene 4-vinyl guaiacol
• acetaldehyde 2,5-demethyl-4- hydro
  xy-3-(2H) furanone octanal
• nonanal
• a-sinensal
• b-sinensal

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flavoring beverages

• background
• opportunities
• challenges
• citrus flavor stability
• orange juice processing
• clouds
• milk coffee drinks

44
challenges
clouds

• provides turbidity to a beverage visual
  enhancement that gives finished beverage more
  value
• many different types of cloud systems
• weighting agents in clouds are regulated
• sucrose acetate isobutyrate (SAIB)
• brominated vegetable oil (BVO)
• ester gum
• blended systems

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challenges
clouds

• Neutral cloud
• Goal cloud with minimal taste impact
• Most made from orange terpenes
• Vegetable oil as an alternative
• typically less stability
• cleaner taste

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challenges
cloud ringing

• emulsion in beverage product breaks down giving
  rise to creaming
• perform tests to predict stability
• make assumptions for predictions
• microscope, particle size analyzer, shelf-life
  studies etc.

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challenges
cloud ringing

• Stokes Law
• V 2gr2 (po-p)
• 9no
• v velocity
• r droplet radius
• g gravity
• po - p difference in density
• no viscosity

v negative creaming v 0 stable cloud v
positive sedimentation
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challenges
cloud ringing
ringing
stable
phase separation, shrinkage of cloud layer
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flavoring beverages

• background
• opportunities
• challenges
• citrus flavor stability
• orange juice processing
• clouds
• milk coffee drinks

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milk-coffee RTD challenges
matrix complexity

• milk-coffee drinks contain coffee, milk,
  sweeteners, flavors, salts, hydrocolloids,
  proteins, emulsifiers amongst other components
• complex mixture of ingredients
• physico-chemical and flavor stability issues
  (processing and storage)

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Milk coffee RTD matrix
Milk coffee RTD matrix
Coffee
Specialty proteins
Alternative systems
Black Coffee
Fresh whole milk Fresh skimmed milk Skim/whole
milk powders
Caseinate
Clouds
Whey proteins
Others
Others
Dairy/non-dairy fat with milk flavour
Effect of heating, antioxidants, pH, O2 content,
stabilizing salts, homogenization etc.
Processing
Emulsifiers, Proteins Hydrocolloids
RD
Application, Sensory Flavour expertise
Beverages with improved stability fresher
coffee flavour
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milk-coffee RTD opportunities
consumption

• coffee consumption is growing
• 2.5 billion liters of canned coffee are consumed
  annually in Japan alone!
• served hot during winter cold in summer
• beverage manufacturers are adopting coffee house
  trends into RTDs

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milk-coffee RTD challenges
flavor complexity

• coffee contains over 830 volatile components!
• some of the key flavor components responsible for
  freshroast coffee character are
• 2-furfurylthiol
• coffee aroma and taste is dependent on the type
  of coffee used
• species Arabica or Robusta
• origin
• degree of roasting

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milk-coffee RTD challenges
flavor complexity

• at temperatures gt 60C, acidity increases,
  sourness increases and volatiles are lost
  resulting in an unpleasant drinking experience
• milk is added to coffee for
• appearance
• taste
• mouthfeel

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LC Fractionation of Arabica Coffee (filtered brew)
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milk-coffee RTD challenges
flavor complexity

• coffee flavors are needed to compensate for the
  damage to the coffee volatiles during the
  extraction and beverage processing stages
• fruity (eg. acetaldehyde)
• phenolic (eg. guaiacol)
• earthy (eg. 2-ethyl-3,5-dimethylpyrazine)
• roast (eg. 2-furfurylthiol)
• sweet (eg. methylpropanal)
• opportunities for flavored coffees include
• vanilla
• Irish Cream
• chocolate and caramel
• macadamia Nut and Hazelnut

• amaretto and almond
• coconut
• fruit flavors eg.
  orange raspberry

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The composition of milk
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Main fatty acids of milk fat
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Distribution of the major constituents of the
casein micellebetween the serum and micellar
phases of bovine milk at pH 6.7 at 20C
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Some physico-chemical characteristics of casein
micelles
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Schematic representation of a sub-micelle (A) and
a casein micelle (B) composed of sub-micelles
(from Schmidt, 1982)
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Possible reactions of side-chain residuesof
proteins at high temperatures 1
1.
-CH2-CONH2 H2O Asparagine
-(CH2)2-CONH2 H2O Glutamine
2.
3.
-CH2-O-PO32- H2O Phosphoserine
4.
-CH2-O-PO32- Phosphoserine
-CH2-SH OH- Cysteine
5.
R1-CH2-S-S-CH2-R2 R3-CH2-S-
6.
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Possible reactions of side-chain residuesof
proteins at high temperatures 2
7.
-CH-S- -S-CH2- Cysteine
-CH2-S- Cysteine
8.
9.
CH2 HS-CH2-
10.
-(CH2)4-NH3 H2C OH- Lysine
-(CH2)4-NH3 -O2C-CH2 Lysine Aspartic acid
11.
-(CH2)4-NH3 -O2C-(CH2)2- Lysine Glutamic acid
12.
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Browning (Maillard) reactions in milk

• in milk the main Maillard reactants are lactose
  and lysine
• the rate of Maillard reaction in milk is
  dependent on pH, time, temperature and water
  activity
• some of the compounds identified from dry
  extracts of milk systsems incubated at pH 6 or 7
  and water activity 0.75 to 0.80 included
  5-hydroxymethyl-furfural, furfuryl alcohol,
  furfural, maltol, acetol, 2-oxo-proponal,
  acetaldehyde, and formic, acetic, propionic,
  butyric and lactic acids

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Heat stability versus pH curvesfor normal skim
milk heated at 140C
HEAT COAGULATION TIME (HCT) (min.)
50
40
maximum
30
milk B
milk A
20
minimum
10
0
6.2
6.4
6.6
6.8
7
7.2
pH
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Changes which can occur to milk constituents on
heating 1

• calcium and phosphate are converted from soluble
  to colloidal state
• formic acid and lactulose are formed from lactose
  at temperatures gt 100C
• hydrolysis of the phosphoserine residues at high
  temperatures
• the titratable acidity of the milk increases and
  pH decreases
• solubility of the whey proteins decreases
  significantly at temperatures gt 75C

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Changes which can occur to milk constituents on
heating 2

• enzymes are inactivated by heating at gt 50C, but
  varies with enzyme
• there is a decrease in redox potential probably
  due to the formation of free sulphydryl groups
  and hydrogen sulphide formation at temperatures gt
  60C
• Maillard reactions increase as temperature of
  heating increases
• casein micelles may start to aggregate above
  110C
• lactones and methyl ketones are formed from the
  fat

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Alkaline urea-PAGE of solutions of sodium
caseinate heated at different pH values and
temperatures.
as1-casein
as2-caseins
Alkaline urea-PAGE of unheated sodium caseinate
(1) sodium caseinate, pH 7, heated at 110C (2),
120C (4), of 130C (6) for 5 min. and sodium
caseinate, pH 10.0, heated at 110C (3), 120C
(5) or 130C (7) for 5 min. Lynch, Andrew, Ph.D
thesis, NUI, Cork, Ireland, 1995.
b-casein
k-casein
g-casein
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milk-coffee RTD challenges
preparation of milk-coffee beverages

• Coffee-milk mixtures usually have near neutral pH
  values and careful processing is required to
  ensure a stable product with good organoleptic
  properties
• controlled temperature duration of heating
  during coffee extraction
• homogenization is required if milk fat or other
  fat is used
• sufficient amount of surface active material
  must be present
• check coffee-milk/ingredient and flavor
  compatibility
• pH of the mixture needs careful control
• sterilization/UHT processing is required for
  long shelf-life products

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milk-coffee RTD challenges
why homogenize?
under homogenization
optimum homogenization
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milk-coffee RTD challenges
emulsion stability
OIL
Creaming
Coalescence separation
Aggregation creaming
Reversible
Irreversible
STABLE
UNSTABLE
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milk-coffee RTD challenges
droplet stabilitly
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Emulsifiers

• Surface active molecules
• Contain water-loving hydrophilic part and
  oil-loving lipophilic part
• Reduce surface tension
• Orientate at oil / water or air / water interface
• Interact with other ingredients (e.g. protein,
  starch)

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Emulsifiers Chemical Characteristics

• Iodine value unsaturated fatty acids
• gram iodine absorbed per 100 g emulsifier
• Peroxidase value oxidation level
• meq. oxygen bound as peroxide per kg emulsifier
• Acid value free fatty acids
• mg KOH needed to neutralise 1 g emulsifier
• Saponification value free bound fatty acids
• mg KOH needed to saponify 1 g emulsifier

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Composition of emulsifiers
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Hydrophilic / Lipophilic Balance of Emulsifiers
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• Monoglyceride Saturated

E
-o-
-OH
-OH
GMP (glyceromonopalmitate)
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• Sodium stearoyl-2-Lactylate

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milk-coffee RTD challenges
effect of homogenization pressure on particle
size distribution

volume
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flavoring beverages

• background
• opportunities
• challenges
• citrus flavor stability
• orange juice processing
• clouds
• milk coffee drinks

81
Flavoring BeveragesOpportunities and Challenges

• A.G. Lynch