Caballero B. (ed.) Encyclopaedia of Food Science, Food Technology and Nutrition. Ten-Volume Set

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MARGARINE

Contents

Types and Properties

Methods of Manufacture

Composition and Analysis

Dietary Importance

Types and Properties

M Vaisey-Genser, The University of Manitoba,

Winnipeg, Manitoba, Canada

Background

0001 Margarine was invented in France by Hippolyte

ges-Mouries in response to Napoleon III’s call for

a cheap alternative to butter for French workers and

for his armies in the Franco-Prussian war. The first

margarine, consisting of beef tallow churned with

milk, was patented in 1869. Dutch entrepreneurs at

Jurgens & Co., an established butter trader, pur-

chased the margarine patent and popularized its use.

Margarine production was limited by the availability

of beef tallow until 1902 when Wilhelm Normann

in Germany patented a process to harden oils by

hydrogenation. This greatly expanded the market

opportunities for vegetable oils and the availability

of margarine. (See Vegetable Oils: Oil Production and

Processing.)

0002 By its centennial in 1969, margarine production

in parts of Europe and in the USA began to rival

that of butter. By 2000, margarine had become the

table spread of choice for many people for reasons of

either health or economics. Where this is the case, it

also serves as a versatile fat in the home and in the

food-service industry for preparing pan-fried foods,

sauces, and bakery goods. This review considers the

patterns of margarine consumption, the types of mar-

garine available at the beginning of the twenty-first

century, the physical structure of margarine, and its

functionality, that is, its physical and sensory proper-

ties and their stability.

Margarine Consumption Patterns

0003 The rate of margarine adoption has varied among

countries, reflecting the relative strength of consumer

groups and the oilseed industry in overcoming

restrictive legislation achieved by dairy lobbies.

Margarine was welcomed throughout Europe from

its earliest introduction. However, the reverse was

true in North America. In Canada, dairy farmers

succeeded in imposing, in 1886, a countrywide ban

on the manufacture, sale, and importation of margar-

ine. Its prohibition endured until 1948, when the

responsibility for margarine was transferred to each

province. However, a federal excise tax was imposed

on manufacturers until 1967. It took until the late

1990s for margarine to be sold legally in all 10 prov-

inces, and even then, several imposed a color restric-

tion on margarine to distinguish it from butter. In

1950, the USA abolished federal restrictive margarine

taxation opening the door for liberal marketing.

Nevertheless, some states resisted the legal sale of

margarine for several years.

0004Contrary to Napoleon III’s original expectation,

the tablespread competition between margarine and

butter has not centered solely on price. Some margar-

ines have the advantage of being easy to spread, even

at 4



C, fresh from the refrigerator. This performance

feature, coupled with a perceived nutritional advan-

tage for vegetable oil-based spreads, led to early

increases in margarine acceptance. In the USA, per-

capita consumption of margarine surpassed that of

butter in 1965 and more than doubled it 10 years

later, a dominance which has been sustained into the

last years of the twentieth century (Table 1). In both

Canada and the UK, the shift from butter to margar-

ine has been slower. Consumer research in Finland

reported equal use of the two spreads in 1992 for a

total of 15 kg per person per year. In France, butter

apparently continues to be dominant.

0005In North America, there has been a gradual de-

crease in total table spread consumption over the

last four decades of the twentieth century. In Canada,

for example, the sum of margarine plus butter disap-

pearance shown in Table 1 dropped from 13 kg per

capita in 1955 to less than 8 kg per capita in 1995. In

the USA, a decrease was also evident; total table

spread disappearance dropped from almost 8 kg per

capita in 1965 to only 5.8 kg per capita in 1995. Total

table spread use in the UK also moderated between

3704 MARGARINE/Types and Properties

1975 and 1985. Reductions in table spread consump-

tion appear to be a positive response to nutrition

educators’ emphasis on the importance of lowering

dietary fat to 35% of total energy intake to reduce

the risk of cardiovascular disease. Health-conscious

seniors and maturing baby boomers are paying atten-

tion, at least in their consumption of table spreads.

Market Form: Classification

0006 The worldwide standard for margarine has been set

by the Codex Alimentarius Commission for products

containing a minimum of 80% fat and a maximum

of 16% water (No. 32-1981, Rev.1-1989). It defines

margarine as a ‘food in the form of a plastic or fluid

emulsion, which is mainly composed of the type

water/oil, produced principally from edible fats and

oils, which are not mainly derived from milk.’

The standard lists permitted additives, which include

vitamins, flavorings, colorants, emulsifiers, and

preservatives.

By Firmness

0007 Margarine table spreads are marketed in forms

which are broadly classed as either hard or soft. The

distinguishing feature is the degree of fluidity at the

time of packing. Hard margarines are firm enough to

be molded into a stick, print, or brick form. Soft

margarines, which contain more oil than hardened

fat, are too fluid to hold their shape and so require

packaging in plastic or coated paperboard tubs. Stick-

type margarines vary widely in their degree of hard-

ness as the liquid oil in the formulation may range

from as low as 5–10% to an upper limit of 60–65%.

In contrast, the liquid oil in soft products may range

from 60–65% to 80–85%. To enhance the spread-

ability, either type may be whipped with nitrogen or

air, usually to a 33% volume increase. Liquid margar-

ine was introduced in Europe and the USA in the

1960s. Its use continues to be modest.

0008In 1980, stick forms accounted for about two-

thirds of the nondairy table spread market in the

USA and continue to be popular. However, in

Canada, where brick margarines have typically been

firmer than those in the USA, the soft tub types had

captured about 75% of market sales by 1995. With

continuing emphasis on decreasing the intake of fat,

particularly saturated fat, it is likely that soft margar-

ines, which ‘go farther’ on spreading, and their low-

fat counterparts will continue to retain a substantial

proportion of the consumer market for table spreads

in developed nations.

By Fat Combinations

0009Blends of margarine with butter, known in some areas

as butterines, are popular in a number of countries

within the EC and Scandinavia. For example, Sweden

introduced the butter spread Bregott in 1969. The

acceptance of this product, in which 20% of the

milk fat was replaced with liquid oil, was credited

with successfully reversing a decline in Swedish dairy

sales. However, in some parts of the world, butter–

margarine blends are still viewed as adulteration of

dairy products. In Canada, for example, by 1999,

blends were permitted in only five of 10 provinces,

where either 50:50 or 20:80 blends of butter to mar-

garine, respectively, could be marketed. Limiting the

replacement of butter by margarine to only 20%, as

in Sweden’s Bregott may be the better choice as far as

flavor is concerned. Sensory tests carried out in 1982

and summarized in Table 2 showed that both margar-

ine and a blend of 80% margarine with 20% butter

had significantly less buttery flavor than the butter

prototype. However ‘half-and-half’ mixtures could

be mistaken for either margarine or butter.

By Fat Content

0010‘Reduced fat’ margarines are those with less than

80% fat. They have been introduced in several parts

tbl0001 Table 1 Examples of changes over time in margarine and

butter consumption (kilograms per capita per annum, retail

weight)

Ye a r U SA

Canada

Margarine Butter Margarine Butter Margarine Butter

1955 3.67 9.34 8.57

1965 4.75 3.12 3.95 8.44

1975 5.01 2.14 5.18 5.18 7.10 8.92

1985 4.89 2.21 6.33 3.99 6.60 4.64

1995 4.17 2.04 5.17 2.76

1997 3.90 1.99 4.11 2.62

Adjusted from Oil Crops Situation and OutlookYearbook, 1966^1998.US

Department of Agriculture, Economic Research Service.

Adapted from Food Consumption in Canada Part II, 32-230-XB, Annual,

Appendix A, p. 46. Statistics Canada 1998.

Adapted from Agricultural Outlook. Paris: Organization for Economic

Cooperation and Development. Aggregation of these data was

subsequently discontinued.

tbl0002Table 2 Buttery flavor in margarine, butter, and blends

Table spread(brick form) Meanrelativeintensity

of buttery flavor

b,c

Butter 1.21

Blend, 50 butter:50 margarine 0.80

Blend, 20 butter:80 margarine 0.29

Margarine 1.00

Adapted from Fyfe B and Vaisey-Genser M (1983) Salty and buttery

flavors from tablespreads. Canadian Institute of Food Science and

Te c h n o l o g y J o u rnal 16: 206–211.

Mean score of 18 judgments/spread (six judges  three pairs).

c,d,e

Values with the same letter are not significantly different (P < 0.05).

MARGARINE/Types and Properties 3705

of North America and Europe, with the goal of

decreasing consumers’ total fat intake to lower the

risk of heart disease. The amount of fat reduction

varies. Where the fat content is approximately half

of the prototype, i.e., *40%, the spread may be

referred to as minarine, halvarine, calorie-reduced

(Canada), ‘lite’ or light margarine (USA), Mini-Light

(Poland).

Structure

0011 Margarine is a water-in-oil emulsion, in which the oil

phase consists of both liquid oil and crystalline fat

at room temperature. The semisolid structure is

achieved by a three-dimensional, continuous, sheet-

like matrix of fat crystals or crystal aggregates which

entraps tiny water droplets suspended in oil. Struc-

tural integrity is due to irreversible primary chemical

bonds and to reversible secondary bonds formed

through weak London–van der Waals forces. (See

Colloids and Emulsions.)

0012 The number and size of the fat crystals in a margar-

ine vary with the chemical composition of the oil

source(s) and with its processing. Formulations are

controlled to encourage the formation of many small

crystals, which are each about 1 mminlength,andto

prevent their polymorphic transition, that is, a shift to

fewer but larger and more stable b crystals, which are

20–30 mm in length. At a high solids content, a network

of b crystals will result in a brittle, hard margarine,

while at a low solids content, the large crystals are less

able to form a continuous matrix, and the product may

become oily. Ideally, the solid crystal particles are so

small that the force of gravity is exceeded by the adhe-

sion of the particles, and the spaces between them are

small enough to preclude the seepage of the liquid

phase. Such a structure confers upon margarine the

desirable property of plasticity.

0013 Scanning electron microscopy has shown that the

water droplets in a margarine emulsion may be

as small as 1 mm in diameter, so that there may be as

many as 5–10  10

per milliliter. Emulsifiers such as

monoacylglycerols, diacylglycerols, lecithin, and milk

proteins are located at the water–oil interface. They

assist in dispersing the water as droplets in the oil

during the formation of the emulsion and in keeping

it dispersed due to their dual, but unbalanced, affinity

for both phases. A dominance of nonpolar groups on

the emulsifier succeeds in lowering the interfacial

tension among oil molecules more than is effected

by its polar groups on water, so that oil becomes the

continuous phase. The presence of both lipophilic

and hydrophilic groups in the emulsifier at the

water/oil interface is necessary for emulsion stability.

(See Emulsifiers: Organic Emulsifiers.)

Physical and Sensory Properties

Appearance

0014Color and gloss are the main determinants of margar-

ine appearance. Both properties may be monitored

by instruments such as the Hunter colorimeter or

the Lovibond tintometer. b-Carotene, annatto, and

tumeric are additives permitted in Canada to match

the color intensity and hue of margarine to that

of butter, a practice which was often banned in

earlier years. In fact, punitive color requirements

were imposed on margarine in several Canadian

provinces for many years and in one, Ontario, until

1995.

0015Gloss or sheen, as opposed to a dull, matte surface,

is a function of light reflectance from subsurface

layers of oil droplets, which is influenced by the tight-

ness of the emulsion. Excessive glossiness develops if

the fat crystal network is not sufficiently fine or firm

to enmesh the liquid oil. Soft margarines tend to be

glossier than the hard type, due to the higher content

of liquid oil. In the same context, Finnish scientists

have reported that sensory panels perceived signifi-

cantly less glossiness in reduced fat spreads than in

those spreads with normal fat levels. (See Sensory

Evaluation: Sensory Characteristics of Human

Foods; Appearance.)

Texture

0016Spreadability and rate of mouth melt are two textural

properties of table spreads which depend upon the

relative amount of solid fat present and its crystalline

structure. While both textural characteristics reflect a

collective response to temperature and work, their

criteria for success are somewhat in opposition.

Good spreadability requires that the product retain

its plasticity, as it is molded with modest pressure over

temperatures ranging from refrigerator to room

(4–22



C). Desirable mouth melt, however, requires

rapid melting at mouth temperature (35–37



C) for

prompt flavor release and clearance.

0017The traditional quality control tool for estimating

spreadability has been the solid fat index (SFI) using

dilatometry to measure volume changes as solid mar-

garine converts to liquid when equilibrated at three

temperatures: 10, 21, and 33.5



C. Figure 1 illustrates

the SFIs for butter and three different margarines.

Sensory testing has shown that SFI values between

10 and 20, at the temperature of use, predict good

spreadability, while values of 35 and 7 are, respect-

ively, too hard or too soft/oily to spread. Of the SFI

curves in Figure 1, the flatter patterns for the soft stick

and soft tub margarines illustrate desirable spread-

ability, even at a temperature of 10



C, whereas butter

3706 MARGARINE/Types and Properties

is not spreadable until it reaches 20



C. More recently,

nuclear magnetic resonance (NMR), which depends

on differences in the magnetic environment of

protons in the solid and liquid phases, is being used

to assess the spreadability of table fats. The solid fat

content (SFC) values from NMR evaluations are con-

sidered more reliable than SFIs, particularly for

samples at high solids content at lower temperatures.

(See Sensory Evaluation: Texture; Spectroscopy:

Nuclear Magnetic Resonance.)

0018 Rapid mouth melt of table spreads provides a

cooling sensation due to absorption of the heat of

crystallization in melting and is accompanied by

prompt flavor release. Figure 1 shows that butter

has a steeper SFI slope and therefore more rapid

mouth melt than any of the margarines. This provides

it with an advantage which is difficult for the proces-

sor to duplicate without sacrificing spreadability.

Sensory panel measurements of mouth melt time for

1 ml samples of Canadian table spreads on the 1982

market confirmed that butter melted significantly

faster than brick margarines whether the starting

temperature was 4



C (18 s vs. 22 s, respectively) or



C (11 s vs. 16 s, respectively). To our knowledge,

the extent of the differences in mouth cooling sensa-

tions among table spreads as they melt has yet to be

documented.

Flavor

0019Although North Americans have used as much or

more margarine than butter since the mid-1970s, a

1986 survey of 4000 US consumers by the dairy in-

dustry found that the majority still preferred butter.

Europeans echo the same sentiment, even though

North Americans usually use salted and sweet cream

table spreads, while Europeans favor cultured butter

and unsalted spreads. For example, sensory studies in

Poland and Finland reported in 1989 that margarines

often lacked buttery flavor. In the absence of reports

to the contrary, flavor apparently remains a challenge

for the margarine processor.

0020Margarine flavor is a combined response to odor-

ants soluble in the fat phase and tastants dissolved in

the water droplets. Permitted flavor additives include

compounds which have been identified as important

in butter aroma such as diacetyl (1–4 p.p.m.),

dimethyl sulfide, lactones, ethyl esters of short-chain

fatty acids, ketones, and aldehydes. When ordinary

salt is added to table spreads, it is the main tastant,

although the lactose from milk solids will add a

modest amount of sweetness. In a number of spreads,

salt levels have been reduced from 2.0–3.0% by

weight to 1.0–1.5%, in the interests of lowering the

intake of dietary sodium. Sensory tests on a range of

salt concentrations in butter have shown that reduc-

tions of this order of magnitude have little effect on

perceived saltiness intensity. Sensory tests comparing

the perception of salt in water and in butter show in

Figure 2 that the high fat content of a water-in-oil

Butter

Stick margarine

Soft stick margarine

Soft tub margarine

Solid fat indices

Temperature (8C)

20 30 40

fig0001 Figure 1 Effect of temperature on table spread percentage

solids. Drawn from data cited by Chrysam M (1985) Table spreads

and shortenings. In: Applewhite TH (ed.) Bailey’s Industrial Oil and

Fat Products, vol. 3, pp. 41–127. New York: John Wiley.

0.0

0.10

1.00

10.00

Salt in water s = 6.46C

1.16

Salt in butter s = 0.63C

1.27

0.10

Salt concentration (%)

RIl

Magnitude estimate

1.00 10.00

fig0002Figure 2 Psychophysical relationships of salty intensity with

salt concentration in water and in butter; Rl, Rll, C, S, and Sf are

various retail margarines, and B is butter. From Vaisey-Genser M

and Vane BK (1995) Sensory evaluation of margarine. In:

Warner K and Eskin NAM (eds) Methods to Assess Quality and

Stability of Oils and Fat-containing Foods, pp. 76–106. Champaign,

IL: AOCS Press, with permission. Originally published as Fyfe B

and Vaisey-Genser M (1983) Salty and battery flavours from

tablespreads. Canadian Institute of Food Science and Technology

Journal 16: 206–211.

MARGARINE/Types and Properties 3707

emulsion like a table spread interferes with the per-

ception of a water-soluble tastant like salt as much as

10-fold. However, altering the salt content may affect

the overall flavor balance of margarine because of

influences on the partition coefficients of volatile

components. (See Sensory Evaluation: Taste.)

0021 The flavor advantage of rapid mouth melt has been

demonstrated with simulated margarines consisting

of 0.01% diacetyl and other dairy flavors combined

with liquid soybean oil melted with either palm

stearin or palm olein and recrystallized at 0



Figure 3 shows the flavor intensity patterns described

by trained panelists in time-intensity studies of 2.5-ml

samples of these two products. Total flavor intensity

peaked after 12 s in the mouth in both products, but

flavor was consistently more intense in the more

rapidly melting palm olein product. These sensory

findings were confirmed by mass-spectrophotometric

headspace measurement of diacetyl using the same

simulated margarine products agitated at 35



C with

glass beads and artificial saliva.

Stability

0022 Standard 80% fat margarine normally has a shelf

life of 6–12 months if the product is refrigerated

during marketing, distribution, and home storage.

This period is shorter for low-fat, high-moisture

products and for those which are salt-free.

Microbiological spoilage

0023The growth of molds and yeasts is limited by control-

ling the water droplet size and by the addition of salt

and other preservatives. Where droplets are smaller

than 10 mm and the amount of milk solids is limited, it

can be calculated that, per water droplet, there is not

enough nutrient to sustain microbial growth. Accord-

ingly, emulsion stability fosters keeping quality. Salt

levels of 1.0–1.5% in margarine are considered neces-

sary to avoid microbial hazard. At the level of 1.0%

by formula weight, there would be a salt concentra-

tion of 6.25% in the serum, assuming 16% water in

the margarine formula. Preservatives such as sorbic

acid and benzoic acid or their respective sodium or

calcium salts add protection by lowering the pH. A

pH of 5–6 is recommended for salted margarine and a

more acidic pH of 4–5 for unsalted products. (See

Preservation of Food; Spoilage: Bacterial Spoilage.)

Graininess

0024Margarines prone to poymorphism may exhibit tex-

tural instability during storage at refrigerator tem-

perature (4



C), which is perceived as graininess and

is due to crystal growth. This phenomenon is exagger-

ated by fluctuating storage temperatures. In Figure 4,

sensory estimates of the presence or absence of graini-

ness in a margarine during 6 months’ refrigerated

storage have been plotted against measurements of

crystal size from photographs taken under polarized

light. These data show a sensory detection threshold

of crystal size as 22 mm. It remains likely that the

sensation of graininess is a function of both the size

Total flavor intensity

4 8 12 16 20 24 28

Time (sec)

32 36 40 44 48

fig0003 Figure 3 Effect of margarine melting point on the time and

intensity of sensory flavor release; — palm olein; --- palm stearin;

0, none; 5, moderate; 10, a great deal. From Lee WE (1986) A

suggested instrumental technique for studying dynamic flavor

release from food products. Journal of Food Science 31: 249–250,

with permission.

0.02

Average crystal size (Microns)

Graininess detection (%)

10 20 50

fig0004Figure 4 Relationship between fat crystal size in margarine

and the percentage of panelists detecting graininess. Adapted

from Vaisey-Genser M, Vane BK and Johnson S (1989) Graini-

ness, Crystal size and firmness of stored canola margarines.

Journal of Texture Studies 20: 347–361.

3708 MARGARINE/Types and Properties

and the number of crystals. In cases of exaggerated

crystal growth, there is the hazard of increased sus-

ceptibility to microbial spoilage. The development of

extremely coarse fat crystals may squeeze liquid oil

from the product and allow partial coalescence of

the aqueous phase. Free moisture on the surface

may result in mold growth. (See Spoilage: Molds in

Spoilage.)

Flavor

0025 The stability of margarine flavor is enhanced by re-

frigerated storage to retard autoxidation of the oil

and by lightproof packaging to avoid photooxida-

tion. Changes by either mechanism produce off-

flavors in oils which are variously described as

beany, painty, or fishy. The trend to greater use of

soft margarines with higher proportions of liquid oil

increases the risk of autoxidation, particularly when

the oils used are high in unsaturated fatty acids. The

addition of antioxidants is permitted to reduce this

hazard. Photochemical oxidation of liquid oils has

been shown to be greater at short wavelengths, with

a maximum below 455 nm. As fluorescent light in

supermarkets may transmit wavelengths between

350 and 750 nm, packaging impervious to low-wave-

length light is highly recommended for maximum

margarine flavor protection. (See Antioxidants:

Natural Antioxidants, Synthetic Antioxidants.)

See also: Antioxidants: Natural Antioxidants; Synthetic

Antioxidants; Colloids and Emulsions; Emulsifiers:

Organic Emulsifiers; Preservation of Food; Sensory

Evaluation: Sensory Characteristics of Human Foods;

Appearance; Texture; Taste; Spectroscopy: Nuclear

Magnetic Resonance; Spoilage: Bacterial Spoilage;

Molds in Spoilage; Vegetable Oils: Oil Production and

Processing

Further Reading

Chrysam M (1985) Table spreads and shortenings. In:

Applewhite TH (ed.) Bailey’s Industrial Oil and Fat

Products, vol. 3, pp. 41–127. New York: John Wiley.

deMan JM, Dobbs JE and Sherman P (1979) In: Sherman P

(ed.) Food Texture and Rheology, pp. 43–54. London:

Academic Press.

Heick WH (1991) A Propensity to Protect: Butter, Margar-

ine and the Rise of Urban Culture in Canada, pp. 1–163.

Waterloo, Canada: Wilfred Laurier Press.

Hellemann U, Tuorila H, Lampi A-M and Matuszewska I

(1990) Hedonic responses and attitudes related to fats

used as spreads on bread. Food Quality and Preference

2: 29–38.

Juriaanse AC and Heertje I (1988) Microstructure of short-

enings, margarine and butter – a review. Food Micro-

structure 7: 181–188.

Lee WE (1986) A suggested instrumental technique for

studying dynamic flavor release from food products.

Journal of Food Science 31: 249–250.

Mela DJ and Marshall RJ (1992) Sensory properties and

perceptions of fats. In: Mela DJ (ed.) Dietary Fats: De-

terminants of Preference, Selection and Consumption,

pp. 43–47. London: Elsevier.

Rohm H and Raaber S (1991) Hedonic spreadability

optima of selected edible fats. Journal of Sensory Studies

6: 81–88.

Vaisey-Genser M, Vane BK and Johnson S (1989) Graini-

ness, crystal size and firmness of stored canola margar-

ines. Journal of Texture Studies 20: 347–361.

Vaisey-Genser M and Vane BK (1995) Sensory evaluation

of margarine. In: Warner K and Eskin NAM (eds)

Methods to Assess Quality and Stability of Oils and

Fat-containing Foods, pp. 76–106. Champaign, IL:

AOCS Press.

van Alphen J (1969) Hippolyte Me

ge-Mouries. In: van

Stuyvenberg JH (ed.) Margarine – An Economic, Social

and Scientific History 1869–1969, pp. 6–8. Liverpool,

UK: Liverpool University Press.

Methods of Manufacture

R A Carr, Carr & Associates, Burlington, Ontario,

Canada

M Vaisey-Genser, The University of Manitoba,

Manitoba, Winnipeg, Canada

This article is reproduced from Encyclopaedia of Food Science,

Background

0001Consumers have grown to appreciate the margarine

products that spread easily at refrigerator tempera-

tures and are enjoyed because of their flavor and

texture. To understand the dynamics of the manufac-

ture of these margarines, it is essential to appreciate

the relationships between the processing effects, the

specific physical properties of the products, and the

composition of their oil blends and other compon-

ents. A major factor in the formulation and control of

margarine oils and margarine is the development of

desirable solids-to-liquid ratios, achieved by hydro-

genation and blending. The types of oils selected for

margarine oil formulations are also important in

obtaining a stable, uniform crystal structure from

specific conditions for processing the oils, as well as

the finished margarine products. As a result, margar-

ines as semisolid plastic products in soft tub and

wrapped stick forms have been designed to meet con-

sumer demands for health and dietary benefits, as

well as performance and convenience.

MARGARINE/Methods of Manufacture 3709

Physical Properties

0002 A margarine structure is a network of small fat crys-

tals, which acts as a matrix to contain trapped oil

and water globules. The degree of finished product

spreadability depends considerably upon the propor-

tion and properties of the liquid oil and crystalline fat

in the margarine oil component. Butter and stick

margarines, for example, are brittle when cold from

the refrigerator. They gradually become more spread-

able as they approach room temperature, because

some of the fat crystals melt as the margarine becomes

warmer. Consumers desiring spreadability from the

refrigerator may select soft tub margarines, which are

designed with lower solids and higher liquid oil con-

tents. Various combinations of hydrogenation, frac-

tionation, interesterification, and blending of diverse

oil types and solids contents allow the development of

margarines with differing consistencies and proper-

ties. (See Colloids and Emulsions.)

0003 Margarine consumers fall into two main classifica-

tions, each with specific quality requirements. The

domestic cook requires a product for table use as

well as baking and frying. The professional baker

demands products that will give a consistent perform-

ance for cakes, icings, etc. For the home, a margarine

must provide an enjoyable flavor that releases fully

and quickly, must melt rapidly in the mouth leaving

no gummy or gritty sensation, have sufficient body at

room temperature to maintain its form, and must be

easy to spread over a broad range of temperatures.

Creamability, which is the ability to take up air when

beaten, and plasticity are the key priorities required

for satisfactory baking. For frying, the fat component

must remain stable at high temperatures and contain

virtually no free fatty acids, which create a smoking

problem during drying.

0004 The physical properties of various margarines

depend primarily upon (1) the melting point of the

oil component triglycerides, (2) the total solids con-

tent present at any given temperature, (3) the distri-

bution of these solid fats over a broad temperature

range, and (4) the polymorphic modification of

crystal habit of the fat composition. Their combined

response to temperature and work applied by exter-

nal forces is the most characteristic. Margarine is

designed to meet flavor, plasticity, and creamability

requirements by combining a properly designed mar-

garine basestock with an aqueous phase blend so that

the water globules are finely dispersed, but combined

loosely enough for the emulsion to break easily upon

melting. The aqueous phase generally consists of re-

constituted milk powder, brine, and water. Vitamins,

coloring, and flavoring agents are included, and

emulsifiers, such as monoglycerides and lecithin, are

added to the oil phase. (See Triglycerides: Structures

and Properties.)

Formulation

0005To ensure the development of a proper margarine

emulsion prior to the crystallization process, two

distinct phases, aqueous and oil, must be prepared

individually, prior to blending (Figure 1). The com-

position of the phases is designed for the three basic

types of margarines: (1) stick or regular margarine,

(2) soft or tub margarine, and (3) diet or calorie-

reduced margarine.

0006Diet margarines contain half as much margarine oil

as the stick or tub margarines. Because of their higher

water content, they are unsatisfactory for cooking

purposes, but are used for spreading on bread by

consumers interested in their lower energy content.

Aqueous Phase

0007The major component in the margarine aqueous

phase is either sweet skim milk or water plus reconsti-

tuted skim milk powder, or even water without milk if

required. Care is taken that the milk is properly pas-

teurized by rapid heating to 75



C with sufficient

contact time. If desired, cultured milk, which has

had some of the lactose content converted to lactic

acid, may be used to provide a distinct flavor and

acidity to the milk.

0008Salt, or brine, is then added to the aqueous phase to

accentuate the flavor, act as a microbial inhibitor, and

reduce splattering during pan frying. Minor compon-

ents in the aqueous phase include citric acid, ethylene-

diaminetetraacetic acid (EDTA) and a water-soluble

dairy flavor. Citric acid reduces the pH of the liquid

phase to approximately 5.3, to enhance the perform-

ance of the microbial inhibitor. EDTA acts as a che-

lating agent by tying up any metal ions picked up

either in the equipment or from other components

added to the aqueous phase. (See Acids: Natural

Acids and Acidulants.)

Oil Phase

0009The main component in the oil phase is a margarine

oil basestock specifically developed through the refin-

ing process to produce a final margarine with the

appropriate flavor, keeping quality and melting char-

acteristics necessary to produce a specific margarine

with distinctive characteristics demanded by the con-

sumer. Oil basestocks originate from crude oils such

as soyabean, palm, corn, cottonseed, sunflower,

canola, and rapeseed. Initial processing through re-

fining and bleaching operations removes impurities

from the oil. Refined–bleached oils can be modified

3710 MARGARINE/Methods of Manufacture

by a hydrogenation process to alter their physical

properties, such as melting characteristics and stabil-

ity. Additional changes in the physical properties can

be obtained by blending different oils and interester-

ification. (See Ground Nut Oil; Palm Oil; Vegetable

Oils: Oil Production and Processing.)

0010 Changes to the physical properties, or hardness, of

a fat can be measured by melting points, dilatometry,

and nuclear magnetic resonance (NMR). Dilatometry

is based on the difference in specific volume for liquid

and solid fats at a specific temperature. Dilatometric

curves may be plotted for solid fat indices (SFIs)

against the temperature of determination. NMR pro-

vides a different approach to the determination of

solids in fats and their blends. The results are deter-

mined in absolute solids terms and are utilized to

provide a relatively simple technique for determining

SFI curves, which are somewhat comparable with

the dilatometric method. (See Spectroscopy: Nuclear

Magnetic Resonance.)

0011 Most vegetable oils are mainly liquid at room

temperature. Therefore, hydrogenation plays a key

role in the preparation of basestocks with various

SFI melting curves that can be blended for the prepar-

ation of margarine basestocks. Other techniques such

as fractionation, interesterification, directed interes-

terification, and corandomization, are also available,

but are normally used for specific situations related to

oil availability and for products requiring a distinct-

ive melting property, such as bakery margarines.

0012Liquid unsaturated oils have a relatively high

number of double bonds, melt at low temperatures,

are more unstable, and are likely to deteriorate over

time in terms of odor and flavor. Treatment of the oil

in hydrogenation convertors with a nickel catalyst at

high temperature with violent agitation, in contact

with a flow of tiny hydrogen bubbles, will insert

hydrogen into some of the double bonds. Approxi-

mately 0.01% catalyst and 200



C temperature are

required for margarine oil basestocks. As the process

proceeds, the melting point characteristics of the oil

are increased. They are measured by a refractometer

in the plant and confirmed precisely in the laboratory

by dilatometric or NMR analyses. When the proper

Culture tanks

Milk, salt

Emulsifying

agent

Blending and

weighing

Oil

storage

Oil and

oil-soluble ingredients

Blending and

weighing

Emulsion

mix tank

Votator

supply tank

Votator

A unit

Votator

B unit

Votator

print molder

Pump

To loading

platform

Wrapping and

cartoning

fig0001 Figure 1 Simplified flow diagram for continuous margarine solidification. Courtesy of the Girdler Co. Reproduced from Margarine:

Methods of Manufacture, Encyclopaedia of Food Science, Food Technology and Nutrition, Macrae R, Robinson RK and Sadler MJ (eds),

1993, Academic Press, with permission.

MARGARINE/Methods of Manufacture 3711

end points are obtained, the oil in the convertor is

cooled and then carefully filtered to remove all traces

of catalyst.

0013 Hydrogenation is the most flexible single process

for producing margarine basestocks. Depending upon

the operating conditions selected, the SFI curve can be

steepened or flattened by adjustment of hydrogen-

ation temperature, pressure, agitation, catalyst type,

and catalyst concentration. For example, selective

hydrogenation conditions using a high temperature

and lower pressure are utilized to promote high trans

fatty acid development with a minimum drop in

iodine value, to produce steep solids curves. Recently,

some nutritionists have expressed concern over the

effect of trans fatty acids on health. If ultimately

confirmed. Other techniques, such as enzymatic reac-

tions, can be utilized to provide basestocks with steep

melting curves and low trans fatty acid content.

0014 Differing from shortenings, margarine oil blends

are formulated to have a sufficient solids content at

room temperature to perform as a stick margarine or

tub margarine on the table, without slumping. At

refrigerator temperature, the solid content should be

kept at a minimum to ensure smooth, easy spread-

ability on bread when used directly from the refriger-

ator. In addition, margarines should melt very rapidly

at body temperature (37



C) to ensure a ‘quick get

away’ in the mouth with minimum gumminess. This

rapid melting characteristic is attained from the de-

velopment of trans fatty acids during hydrogenation,

which start to melt rapidly as the temperature is

increased above about 25



C. Opposite to the sharp

melting curve required for a margarine, shortenings

are formulated to produce flat melting curves, with

very little change in solid content, from room tem-

perature to temperatures well above body tempera-

ture. (See Fatty Acids: Properties.)

0015 In addition to the solids content curve, a second

important factor in margarine oil blends is their palm-

itic acid content (C

16:0

), which has a definite effect on

the crystal stability of the final margarine. Oil blends

with insufficient palmitic acid content tend to revert

from the b

crystal state to an undesirable b crystal

state during storage of the packaged product. b

crys-

tals produce both margarines and shortenings with a

smooth uniform texture, because of the small size of

the crystals, from 1 to 3 mm. However, b crystals are

larger than 20 mm in size and produce obvious grainy

texture and brittleness in margarines and shortenings.

b crystal margarines are readily detected by the

tongue as an undesirable gritty feel. Oils/fats that

are b-tending include canola, cocoa butter, coconut,

corn, lard, olive, palm kernel, peanut, safflower,

sesame, soya bean and sunflower. b

Types are cotton

seed, herring, milk fat, modified lard, palm and

tallow. It is normal practice to blend approximately

5–15% of cotton seed or palm oil in margarine oil

blends to minimize all possibilities of crystal conver-

sion to the b form. Some margarine manufacturers

use a larger number of different hardstock fractions

also to minimize the possibilities of b crystal develop-

ment. A crystal inhibitor such as sorbitan tristearate

can add crystal stability insurance more effectively

than diglycerides.

0016Final margarine oil blends are carefully formulated

to produce the desired solids melting curve. For

example, stick margarine solids contents are approxi-

mately 27% at 10



C, 14.2% at 21.1



C, and 2.5% at

33.3



C. Soft or tub margarines, with improved

spreadability characteristics, are approximately 13%

(SFI) at 10



C, 7% at 21.1



C, and 2.3% at 33.3



The stick margarine SFI profile provides sufficient

solids at 10



C to allow satisfactory parchment over-

wrapping during packaging, satisfactory spread-

ability at both room temperature and out of the

refrigerator, plus a good ‘get away’ in the mouth.

The margarine oil blend is then deodorized at about

250



C under a vacuum of 6 mmHg for 40 min to

remove flavor and odor components, prior to its use

in the margarine oil phase.

0017The oil phase is made up separately from the aque-

ous phase. Sufficient oil is pumped into the blend tank

to ensure that the final product will have an oil con-

tent of 80% in the final stick or tub margarine, or

40% for low-energy diet spreads. Approximately

0.2% lecithin is metered into the oil as an emulsifier

and antispattering agent during pan frying. Food

coloring and oil-soluble butter flavor (0.05% of

each) are added, and vitamins A and D are included

for nutritional purposes. Margarine flavor release can

be affected by the ‘tightness’ of the final oil/aqueous

emulsion. Tight emulsions reduce the flavor impact

as compared with loose emulsions. Therefore, phase

blending and crystallization practices need to be care-

fully controlled to ensure uniform flavor release

characteristics. (See Cholecalciferol: Properties and

Determination; Colorants (Colourants): Properties

and Determination of Natural Pigments; Properties

and Determinants of Synthetic Pigments; Emulsifiers:

Organic Emulsifiers; Uses in Processed Foods; Ret-

inol: Properties and Determination.)

Crystallization

0018Immediately prior to the packaging of margarine, the

liquid and oil phases are mixed together in a 1:4 ratio,

with gentle agitation, and maintained at about 40



The temperature is selected to develop a stable

emulsion and to prevent any precrystallization,

which would occur at temperatures below 37



C. A

3712 MARGARINE/Methods of Manufacture

proper emulsion will have the water phase droplets

finely dispersed in the oil phase, but loosely enough

for the emulsion to break easily on melting.

0019 Margarine emulsions can be made by either a batch

or continuous system. The batch system has been

used for many years and comprises an agitated, tem-

perature-controlled mixing tank to receive the water

and oil phases. After the batch has been mixed to

form a stable emulsion at the required temperature,

the emulsion is then pumped to a scraped-surface heat

exchanger for supercooling. The batch system is

usually used for operations required to produce

many different types of margarines with production

runs of relatively short duration.

0020 In lieu of a mixing tank, the continuous system may

use a three-headed proportioning pump to meter and

mix the oil phase continuously and the water phase

simultaneously in the proper proportions into an agi-

tated, temperature-controlled holding tank and then

directly to the scraped-surface heat exchanger. The

continuous system is designed for plants that run

large quantities of similar types of margarines over

extended time periods.

0021 A scraped-surface heat exchanger is a unit that

adds heat or removes heat from a substance. In the

margarine industry, it is used as a closed chilling

machine that induces partial crystallization of the fat

in the margarine emulsion, all taking place in stainless

steel, externally refrigerated cylinders through which

the fat is pumped continuously. The cylinders are

equipped with fast-revolving scraper blades that

work the fat to achieve efficient, even heat transfer

to the total mass in the heat exchange tubes. The

process, if desired, can be utilized to add air or gas

to a margarine, for the production of whipped mar-

garines. In the industry, the process is often called

‘votation,’ because the original units were produced

by the Votator Division of the Chemetron Corpor-

ation, Louisville, Kentucky.

0022 The objective of votation is to develop and seed b

crystals throughout the margarine, to ensure their

progression to the dominant crystal form in the fin-

ished product. If successful, the margarine will then

have a smooth textural feel on the tongue, as well as

contributing to a smooth-spreading performance on

bread. For long-term uniform production, attention

must be paid to the sharpness of votator blades and

the smooth condition of the chilling cylinders. For

margarine, the votator should rapidly reduce the in-

coming emulsion temperature from about 40 to 7



The votator, also called an ‘A unit,’ is designed for

direct-expansion refrigerants such as ammonia,

freon, and propane. Advantage is taken of its high

rate of heat transfer due to ‘surface boiling.’ A con-

siderable proportion of the liquid vaporizes upon

contact with the heat-transfer tube, and the velocity

of the gas carries a relatively high percentage of liquid

ammonia back to the surge drop, thus assuring com-

plete flooding of the heat-transfer surface at all times.

As a result, a constant uniform chilling effect is

achieved for margarine passing through the chilling

cylinder.

0023The emulsion is worked through the chilling cylin-

der over a period of about 18 s. Supercooled product

leaving the A unit is then pumped to the ‘B unit’

cylinder, which is considerably smaller in diameter

and longer than the B unit used for shortenings. In

addition, the margarine B unit is not agitated, so that

solidification of the supercooled margarine emulsion

takes place under almost static conditions. If desired

for whipped margarine, air or preferably an inert gas

such as nitrogen can be drawn into the emulsion at the

suction side of the product pump in precise amounts

regulated by flow meters as it is fed to the chilling

unit.

0024Limiting the amount of work given to the product

in the B unit (1) produces a product that is not too soft

to be handled in automatic print forming and wrap-

ping equipment, (2) prevents the aqueous phase from

being dispersed in a too fine state of suspension, and

(3) induces the growth of b

seed crystals from the

supercooled mass. Agitation in the B unit would re-

quire a long ‘dwell period’ for the product to become

firm enough for packaging. In addition, the resultant

tight emulsion and incorrect crystal structure would

delay melting of the product in the mouth, producing

a waxy impression with the user. Tight emulsions also

fail to yield the desirable milk and salt flavors before

the product has been swallowed, and contribute to

brittleness or hardness, which is reflected in the lack

of spreadability at refrigerator temperatures. While

the product is in the B unit, the temperature rises by

approximately 5



C, primarily due to the latent heat

of crystallization. The supercooled mass solidifies as

it is slowly forced through the B unit by the pressure

of the feed pump.

0025After leaving the B unit, the finished stick margar-

ine product is extruded in a rectangular form, shaped,

and wrapped. For many print margarines, a combin-

ation of vegetable parchment paper and aluminum

foil is often used to make a final print product in a

unit such as the Benhil. Popular soft margarines are

continuously packed in tubs usually made from poly-

vinylchloride. The filled product is then automatic-

ally packed into cases, sealed, and sent to a tempering

room. Packaged margarines should be stored at

5–10



C for 48 h before shipment from the ware-

house. This will ensure that the desired b

crystals

have sufficient time to multiply and reach a stable

state.

MARGARINE/Methods of Manufacture 3713