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The
Mayonnaise & Margarine
Report
For
Dr. P. Alexandridis
CE 457 Colloid & Surface Phenomena
by
Kar-Chan ChoongJoseph Dorsheimer
Barry F. McLaughlinAnthony Zientek
Introduction
Historically, “Mayonnaise is said to be the invention of the French chef of
the Duke de Richelieu in 1756. While the Duke was defeating the British at Port
Mahon, his chef was creating a victory feast that included a sauce made of cream
and eggs. When the chef realized that there was no cream in the kitchen, he
improvised, substituting olive oil for the cream. A new culinary masterpiece was
born, and the chef named it "Mahonnaise" in honor of the Duke's victory”
(http://www.bestfoods.com). On the other hand, “Margarine was created by a
Frenchman from Provence, France -- Hippolyte Mège-Mouriez -- in response to
an offer by the Emperor Louis Napoleon III for the production of a satisfactory
substitute for butter. To formulate his entry, Mège-Mouriez used margaric acid, a
fatty acid component isolated in 1813 by Michael Chevreul and named because of
the lustrous pearly drops that reminded him of the Greek word for pearl --
margarites. From this word, Mège-Mouriez coined the name margarine for his
invention that claimed the Emperor’s prize” (http://www.margarine.org.) The
purpose of this research paper is to provide an extensive, scientific look into the
world of mayonnaise and margarine.
Standards of Identification
Mayonnaise
When classifying a food product by name it must contain a standard set of
ingredients put forward by the Food and Drug Administration. There can be substitutes
for certain ingredients with others but these must be on the list that is provided by the
FDA. Each of these ingredients is required to be written on the label, for all consumers
to view. This is how the nomenclature for each food product is given
(http://www.accessdata.fda.gov).
Mayonnaise is an emulsified semisolid food that is made with vegetable oils.
This is not limited to just vegetable oil however; sunflower oil, Soya oil, and rapeseed oil
may also be used in making mayonnaise. No mineral oil may be used in the preparation
of mayonnaise.
One or both of the following acidifying ingredients must also be used in the
preparation of mayonnaise. These acidifying ingredients are any vinegar or any vinegar
2
diluted with water to acidity, of no less than 2.5% by weight, calculated as acetic acid, or
any type of vinegar or diluted vinegar that is combined with an extra acidifying
ingredient that is listed in the following section. Salt and nutritive carbohydrate
sweeteners are two of these ingredients. Any spice or natural flavoring may also be used
as long as it does not change the color of the mayonnaise to a color, which is given by
egg yolks. Saffron and turmeric may not be added to mayonnaise. Monosodium
glutamate and Sequestrant(s) may also be used in the preparation of mayonnaise. These
Sequestrants can be one of the following; calcium disodium EDTA (calcium disodium
ethylenediamine- tetraacetate) and/or disodium EDTA (disodium
ethylenediaminetetraacetate). Other Sequestrants may also be used. Sequestrants are
used to preserve the color and the flavor of the mayonnaise. Other acidifying ingredients
are citric and/or malic acid. These ingredients may be added in an amount that is no
greater than 25% of the weight of the acids of the vinegar or diluted vinegar. This must
be calculated as acetic acid. The last acidifying ingredient that may be added is the
crystallization inhibitor. These can include lecithin, polyglycerol esters of fatty acids,
and oxystearin. Other crystallization inhibitors may also be used. When talking about
vinegars in this paragraph any mixture of two more vinegars can also be considered
vinegar (http://www.accessdata.fda.gov).
The next ingredients that may be added are lemon juice and/or lime juice.
These can be added in a type of mixture, which can be diluted with water to an acidity, of
no less than 2.5% by weight. This acidity must be calculated as that of citric acid. The
final ingredient that must be added before it can be officially called mayonnaise is the
egg yolk-containing ingredient. The following type of egg yolks may be added to the
mixture: frozen, dried, and liquid. The following types of whole eggs may also be added:
liquid, frozen, and dried. Also any of the previous egg containing ingredients can also be
mixed with liquid and or frozen egg whites. This final addition of eggs will give the
name of this mixture as mayonnaise (http://www.accessdata.fda.gov).
3
Suppliers
There are many suppliers of mayonnaise throughout the country. One such
supplier is Kraft Foods. They market their product with the same name. Kraft
mayonnaise can be found on the shelves of almost every supermarket. Unilever is
another large food supplier, which markets their mayonnaise under two different names;
one of which is Hellmann’s and the other which is Best Foods. They are essentially the
same product only Hellmann’s is found east of the Rocky Mountains, and Best Foods is
found strictly on the west coast. Another supplier of mayonnaise is Better Brands. They
can be found primarily in New England and New York. Their brands include; Allen and
Nugget. The Shurfine brand has a number of separate labels, which distribute different
varieties of mayonnaise. Some of their product lines include; Shurfine, Ultimate Choice,
Shurfresh, Saver’s Choice, and Price Saver. They all have different types of mayonnaise
in their product lines. These are just some of the many varieties of mayonnaise, which
can be found in stores today. There are many smaller brands and store brands which can
be found in specific geographic areas.
Standards of Identification
Margarine
Margarine can be described as a liquid emulsion or a food in the plastic form. It
must contain no less than 80% fat as determined by the “Official Method”, used the by
the “Official Analytical Chemists”. Margarine must contain one or more of the
ingredients in the following three paragraphs to be considered margarine.
The first such section of ingredients is the edible fats and oils, or any such
mixture of these. These fats and oils must have an origin or vegetable or rendered animal
carcass fats. Also any type of oil that has been extracted from any marine species and has
been listed as GRAS, or a food additive may be used. An accepted process of physico-
chemical modification may alter these oils. The oils may have small traces of lipids, and
free fatty acids that can be found naturally in the fat or oil
(http://www.accessdata.fda.gov).
The next such set of ingredients that must be used is the aqueous phase
ingredients. One or more of these aqueous phase ingredients may be used in the
4
preparation of margarine. The first set includes water, water and milk, or just milk
products. The next set is the edible proteins; these can include the liquid, dry or
condensed form of whey. The whey may be changed by the reduction of lactose and
other minerals. The use of no lactose components as well as vegetable proteins, casein,
albumin, and soy protein isolate may also be used to modify the whey. The amount used
must be no greater than a reasonable amount to achieve the desired product. These
ingredients are then subject to a pasteurizing process and then introduced to harmless
bacterial starters (http://www.accessdata.fda.gov).
The previous set of aqueous phase ingredients may be combined with either one
or more of the following ingredients. Vitamin D may be added to the mixture as long as
there are 1500 international units of Vitamin D per pound of margarine. Sodium
Chloride or Potassium Chloride may also be added to the ingredients. Emulsifiers and
nutritive carbohydrate sweeteners are two more ingredients, which can be added to the
aqueous phase ingredients. Preservatives may be added to margarine in varying amounts.
Some of these preservatives and their amounts are listed here. Benzoic and Sorbic acid,
and sodium, potassium, and calcium salts may be used. If used individually they can
account for .1%, if combined .2%. EDTA can also be used in an amount of .0075%. The
following gallates can be used: propyl, octyl, and dodecyl. These can be used separately
or combined with BHA, BHT, ascorbyl stearate, and ascorbyl palmitate, at a .02%
mixture. The last two preservatives that may be used are stearyl citrate, and isopropyl
citrate. The respective amounts used are .15% and .02%. The color additive that can be
used in margarine is beta-carotene. Acidulants and Alkalizers are also optional
ingredients in margarine. Flavoring substances may be used. If they change the taste so
that it does not taste like butter, the change has to be noted in the naming of the
margarine. If all these rules are followed then the substance created can be officially
named margarine (http://www.accessdata.fda.gov).
Suppliers
There are various brands of margarine, as well as numerous varieties of each
brand. One such supplier of margarine is ConAgra Foods. They supply Fleischmann’s,
Parkay, and Blue Bonnet. These brands are run by the Nabisco Tablespreads Company,
5
which also has the products, Touch of Butter, Chiffon, and Move Over Butter brands of
margarine. Another very popular brand of margarine is the I Can’t Believe It’s Not
Butter line. They have various varieties including regular, light, sweet cream and
calcium, spray, squeeze, fat free, and unsalted. ADM is another supplier of margarine,
which uses the label Gold’N Flavor to sell its product. They also have varieties, which
range from table grade, to bakers roll, to liquid grade margarine. Ventura Foods is
another supplier of margarine, which promotes its products through the name Saffola.
Their varieties include; real, soft, reduced fat, unsalted and safflower margarine. Shedd’s
Spread Country Crock is another brand of margarine, which has various varieties such as
regular, light, and churn style. Land O’ Lakes is another brand of margarine with various
varieties. There are many varieties of margarine throughout the country. Nearly every
supermarket carries their own specific variety as well as those from large food
distributors such as ConAgra Foods.
Food Chemistry Behind Mayonnaise & MargarineAs previously stated, the organic/food chemical ingredients of mayonnaise and
margarine have very solid general basics. However, each manufacturer of the respective
food product has modified the “Standard of Identification” requirements to include
ingredients to make their products unique compare to their competitions. The products
selected to analyze food chemical ingredients were Hellmann’s® Real Mayonnaise,
Hellmann’s® Just 2 Good Reduced Fat Mayonnaise, and Blue Bonnet Regular
Margarine. The ingredients are listed in order of decreasing amounts.
Composition of Regular Mayonnaise
Hellmann’s® Real Mayonnaise consists of soybean oil, whole eggs, vinegar,
water, egg yolks, salt, sugar, lemon juice, natural flavors, and calcium disodium EDTA.
Soybean oil is typically composed of pure, edible, vegetable oil with no carbohydrates,
cholesterol, fiber, protein, sodium or sulfites. It has the following unsaturated fatty acid
(CH3(CH2)xCOOH) composition: 0.1% Myristic (C14), 10.6% Palmitic (C16), 0.1%
Margaric (C17), 4.0% Stearic (C18), 0.3% Arachidic (C20), and 0.3% Behenic (C22).
The remaining composition is made from saturated fatty acids (carbon length: number of
6
double bonds): 0.1% Palmitoleic (C16:1), 23.2% Oleic (C18:1), 53.7% Linoleic (C18:2),
and 7.6% (C18:3). Soybean oil is an emulsifying agent that is produced by such
companies as Karlshamns® Inc. (PDB 1).
Whole eggs, at best, are described in general terms. They consist of fats, proteins,
mineral salts, and water, everything except oxygen necessary for the forming of a chic.
As a result, “we are still adding to the list of chemical compounds which an egg contains”
(Jacobs 995). Approximately per 100 g of whole egg includes: 24.68 g solids, 12.50 g
protein (polyaminoacids), 10.02 g lipids (fatty acids) and 1.22 g carbohydrates
(polysaccharides) (PDB 2). The diverse composition allows the whole eggs to play
emulsifier and emulsifying roles in mayonnaise. They can be found at companies ranging
from your local farmer to the Global Egg Corporation.
Vinegar is typically composed of 5% acetic acid, CH3COOH, and water. It is
produced by successive alcoholic and acetous fermentation of cider, grapes, sucrose,
glucose or malt (Furia 248). It is classified as an acidulent, which is a multi-purpose title
given to an ingredient that acts as a flavor agent, pH buffer, preservative, antioxidant
synergist, and/or viscosity modifier in mayonnaise (248). It can be sourced from
companies such as Indian Summer.
Water, H2O, serves the hydrophilic side of the emulsion. It is the emulsifying
agent that must be homogenized with it hydrophobic counterpart. The metal content of
the water must be controlled through use of chelating agent to prevent off flavors in the
mayonnaise.
Egg yolk’s chemical composition, like whole eggs, can only be explained in
general terms. Egg yolks minimally consist of 56% fat (lipids) and 30% protein. It’s an
emulsifier that also acts a coloring agent to the finished mayonnaise product (521). This
product is found in a dry solid form and is available from Julius Goldman’s Egg City
(PDB 3).
Salt, NaCl, is used as a preserving agent. The supplier IMC® Salt produces it by
“industry standard solution mining and evaporation process, where the salt is washed,
filtered, dried, screened, admixed and quality control tested” (PDB 5). The “sugar” used
in mayonnaise is comprised mainly of the disaccharide sucrose C12H22O11. A flavoring
7
agent used in mayonnaise, it can be purchased from sugar refiners such as Colonial
Sugars Inc.
Lemon juice is used in mayonnaise to complex harmful metal pro-oxidants in
addition to adding desirable acidity. Sunkist Growers, Inc produces this juice “from
selected lemons that are fine screened, centrifuged, stabilized, concentrated, and
packaged without preservatives” (PDB 7). Natural flavors are the flavoring agents
provided by the above ingredients.
Finally, calcium disodium EDTA, (C10H16O8N2)-Ca-Na2, is a chelating agent
which acts like a sequestrant in assisting anti-oxidant systems. For mayonnaise, it assists
in stabilizing the soybean oil, extends shelf-life, retains flavor, and inhibits the oxidation
of undesirable coagulation caused by the pre-freeze heat sterilization of whole eggs
(Furia 305).
Composition of Low-Fat Mayonnaise
Hellmann’s® Just 2 Good Reduced Fat Mayonnaise consists of water, soybean
oil, modified corn starch, sugar, egg whites, vinegar, salt, cellulose gel and gum, natural
flavors (contain mustard), color added, xanthan gum, sodium benzoate, and calcium
disodium EDTA. The ingredients used in both mayonnaises serve the similar roles and do
not merit repeating.
Modified corn starch, 100% amylopectin (-O-C6H8O2-O-C6H8O2-O-)x, is
“produced by modifying corn starch from waxy maize with proplyene oxide and
crosslinking it with phosphorous oxychloride” (Maiolino Interview). It is classified as a
thickening agent, which provides “back texture and viscosity” (Maiolino Interview).
National Starch and Chemical Corporation produce this gum. Egg whites minimally
consist of 12% solids, 10% protein, and 0.03% fat (PDB 9). They are collectively referred
to as albumen and are classified as food binders by Maple Lynn Foods.
Cellulose gel and gum are common synonyms for carboxymethylcellulose
(CMC). It has a general chemical formula of (C6H10O5)x. The CMC that forms a trivalent
cation with such metals as aluminum is considered gel while CMC forms with a mono
cation like sodium is considered a gum (Furia 339). Both are produced by cellulose
treated with NaOH that later reacts with a metal-type monochloroacetic acid, and is
8
washed with an alcohol-water mixture to remove salt (339). These gums are protective
colloid uses as a thickener, suspender, stabilizer, and replacement for fat (PDB 11). They
are soluble in hot or cold water and may be purchased from companies like Hercules
and FMC (11).
Mustard “presumably operates as a finely-divided solid in the stabilization of
mayonnaise”(Becher 346). It is a pungent, sharp, modifier that exhibits fair stability in
mayonnaise (Furia 482). Xanthan gum is a cold soluble, hydrophilic, colloid that is
produced by the bacteria, Xanthomonas campestrs (PDB 12). The chemical structure,
(C35H49O29)n, is “composed of a backbone of glucose units with trisaccharide side chains
(two mannose and one glucuronid acid residues) which are regularly positioned at
alternating glucose units (12). Xathan gum is used “at a level of 0.2%-1% in mayonnaise
to provide stability, mouth feel and cling, and flavor release” (PDB 13).
Sodium benzoate, C6H5COONa, is a low-cost preservative that is active against
yeast, bacteria, and to a lesser extent mold (Furia 142). It has a synergistic effect with salt
and in sued at about 0.05%-0.1% in products (143). This ingredient is available from
Kalama Chemical, Inc.
Composition of Margarine
Blue Bonnet® Regular Margarine consists of soybean oil, partially hydrogenated
soy oil, whey, salt, mono and diglycerides, soy lecithin, potassium sorbate, sodium
benzoate, phosphoric acid, vitamin A palmitate, artificial flavor, beta carotene.
Duplication of ingredients and there similar functions in both mayonnaise and margarine
do not require repetition.
Partially hydrogenated soybean oil has a fatty acid composition of 23% saturates,
72% mono-saturates, and 5% poly-saturates (PDB 15). It is mainly used as non-dairy
substitute and can be classified as an emulsifying agent. Central Soya in Indiana
produces this ingredient. Whey is primarily composed of water, solids, protein, lactose
(disaccharide of galactose), and ash (Winton 195). It can “contribute significantly to
flavour, appearance, texture, structure, and shelf stability” (PDB 16). Mono
((CH2)2CH(OH)2(COOR)) and Diglycerides ((CH2)2CH(OH)1(COOR)2), are food grade
emulsifiers derived from vegetable oils. They are composed of alpha-mono, beta-mono,
9
di- and tri-esters of mixtures of fatty acids. Used in low levels, this ingredient improves
stability of vegetable fat and water during storage of margarine (Furia 431). This
produced can be purchased from such companies as Loders Croklaan.
Soy Lecithin, C3H5(COOR)2POOOC5H14N, is also available from Central Soya.
It is a phospholipid emulsifier that is produced when triglycerol is esterified with a fatty
acid and phosphoric acid. The phosphoric acid branch later combines with a nitrogen-
containing compound (213). It also serves as a wetting agent in margarine.
Potassium Sorbate, CH3(CH)3COOK, is a white, fluffy powder that is water
soluble. It is an effective preserve at low concentration for control of mold and yeast
(151). Phosphoric acid, H3PO4, is used as acidulation agent in margarine. It is the only
extensive inorganic acid used (268).
Vitamin A Palmitate, C36H60O2, is as an anti-oxidant and used to fortify and help
stabilize margarine (PDB 21). Beta-Carotene, C40H56, is a brick-red viscous oil used as a
coloring agent/nutrient for margarine (21). Both of these products are available from
Roche Vitamins Inc.
Analytical Methods to Determine Composition
There are specified methods to determine chemical compositional properties of
mayonnaise and margarine. For mayonnaise, these tests include total solids by vacuumed
oven, total fats by Mojonnier, total nitrogen by Kjeldahl, total phosphorous by
evaporation, egg content, total acidity by titration, emulsion stability over time, specific
weight and gums by copper reduction (Fisher and Hart 355). For margarine, these tests
include moisture by oven drying, fat by digestion and filtration, and salt by titration
(128).
Basic Emulsion Theory
An emulsion is a homogenous mixture of oil and water that is stabilized by an
emulsifier (Stokes, 205). Many compounds considered to be emulsions, such as sauces,
are fat (oil) and water, but that is not a requirement. There are two classifications of
emulsions, microemulsions and macroemulsions. Microemulsions are thermodynamically
stable and are usually clear solutions. Macroemulsions are not thermodynamically stable
10
and will eventually separate into an oil rich phase and a water rich phase (Stokes, 205).
Significant amount of mechanical energy required in the emulsification process to
disperse one of the liquids in the form of small droplets in the continuous phase. Janssen
and Meijer describe the emulsion process in three stage based on the value of capillary
number.
In the equation above, ηc is the viscosity of the continuous phase, γ is the shear rate and σ
is the interfacial tension and R the radius of disperse phase droplets. The capillary (Ca)
number and Reynolds number (Re) decrease in the emulsification process due to the
increase in viscosity and reduction of the length scale. In the first stage of emulsification,
the dispersed drops stretch; Ca is much higher than critical value, Cacrit, local stress
overrules the interfacial stress. “This mechanism is typically produced at the beginning of
the process and leads to formation of large liquid threads. In the second stage, threads
and drops consecutive breakup which take place when Ca > Cacrit. In the last stage,
coalescence of the disperse droplets occur when Ca is smaller or equal to Cacrit.
The two critical steps in emulsification are the consecutive disruption of droplets
and their coalescence, both of which are favored by an intense agitation. The evolution of
this process as well as the microstructure of the final emulsion depends on many
variables related to the processing conditions such as type and geometry of the
emulsification equipment, residence time, agitation speed, temperature of emulsification
or to the nature of the phases involved.
The most important property of a given emulsion is its stability. An emulsion is
stable, from kinetic point of view, when the number, droplet undergo any discernible
change over the storage time scale. If it is not stable, then the mixture could phase
separate leading to product failure. Emulsion rheology and stability are closely related to
several structural parameters. One important aspect of stability is interfacial tension.
When an emulsion is formed, the interfacial tension increases. This, in turn, increases the
likelihood of the mixture separating. An emulsifier is added to decrease the interfacial
tension, and make the mixture less separated. The net interaction between the dispersed
molecules can be found by the adding the van der Waals forces of attraction and the
11
electrostatic force of repulsion. If the attractive force is greater than the repulsive force,
the mixture is unstable. If the repulsive force is greater than the attractive force, the
mixture is referred to as stable. If more stability is required, fine particles or
macromolecules can be added to the mixture. These species will adsorb to the interfacial
boundary and form a physical barrier around the droplets.
An emulsifier is typically required to improve of the emulsification process and
emulsion stability. There are two important roles of emulsifier molecules during the
emulsification process. First, “they adsorb at the o/w interface, which reduces the
interfacial tension, yielding a decrease in the amount of mechanical energy required to
deform and disrupt the droplet and thereby favoring emulsification” (Sanchez et al.). In
the case of high surfactant concentration and low interfacial tension, by inducing strong
interfacial tension gradient “spontaneous emulsification” will occur. Secondly, emulsifier
prevents recoalescence. This effect is called Gibbs-Marangoni effect and caused by
formation of interfacial tension gradients during emulsification. This effect is described
as formations of a protective barrier around the oil droplets, which provide a repulsive
force to prevent droplet from aggregating with each other. Typical emulsifiers often
have the qualities of an amphiphilic molecule. The functionality of the emulsifier is a
result of the chemical structure. A typical emulsifier consists of two parts, a hydrocarbon
chain that is lipophilic and a hydrophilic polar group. Fine particles are often used to
stabilize emulsions that contain oil-water interfaces. The efficiency of emulsifier
molecules are strongly depends on the ability to enhance the interfacial rheological
properties of emulsion droplets and the kinetics of adsorption to the interface. Under
same homogenization condition, emulsifiers, which adsorb rapidly, produce smaller
droplet sizes than those absorb slowly. Most of the food emulsifiers do not absorb rapidly
enough to completely prevent droplet coalescence. There are three major classifications
of emulsions. They are temporary, semi-permanent and permanent. An example of a
temporary emulsion is oil mixed with vinegar. An example of a semi-permanent
emulsion is pourable salad dressing. An example of a permanent emulsion is
mayonnaise.
12
Regular Mayonnaise Formulation
Mayonnaise is primarily a mixture of oil, egg, a water based acid and spices for
flavoring. Typically, in regular mayonnaise, the oil accounts for approximately 75% or
more of the total volume (Depree, 157). Traditional mayonnaise is considered to be an
oil-in-water emulsion even though it contains 70-80% fat and oils (Depree, 157). The
two most common water based acids are vinegar and lemon juice. The important
ingredient in the manufacturing of regular mayonnaise is the egg yolk that is added. The
egg yolk consists of a soluble plasma fraction where low density lipoproteins (LDL)
predominate and a particulate granule fraction consist of highly HDL with a highly
charged phosphorylated phosvitin. “The presence of hydrophobic and hydrophilic
proteins as well as phospholipids and cholesterol is believed to be responsible for the
excellent emulsifying properties of egg yolk.” (Aluko et al.) The other ingredients are
added for flavor and only minimally contribute to the interfacial chemistry of
mayonnaise.
Some of the more active molecules include lecithin, lipovitellin, lipovitellinin and
livetin (Depree, 158). All these components are thought to be active contributors to the
quality of the emulsion; however, the most important emulsifying agent is lecithin.
Lecithin is found in the egg yolk and also in the soybean oil that is added. It embeds itself
into the water droplets in the mayonnaise and prevents them from clumping together.
The functional component of lecithin is a mixture of phospholipids
(http://www.foodproductdesign.com/archive/1995/1095DE.html). Phospholipids, similar
to basic emulsifier structure, contain a hydrophilic polar head. Unlike the basic structure,
the lipophilic portion contains two fatty acid tails. It has been shown that the adsorption
of lipoproteins to the oil water interface occurs in three stages (Kiosseoglou, 502). The
stages are diffusion of native protein molecules to the interface, penetration of the
interface by these molecules and rearrangement of the adsorbed molecules to achieve the
lowest free energy state.
The basic emulsion addition pathway is as follows. First the vinegar is mixed
with the emulsifying agents. After that, the oil is added slowly to the mixture followed
by the addition of stabilizers and preservatives. Finally, the spices and flavor agents can
be added after the emulsion is complete. The result of properly mixing is an emulsion
13
consisting of closely packed ‘foam’ of oil droplets (Depree, 157). If the oil and water
based phases are mixed together at once, or if the oil is added to quickly, the result will
be a water-in-oil emulsion with similar properties of the oil that was used (Depree, 157).
There will be a point when the mixture will coalesce, or break up, into the water rich
phase and the oil rich phase. If phase separation occurs, too much oil has been added to
quickly to the mixture.
In an ideal emulsion, consisting of spherical shaped droplets in a bulk phase, the
dispersed droplets can only account for a maximum of 74% of the volume (Depree, 157).
As stated above, in mayonnaise the dispersed phase accounts for 75% or more. This
leads to the oil droplets being distorted from their normal spherical shape. The close
packing of the droplets allows them to interact more with each other than they would
usually. This contributes to the viscosity of regular mayonnaise.
Salt can be added to the final mixture to improve the characteristics of
mayonnaise for three reasons. First, the salt particles help to disperse the egg yolk
granules to make more surface-active material available. Second, the added salt will
neutralize any charges that are found on the proteins. This will allow the proteins to
adsorb to and strengthen the existing layer on the oil droplet. Last, the neutralization of
any charge allows the oil droplets adjacent to each other to interact more strongly
(Depree, 158).
The other ingredients added to the mixture have different affects on the
interaction of the droplets. The sucrose that is added tends to weaken the interactions. It
does this by shielding the reactive groups contained in the mixture. Proteins found in egg
whites and carboxymethyl cellulose will interact with the proteins found in the egg yolk
and form cross-links between the droplets (Depree, 159). Modified starches are also
added to increase the stability of the emulsion (Deis, 100). Modified starches contain a
mixture of amylose and amylopectin. Besides, the interfacial film formed between the
yolk protein and oil-in-water interface is strongly related to the medium condition such as
pH, ionic strength and protein concentration. Mayonnaise is prepared less than pH 4.5.
Studies of Anton et al. shows at pH 3, the oil droplet is around 11.8μm and proteins at
interface are mainly phosvitin.
14
Low Fat Mayonnaise Formulation
Low fat mayonnaise is produced by the same basic mechanism that regular
mayonnaise is produced. Some other ingredients are added to achieve the low fat
requirement. The biggest difference in the two recipes is the use of eggs. In low fat
recipes, the egg yolks are replaced with the egg whites. This decreases the amount of
cholesterol added to the product and results in a “lighter” product. However, this poses a
problem for the interfacial chemistry of the mixture. The emulsifiers found in the egg
yolk are not as abundantly found in egg white. For this reason, other emulsifiers must be
added to achieve the emulsion properties.
Additional lecithin is added through the addition of soybean oil. Another
emulsifier that can be added to the mixture is finely ground particulate mustard. The
mustard particles imbed themselves into the oil-water interface similarly to the lecithin.
The mustard particles embed themselves into the water droplets and block the oil and
water from coalescing. Another emulsifier added to the mixture is xathan gum. It acts as
both an emulsifier and a thickener (www.xanthan-gum.net).
The general addition procedure stays the same with low-fat mayonnaise and
regular mayonnaise. The steps can be seen above for reference. Once the egg whites and
soybean oil is added to the water, the oil can be whisked in gradually. Once the proper
amount oil has been added, the stabilizers, preservatives and seasonings can be added.
Preservatives for low fat mayonnaise include calcium disodium EDTA, salt and sodium
benzoate.
Low- fat Mayonnaise Cholesterol Extraction
In order to produce lower cholesterol mayonnaise, reducing cholesterol content of
egg yolk is crucial. Organic solvents or supercritical CO2 are the effectual methods to
remove cholesterol from yolk. However, the substitution of yolk with other functional
ingredients in food formulation impairs the flavor and mouth feel of a product.
“The stability and textural properties of highly concentrated emulsions such as
mayonnaise depend to a great extent on the presence of whole egg or egg yolk
constituents which stabilize the oil droplets against coalescence while at the same time
are involved in complex interactions with the emulsion oil droplets resulting in the
15
formation of a network that emulsion and especially its viscoelasticity” (Paraskevopoulou
et al.). The yolk composition could be distorted and the protein could be denatured after
cholesterol extraction. Selective method for this purpose is critical. Studies have found
supercritical CO2 is more selective in extracting cholesterol from yolk. Nevertheless, it
result a higher phospholipids compare with the concentration prepared by ethanol/water
extraction. On the other hand, the yolk extracted with an ethanol/water mixture exhibited
higher viscoelastic moduli value. Results from the study also have shown mayonnaise
prepared with spray dried yolk contains a lower amount of protein than the two emulsions
prepared by the supercritical CO2 extraction and ethanol/water extraction, as a result of
the lower amount of protein, it gives a lower viscoelasticity but highest stability when
aged for a certain period of time. The modulus studies of these samples conclude the
protein concentration influences the viscoelasticity. Mayonnaise may be characterized as
“weak” gel, which yields under strain sweep experiments. The yield point is the function
of the type of yolk used during the preparation.
Margarine Formulation
An emulsion is fine dispersion of one liquid in a second largely immiscible liquid.
In food emulsion like margarine, the liquids are always an aqueous solution and liquid
oil. Margarine has complex colloids containing mixed dispersed phases and some
crystallization may be occurred. As well known, emulsion formation requires a large
energy input. This usually achieved with a high-speed mixer or valve homogenizer.
In an emulsion, there is always one phase that is continuous and another that is
dispersed (the droplets). For margarine, the aqueous phase is continuous, so it is oil in
water (o/w) emulsion. Emulsions behave most similarly to their continuous phase. That is
the reason margarine feels greasy like oil and easily disperse in more oil.
In general, smaller emulsion droplets offer a more stable emulsion. However,
higher energy is required to reduce the size (and higher surface areas) of droplets in
emulsion. Typically in industrial production, the droplets size is around 300nm. Particles
larger than 2 or 3mm are unfavorable and have limited stability.
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Viscosity of margarine is a strong function of concentration of droplets. A high
concentration of droplets causes an increase in viscosity and eventually the development
of solid –like character.
In margarine process, the oil surfaces in aqueous continuum are energetically
unstable because of the hydrophobic effects or formulated as the surface excess free
energy. Margarine surface-active polymers accumulate at the surface to provide some
stability to the emulsion by covering the surface and development of repulsive colloidal
forces. An emulsion behaves like its continuous phase, so any material added to the
continuous phase will affect perceived properties of the emulsion. In margarine, by the
addition of viscosity- reducing hydrocolloids to the dispersed phased to thinker the
product is a crucial step. Any additive can cause the protein aggregation and lead to
emulsion destabilization due to flocculation if the protein is bound to the surface of an
emulsion. As a result, changes in pH in addition of favor like salt and the action of
proteolytic enzymes maybe destabilize emulsion.
Emulsion like margarine is always thermodynamically unstable structures given a
limited lifetime by addition of surface-active material. Consequently, the properties will
continuously change towards the equilibrium position of oil floating on top and of an
aqueous solution. As the density of the continuous and dispersed phases is different, they
will separate under gravity, e.g solid fat crystal in liquid oil sediment out to the bottom of
the container. Another important properties of emulsion, in the case the margarine are the
process of flocculation and coalescence. Flocculation is the process of two particles
coming into semi-permanent contact without merging. Coalescence involves complete
merging to the particles. Flocculation often occurs before coalescence and the merging of
the particles happen subsequently. Flocculation causes an increase of viscosity and forms
a continuous 3-D network throughout the container. Fast flocculation leads to the
formation of large open flocs as the particles tend to rapidly adhere at the position of first
contact. During the slow flocculation the droplets will form a more dense flocs. Most
dispersed systems are prone to flocculation and coalescence to a greater or lesser extent
because both processes lead to reduction in interfacial area.
Margarine is made from vegetable oils, which contain unsaturated carbon.
Hydrogenation of these oils at 170°C using a nickel catalyst saturates the carbon chains;
17
this raises the melting point of the oils so that they become solid (crystallize) at room
temperatures.
During the process manufacturer has to make sure the fat blend have high liquid
oil content, little or no hardened fat, substantially no trans-unsaturated fatty acid content
and a relatively low level of saturated fatty acids. Margarine fat should be used having a
well-balanced ratio of liquid and solid fats throughout the entire area and use
temperatures, which usually is from 5°C to about 20°C.
In the past, natural fats are used to blend with the margarine mixture to maintain
sufficient solids content. However, the result in products is unsatisfactory spreadability,
consistency and mouth feel. The use if mixtures of fat hardened to different degree of
saturated fat is an alternative way to achieve the desired “hardness”. Due to the
nutritional reason, the level of saturated fatty acid (SAFA) of the component triacyl
glycerides of the fats should be minimized.
Analytical methods to Determine Colloid Properties
Rheology of mayonnaise is of great importance and its correct evaluation can
provide valuable information that can be used in quality control of commercial
production, storage stability, sensory assessments of consistency, knowledge and design
of texture, design of unit operations, and knowledge of the mechanical processing on the
structure of emulsion (Davis). For example, the studies of rheology of mayonnaise
concluded that a high oil content and presence of stabilizer increase the complexity of the
structure of emulsion. While the presence of gum in mayonnaise as stabilizer, the
emulsion is less sensitive. When the oil content in mayonnaise increased, the amount of
irreversible structural breakdown is increased. Gallegos et al. experiment in mayonnaise
suggested that structural recovery is associated with an elastic recovery of deformed flocs
(instantaneous recovery) and the reflocculation of oil droplets (time dependent recovery).
Numerous of semi-liquid foods materials such as mayonnaise or peanut butter reveal
viscoelastic properties that result in stress overshoot in constant shear rate viscosity
measurements. “The significance of this phenomenon is primarily in the sensory
perception of such products’ consistency, which is based on transient flow regimes in the
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mouth and also in certain industrial operations such as mixing and pumping.”
(Campanella et al.
Previously, transient viscoelastic flow occurs in polymers is used to describe
mayonnaise flow by Bird-Leider equation:
Where = shear stress
K and r = power law constants
= Shear rate
= Characteristic time constant
a and b = empirical constants
However, this four-parameter empirical model has one exponential decay term, which is
derisory for viscoelastic fluid with a wide spectrum of relaxation times.
Campanella and Peleg proposed a model slight modification of a model
developed by Larson for polymer melt with wide molecular weight distribution to
describe the transient flow of mayonnaise. This model has three parameters and gives
sensible description of the stress overshoot phenomenon. The model appears to give a
better account of the real behavior of mayonnaise than the Bird-Leider equation.
The (m) is gamma function. Details of the equation can be found in Campanella et al.
Numerous rheometrical studies of mayonnaise have been studied and have
highlighted complex flow phenomena exhibited by the material. “Indeed, mayonnaise has
been shown to be shear thinning, viscoelastic, and thixotropic, it has yield stress, and in
some studies apparent wall slip has been observed” (Goshawk et al.).
Production & Processing at the Plant LevelFor plant production and processing of mayonnaise, two companies, Waukesha
Cherry-Burrell and Bran-Luebbe supply the necessary equipment. According to the
Waukesha technical literature:
Powdered egg and spices are dissolved in a mixer, cooled in a plate heat exchanger then stored in a jacketed tank prior to blending. Vegetable oil is also
19
cooled in a plate heat exchanger prior to blending. Vinegar, the chilled oil and the chilled egg mixture are supplied to a continuous blending system, which consists of a multi-head metering pump and a pre-emulsion mixer. The metering pump insures that the various ingredients are fed in the correct proportions. The mixer blends the ingredients together and prepares them for finishing in the WCB colloid mill, which creates a uniform dispersion and stable emulsion. The product then flows to the filler. An optional tank acts as a filler feed buffer if the filler does not have an inlet tank or if garnish is added. (www.gowcb.com)
Bran-Luebbe describes the process as, “the mayonnaise ingredients are pump into suction
vessels and the ingredient levels in the vessels are controlled by level probes and
throttling valves.” Also a “metering pump proportions and pumps the ingredients through
a back pressure valve into a pre-emulsifier.” The “resulting emulsion is pumped out of
the emulsifier and into a colloid mill with the finished product sent to a filler buffer
tank”(www.bran-luebbe.com). During this process, “the quality control tests performed
on the product including Salt, T.A, Viscosity, pH, density, and Micro” (Fendinger
Interview).
Mayonnaise packaging started in 1905 when Richard Hellmann “began selling it
in "wooden boats" that were used for weighing butter” (http://www.bestfoods.com).
Today, mayonnaise is typically packaged either in non-sterile glass or PET (-O-CO-
C6H6COO-(CH2)2-)x) jars (www.seps.org). Operators “hand-dump” the jars onto the
process line where “ they are flipped and air is forced into them to clean any packaging
particulate” (Fendinger Interview). The containers are then “righted, filled and capped
before being boxed as a finished product” (Fendinger Interview). Regular mayonnaise is
available for sale once the microbiological tests have been completed. Besides micro
results, low-fat or reduced mayonnaise must be allowed a day to “set” at ambient
temperatures before it can be made available for sale (Fendinger Interview).
Product Processing For Margarine
The processing equipment needed to make margarine can be built by a number of
different companies. The Waukesha Cherry-Burrell process will be the main focus of
this part. The first pieces of equipment needed for this process are separate raw material
tanks for the holding of the milk, concentrated emulsifier solution, brine, and margarine
oils. This allows for the proper blending of ingredients, which ensure the correct
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emulsion. This is then fed to an emulsion feed tank where it is pasteurized using a WCB
plate heat exchanger. Inside the pasteurizer there are separate heating and cooling
sections. Inside there also contains a separate regeneration section to reclaim part of the
energy put in. A high pressure pump then moves the emulsion to Votator® scraped
surface heat exchangers that have controls which monitor temperature, and power sensors
which help to prevent the freezing of this product due to overcooling. This emulsion is
crystallized, plasticized, and conditioned. Votator® agitated holding units are used when
filling tubs or bulk filling. Votator® quiescent holding tubes are then used when stick
molding or sheet printing is done. WCB heat exchangers are also used in the end of the
process to melt overfeed and return it to the pasteurization system
(http://www.gowcb.com).
For mayonnaise and margarine production, the main concern is safety and
contamination. It is expected that the operator(s) should be following good manufacturing
practices (GMPs) when they make their respective product. This means that safety boots,
goggles, lab coats, and other necessary apparatus need to be worn. Also, the equipment
must be cleaned and sterilized both before and after shut down of the respective machine.
Margarine can be packaged in a number of different ways. They can be packaged
into large commercial tubs, smaller consumer tubs, small and large stick margarine, and
now some are even packaged as sprays. Generally, tub margarines are mechanically
worked this allows for crystal growth. It also prevents the formation of a firm crystal
lattice. The longer the product is work the more the consistency softens. Stick margarine
is produced by extrusion of chilled product into forming moulds and then they are
wrapped and placed into boxes. It is important to allow the stick margarine to cool
further so that it can withstand the pressure of wrapping, and remain in stick form. The
whipped variety of margarine is processed by the injection of nitrogen into the emulsion
where it is either packaged as a tub or stick (http://alfa.ist.utl.pt).
Operational Concerns in Mayonnaise & Margarine Manufacturing
For mayonnaise and margarine production, the main concern is safety and
contamination. It is expected that the operator(s) should be following good manufacturing
practices (GMPs) and standard operating procedures (SOPs) when they make their
21
respective product. This means that personal protective equipment not limited to safety
boots, goggles, and lab coats need to be worn (McLaughlin Interview). Also, the
equipment must be cleaned and sterilized both before and after processing. It is expected
that auditing be performed within specified time periods to assure that such regulations
are being followed. This would include performing microbiological surface wipe on all
equipment (Fendinger Interview).
Conclusion
Margarine and mayonnaise are mixtures of fats, oils along with carbohydrates and
proteins and are useful energy sources of chemical energy in the diet. Oils provide
energy, fat-soluble vitamins and essentially fatty acid that are required for proper growth
and development. Cholesterol is required for homeostasis, because it is both an essential
component of cell membrane and an intermediate in the biosynthesis of steroid
hormones. The production of vegetable oil products is highly throughout the world and
consumption is increasing especially throughout the lower socioeconomic groups.
As one of the most mature markets in the grocery world, fats often struggles to
match other sectors in terms of innovation. The nature of margarine and mayonnaise is
there is only so much they will be consumed. As increasing consumption is not an option,
pricing strategies have played a big part in the shape of the market. Reducing production
cost is the key strategy. Understanding the product chemistry and colloid properties are
crucial to reduce production cost and meet the market demands.
For the last several years, the margarine category has been in decline, mainly due
to negative publicity and research studies about trans fats. However, National Association
of Margarine Manufacturers invested a large amount of funds on doing research. Results
of the study have shown margarine significantly lowered totally cholesterol and LDL.
Subsequent follow up advertising and media coverage was widespread, the sales
increased by an astonishing 10% in a matter of weeks. The total margarine/spread
category had sales of $1,292.8 million in year 2000.
Manufacturers have focus on the cost efficiency in mayonnaise production due to
the tough competition. Other than cost efficiency, consumer demand such as a perfect
texture, free-thaw stability and the ability to absorb water form. Last but not least, many
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of today consumers is looking for a cleaner label. Mayonnaise has a huge market in U.S.
according to supermarket business, 2000 sales of mayonnaise was $747.45 million
dollars.
Taking an average of the market price of mayonnaise, regular mayonnaise costs
around $0.88 per lb but only $0.34 cents to make (Fendinger Interview). On the other
hand, low-fat mayonnaise/ light mayonnaise is around $1.42 per lb. Regular margarine is
sold in the grocery store for $1.30 per lb. and low fat-cholesterol margarine is around
$2.00 per lb. Generally, low-fat product is more expensive than regular product due to the
cost of production.
“The next stage of food treads has been set and once again, flavor plays the
biggest role. Healthy eating has a significant though undefined parted. Audiences carve
novelty, but the food industry is also aware of the parameters: different but not too
different. It will always be in the mix.” (Restaurant and Institutions, January 1, 1999)
23
Sources
Aluko, R.E., KeeratiuraiM, Mine Y., Competitive adsorption between egg yolk lipoprotein and whey protein on oil-in-water interfaces, Colloids and surfaces B: Biointerfaces 10, 1998, 385-393. Campanella O. H, Peleg M, Analysis of the transient flow of mayonnaise in a coaxial viscometer, J. of Rheology, 31(6), 1987, 439-452.
Davis S., Rheological properties of semi-solid foodstuffs J. Text. Studies, 4, 1973,15-40.
Deis, Ronald. “Salad Dressing and Sauces: Through Thick and Thin.” Food Product Design. May 2001.
Depree,J.A. and Savage,G.P. “Physical and Flavour Stability of Mayonnaise.” Trends in Food Science and Technology. 12(2001)
Fisher, Harry J., and F. Leslie Hart. Modern Food Analysis. New York: Springer-Verlag, 1971.
Furia, Thomas E. HandBook of Food Additives. Cleveland: CRC, 1968.
J.M.H. Janssen, H.E.H. Meijer, A 2-Zone Model, Polymer Engng. & Sc., 35(22), 1995, 1766-1780.
Gallegos C., Berjano M., Linear viscoelastic behavior of commercial and model mayonnaise, Soc. Rheology, 36(3), 1992, 465-477.
Goshawk J A, Binding D M, Rheological phenomena occurring during the shearing flow of mayonnaise, J. Rheol, 42(6), 1998, 1537-1553.
Jacobs, Morris B. The Chemistry and Technology of Food and Food Products. Vol. 2. New York: Interscience, 1951.
Kiosseoglou,VD and Sherman, P. “Influence of Egg Yolk Lipoproteins on the Rheology and Stability of O/W Emulsions and Mayonnaise.” Colloid and Polymer Science. Volume 261, June 1983
Paraskevopoulou A, Kiosseoglou V, Alevisopoulos S, Kasapis S, Influence of reduced-cholesterol yolk on the viscoelastic behavior of concentrated O/W emulsions, Colloids and Surfaces B: Biointerface 12, 1999, 107-111.
Solomons, T.W. Graham. Organic Chemistry. 5th ed. New York: John Wiley & Sons, 1992.
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Stokes, R.J. and Evans, D.F. Fundamentals of Interfacial Engineering. Wiley VCH. 1997
Winton, Andrew L. The Structure and Composition of Foods. Vol. 3, New York: John Wiley & Sons, 1937.
Websites
http://alfa.ist.utl.pt/~fidel/creac/sec373.html
http://www.bestfoods.com/profile_history_bestfoods.shtml
www.bran-luebbe.co.uk/mayo.htm
http://www.foodproductdesign.com/archive/1995/1095DE.html
www.foodservicedirect.com
www.foodstarch.com
www.gowcb.com/products/systems/mayonnaise.htm
http://www.gowcb.com/products/systems/PDF/9825MARGARINETUBSTICKLINE.PDF
http://www.margarine.org/historyofmargarine.html
www.seps.org/oracle/oracle.archive/Physical_Science.Chemistry/2001.01/000978561267.7817.html
United States. Food and Drug Administration. Center for Devices and Radiological Health. Code of Federal Regulations Title 21- Food and Drugs. Sec 169.140 Mayonnaise. 1 April 2001. http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfPCD/ShowCFR.cfm?FR=169.140
United States. Food and Drug Administration. Center for Devices and Radiological Health. Code of Federal Regulations Title 21- Food and Drugs. Sec 166.110 Margarine. 1 April 2001. http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfPCD/ShowCFR.cfm?FR=166.110
www.xanthan-gum.net
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Personal Interviews
Fendinger, Andrew. Personal Interview. 13 Mar 2002.
Maiolino, Dana. Personal Interview. 1 Apr. 2002.
Mclaughlin, Barry Personal Interview. 13 Mar 2002.
Product Data Bulletins (PDB #)(Organized according to Product)
Mayonnaise
1. Karlshamns® USA Inc. (Columbus, Ohio): Soybean Oil2. Global Egg® Corp. (Etobicoke, Ontario): Whole Eggs3. Julius Goldman’s Egg City® (Moorpark California): Egg Yolks4. Indian Summer® (Lyndonville, New York): Vinegar5. IMC Salt® (Overland Park, Kansas): Sodium Chloride6. Colonial® Sugars, Inc. (Gramercy, LA): Sugar7. Sunkist® Growers, Inc. (Ontario, California): Lemon Juice
Reduced Fat Mayonnaise Additions
8. National Starch & Chemical Corporation® (Bridgewater, NJ): Modified Corn Starch9.Maple Lynn Foods® (Upton, QC): Egg Whites10. FMC® (Philadelphia, PA): Cellulose Gel11. Hercules® (Wilmington, DE): Cellulose Gum12. Nealanders® International Inc. (Etobicoke, Ontario): Xanthan Gum13. Gumix® International (Hackensack, NJ): Xanthan Gum14. Kalama® Chemical, Inc. (Need Location): Sodium Benzoate
Margarine
15. Central Soya® (Fort Wayne, Indiana): Partially Hydrogenated Soy Oil, Soy Lecithin16. Ault Performance® Ingredients (St. Laurance, QC): Whey17. Loders Croklaan® (Glen Effyn, Illinois): Mono-and Diglycerides18. Archer Daniels Midland® Co. (Decatur, Il): Lecithin19. American Hoechst® Corp. (Somerville, NJ): Potassium Sorbate20. Rhone-Poulene® Basic Chemicals Co. (Shelton, CT): Phosphoric Acid21. Roche® Vitamins Inc. (Parsippany, NJ): Beta Carotene, Vitamin A Palmitate
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