Description
Transition metals Reactions driven by transition metals (Fe, Cu) and compare 2 foods affected by the reactions.：Beef and Oyster Profile the composition of two specific foods or ingredients differ in terms of their iron (Fe) and copper (Cu) contents and proximate profiles, and describe the similarities and differences? What are the chemical speciation (ie, oxidation state) of metals present? Is oxygen present in these foods? At what level? How is the oxygen and light exposure managed for these foods?
Unformatted Attachment Preview
FSC5010 Food Chemistry
Assignment 1A: Exploring the chemistry of a food
Assessment Rubric
Ratings
Criteria
1. Layout and clarity
20%
Contains abstract,
conclusion, references,
appropriate use of
subheadings, flow of
review, adherence to
word limit. Language,
spelling and grammar.
2. Abstract 10%
Not demonstrated
Developing
Achieved
Exemplary
0
There is a basic flow from
one section to the next,
but not all sections follow
in a logical order. There is
no indication of an
attempt to use of suitable
subheadings and/or
adhere to formatting
requirements. Language is
too complex or simplistic
and impacts the research /
message and accuracy of
information. Numerous
spelling and/or
grammatical errors
throughout. Many
sections of content have
been taken directly from
original research paper
without individual
synthesis and expression.
1 to 4
There is a basic flow from
one section to the next,
but not all sections
follow in a logical order.
Lacking use of suitable
subheadings. Formatting
somewhat adhered to.
Language is too complex
or simplistic in parts and
impacts part of the
message and accuracy of
information, and/or
some sections of content
have been taken directly
from original research
paper without individual
synthesis and expression.
Some spelling and/or
grammatical errors
throughout that impact
presentation and
understanding. Needs
significant changes to
language and grammar.
1 to 2
5 to 6
You have clearly set out the
literature review in a logical
and scientific manner,
including suitable
subheadings and adhering
to all formatting
requirements. Language is
mostly suitable and
provides a clear idea of the
message. Minor/minimal
spelling and grammatical
errors that have some
impact on presentation and
understanding.
7 to 8
You have clearly set out the
literature review in a logical
and scientific manner,
including suitable
subheadings and adhering
to all formatting
requirements. Current
format suitable for use in
the professional context.
Language is of a high
standard, clearly and
accurately articulating the
message; No spelling or
grammatical errors
throughout; No changes
required to language and
grammar.
3
4
0
Max
40 Pts
8
4
A brief overview
The abstract is either
missing or incomplete
Your abstract partially
covers the key content.
Significant gaps in
content and clarity.
Major inaccuracies in
alignment with the
purpose and findings of
your assignment
1 to 2
You may/may not be
aware of the overall
topic. Some sections of
the pertinent content are
included, but not
covered in as much
depth, or as explicit, as
expected.
Your abstract is mostly
concise, covering most key
content. Some areas could
be more succinct. Minor
inaccuracies in alignment
with the purpose and
findings of your assignment
You have succinctly
summarised the key
content. Your abstract is
clear and accurately reflects
the purpose and findings of
your assignment
3. Introduction 10%
Setting the context and
describing the content
0
Neither implicit nor
explicit reference is made
to the topic or purpose of
your literature review
3
You are aware of the overall
topic. Most major sections
of the pertinent content are
included, but not covered in
as much depth, or as
explicit, as expected.
0
Very basic detail with
significant omissions,
irrelevant and/or incorrect
information. There is no
indication of an attempt to
synthesise the information
1 to 8
Your exploration of
relevant topics related to
the target food is
somewhat incomplete.
There is an effort to
explain the relationships
to the target food but
they are not well
supported
9 to 12
You have thoroughly
explored relevant topics
related to the target food,
demonstrating a clear
understanding of their
significance. Your
reflections on the
relationships to the target
food are somewhat
insightful and supported
0
There is no indication of
an attempt to make a
conclusion based on the
1 to 2
You provide some
concluding remarks,
however these are of
3
You provide concluding
remarks that show an
analysis and synthesis of
4
You have clearly introduced
the topic, and groundwork
is laid as to the need and
direction of your literature
review. The appropriate
content under
consideration is covered in
depth without being
redundant
13 to 16
You have thoroughly
explored relevant topics
related to the target food,
demonstrating a clear
understanding of their
significance. Your
reflections on the
relationships to the target
food are insightful and
well-supported, showcasing
exceptional critical thinking
and depth of analysis
4
You were able to make
succinct and precise
conclusions based on the
4. Body of review – the
details 40%
Relevance of topics and
reflection of
relationships to the
target food explained
5. Conclusion 10%
Summary and
implications
4
16
4
aim and literature under
review
6. References 10%
Quality, appropriateness,
and correct formatting
0
Limited or no attempt to
source and/or cite (either
in-text citations, and/or
reference list) scientific
sources
poor quality and are not
supported in the body of
the review, and/or taken
directly from the
research without
showing analysis or
synthesis of ideas
occurring. Needs
significant changes to be
used in a professional
context
1 to 2
Some attempt to
reference but done
improperly or not
sufficiently; did not use
correct referencing
format and/or
inappropriate type
and/or number of
references used.
ideas has occurred. Some of
the conclusion, however,
are not supported in the
research, and/or are not
covered in as much depth,
or as explicit as expected.
Minor adjustments required
for use in the professional
context
aim and body of the
research topic. Current
format suitable for use in
the professional context
3
Scientific references from
reputable academic sources
(e.g., Peer-reviewed journal
articles, Government
publications etc.) and
appropriate number used.
Some errors in formatting
of in-text citations and/or
reference list.
4
Quality scientific references
from reputable academic
sources (e.g., peer-reviewed
journal articles, government
publications etc.) and
appropriate number used.
Correct formatting of in-text
citations and end-of-text
reference list
4
FSC5010 Food Chemistry
Assignment 1A: Exploring the chemistry of a food
Assessment Rubric
Ratings
Criteria
1. Layout and clarity
20%
Contains abstract,
conclusion, references,
appropriate use of
subheadings, flow of
review, adherence to
word limit. Language,
spelling and grammar.
2. Abstract 10%
Not demonstrated
Developing
Achieved
Exemplary
0
There is a basic flow from
one section to the next,
but not all sections follow
in a logical order. There is
no indication of an
attempt to use of suitable
subheadings and/or
adhere to formatting
requirements. Language is
too complex or simplistic
and impacts the research /
message and accuracy of
information. Numerous
spelling and/or
grammatical errors
throughout. Many
sections of content have
been taken directly from
original research paper
without individual
synthesis and expression.
1 to 4
There is a basic flow from
one section to the next,
but not all sections
follow in a logical order.
Lacking use of suitable
subheadings. Formatting
somewhat adhered to.
Language is too complex
or simplistic in parts and
impacts part of the
message and accuracy of
information, and/or
some sections of content
have been taken directly
from original research
paper without individual
synthesis and expression.
Some spelling and/or
grammatical errors
throughout that impact
presentation and
understanding. Needs
significant changes to
language and grammar.
1 to 2
5 to 6
You have clearly set out the
literature review in a logical
and scientific manner,
including suitable
subheadings and adhering
to all formatting
requirements. Language is
mostly suitable and
provides a clear idea of the
message. Minor/minimal
spelling and grammatical
errors that have some
impact on presentation and
understanding.
7 to 8
You have clearly set out the
literature review in a logical
and scientific manner,
including suitable
subheadings and adhering
to all formatting
requirements. Current
format suitable for use in
the professional context.
Language is of a high
standard, clearly and
accurately articulating the
message; No spelling or
grammatical errors
throughout; No changes
required to language and
grammar.
3
4
0
Max
40 Pts
8
4
A brief overview
The abstract is either
missing or incomplete
Your abstract partially
covers the key content.
Significant gaps in
content and clarity.
Major inaccuracies in
alignment with the
purpose and findings of
your assignment
1 to 2
You may/may not be
aware of the overall
topic. Some sections of
the pertinent content are
included, but not
covered in as much
depth, or as explicit, as
expected.
Your abstract is mostly
concise, covering most key
content. Some areas could
be more succinct. Minor
inaccuracies in alignment
with the purpose and
findings of your assignment
You have succinctly
summarised the key
content. Your abstract is
clear and accurately reflects
the purpose and findings of
your assignment
3. Introduction 10%
Setting the context and
describing the content
0
Neither implicit nor
explicit reference is made
to the topic or purpose of
your literature review
3
You are aware of the overall
topic. Most major sections
of the pertinent content are
included, but not covered in
as much depth, or as
explicit, as expected.
0
Very basic detail with
significant omissions,
irrelevant and/or incorrect
information. There is no
indication of an attempt to
synthesise the information
1 to 8
Your exploration of
relevant topics related to
the target food is
somewhat incomplete.
There is an effort to
explain the relationships
to the target food but
they are not well
supported
9 to 12
You have thoroughly
explored relevant topics
related to the target food,
demonstrating a clear
understanding of their
significance. Your
reflections on the
relationships to the target
food are somewhat
insightful and supported
0
There is no indication of
an attempt to make a
conclusion based on the
1 to 2
You provide some
concluding remarks,
however these are of
3
You provide concluding
remarks that show an
analysis and synthesis of
4
You have clearly introduced
the topic, and groundwork
is laid as to the need and
direction of your literature
review. The appropriate
content under
consideration is covered in
depth without being
redundant
13 to 16
You have thoroughly
explored relevant topics
related to the target food,
demonstrating a clear
understanding of their
significance. Your
reflections on the
relationships to the target
food are insightful and
well-supported, showcasing
exceptional critical thinking
and depth of analysis
4
You were able to make
succinct and precise
conclusions based on the
4. Body of review – the
details 40%
Relevance of topics and
reflection of
relationships to the
target food explained
5. Conclusion 10%
Summary and
implications
4
16
4
aim and literature under
review
6. References 10%
Quality, appropriateness,
and correct formatting
0
Limited or no attempt to
source and/or cite (either
in-text citations, and/or
reference list) scientific
sources
poor quality and are not
supported in the body of
the review, and/or taken
directly from the
research without
showing analysis or
synthesis of ideas
occurring. Needs
significant changes to be
used in a professional
context
1 to 2
Some attempt to
reference but done
improperly or not
sufficiently; did not use
correct referencing
format and/or
inappropriate type
and/or number of
references used.
ideas has occurred. Some of
the conclusion, however,
are not supported in the
research, and/or are not
covered in as much depth,
or as explicit as expected.
Minor adjustments required
for use in the professional
context
aim and body of the
research topic. Current
format suitable for use in
the professional context
3
Scientific references from
reputable academic sources
(e.g., Peer-reviewed journal
articles, Government
publications etc.) and
appropriate number used.
Some errors in formatting
of in-text citations and/or
reference list.
4
Quality scientific references
from reputable academic
sources (e.g., peer-reviewed
journal articles, government
publications etc.) and
appropriate number used.
Correct formatting of in-text
citations and end-of-text
reference list
4
FSC5010 Food Chemistry
Assignment 1A
Exploring the chemistry of food
Individual or
Group:
Format:
Length:
Audience:
Topic:
Submission
Date:
Weighting:
Individual report within a team topic (N=3)
The main topic will be divided into three sub-topics, with each group member responsible
for addressing one sub-topic. Each group member is required to individually conduct a
literature review, focusing on a specific sub-section assigned within their main topic. The
review should involve a critical analysis of the chosen sub-topic, utilizing credible
reference sources. A concise abstract summarizing the key content (100 words) and a
conclusion are expected.
1000 words, excluding the Abstract (100 words), references and graphics. You are
permitted and encouraged to include no more than 1 Table and/or 1 Figure.
Language style suitable for the technical manager of a food company.
Each group will choose ONE main topic to study. This topic may be beyond the content of
the course so far, and you are expected to search and review literature using library
resources. You will be able to assign yourself in a group on Moodle.
End of Week 4. The assignment must be uploaded to Moodle by 9:00 AM on the Monday
of University Week 5. You must submit a single document saved as a Word file to the
Moodle drop box. Moodle will not accept any other format.
10%
Context:
The chemistry of food has many facets that include: chemical composition, analysis and chemical reactivity of
components that occur in-food and in-process. If you think about the large number of chemical classes and
then the enormous number of individual compounds, there is extensive potential for multiple interactions
with possible effects on properties. Some of these effects have minor impacts whereas some have major
consequences for food properties, quality, and consumer acceptance. A technologist of food therefore
requires familiarity with the broad scope of food composition and the relationships with properties that
produce either desirable or undesirable outcomes or other criteria of interest to a stakeholder. Occasionally,
the relationships among specific internal components of food can pose challenges in terms of quality,
regulation, and management, especially when there are potential risks to food safety or consumer health.
The topics for this assignment are built upon the FSC5010 weekly topics and will explore some of these
interesting relationships.
Guidelines:
The following guidelines should help you to write your Literature Review, and you should also consult the
marking rubric available on Moodle.
● You may use any suitable headings for the topic but must include an Abstract (100 words) and a
Conclusion.
● Each team member will be addressing a sub-topic and writing their own individual reports. You
should consult with your team members and agree on which subtopic you will work on. Define all the
food components and terms in the subtopic you are working on and develop a series of headings
that reflect the approach you are taking to explore the subtopic and guide the reader through the
subtopic. There is no correct way to write about the subtopic, but your approach and conclusion
should be supported by the literature and resources cited.
● The literature review developed in Assignment 1A will help you to prepare your final report for
Assignment 1B (group assignment) which will include an Industrial challenge linked to the
Assignment 1A main topic.
●
●
●
Use appropriate scientific and academic literature to explore the analysis of your assigned topic.
You may include no more than 1 Table and/or 1 Figure but this is not compulsory.
You should use and cite credible references and sources of information, such as government bodies,
and peer-reviewed journal articles (at least 10 but less than 30 sources). The required citation style is
in the APA style: https://guides.lib.monash.edu/citing-referencing/apa7th. If required, Monash
Library can assist: https://www.monash.edu/library/help/citing-and-referencing.
5/03/2024
Week 1: Food Composition and
Consumer Benefit
1
Think about the foods you have eaten in the last 24 hours
⮚ What are the dominant macronutrients?
⮚ Were they rich in: Carbohydrates/Lipids/Proteins/coloured
by natural components?
⮚ Do you know what are the typical ratios of macro-nutrients
in the foods you like to eat?
2
5/03/2024
Food Carbohydrates
• Carbohydrates contain C, H, O
• Functional groups
• Aldoses and Ketoses
• Main categories
Cm(H2O)n (usually, m=n)
Hydroxyl (C-OH) and carbonyl (C=O)
Based on C=O position; Different reactivity
Monosaccharides, disaccharides and
polysaccharides
3
Monosaccharides
• Common monosaccharides are
hexoses
Common hexose is glucose (Aldose)
C6H12O6
Straight chain to 6-membered ring
(pyranose)
• Isomerism create different hexoses with
the same molecular formulae
i.e., Fructose (Ketose): C6H12O6
Straight chain to 5-membered ring
(furanose)
4
5/03/2024
Further details on glucose..
• Glucose has optical isomers
Not superimposable
• Identical but differ in the ability to rotate the
plane of polarized light (i.e., to right or left)
D-glucose is predominant in nature (Dextrose)
• Two isomers: α-D-glucopyranose and β-D-glucopyranose
• Direction of the –OH group on the anomeric C
is different (i.e., upwards or downwards the
plane)
5
Disaccharides
• Two monosaccharides joined by an ether
linkage (glycosidic bond)
Dimers
Maltose (barley and malt);
C12H22O11
Ring-to-ring bond: α-glycosidic
Lactose (milk)
Ring-to-ring bond: β-glycosidic
Sucrose (table sugar)
Ring-to-ring bond: α-glycosidic
6
5/03/2024
Oligosaccharides and Polysaccharides
• Monosaccharides have multiple
–OH groups
Possibility for multiple ring-to-ring linkages of
• Polymeric structures
Short chain Oligosaccharides (n=3-10) and
monosaccharides
large chain Polysaccharides (n>40)
a) Starch: α-glycosidic
• Two main glucose-based
polysaccharides:
Digestible carbohydrate (wheat, rice,
potatoes)
b) Cellulose: β-glycosidic
Indigestible carbohydrates (dietary fiber)
7
Food Lipids
• Three main categories
Triglycerides, phospholipids, sterols
• Fatty acids (FAs) are long-chain carboxylic Building blocks of triglycerides &
phospholipids
acids: RCOOH
R: Hydrocarbon chain with 12- 22 C atoms
8
• R with single C-C bonds
Saturated FAs; solids at room
• R with one or more double bonds
Mono- or poly-unsaturated FAs; liquids
temperature; in animal fats,
at room temperature; in vegetable and
fish oils
5/03/2024
Further details on unsaturated FAs..
• Double bonds change the
geometry (i.e., pentanoic acid
from tetrahedral to planar
trigonal)
• Categories of unsaturated FAs
based on the distribution of
double bonds
cis and trans
1st double bond, from the methyl
end, at the 3rd C atom (ω-3), 6th C atom
(ω-6) or 9th C atom (ω-9)
9
Triglycerides (TGs)
• Esterification of the –OH of the glycerol
molecule with a FA
• Free FAs are hydrophilic; TGs are
hydrophobic
10
• Physical and chemical properties:
– Depend on the FA structures
Number of C atoms, degree of
• FA commonly found in food have even
numbers of C atoms, and cis configuration
cis to trans conversions occur during
unsaturation, position(s) of the double
bond(s) and geometric isomerism
food processing, forming trans fats, that
have deleterious health effects
5/03/2024
Phospholipids
• Esterification of the three –OH groups of Hydrophilic polar end and lipophilic
glycerol with two FAs and one polar
non-polar end
phosphate molecule
Amphiphilic (soluble in both polar and
non-polar solvents)
Used as emulsifiers, to combine
immiscible polar and non-polar media
into a single phase
11
Sterols
• Sterols are a class of hydrophobic
ringed lipid molecules
12
Common examples include:
▪ Cholesterol
▪ 7-dehydroxycholesterol (involved in the
photosynthesis of vitamin D)
▪ Plant sterols (phytosterols, phytostanols
and their fatty acid esters)
5/03/2024
Food Proteins
• Proteins are formed by alpha amino
acids (AAs)
• >500 AAs found in nature; but only 21
are utilized by human
AAs have a chiral alpha C bonded to:
-COOH group, -NH2 group, H atom, any
1 of 21 different groups
Leads to two optical isomers (D/L);
predominant isomer is the L- isomer
• Two AAs bond via an amide link also
known as peptide bond for proteins
-COOH of 1 AA with –NH2 of the
other AA form Dipeptides
13
Further details on proteins..
• Continued linkage of AAs form
polypeptides
• Peptide chains with fewer than 50 AA
residues
AA units within a peptide: residues
– Lost a water molecule when the peptide
bond is formed
Peptides
• Polypeptides with 50 or more AA residues Proteins
14
5/03/2024
Further details on proteins..
• Primary structure: Linear AA sequence to form a polypeptide chain
• Secondary structure: Natural folding of the polypeptide chain
Regions are stabilized by H-bonds
1) Alpha-helix: Intramolecular H-bonds
2) Beta-pleated sheets: Intermolecular H-bonds
• Tertiary structure: 3D arrangement of the polypeptide chain
Intra-molecular forces (i.e., H-bonding, dispersion
forces and covalent bonds) between the R-groups
• Quaternary structure: Two or more polypeptide chains bound
intermolecular forces
15
Enzymes
• Proteins with 3D ‘quaternary’ structures
– Bind to a specific substrate
– Drive chemical reactions
• Loss of activity in an enzyme:
– Damage to the active site
16
An active site:
• Controlled by the protein structure
• Can be regenerated
• Repeat same chemical reaction for a
new substrate molecule
Factors that affect enzyme activity:
• Any treatment or condition that can
modify protein structure
(i.e., pH, temperature, concentration of
electrolytes, shear and pressure)
5/03/2024
Minerals, Vitamins and Functional foods
Minerals
• Inorganic substances
• 15 essential minerals
Major minerals
• Constitute roughly 4% of body weight in humans
• Ca2+, K+, Mg2+, Na+ (monoatomic cations)
• Cl-, PO43-, S (non-metals ions)
• Fe, Zn, Cu, Mn, Mo, I, F, Se (Trace minerals)
17
Vitamins
• Fat soluble vitamins (A, D, E,
K)
Long-chain unsaturated hydrocarbon chains and
hydrocarbon rings; Consumed in either oil or fat
matrices
Vitamin A
Vit A: Retinol esters and β-carotene (Carrot, sweet
potato)
Vitamin D3
Vit D: D2, D3 (Flesh of fatty fish and fish liver oils )
Vit E: γ-tocopherol, α-tocopherol (Almond, avocado)
Vitamin E
Vitamin K
18
Vit K: K1, K2, K3 (Broccoli, kale)
K1: monounsaturated 20 C branched
hydrocarbon chain
K2, K3: polyunsaturated 20 and 35 C branched
hydrocarbon chains
5/03/2024
Further details on vitamins..
• Water soluble vitamins (Vit C, 9 B-vitamins)
• Vitamin C
• Vitamin B
B1 (thiamine)
B2 (riboflavin)
B3 (niacin)
B5 (pantothenic acid)
B6 (pyridoxine, pyridoxal, pyridoxamine)
B7 (biotin)
B9 (folate, folic acid )
B12 (cobalamin)
Water-soluble; polar functional
groups
Vit C: Easily oxidize; function as
an antioxidant (Citrus fruits,
papaya)
Vit B: Polar functionalities by
hydroxyl, aldehyde, amino, amide,
phosphate and carboxyl groups
(Fish, beef liver, chicken)
19
Functional foods
• Contain one or more compounds
known to have beneficial
properties beyond simple
nutritional function
• Isoprenoids (terpenoids)
In food prior to processing; Consume as it is;
Externally add to increase concentration
5-C isoprene units
• Fruits and vegetables
• Flavours and odors
• Fortified for antioxidant activity (i.e., carotenoids,
tocopherols, phytosterols)
• Phenolics
Polyaromatic molecular structures with –OH
• Anti-oxidant, anti-bacterial, anti-inflammatory
and anti-cancer activity (i.e., Coumarins, Flavonoids,
Anthocyanidins, Flavonones)
20
5/03/2024
Further details on functional foods..
• Fatty acids
ω-3 fatty acids:
• Reduce risk of cardiovascular disease
• Conjugated Linoleic Acids
In fat and milk of ruminants
• Weight loss, heart disease prevention
21
Food Flavours and Colours
Natural attribute of a food, acquired during cooking, or added during processing and
cooking
Food flavours
Sweetness:
• Compounds with one or
more dipolar bonds
• Opportunities for H-bonding
between the molecules and
the sweetness receptors
Sourness:
• Presence of weak acids
(i.e., low molecular weight
carboxylic acids)
22
Natural sweeteners: monosaccharides,
disaccharides
Synthetic sweeteners: organic compounds
i.e., Aspartame, Sucralose, Saccharin, AcesulfamePotassium
Acetic acid (vinegar, CH3CO2H); citric acids
(citrus fruits, C(OH)(CO2H)(CH2CO2H)2)
5/03/2024
Further details on food flavours..
• Bitterness: By hydrophobic compounds
(e.g., Chocolate, fruit, nuts, tea and red
wine)
• Saltiness: By table salt (NaCl) and KCl
• Umami: The savory flavour (e.g., Snacks)
• Pungency: The hot, sharp, stinging
sensations associated with hot peppers,
horseradish, onions
Flavonoids; Peptides
Contains MSG and one or both of the
ribonucleotides (5’-inositate and 5’guanylate)
Benzene ring with two ortho substituted
O atoms (i.e., capsaicin, piperine,
gingerol, eugenol)
Esterification of LMW-carboxylic acids
• Esters: i.e., Flavours and odours of fruits
by LMW alcohols
23
Food colours
Perception of colour:
• Interaction of visible light with matter
Organic molecules in food absorb of visible light
• Portion of the molecule that receives the energy is
called a chromophore
• Absorbs the energy and promotes an en to the higher
state
The perceived color is known as the complementary
color of the absorbed color
• Combination of remaining wavelengths
• Natural dye molecules:
– Aromatic and/or highly conjugated
aliphatic hydrocarbons
• Synthetic dye molecules:
– Highly conjugated aromatic systems as
chromophores
24
8/03/2024
Week 2: Food Component
Reactivity and Consumer Benefit
Week 1
Week 2
1
Think about your favourite food
⮚ What could be the chemical or physical changes that has occurred
in this food, which is beneficial for its flavour, texture or nutritional
quality?
Molecular Gastronomy (MG): Sub-discipline of food science that
studies the physical and chemical transformations of ingredients that
occur in cooking
2
8/03/2024
Chemical reactivity in foods producing consumer benefits
Maillard reaction
• Maillard browning involves reactivity between reducing sugars and amines
Reducing sugars + Amines Melanoidins
Glucose
Fructose
Lactose
Lysine
Arginine
Glycine
Maltose
Sucrose
Parameters that affect maillard browning:
Sugar type Amine type Heating time
Temperature pH
3
Further details on Maillard reaction..
• During heat treatment such as frying, roasting, and baking
• Browning of the food’s exterior
• Beneficial Maillard reaction products (MRPs): overall taste, flavour and brown
colour in food
• Potentially harmful MRPs: acrylamide, heterocyclic compounds and advanced
glycation end products (AGEs)
Out of scope: Unfavourable
or excessive Maillard
reaction and associated
effects
4
8/03/2024
Anti-oxidant activity
• Antioxidants: naturally occur or
added to foods
Suppress redox chemistry in food systems;
Preservation effect in food
Oxidant: Chemical species that tends to
oxidize other substances and generate ROS
i.e., Oxidative reactions in foods: Generate off-odors and
off-flavors, color and textural changes, decrease the
sensory and nutritional quality of food
Antioxidants: Molecules stable enough to
donate an electron to a free radical and
neutralize and reduce the capacity to
damage
5
Anti-oxidant activity
Primary antioxidants
Free radical scavengers; inhibit or delay
initiation and/or propagation by donating
en or H
e.g., Phenolic compounds, tocopherols,
synthetic antioxidants (BHA, BHT, TBHQ)
Secondary antioxidants
Indirect mode of action; Decrease the rate of
oxidation by:
– Chelating prooxidant metals
– Replenishing H to primary antioxidants
– Absorbing UV radiation
– functioning as singlet oxygen quenchers
e.g., Ascorbic acid, carotenoids, citric acid,
EDTA
6
Molecular structures:
• Highly conjugated
double bond systems
• highly conjugated
aromatic systems with
– hydroxyl groups (-OH)
– amino groups (-NH)
– thiol groups (-SH)
– isoprenoid groups
8/03/2024
Further details on Anti-oxidant activity..
Usage of natural antioxidants in different food matrices
• Preservation of meat products (e.g., ascorbic acid; essential oils – Rosemary;
Catechins; phenolic acid; tocopherols)
• Preservation of seafood (e.g., phenolic acids and flavonoids)
• Preservation of edible oils (e.g., essential oils of coriander, bergamot, caffeic
acid from coffee)
Usage of synthetic antioxidants
• BHA and BHT: Preserve animal fats
• TBHQ: Preserve vegetable oils and animal fats
• Propyl Galate: vegetable oils, mayonnaise, dried meats
7
Protease activity
• Enzymes that hydrolyze proteins Partial digestion in food proteins (i.e.,
into peptides and amino acids
textural changes in meat)
• Produce from natural plant sources or in vitro techniques:
e.g., papain, bromelain, ficin, actinidin, zingibain, salpichroin, pomiferin, cyprosin, cardosins
Applications:
• Cheese Production: Coagulate milk protein
• Meat Tenderization: Improve sensory properties
• Bioactive Peptide Production: colostrinin peptides protects against AD
• Flour/Dough Modification: Hydrolyse gluten for gluten-free products, modify
dough handling properties and gluten elasticity, increase loaf volume
8
8/03/2024
Caramelisation
• Caramelisation involves reactivity Occurs in the presence or absence of
between sugars; Changes the
catalysts (acids, bases and impurities); in
colour and flavour of food
diluted or concentrated solutions
(amorphous state); and in the crystal form
i)
Sucrose hydrolysis at high
temperature yielding glucose and
fructose
ii) Further degradation of fructose and
glucose
iii) Further removal of water molecules
under heat form brown coloured final
products (caramelan, caramelen,
caramelin)
• Desirable colour and flavour in cofectionary, bakery goods, coffee, beverages, beer and peanuts
• Undesirable effects of caramelization due to burned sugar smell and blackening
9
Physical interactions in foods producing consumer benefits
Gelation
• Gelation is the formation of a 3D
network by chemical or physical
cross-linking
Proteins and polysaccharides:
– Hydrate and dissolve in water
– Set as a semi-solid or solid gel
– Unbound water entrapped by the
protein or polysaccharide matrix
– Form hydrocolloids
• Hydrocolloids: Modify the rheology of food systems (viscosity, texture)
• Simulate the texture and technological properties of solid animal fats
(i.e., low fat sausage and comminuted meats)
• Functional properties: Thickening, gelling, emulsifying, stabilisation, and controlling
the crystal growth of ice and sugar
10
8/03/2024
Further details on Gelation..
Role of hydrocolloids
Examples
Applications
Thickening agents
Starch, modified starch, xanthan, guar gum,
carboxymethyl cellulose (CMC)
Soups, salad dressing, gravy,
ketchup, sauces, cake batters
Gelling agents
Agar, carrageenan, pectin, Gellan gum,
Alginate, Methyl and hydroxypropylmethyl
cellulose
Jelly, dairy desserts, pudding,
jam, glazes
11
Emulsification
• Emulsifier: Surface active agents Emulsification: The process of dispersing two or
with hydrophilc and hydrophobic more immiscible liquids together to combine in a
ends
suspension
• Role of an emulsifier:
Food contains significant proportions of water
and lipid (i.e., O/W food emulsions)
e.g., milk, cream, mayonnaise, salad dressings,
sauces
– Emulsifiers coat the droplets of lipids
and disperse in water
– Prevents phase separation
Food grade emulsifiers: lecithin, soy lecithin, sodium stearoyl lactylate, sodium
phosphates
12
8/03/2024
Sugar ‘foams’ Formation of honeycomb
Addition of sodium bicarbonate to a molten form of sugar form solid foam with
honeycomb structure
– Condensation of sugars
– Thermal decomposition of sodium bicarbonate
– Upon cooling, CO2 gas traps in the sugar matrix and forms the honeycomb
structure
e.g., Honeycomb toffee
13
Rehydrated gluten proteins
Gluten is a structural protein naturally
found in certain cereal grains
(i.e., wheat, rye, barley, cross-breeds)
•
•
14
Composed of gliadin and glutenin
– Hydrate
– Provide visco-elastic properties
– Provides shape, strength, and texture
8/03/2024
Further details on Gluten..
Food applications of gluten as a functional protein
• Visco-elastic properties in bread
• Improvement of cohesiveness and water stability of fish feed pellets
• Reduce the stickiness of pasta
• Hydrolyzed wheat gluten form protein-enriched foods in various flourbased products (i.e., breakfast cereals)
• Texturized wheat proteins
