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Characteristics of raspberry (Rubus idaeus L.) seed oil


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Studies were conducted on properties of oil extracted from raspberry seeds. Oil yield from the seed was 10.7%. Physicochemical properties of the oil include: saponification number 191; diene value 0.837; p-anisidine value 14.3; peroxide value 8.25 meq/kg; carotenoid content 23 mg/100 g; and viscosity of 26 mPa.s at 25°C. Raspberry seed oil showed absorbance in the UV-B and UV-C ranges with potential for use as a broad spectrum UV protectant. The seed oil was rich in tocopherols with the following composition (mg/100 g): [alpha]-tocopherol 71; [gamma]-tocopherol 272; [delta]-tocopherol 17.4; and total vitamin E equivalent of 97. The oil had good oxidation resistance and storage stability. Lipid fractionation of crude raspberry seed oil yielded 93.7% neutral lipids, 3.5% phospholipids, and 2.7% free fatty acids. The main fatty acids of crude oil were C18:2 n-6 (54.5%), C18:3 n-3 (29.1%), C18:1 n-9 (12.0%), and C16:0 (2.7%). The ratio of fatty acids, polyunsaturates to monounsaturates to saturates varied depending on lipid fraction. Polymorphic changes were observed in thermal properties of raspberry seed oil.
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Characteristics of raspberry (Rubus idaeus L.) seed oil
B. Dave Oomah
*, Stephanie Ladet
, David V. Godfrey
, Jun Liang
, Benoit Girard
Food Research Program, Agriculture and Agri-Food Canada, Paci®c Agri-Food Research Centre, Summerland, British Columbia V0H 1Z0, Canada
E.N.S.A.M., E
Âcole Nationale Superieure Agronomique de Montpellier, 2, Place Pierre Viala, 34060 Montpellier Cedex 1, France
Shaanxi Fruit Crops Research Centre, Xi'an, Shaanxi 710065, China
Studies were conducted on properties of oil extracted from raspberry seeds. Oil yield from the seed was 10.7%. Physicochemical
properties of the oil include: saponi®cation number 191; diene value 0.837; p-anisidine value 14.3; peroxide value 8.25 meq/kg;
carotenoid content 23 mg/100 g; and viscosity of 26 mPa.s at 25C. Raspberry seed oil showed absorbance in the UV-B and UV-C
ranges with potential for use as a broad spectrum UV protectant. The seed oil was rich in tocopherols with the following compo-
sition (mg/100 g): a-tocopherol 71; g-tocopherol 272; d-tocopherol 17.4; and total vitamin E equivalent of 97. The oil had good oxi-
dation resistance and storage stability. Lipid fractionation of crude raspberry seed oil yielded 93.7% neutral lipids, 3.5% phospholipids,
and 2.7% free fatty acids. The main fatty acids of crude oil were C18:2 n-6 (54.5%), C18:3 n-3 (29.1%), C18:1 n-9 (12.0%), and C16:0
(2.7%). The ratio of fatty acids, polyunsaturates to monounsaturates to saturates varied depending on lipid fraction. Polymorphic
changes were observed in thermal properties of raspberry seed oil. #2000 Published by Elsevier Science Ltd. All rights reserved.
Keywords: Raspberry seed; Raspberry oil; Oil quality; Tocopherols; Storage; DSC; Chemical and physical parameters
1. Introduction
About 18,000 metric tonnes of raspberries are pro-
duced annually in Canada with the total global pro-
duction at 312 thousand metric tonnes. In the
processing of raspberry juice, the seed becomes a
byproduct which is currently under exploited. Oil from
raspberry seed could amount to over 400 metric tonnes,
assuming 10% of seed in fresh berries, 23% oil content
of seeds (Johansson, Laakso & Kallio, 1997) and that
all raspberry produced in Canada is processed as juice.
The composition of raspberry seeds compiled by Win-
ton and Winton (1935) reveals that as early as 1907 oil
expressed from the seed amounted to 14.6±18%. These
raspberry seed oils contained 0.73±1.10% phytosterol,
and had a saponi®cation value of 187±192. Recently,
Johansson et al. (1997) found that linoleic, a-linolenic,
oleic and palmitic acids were typically the most abun-
dant fatty acids from seed oil of 22 common edible wild
northern berries, including raspberry. The seed mass,
100 seed weight, and seed oil content for raspberry were
10.1% (fw), 180 mg, and 23.2%, respectively.
Storage studies by Carnat, Pourrat and Pourrat
(1979) showed that raspberry seed oil oxidized very
slowly even at 60C with an increase in peroxide value
from 3 to 39 mmol/kg over 7 days. At ambient tem-
perature (22±23C), oxidation was slower yet, with per-
oxide values varying from 3 to 18 mmol/kg after 5
weeks. This resistance to oxidation of raspberry seed oil
was purported to be due to the presence of a minor
component in the unsaponi®able fraction of the oil
(Carnat et al.). In the quest to understand the oxidative
stability of raspberry seed oil, Pourrat and Carnat
(1981) stabilized the moisture content of raspberry seed
to 5±6% by drying at 50C for 4±5 h, then extracted oil
with chloroform. The oil yield was 16±18% by that process
chloroform extracted oil was: C16:0, 2.7; C18:0, 0.2; C18:1,
18.7; C18:2, 55.5; and C18:3, 32.6 (Pourrat & Carnat,
1981). The de®nitive reason for the high stability of rasp-
berry seed oil has not been fully clari®ed.
The incorporation of raspberry seed oil in cosmetics
and pharmaceutical products based on its anti-in¯am-
matory activity notably for the prevention of gingivitis,
rash, eczema, and other skin lesions has been patented
(Pourrat & Pourrat). The anti-in¯ammatory activity of
raspberry seed oil was superior compared to those of
other well-known oils such as virgin avocado oil, grape-
seed oil, hazelnut oil, and wheat germ oil (Pourrat &
0308-8146/00/$ - see front matter #2000 Published by Elsevier Science Ltd. All rights reserved.
PII: S0308-8146(99)00260-5
Food Chemistry 69 (2000) 187±193
Paci®c Agri-Food Research Centre contribution no. 2017.
* Corresponding author. Tel.: +1-250-494-6399; fax: +1-250-494-
E-mail address: (B.D. Oomah).
Pourrat). According to this patent, raspberry seed oil can
be used as a sun screen, in toothpaste, cremes for pre-
vention of skin irritations, bath oil, aftershave cream,
antiperspirants, shampoos, and lipsticks.
Red raspberry forms part of the Paci®c Agri-Food
Research Centre small fruit breeding program. In addi-
tion to the release of new cultivars with high yields of
large fruits with excellent quality, pleasant ¯avor, ®rm
fruit and low susceptibility to pre- and postharvest dis-
eases, there is interest in the complete utilization of the
fruit for food and non-food uses. Raspberry seed oil may
be regarded as a speciality oil and as such may attract
considerable attention because of its possible nutraceu-
tical eects. It is a rare commodity and currently retails
at $52 a litre as a fragrant oil. Our aim is to transform
raspberry seed into economically valuable ingredients
for the food and nonfood industries. In this context, the
chemical and physical properties of oil extracted from
raspberry seed has been investigated to provide guide-
lines for innovative uses of this byproduct. The proper-
ties of raspberry seed oil was also compared with those
of two commercial oils, grapeseed and saower oils used
in the food, cosmetic and pharmaceutical industries.
2. Materials and methods
Raspberry (Rubus idaeus L.) seeds from a mixture of
dierent cultivars grown for processing were obtained
from Valley Berry Inc., (Abbotsford, British Columbia).
Since the moisture content of the seed was about 41.5%,
the seed samples were air-dried in a ¯uid bed dryer
(Lab-Line Instruments Inc., Melrose Park, IL) for 2 h at
25C to reduce the moisture to 13.6%. Raspberry seeds
were ground (Thomas Wiley Mill, Philadelphia, PA) to
pass a 1mm screen. Oil from milled samples was
extracted using hexane as described by Oomah, Mazza
and Przybylski (1996). Brie¯y, the sample (100 g) was
stirred for 2 h at 4C with hexane (1 l). The solvent was
removed by vacuum ®ltration and the sample was fur-
ther extracted twice. After the last ®ltration, the extract
was pooled, hexane removed (vacuum rotary evapora-
tion, 35C), purged with nitrogen and stored at ÿ20C
until analysis. A sample of raspberry seed was hydrau-
lically pressed (Carver Press, 280 kg/cm
) to extract
cold-pressed oil. A commercial grapeseed oil produced
and packed in Spain (Aceitas Borges Pont, S.A., Cata-
lonia) and saower oil (P.C.
Product, Sunfresh Ltd.,
Toronto, Canada) purchased from a local food store
were used as controls.
2.1. Analytical procedures
Ocial methods (American Oil Chemists' Society,
AOCS, 1993) were used for the determination of the
saponi®cation value (method Cd 3-25) and p-anisidine
value (method Cd 18-90) of oils. Conjugated dienoic
and trienoic acids were determined by the spectro-
photometric method outlined in the Standard Methods
for the Analysis of Oils, Fats and Derivatives (Interna-
tional Union of Pure and Applied Chemistry, IUPAC,
1985). The peroxide value of the oils was determined
using the PeroXOquant quantitative peroxide assay kit
(Pierce, Rochford, IL, USA). Absorptivity and trans-
mission of oil solutions (0.1± 10% v/v) in hexane were
measured with a spectrophotometer (DU-640B, Beckman
Instruments Inc., Fullerton, CA, USA).
The AOAC method (958.05, Association of Ocial
Analytical Chemists, AOAC, 1990) with a few mod-
i®cations was used to evaluate carotenoid content of
oils. Carotenoid content, expressed as micrograms of b-
carotene per gram of oil, was performed by applying a
calibration curve constructed by preparing solutions of
increasing concentration, from 0.5 to 2.5 mgofb-car-
otene/ml hexane. Absorbance was recorded at 440 nm
(DU-640B, Beckman Instruments Inc., Fullerton, CA,
USA) using hexane as blank. Oil was diluted with hexane
(10% v/v for grapeseed and saower, 1% v/v for rasp-
berry) to b-carotene standard range. Moisture content
was determined by the AOAC method (AOAC, 1984).
Viscosity of the oil was measured with a controlled stress
Bohlin rheometer CVO (Bohlin Instruments Ltd.,
Gloucestershire, UK). Measurements were performed at
25C with a steel cone-plate geometry (20 mm, 2) under
a ramping shear of 2.5±10 Pa.
Tocopherols were analyzed by an HPLC system
(Waters 840 system, Milford, MA, USA) consisting of a
pump (Model 510), an autosampler (Model 712) and a
¯uorescence detector (McPherson SF-749 spectro-
¯uorometer, Acton, MA, USA) interfaced with a per-
sonal computer. A normal phase column (4.6150 mm,
Primesphere 5 silica 5 mm) with guard column (4.630
mm) (Phenomenex, Torrance, CA, USA) was used with
hexane/2-propanol/dimethyl propane (1000/5/1, v/v/v)
as a mobile phase. The system was operated iso-
cratically at a ¯ow rate of 1 ml/min. Separations were
carried out at 25C (Waters TCM temperature con-
troller) with the ¯uorescence detector excitation and
emission wavelengths set at 297 and 325 nm, respec-
tively. Typically, a 10 min equilibration period was used
between samples, requiring about 40 min/sample.
Quantitation was based on an external standard
method; the calibration curves ranged from 3.97 to
15.87, 5.41 to 21.63 and 6.0 to 24.0 mg/ml of reference
compounds a-, d-, and b-, g-tocopherols, respectively
(Sigma Chemical Co., St Louis, MO, USA). Prior to
HPLC analysis, the oil was diluted with hexane to
obtain a concentration of about 160 g/l, ®ltered (0.45
mm, Gelman Science Inc., Ann Arbor, MI, USA) and 20
ml sample was injected.
Crystallization and melting points were measured
with a dierential scanning calorimeter (DSC-2910
188 B.D. Oomah et al. / Food Chemistry 69 (2000) 187±193
Modulated DSC-TA Instruments, New Castle, DE, USA).
Oil (20±25 mg) was weighed in DSC-pan (aluminium
open pan, TA Instruments T70529) and DSC runs were
performed within the temperature range of 10 to
ÿ70C. A programmed cycle was followed in which the
sample was cooled from 10 to ÿ70Cat1
maintained at this low temperature for 5 min and
heated back to 10C. An empty DSC pan was used as
an inert reference to balance the heat capacity of the
sample pan. The DSC was calibrated for temperature
and heat ¯ow using mercury (mp ÿ38.83C, TA Instru-
ments standard), distilled water (mp 0.0C), gallium
(mp 29.76C, TA Instruments standard) and indium
(mp 156.6C, 28.71 J/g, Aldrich Chemical Co.).
Separation of individual lipid classes was performed
using solid-phase extraction cartridge, (Bakerbond
amino [NH2] disposable extraction column, 500 mg, J.
T. Baker Inc., Phillipsburg, NJ), with aminopropyl
packing, essentially as described by Carelli, Brevedan
and Crapiste (1997). The cartridge was preconditioned
with 2 ml methanol, 2 ml chloroform, and 4 ml hexane
before use. A micropipet was used to inject 50±150 mg
of oil dissolved in chloroform. Lipid classes were
recovered by sequential elution under vacuum (5±10
mm Hg) with 4 ml each of chloroform/isopropanol (2/1,
v/v), diethyl ether/acetic acid (95/5, v/v), and methanol
to separate neutral lipids, free fatty acids and phospho-
lipids, respectively. The eluates were collected, evapo-
rated under nitrogen, weighed, and stored at ÿ20C for
fatty acid analysis.
The lipids were esteri®ed by the one-step methylation
method of Ulberth and Henninger (1992) with some
modi®cations. These included the omission of toluene in
the reagent and centrifugation for phase separation. The
top layer was transferred into a small vial and dried
with anhydrous Na
. Samples were analyzed for
their fatty acid methyl esters on a Hewlett±Packard
model 5890 gas chromatograph (Avondale, PA), equip-
ped with a split/splitless injector, a ¯ame-ionization
detector, an automatic sampling device, and a 100 M
SP-2560 fused-silica capillary column (Supelco, Oak-
ville, ON) with 0.25 mm i.d. The column temperature
was programmed from 140 to 240Cat4
C/min, and
the injector and detector temperatures were set at
260C. Helium was the carrier gas. Peak areas of dupli-
cate injections were measured with a Hewlett±Packard
3396 computing integrator. All assays except thermal
analysis were performed in triplicates.
3. Results and discussion
Raspberry seed at 13.6% moisture content had a yield
of about 10.7% (db) oil by solvent extraction. Our oil
yield was at the lower end of the seed oil content for
Rubus species (10±23% dw) reported by Johansson et al.
(1997), and lower than (14±18%) those reported earlier
for raspberry seed (Pourrat & Carnat, 1981; Winton &
Winton, 1935). The lower oil yield obtained in this
study could be partly due to dierent seed samples and
solvent used for oil extraction. Raspberry seed oil is
yellow with a slight ``®shy'' o-note. Crude raspberry
seed oil showed some absorbance in the UV-C (100±290
nm) and UV-B (290±320 nm) range (Fig. 1). In the UV-
B range, the wavelengths of ultraviolet light responsible
for most cellular damage, raspberry seed oil can shield
against UV-A induced damage by scattering (high
transmission), as well as by absorption. The shielding
power in the UV-A (320±400 nm) range depends mostly
on the scattering eect. Thus, raspberry seed oil may act
as a broad spectrum UV protectant and provide pro-
tection against both UV-A, an exogenous origin of oxi-
dative stress to the skin, and UV-B. The optical
transmission of raspberry seed oil, especially in the UV
range (290±400 nm) was comparable to that of titanium
dioxide preparations with sun protection factor for UV-
B (SPF) and protection factor for UV-A (PFA) values
between 28±50 and 6.75±7.5, respectively (Kobo Pro-
ducts Inc., South Plain®eld, NJ).
Absorptivity at 245 nm, a wavelength which is
approximately at the lower limit of detectability for the
Fig. 1. Ultra violet/visible spectra of raspberry seed oil. Figure derived
from scans (l=200±290) of oil diluted 1:100; from scans (l=290±400
and l=400±800) of oil diluted 1:10, all in hexane. Black line is absor-
bance and gray line is transmission.
B.D. Oomah et al. / Food Chemistry 69 (2000) 187±193 189
human eye, was low for raspberry seed oil, inferring low
levels or absence of yellow pigments in the oil. Green
pigments, particularly chlorophyll content, usually
measured at 630, 670 and 710 nm, was negligible as
indicated by very low absorbance (0.003±0.007) in the
600±750 nm range for raspberry seed oil (1% oil in
hexane). The negligible amount of green pigments does
not impart undesirable color to the oil and may be
unable to promote oil oxidation, especially in the pre-
sence of light. Raspberry seed oil contained yellow col-
oring as indicated by absorbance between 0.084 and
0.108 at 440±460 nm for 1% oil in hexane and was
equivalent to the Munsell 1.25 Y 8/16 rating. These
yellow colors which include carotenoids are bene®cial,
since they simulate the appearance of butter without the
use of primary colorants such as carotenes, annatos,
and apocarotenals commonly used in the oil and fat
industry. Actual carotenoid content of raspberry seed
oil was 23 mg/100 g of oil (Table 1).
Raspberry seed oil has a low viscosity (Table 1), a
characteristic which may render it less occlusive than
hydrocarbon oils. The viscosity of raspberry seed oil
was lower than most vegetable oils and similar to that of
oleic acid (Noureddini, Teoh & Clements, 1992). Con-
jugated diene value of the seed oil was 0.837, and sig-
ni®cantly higher than those of commercial grapeseed
and saower oils analyzed under the same conditions.
This dierence is likely due to raspberry seed oil's high
18:3 content compared to the two commercial oils.
Conjugated triene was not detected in raspberry seed oil
suggesting absence or very low levels of linolenate oxi-
dation in oil. p-Anisidine value of the oil was 14.3 and
signi®cantly higher than those of the commercial oils,
indicating the presence of aldehydic carbonyl com-
pounds or secondary oxidation of the raspberry seed
oil. The peroxide value was 8.25 meq/kg oil, and lower
than those generally recommended for commercial
vegetable oils (410). However, the oil hydroperoxides
can be substantially lowered or reduced during bleach-
ing with acid-activated bleaching earth. The total oxi-
dation value (totox) of raspberry seed oil, calculated
using the peroxide and anisidine values (2Px+Av), was
30.8, and comparable to that of encapsulated ®sh oil,
but higher than those of vegetable oils (Shukla & Per-
kins, 1998). Raspberry seed oil was twice as prone to
auto-oxidation as saower oil (totox value of 12.4)
under the same test conditions. The saponi®cation value
of raspberry seed oil was high and comparable to those
of common vegetable oils indicating very high content of
low molecular weight triacylglycerols. It was similar to
the saponi®cation value of canola oil (Eskin et al., 1996)
and within the values for raspberry seed oil (187±192)
reported previously (Winton & Winton, 1935). Rasp-
berry seed oil may be prone to peroxide formation
based on its peroxide value and may be suitable for soap
production judging from the high saponi®cation value.
The major tocopherol in raspberry seed oil was the g
isomer at 75% of the total tocopherol. a- and d-Toco-
pherol contents of the oil were 71 and 17.4 mg/100 g,
respectively (Table 2). The a- and d-tocopherol levels of
Table 1
Physicochemical characteristics of raspberry, saower and grape seed
Raspberry Saower Grape
Oil yield Ð
dry matter (%)
Seed moisture (%) 13.60.1
Viscosity (mPas.s)
261.1 47.30.4 49.40.3
1910.1 191.60.6 192.90.4
Diene value 0.8370.0003 0.5140.006 0.4670.001
Triene value
0.1340.006 0.0890.001
p-Anisidine value 14.30.2 5.360.006 10.460.03
Peroxide value
8.250.1 3.520.04 0.960.01
Carotenoid content
(mg/100 g)
Means of 3.
Means of 10 measurements over ramping stress range (2.5 to 10 Pa).
Not applicable.
Not detected.
Table 2
Tocopherol contents of raspberry, saower and grape seed oils (mg/100 g)
Tocopherol Tocotrienol
abg dagTotal Vitamin E
Hexane extracted 710.5
2722.6 17.40.5
3603.6 970.8
Cold pressed 46.12.2
14411.7 7.10.7
19813.2 613.3
Saower 56.00.09 2.00.2 1.10.1
59.01.0 570.9
Grape 5.60.0 2.30.0 3.30.3
15.70.2 28.50.5 55.40.9 11.80.1
Means of 2.
Not detected.
190 B.D. Oomah et al. / Food Chemistry 69 (2000) 187±193
cold-pressed raspberry seed oil was about half that of
the hexane-extracted oil. The reason for this dierence
is unclear, but could probably be due to the presence of
non-lipid material in cold-pressed oil which may dilute
the concentration of tocopherols. The biologically
active vitamin E content relative to that of a-toco-
pherol, calculated by using the formula proposed by
McLaughlin and Weihrauch (1979), were 97.8 and 58.4
mg/100 g for the hexane-extracted and cold-pressed oils,
respectively. Raspberry seed oil is a very rich source of
gamma tocopherol since its level (137±272 mg/100 g) is
much higher than those reported for other vegetable oils
and foods (Eskin et al., 1996; McLaughlin & Weihrauch).
The ratio of the tocopherol isomers a:g:din raspberry
seed oil was 20:75:5, and resembled that in commercial
re®ned corn oil at 17:78:3 (McLaughlin & Weihrauch,
1979). The high g-tocopherol concentration of rasp-
berry seed oil may exert a signi®cant biological eect in
non-ruminant animals since g-tocopherol concentration
is easily detected in animals fed natural source of toco-
pherols at concentrations of 100 and 1000 ppm (Eng-
berg, Jakobsen & Hart®el, 1993). Raspberry seed oil with
high levels of g-tocopherol may be as important as a-
tocopherol in the prevention of degenerative diseases.
Storage studies carried out at 37C in the dark
showed similar trends of increase in peroxide value with
time for raspberry and saower oils (Fig. 2). However,
the rate of increase in peroxide value for raspberry seed
oil was lower than that of saower oil. The data
describing the rate of autoxidation ®tted the poly-
nominal model (y=ax
+bx+c). The coecients of
regressions (R
) between the peroxide value and storage
time were 0.808 and 0.864 (P<0.05) for raspberry and
saower oils, respectively. At the end of the storage
period (240 h) both oils were roughly equivalent in
terms of oxidative degradation that had occurred. A
clear induction period was not observed in this study,
even when the storage period was extended to 900 h
(data not shown). Similar observations have been
reported for raspberry seed oil stored at ambient (22±
23C) temperature for 5 weeks (Carnat et al., 1979).
Raspberry seed oil consisted primarily of neutral lipid
(93.8%) with minor amounts of free fatty acid and
phospholipids (3.5 and 2.7% of the total crude oil,
respectively) (Table 3). Similar high levels of neutral
lipids (95.7±95.9%) have been reported for raspberry
seed oil (Winton & Winton, 1935), and other berry fruit
Fig. 2. Stability of raspberry seed oil at 37C evaluated as peroxide value. *=raspberry seed oil, &=saower seed oil.
Table 3
Fatty acid composition of raspberry seed oil
Composition (mass%)
Fatty acid Crude oil
Free fatty
Fractions (%)
93.72.0 3.51.13 2.73.1
C16:0 2.690.14 2.68 10.46 10.92
C18:0 0.970.01 1.02 1.26
C18:1 11.990.01 12.11 26.62 19.24
C18:2 54.520.10 55.12 47.28 63.55
C18:3 29.110.05 28.74 14.35 6.29
Means of 4.
Means of 2.
Not detected.
B.D. Oomah et al. / Food Chemistry 69 (2000) 187±193 191
oils such as sea buckthorn seed oil (92%) (Zadernowski,
Nowak-Polakowska, Lossow, Nesterowicz, 1997). The
phospholipid content of raspberry seed oil at 2.7% was
higher than that of fruit stone oils from the Rosaceae
species (0.4±1.1% for peach, apricot, and cherry seed
oils) at the expense of neutral lipids (97.2±98.7%) (Zla-
tanov & Janakieva, 1998). Raspberry seed oil had higher
free fatty acid content but comparable phospholipid
content than those of common edible oils (canola, soy-
bean, sun¯ower, corn) 0.3±1.8%, and 0.2±4.0%, respec-
tively. For edible purposes, these non-triglycerides
components are considered detrimental to oil quality
and should be removed through processing.
The phospholipids are useful as emulsi®ers in food
and pharmaceutical applications. In raspberry seed oil,
the phospholipids may act as a natural antioxidant
Â& Pokorny, 1995) and consequently increase
oil stability and shelf life.
The most abundant fatty acids of raspberry seed oil
were linoleic, a-linolenic, and oleic acids, which together
comprised 96% of the total fatty acid. The fatty acid
composition of raspberry seed oil was similar to that
reported previously (Pourrat & Carnat, 1981) and to
that of Rosa dumalis (Johansson et al., 1997). The lino-
leic acid content of raspberry seed oil was similar to that
of walnut oil (56±59%) (Ruggeri, Capelloni et al., 1998).
Neutral lipids which constituted about 94% of the total
lipids, had fatty acid composition similar to that of
crude raspberry seed oil. The phospholipid fraction was
richer in saturated and monounsaturated fatty acids (11
and 19% of the total fatty acid, respectively), but much
lower in polyunsaturates compared to the neutral lipid
fraction. The polyunsaturates of the free fatty acid
fraction amounted to only 61% of the total fatty acids,
while the monounsaturated and saturated fatty acids
amounted to 27 and 12%, respectively. Hence, the ratio
of polyunsaturates to monounsaturates to saturates
varied from 84:12:4 to 61:27:12, depending on lipid
fractions. The crude raspberry seed oil and the neutral
lipid fraction were particularly low in palmitic acid.
They contained high amounts of linolenic acid, which
makes them especially prone to oxidation, but which
may have favorable nutritional implications and bene-
®cial physiological eect in the prevention of coronary
heart disease and cancer (Oomah & Mazza, 1998). The
free fatty acid and phospholipid fractions with lower
levels of linolenic acid than the neutral fraction renders
them less susceptible to oxidation. The neutral lipid
fraction was characterized by the highest poly-
unsaturated/saturated (P/S) ratio of 22.7, while those of
free fatty acids and phospholipid fractions were 15.3
and 6.4, respectively. A high ratio of P/S is regarded
favorably in the reduction of serum cholesterol and
atherosclerosis and prevention of heart diseases (Rudel,
Kelly, Sawyer, Shah & Wilson, 1998). Similarly, the
ratio of n-6 to n-3 fatty acids were 1.92, 3.29 and 10.10
for the neutral, free fatty acid and phospholipid frac-
tions, respectively.
Raspberry seed oil has unique thermal characteristics
(Fig. 3). The oil presented a crystallization peak
atÿ62C with enthalpy of 38.3 J/g. Polymorphism was
detected in raspberry seed oil: after melting of the low
temperature modi®cation at ÿ45C, an additional
modi®cation crystallized with an exothermic peak at
ÿ43C. At ÿ23C, peak temperature, this modi®cation
melted with an originally existing crystallite of the same
kind. Similar DSC tracings were observed for grapeseed
oil in this study and by Kaisersberger (1990) and saf-
¯ower oil (data not presented). These polymorphic
changes can be hindered by addition of emulsi®ers (Kai-
sersberger). According to Garti, Schlichter and Sarig
(1988), the ®rst small endothermic peak at ÿ45C repre-
sents the melting of the unstable acrystal form followed
by the crystallization of the more stable bform which is
characterized by an exothermic peak. The melting
enthalpy of raspberry seed oil was 75 J/g. The amount of
melting according to DSC determinations (ratio of enthal-
pies) was 50.9%, i.e. the solid±liquid ratio of approxi-
mately 1:1 at ÿ23C. This solid±liquid ratio and, melting
and recrystallization characteristics of raspberry seed oil
can impinge on its consistency, taste and texture.
The potential for production of oil as a byproduct of
raspberry seed appears to be excellent. The unique fatty
acid composition, high tocopherol content and quality
and hence high protection against oxidative stress, rela-
tively good shelf life, and other desirable physicochem-
ical characteristics indicate potential uses of raspberry
seed oil in food, pharmaceutics, cosmetics, and other
nonfood industries. The microconstituents of raspberry
seed oil with its rich array of phytochemicals, especially
the omega-3 fatty acids and tocopherols suggest that it
is a nutraceutical and may be marketed as a dietary
supplement with a structure/function claim about heal-
thy blood circulation. The production of oil from rasp-
berry seed provides the use of a renewable resource, and
at the same time adding value to agricultural products
and improving the environment.
Fig. 3. DSC pro®le of raspberry seed oil.
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... Studies focusing on the method of extraction and general characteristics of raspberry seed oil were previously reported (Oomah et al., 2000;J. Parry and Yu, 2004;Pavlić et al., 2020). ...
... Finally, at the long wave range of the spectrum, the spectra with maxima at 670 nm indicates the presence of chlorophyll pigments, although the peaks from samples were barely seen, which can indicate that they will not act as prooxidants in the presence of light. Generally, the measured UV/Vis spectra of cold-pressed oil from raspberry seeds were similar to that presented by Oomah et al. (2000). However, the spectra presented in this study, exhibit differences between samples in the aforementioned regions, first of all, indicating differences in the concentrations of compounds. ...
... The thermal properties of raspberry seed oils were measured at scanning rates 1, 2, 5 • C/min (Fig. 3). Generally, the thermal profile of raspberry seed oils from L-group and sample I3 are similar with melting and crystallization profiles of the same oil reported in other studies (Micić et al., 2015b;Oomah et al., 2000). The similarities were mainly found in the peak temperatures of melting (T m1 = ± − 45 • C, T m2 = ± − 43 • C, T m3 = ± − 23 • C) and crystallization (T c = ± − 62 • C) curves at 1 • C/min (Oomah et al., 2000). ...
... J/g, respectively. The two peaks showed a distinctive difference in intensity and could be due to the wide variation in fatty acid components of the OS bio oil (Saloua et al., 2009;Oomah et al., 2000). However, the appeared two peaks of the OS bio oil at 34 • C and 249.99 • C represent an endo transition peak indicating the oxidative degradation of the sample (Besbes et al., 2004). ...
... However, the appeared two peaks of the OS bio oil at 34 • C and 249.99 • C represent an endo transition peak indicating the oxidative degradation of the sample (Besbes et al., 2004). These two peaks suggests the interactions between the hydrophilic and hydrophobic components of the fatty acid methyl ester (Saloua et al., 2009;Oomah et al., 2000). ...
... Apart from the biological components contained in the dry matter of the berries' leaves, raspberry seed oil is a known source of valuable bioactive components [22,31]. Seed oil is extracted via a hydro-distillation, maceration, or cold-pressing technique. ...
... The quality and concentration of the substances highly depend on the type of raspberry, the cultivation region, and the oil extraction technique. The raspberry seed oil contains a high amount of polyunsaturated fatty acids, tocopherols, polyphenols, and p-anisidine [31]. This unique content of various bioactive molecules makes the oil a source of ingredients for food, or for the cosmetics and pharmaceutics industries. ...
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The gestational period is an incredibly stressful time for a pregnant woman. Pregnant patients constantly seek effective and reliable compounds in order to achieve a healthy labor. Nowadays, increasing numbers of women use herbal preparations and supplements during pregnancy. One of the most popular and most frequently chosen herbs during pregnancy is the raspberry leaf (Rubus idaeus). Raspberry extracts are allegedly associated with a positive effect on childbirth through the induction of uterine contractions, acceleration of the cervical ripening, and shortening of childbirth. The history of the consumption of raspberry leaves throughout pregnancy is vast. This review shows the current status of the use of raspberry leaves in pregnancy, emphasizing the effect on the cervix, and the safety profile of this herb. The majority of women apply raspberry leaves during pregnancy to induce and ease labor. However, it has not been possible to determine the exact effect of using raspberry extracts on the course of childbirth and the perinatal period. Additionally, it is unclear whether this herb has only positive effects. The currently available data indicate a weak effect of raspberry leaf extracts on labor induction and, at the same time, their possible negative impact on cervical ripening.
... Linoleic acid prevents coronary heart disease and cancer and provides lipids necessary for cell membrane repair and cellular respiration (Oomah et al., 2000). The ratio of total saturation to total unsaturation in both LFFA CPO and HFFA CPO was found to be 1:1 (Table 4). ...
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Quality of palm oil determines its consumer and market acceptability and price. This correlates directly to its moisture (%), free fatty acid (% FFA) and total fatty matter (%TFM) content. The aim of the present study was to evaluate the quality of low free fatty acid (LFFA) and high free fatty acid (HFFA) crude palm oil (CPO) samples aged 5 to 10 days, purchased from four locations in Southern Nigeria. HFFA CPO is produced using traditional methods while LFFA CPO is produced by modern milling methods. The oil samples were analyzed for quality and fatty acid using standard analytical methods. The results obtained showed that FFA and total contaminants were significantly (p<0.05) lower in LFFA and higher in HFFA CPO samples. The values of FFA were significantly (P<0.05) higher in HFFA (9.25±0.70-12.76±1.20%) when compared to LFFA CPO values (2.44±0.30-2.95±0.08%). No significant (p>05) difference was observed in the mean saponification value of LFFA (198.95±0.80 mg KOH/g oil) and HFFA CPO (198.62±0.40 mg KOH/g oil). TFM for LFFA CPO ranged between 91.94±0.40-92.45±0.75% suggesting no significant (p>0.05) variability in TFM values for LFFA CPO. TFM values for HFFA CPO were significantly (P<0.05) lower and varied between 81.06±0.64 and 85.16±1.05%. The palmitic acid in HFFA CPO was 44.670±0.85 and 45.641±1.77% in LFFA CPO. Oleic acid content was 37.370±0.92% in HFFA oil and 39.005±1.06% in LFFA oil. It was concluded that CPO is rich in SFAs, MUFAs and PUFAs. The ratio of TSFAs to TUFAs for both LFFA and HFFA CPO is 1:1.
... Linoleic acid prevents coronary heart disease and cancer and provides lipids necessary for cell membrane repair and cellular respiration (Oomah et al., 2000). The ratio of total saturation to total unsaturation in both LFFA CPO and HFFA CPO was found to be 1:1 (Table 4). ...
... Because of its high linoleic acid content, A. tenuifolius seed oil was particularly susceptible to oxidation. However, this compound may have advantageous nutritional and physiological effects in the prevention of cancer and both coronary heart disease (Oomah et al., 2000). ...
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In this study, Asphodelus tenuifolius (ATO) seeds oils were extracted by three different extraction methods, namely Soxhlet extraction (SE), microwave-assisted extraction (MAE) and ultrasonic-assisted extraction (UAE). The physicochemical properties, fatty acids, sterols, tocols, total phenol content and antioxidant activity of ATO seed were examined and compared. The best extraction yield was from SE (21.97 ± 0.01%), followed by MAE (19.28 ± 0.13%) while that of UAE was the lowest (16.5 ± 0.1%). Analysis of the chemical composition of these oils showed that linoleic acid and β-sitosterol were the main fatty acid and sterol compounds, respectively. A large amount of fatty acids and sterols were not significantly affected by the three extraction methods. Nevertheless, the tocols, the total phenols contents and the antioxidant power showed a variation between these three extracted oils. Based on these results, it was found that this specie has great potential for industrial use.
... ISO official methods were used to determine PV [60], AnV [61] and conjugated dienes and trienes [62] of oil samples. The total oxidation index (totox) was calculated using the following equation (1) [63,64]: ...
Background: In this work, the chemical composition analysis was performed for cold pressed oils obtained from the 15 sunflower hybrids grown in Serbia and Argentina, as well as the determination of their oxidative quality. The fatty acid composition and bioactive compounds including total tocopherols, phenols, carotenoids, and chlorophyll contents were investigated. The oxidation products were monitored through the peroxide value (PV), anisidine value (AnV), conjugated dienes (CD) and conjugated trienes (CT) content, and total oxidation index (TOTOX) under accelerated oxidation conditions by the oven method. Results: Linoleic acid was the most abundant fatty acid in investigated oil samples, followed by oleic and palmitic acids. The mean contents of total tocopherols, phenols, carotenoids, and chlorophyll were 518.24, 9.42, 7.54 and 0.99 mg/kg, respectively. In order to obtain an overview of sample variations according to the tested parameters Principal Component Analysis (PCA) was applied. Conclusion: PCA indicated that phenols, chlorophyll, linoleic and oleic acid were the most effective variables for the differentiation of sunflower hybrids grown in Serbia and Argentina. Furthermore, based on the fatty acid composition and bioactive compounds content in the oils, a new Artificial Neural Network (ANN) model was developed to predict the oxidative stability parameters of cold pressed sunflower oil.
... For example, raspberry and blackberry oil densities were 926.3-929 kg/m 3 [34] and 925.6 kg/m 3 [35], respectively. On the other hand, raspberry oil dynamic viscosity is of the lower value (26 mPa s, [36]) while strawberry values were 41.7 mPa s, at 20 °C using a rotary viscometer (this study) and 300 mPa s, at 20 °C and a shear rate of 50 s -1 [17] determined with a rheometer. ...
Strawberry pomace is the beverage industry waste and should be utilized as circular economy feedstock, animal feed, or a fertilizer following environmental regulations. This work aimed to characterize and implement strawberry pomace oil in the biodiesel industry. Oil was extracted from the strawberry seed by a maceration method for physicochemical characterization. Two seed/solvent ratios were used to achieve the maximum oil yield. The yield of strawberry seed oil by n-hexane extraction at the seed/solvent ratio of 1:3 was 0.11 g/g. Extracted strawberry oil was used for biodiesel production by a two-step process that included the acid (H 2 SO 4)-catalyzed pre-esterification of strawberry oil, followed by the base (KOH)-catalyzed transesterification of the pre-esterified strawberry oil. Further, the methanolysis ensured a biodiesel content of 97.2% in 30 min. However, the low yield of this technology's final product and physicochemical characterization showed that strawberry oil should be used in a mixture with other oils (hybrid oil) for biodiesel production, or in the cosmetics and food industry.
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In recent years, there was an increase in the commercial offer of vegetable oils from unconventional sources, such as fruit, vegetable, and herb seeds. The paper presents a synthesis of available scientific information on 27 oils obtained from the seeds of 14 fruit species (apple, apricot, chokeberry, black berry, blackcurrant, blue berry, cherry, Japanese quince, pear, plum, quince, raspberry, rosehip, and strawberry), 8 vegetable species (broccoli, cabbage, carrot, cucumber, onion, parsley, radish, and tomato), and 5 herb species (basil, coriander, fennel, fenugreek, and perilla). A review of the literature showed that oil content in these seeds ranges from ca. 5% for fenugreek to over 55% for apricot kernels. A recommended n-6/n-3 fatty acid ratio below 4-5/1 was noted in 11 species. Japanese quince, blackcurrant, and fenugreek seed oils seem to be good sources of phytosterols. Radish seed oil was mostly abundant in tocols, Japanese quince seed oil in squalene, and blackcurrant seed oil in carotenoids. Unfortunately, actual data on the composition of these seed oils are highly variable, making it difficult to precisely identify the most nutritionally valuable oils.
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An ultrasound-enzyme-assisted extraction (UEAE) was optimized to extract, simultaneously, the hydrophilic and lipophilic compounds from three berry pomaces (raspberry, strawberry and blackberry). First, an enzyme screening designated a thermostable alkaline protease as the most suitable enzyme to recover, in an aqueous medium, the highest yields of polyphenols and oil in the most efficient way. Secondly, the selected enzyme was coupled to ultrasounds (US) in sequential and simultaneous combinations. The simultaneous US–alkaline enzyme combination was selected as a one-single-step process and was then optimized by definitive screening design (DSD). The optimized parameters were: US amplitude, 20% (raspberry pomace) or 70% (strawberry and blackberry pomaces); pH, 8; E/S ratio, 1% (w/w); S/L ratio, 6% (w/v); extraction time, 30 min; temperature, 60 °C. Compared to conventional extractions using organic solvents, the UEAE extracted all the polyphenols, with around 75% of the active polyphenols (measured by the DPPH● method) and up to 75% of the initial oil from the berry pomaces. Characterized lipophilic compounds were rich in polyunsaturated fatty acids (PUFAs), tocols and phytosterols. The polyphenolics were analyzed by UPLC-MS/MS; characteristic ellagitannins of the Rosaceae family (sanguiin H-6 or agrimoniin, sanguiin H-10, …) and ellagic acid conjugates were found as the major components.
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Cultivars of almonds, hazelnuts, pecans, pistachios, walnuts grown in Italy and commercial samples of pine nuts were evaluated. Lipids were the main component: (from 50 to 74%) in all nuts, with oleic and linoleic acids representing more than 75% of the total fatty acids and linolenic acid in walnuts reaching 15%. Levels of saturated fatty acids were about: 10% in all nuts. Almond cultivars and pistachios were a good source of dietary fiber (up to 13%). Sucrose was the main sugar constituent; raffinose and stachyose were only found in hazelnuts, pine nuts and pistachios. The amino acid composition was similar in all the nuts with glutamic acid, arginine and aspartic acid accounting for about 40% of the protein. The Chemical Score ranged from 0.38 to 0.56, lysine being the limiting amino acid. Protein and lipid composition of walnut cultivars showed higher variability than almonds.
L'influence de la composition, de la teneur en eau, de la methode de preparation sur les caracteristiques des lipides (melange et congelation) est recherchee par calorimetrie differentielle a balayage. La methode permet de mettre en evidence l'oxydation des lipides dans certaines conditions
The phospholipid composition of five types of vegetable oil extracted from the nuts of plum (Prunus domestica L.), peach (Prunus persica L.), apricot (Prunus armeniaca L.), cherry (Prunus aviumL.), and morello-cherry (Prunus cerasus L.) was determined spectrophotometrically after fractionation and separation to individual components by means of two-directional thin-layer chromatography. The content of phospholipids in the oils varied from 0.4% to 1.1%, while in the corresponding nuts it varied from 0.2 to 0.5%. The major components in the phospholipid fraction were phosphatidylcholine (37.1–59.0%), phosphatidylinositol (13.8–31.6%) and phosphatidylethanolamine (12.9–19.5%). The fatty acid composition of the triacylglycerols and of the major phospholipids was determined by capillary gas chromatography. Larger quantities of saturated fatty acids, mainly palmitic and stearic acid, were identified in the phospholipids. Phospholipidzusammensetzung der Steinglyceridöle der Familie Rosaceae Mit Hilfe der zweidimensionalen Dünnschichtchromatographie wurde die Phospholipidzusammensetzung von fünf pflanzlichen Glyceridölen der Familie Rosaceae untersucht: Pflaume (Prunus domestica L.), Pfirsich (Prunus persica L.), Aprikose (Prunus armeniaca L.), Kirsche (Prunus avium L.) und Sauerkirsche (Prunus cerasus L.). Der Phospholipidgehalt der Glyceridöle beträgt 0,4% bis 1,1%, der Gehalt in den Früchten lag zwischen 0,2% und 0,5%. Die Hauptkomponenten der Phospholipidfraktion sind: Phosphatidylcholin 37,1%–59,0%, Phosphatidylinositol 13,8%–31,6% und Phosphatidylethanolamin 12,9%–19,5%. Die Fettsäurezusammensetzung der Glyceridöle und der Hauptkomponenten der Phospholipidfraktion wurde mittels Kapillargaschromatographie untersucht. Größere Mengen an gesättigten Fettsäuren, hauptsächlich Palmitin- und Stearinsäure, wurden in den Phospholipiden nachgewiesen.
The Polymorphism of saturated monoacid triglycerides C12–C18 in the presence of food emulsifiers was investigated using the differential scanning calorimetry. ΔHf values of α and β polymorphs in the presence and in the absence of emulsifiers were compared. Difference was found between the effects of the various emulsifiers in the diverse triglycerides. The change in ΔHf was correlated to the change in the proportion of the same polymorph which melts. The inhibition of β crystallization in C18 by solid emulsifiers is shown to be minimized at slower heating rates, confirming the kinetic effect of the surfactant on the α–β transition. DSC-Untersuchungen zur Polymorphie von gesättigten einsäurigen Triglyceriden in Gegenwart von in Nahrungsmitteln verwendeten Emulgatoren Es wurde mit Hilfe der Differentialthermoanalyse die Polymorphie von gesättigten einsäurigen Triglyceriden von C12–C18 in Gegenwart von in Nahrungsmitteln verwendeten Emulgatoren untersucht. Die ΔHf–Werte von α- und β- Formen wurden mit und ohne Emulgatoren verglichen. Es wurden Unterschiede in der Wirkung der verschiedenen Emulgatoren in den zahlreichen Triglyceriden gefunden. Die Änderung im ΔHf-Wert war korreliert mit der Änderung des Anteils der schmelzenden gleichen polymorphen Form. Die Hemmung der β-Kristallbildung in C18 durch feste Emulgatoren wird bei niedrigeren Heizraten verringert; dies bestätigt den kinetischen Effekt des Emulgators auf die α-β-Umwandlung.