Food Flavor Chapter 11 in your textbook - Sulfides

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Food Flavor

• Chapter 11 in your textbook

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Intermolecular Copigmentation
Cyanidin-3-ß-D-glucoside
Cyanidin-3-(6-O-p-coumaroyl- ß-D-glucoside
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Copigment Stacking
Co-Factor

Pigment
Co-Factor
Hyperchromic shift Bathochromic shift
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Anthocyanin Color

• The poor stability of anthocyanins creates the
  need to modify stability or find new sources
• Increase color and oxidative stability
• Result
• More red color at higher pH levels
• Greater application range in foods
• Enhanced antioxidant capacity health benefits

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Flavor Chemistry Flavor is a combination of
taste and aroma Taste - sweet, sour, bitter,
salty - only what can be sensed on the tongue -
nerve sensations for metallic and
astringent Aroma - volatiles are released in
mouth and then sensed in the nasal cavity
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Sensory Impressions

• Visual impression
• Color, size, shape, luster
• Odor
• Volatile, odor-active compounds
• Taste
• Sweet, sour, bitter, salty
• Somato-sensory
• Pain, burning, cold, warmth, astringent, fizzy
• Trigeminal nerve response
• Texture, resistance, elasticity
• Sounds

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Modern Flavor Chemistry

• Savory
• Roast, Pan Dripping, Seared , Grilled , Braised,
  Au jus
• Diary
• Milk, cream, dairy, cheese, butter, sweet brown
  flavors, and dairly masking agents
• Fruit
• Natural, synthetic, WONF, enhancers, mimics,
  green, citrus, floral, tropical, exotic,
  complimentary
• Beverages
• Nutritionally enhanced/fortified, soy milks, tea,
  coffee, liqueurs, energy, fortified waters, dry
  drink bases, syrups

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Sweet
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Molecular Basis of Sweetness

• -OH groups
• Acree and Shallenberger AH/B concept

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Acree and Shallenberger

• (Shallenberger Acree) published a paper
  entitled the "Molecular Theory of Sweet Taste" in
  Nature 1969.
• The model developed in that paper for sweetness
  was based on a structure-activity relationship
  between the simplest sweet tasting compounds and
  their structural features of the stimulants and
  has become known as the AH-B theory.
• The theory described with considerable success
  the structural features necessary for sweetness
  but it was not sufficient to predict sweetness.
• That is, not all compounds that satisfied the
  theory tasted sweet nor was the theory able to
  predict potency level especially for the very
  high potency sweetners subsequently synthesized.
• However, all sweet compounds seemed to have an
  identifiable AH-B feature.

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AH/B Model
AH Weak acid, B - electronegative group
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The perception of sweetness is proposed to be due
to a chemical interaction that takes place on
the tongue Between a tastant molecule and tongue
receptor protein
THE AH/B THEORY OF SWEETNESS A sweet tastant
molecule (i.e. glucose) is called the AH/B-
glycophore. It binds to the receptor B-/AH
site through mechanisms that include H-bonding.
Intermolecular, anti-parallel hydrogen-bonding
interaction
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AH / B-
?
B
Glycophore
Hydrophobic interaction
AH
?
AH
B
Tongue receptor protein molecule
For sweetness to be perceived, a molecule needs
to have certain requirements. It must be soluble
in the chemical environment of the receptor site
on the tongue. It must also have a certain
molecular shape that will allow it to bond to
the receptor protein. Lastly, the sugar must
have the proper electronic distribution. This
electronic distribution is often referred to as
the AH, B system. The present theory of
sweetness is AH-B-X (or gamma). There are three
basic components to a sweetener, and the three
sites are often represented as a triangle.
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Identifying the AH and B- regions of two sweet
tastant molecules glucose and saccharin.
Gamma (?) sites are relatively hydrophobic
functional groups such as benzene rings,
multiple CH2 groups, and CH3
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Saccharin

• Sweetn Low, The 1st artificial sweetener
• Accidentally found in 1879 by Remsen and Fahlberg
• Saccharin use increased during wars due to sugar
  rationing
• By 1917, common table-top sweetener in America
• Banned in 1977 due to safety issue
• 1991, withdrew ban, but with warning label
• 2000, removed warning label
• Intensely sweet, but slight bitter aftertaste

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Aspartame

• Nutrasweet, Equal
• Discovered in 1965 by J. Schlatter
• Composed of aspartic acid and phenylalanine
• 4 kcal/g, but 200 times sweeter
• Approved in 1981 for table-top sweetener and
  powdered mixes
• Safety debating
• 1996, approved for use in all foods and beverage
• Short shelf life, not stable at high temperature

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Sucralose

• Splenda
• 1998, approved for table-top sweetener and use in
  various foods
• Approved already in UK, Canada before US
• Only one made from sugar
• There was a law suit last year of this claim
• Splenda lost.not a natural compound.a bit of a
  deceptive marketing.
• Clean, sweet taste and no undesirable off-flavor

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Acesulfame K

• Sunette, Sweet One
• Discovered in 1967 by Hoechst
• 1992, approved for gum and dry foods
• 1998, approved for liquid use
• Blending with Aspartame due to synergistic effect
• Stable at high temperature and long shelf life
  (3-4 years)
• Bitter aftertaste

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Neotame

• Brand new approved sweetener (Jan. 2000)
• 7,000 13,000 times sweeter than sugar
• Dipeptide methyl ester derivative structurally
  similar to Aspartame
• Enhance sweetness and flavor
• Baked goods, non-alcoholic beverages (including
  soft drinks), chewing gum, confections and
  frostings, frozen desserts, processed fruits and
  fruit juices, toppings and syrups.
• Safe for human consumption

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Reb-A (diterpene glucoside)

• http//www.reb-a.com/

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Food flavors Mixtures of natural and/or
artificial aromatic compounds designed to impart
a flavor, modify a flavor, or mask an
undesirable flavor Natural versus
Artificial Natural - concentrated flavoring
constituents derived from plant or animal
sources Artificial - substances used to impart
flavor that are not derived from plant or animal
sources
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• Most natural flavors are concentrated from
  botanicals
• plants, trees, fruits, and vegetables
• Most artificial flavors are synthesized with high
  purity
• - pharmaceutical flavors

Isolation techniques - Steam distillation - mint
and herbal oils - Solvent extraction - vanilla
oleoresins - Expression - citrus oils -
Supercritical fluid extraction targeted
extractions
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Flavor Houses

• Givaudan
• IFF
• Bell Flavors
• Wild
• Sensus Flavors
• Virginia Dare
• Blue Pacific

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Natural flavors can also be enzymatically or
chemically produced - Fermentation reactions -
Microbial enzymes Saccharomyces
Sp. Lactobacillus Sp. Bacillus Sp. Molds
Maillard flavor compounds Glucose
Glutamic acid chicken Glucose
Lysine burnt or fried potato Glucose
Methionine cabbage Glucose
Phenylalanine caramel Fructose
Glutamic acid chicken Fructose
Lysine fried potato Fructose
Methionine bean soup Fructose
Phenylalanine wet dog
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Artificial Flavors Typically are esters Esters
have pleasant fruity aromas, derived from
acids a condensation reaction ACID
ALCOHOL --gt ESTER WATER Most
artificial flavors are simple mixtures of
esters i.e. Isobutyl formate isobutyl
acetate raspberry
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FERMENTATION and FLAVOR O O
Diacetyl (CH3 C - C CH3 ) is a compound
produced by Yeasts via fermentation of
carbohydrates Major compound in the flavor of
cultured dairy products Butter and butter-like
flavor
Compounds potentially used for diacetyl
formation Lactic acid Oxalacetic
acid Pyruvic acid acetyl lactic
acid Acetaldehyde Citric acid
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Flavor stabalization - Need to protect from
light, heat, oxygen, water - Liquid flavors are
typically dissolved in solvents Partially
hydrogenated oil or brominated vegetable
oil Ethanol, propylene glycol, glycerin
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• Dry flavors are typically encapsulated
• - Spray drying
• - Use of excipients
• Plating - coat flavor onto sugar or salt
• Extrusion - glassy sugar film
• Inclusion complex - beta cyclodextrins
• Secondary coatings - high melting temperature fat

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Flavor interactions pH, tartness of acids
dependent on acid Acidulant, the type of acid
used influences intensity of other
flavors Carbohydrates, can bind flavor
compounds, so less flavor may be needed at low
sugar levels Sweeteners, sweetness can impact
flavor intensity Lipids, flavors partition, fat
helps flavor impact Protein, selective binding
of flavor compounds
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• Flavors complex mixtures of many compounds
• -Amyl, butyl, ethyl esters
• - Amyl acetate sweet fruity/ banana/ pear
• - Amyl caproate sharp fruity/ pineapple
• - Amyl formate sweet/ fruity
• Organic acids containing aldehydes , aromatic
  esters,
• alcohols, ketones
• - Acetic acid vinegary
• - Propionic acid sour milk
• - Butyric acid buttery

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- Green flavors - cis 3-hexenol green leafy -
trans 2-hexenal green apple - Citrus flavors
are mixtures of - Aldehydes - Aromatic
esters - Terpenes - Alcohols - Terpenes -
Limonene sweet citrus/ orange peel - Alpha
pinene warm resinous/ pine-like - Dipentene
fresh citrus/ lemon like
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- Floral aldehydes - Citral floral/ sweet/
lemon (Pledge) - Octanol floral/ fatty/
orange-like - Dairy flavors - chemical and
enzymatic -Short chain fatty acids Aliphatic
alcohols - propyl, butyl, octyl -Lactonones -
large chain delta lactones -Aliphatic
aldehydes -acetyldehyde, butyraldehyde
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- Sulfides - dimethyl, butyl, dimethyl
sulfides -Aliphatic esters - butyrates,
laurates, valerates - Di-keytones - diacetyl,
acetylpropionyl - Lactones - undecalactone (C11)
peach/ sweet - octalactone (C8) cooked
coconut/ sweet
Gamma-Octalactone
http//www.iff.com/Ingredients.nsf/FragIngredients
!OpenForm
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• Brown flavors
• - Caramelized, roasted or burnt character
• Bread-yeast, caramel, chocolate, coffee, maple,
  peanut
• - Sweet brown compounds
• Vanillin sweet/ chocolate-like
• Maltol sweet/ malty/ brown (flavor enhancer)
• Di-hydrocoumarin sweet/ caramel/ nutlike
• - Non-sweet brown compounds
• - Dimethyl pyrazine nutty/roasted
• - 2,3,5 trimethyl pyrazine chocolate/ roasted

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Flavor Compounds Formation by Maillard Reaction
Reducing Sugars and ?-amino acids
N-glycosylamine or N-fructosylamine
1-Amino-1-deoxy-2-ketose (Amadori intermediate)
or 2-Amino-2-deoxy-1-aldose (Heynes intermediate)
Reductones and Dehydroreductones
H2S NH3
Strecker degradation
Amino Acids


Retroaldol Reaction
Glyoxal Pyruvaldehyde Glycerolaldehyde
Strecker Aldehydes CO2 ?-aminoketone
(Methional, NH3, H2S)
Furans Thiophenes Pyrroles
Hydroxyacetone Hydroxyacetylaldehyde Acetoin Acet
ylaldehyde
Heterocyclizaion
Pyrazines Pyridines Oxazoles
Thiazoles Pyrroles
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• - Woody compounds
• - Alpha lonone woody/balsamic/violet/red
  raspberry
• Beta lonone woody/balsamic/black raspberry
• - Spicy compounds
• Cinnamic aldehyde cinnamon
• Eugenol cloves
• Thymol thyme
• Zingerone ginger oil
• Capsicum peppers
• - Sulfur compounds
• - Diallyl disulfide garlic onion
• - Methyl mercaptan natural gas
• - Methyl thio butyrate sour milk

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Sour
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SOURNESS and sour taste is often thought of as
acid However there is not a simple
relationship between acid concentration (pH) and
sourness Organic acids differ in
sourness CITRIC ACID (0.05 N solution) fresh
taste sensation LACTIC ACID (0.05 N solution)
sour, tart PROPIONIC ACID (0.05 N solution)
sour, cheesy ACETIC ACID (0.05 N solution)
vinegar PHOSPHORIC ACID (0.05 N solution)
intense MALIC ACID (0.05 N solution)
green TARTARIC ACID (0.05 N solution) hard
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Bitter
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BITTERNESS cqn be attributed to several
inorganics and organics KI CsCl
MgSO4 Certain amino acids and peptides (dipeptide
leucine-leucine) Alkaloids derived from pyridine
(N-containing 6-membered ring) and purines
A caffeine (1, 3, 7 trimethylxanthine) B
theobromine (from cacao)
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GYCOSIDES are sugars that have been added to a
natural compound. Grapefruits generally have a
bitter taste to them. This is due to the
flavonoid compound Naringin. Naringin actually
has 2 sugars (both glucose) as part of its
structure. Compound is still intensely
bitter. Removal of these sugars with
naringinase, will render the compound
tasteless. Naringin is then converted to
Naringinin. The de-bittering of grapefruit
juice can be done, if desired.
Where rutinoside is the sugar
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Salty
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SALTY depends on the nature of the cation and
anion in the ionic salt crystal structure high
molecular weight salts may be bitter some
salts may even exhibit sweetness
Examples NaCl NaBr NaI KCl LiBr
NaNO3 salty KBr salty bitter Lead
acetate (toxic) sweet
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Trigeminal Response
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HOTNESS (pungency) is characteristic of
piperine in black pepper and capsicum in red
pepper and gingerols in ginger
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Cool is a characteristic of menthol Peppermint
or mint oils
Spicy is a characteristic of eugenol Clove,
nutmeg, cinnamon, bay leaf
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Aromas
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Sources of Aromas in Food

• Natural flavors
• Herbs and spices (some enzymatic rxns)
• Fruits (biosynthesis during ripening)
• Process flavors
• Browning and Maillard
• Lipid oxidation
• Fermentation
• Artificial flavors
• Single compounds with character impact
• Isoamyl acetate bananna

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Allium sp.(onions, garlic, shallots, leeks)

• S-(1-propenyl)-L-cysteine sulfoxide
• Allinase
• 1-propenyl sulfenic acid

Chemical Rearrangement w/heat
Chemical rearrangement
Mercaptans (thios) Disulfides
Thiopropanal S-oxide (Tear maker)
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Lipoxygenase Generated Flavors
green
melon, cucumber
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Vanilla- an extracted flavor
Vanillin
Seed pods of Planifolia (a tropical orchid)
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Sunlight Flavor
Sunlight will induce oxidized flavor and sunlight
flavor and hay-like flavor. Oxidized
flavor Sunlight flavor burnt and / or
cabbage
Riboflavin (B2) Effect on Sunlight Flavor

• Riboflavin is a catalyst for production of the
  sunlight flavor.
• Milk protein and riboflavin sunlight
  sunlight flavor
• 2) Riboflavin increase in milk will increase the
  sunlight flavor
• 3) Riboflavin removal prevent the sunlight flavor

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According to the TG Lee Website

• Studies at the Silliker Laboratories in Illinois,
  the University of Michigan, and other leading
  labs and universities concluded that both
  sunlight and the fluorescent lighting in stores
  could decrease the freshness and flavor of milk
  and the potency of vital vitamins in it. But this
  research also showed that the majority of natural
  and artificial light could be blocked by
  containers that were yellow instead of white.

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Riboflavin Effect on Sunlight Flavor

• Riboflavin is a catalyst for production of the
  sunlight flavor.
• Milk protein and riboflavin sunlight
  sunlight flavor
• 2) Riboflavin increase in milk will increase the
  sunlight flavor
• 3) Riboflavin removal prevent the sunlight flavor