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1.
A. G. Gopala Krishna K. H. Hemakumar Sakina Khatoon 《Journal of the American Oil Chemists' Society》2006,83(12):999-1005
Model oil systems containing physically refined rice bran oil to which oryzanol was added were examined to determine the effects
of oryzanol concentration on FFA values. When oryzanol was added to the model oils at a 0.5% level and FFA was determined,
increases in FFA value were 0.28% as determined with phenolphthalein, 0.58% with thymolphthalein, and 0.07% with alkali blue
6B. Oils containing added oryzanol at 0.5–1.5% showed a proportionate increase in FFA values with an average increase of 0.413%
per gram of oryzanol. A direct titration of purified oryzanol showed an acidity of 42.5% expressed as FFA. In spectroscopic
studies, the phenolic group in the ferulic acid moiety of oryzanol was titrated by sodium hydroxide. Based on these data,
indicator correction factors for oryzanol's acidity and a formula for calculating real FFA content of vegetable oils containing
oryzanol were developed. 相似文献
2.
Effect of refining of crude rice bran oil on the retention of oryzanol in the refined oil 总被引:3,自引:0,他引:3
A. G. Gopala Krishna Sakina Khatoon P. M. Shiela C. V. Sarmandal T. N. Indira Arvind Mishra 《Journal of the American Oil Chemists' Society》2001,78(2):127-131
The effect of different processing steps of refining on retention or the availability of oryzanol in refined oil and the oryzanol
composition of Indian paddy cultivars and commercial products of the rice bran oil (RBO) industry were investigated. Degumming
and dewaxing of crude RBO removed only 1.1 and 5.9% of oryzanol while the alkali treatment removed 93.0 to 94.6% of oryzanol
from the original crude oil. Irrespective of the strength of alkali (12 to 20° Be studied), retention of oryzanol in the refined
RBO was only 5.4–17.2% for crude oil, 5.9–15.0% for degummed oil, and 7.0 to 9.7% for degummed and dewaxed oil. The oryzanol
content of oil extracted from the bran of 18 Indian paddy cultivars ranged from 1.63 to 2.72%, which is the first report of
its kind in the literature on oryzanol content. The oryzanol content ranged from 1.1 to 1.74% for physically refined RBO while
for alkali-refined oil it was 0.19–0.20%. The oil subjected to physical refining (commercial sample) retained the original
amount of oryzanol after refining (1.60 and 1.74%), whereas the chemically refined oil showed a considerably lower amount
(0.19%). Thus, the oryzanol, which is lost during the chemical refining process, has been carried into the soapstock. The
content of oryzanol of the commercial RBO, soapstock, acid oil, and deodorizer distillate were in the range: 1.7–2.1, 6.3–6.9,
3.3–7.4, and 0.79%, respectively. These results showed that the processing steps—viz., degumming (1.1%), dewaxing (5.9%),
physical refining (0%), bleaching and deodorization of the oil—did not affect the content of oryzanol appreciably, while 83–95%
of it was lost during alkali refining. The oryzanol composition of crude oil and soapstock as determined by high-performance
liquid chromatography indicated 24-methylene cycloartanyl ferulate (30–38%) and campesteryl ferulate (24.4–26.9%) as the major
ferulates. The results presented here are probably the first systematic report on oryzanol availability in differently processed
RBO, soapstocks, acid oils, and for oils of Indian paddy cultivars. 相似文献
3.
P. M. Shiela Y. N. Sreerama A. G. Gopala Krishna 《Journal of the American Oil Chemists' Society》2004,81(12):1125-1129
The physicochemical characteristics and minor component contents of blended oils packed in pouches in relation to starting
oils used for blending were studied over a period of 6 mon at two storage temperatures and humidity conditions: 27°C/65% RH
and 40°C/30–40% RH. Color, PV, FFA value, β-carotene content, tocopherol content, and oryzanol content of the oils were monitored
at regular intervals. The color, PV (0.6–20.7 meq O2/kg, FFA value (0.08–2.1%), tocopherol content (360–1700 ppm%), oryzanol content (460–2,000 mg%), and sesame oil antioxidants
(400–2,000 mg%) were not changed in either the starting oils or their blends. Oils and oil blends containing a higher initial
PV (18.9–20.7 meq O2/kg) showed a slight reduction in value at 40°C, whereas oils having lesser PV of 5–10 showed a slight increase during the
storage period. Among the minor components studied, only β-carotene showed a reduction, 8.9–60.2% at 27°C and 48–71% at 40°C,
for the different oil blends studied. The observed results indicated that the packed oil blends studied were stable under
the conditions of the study, and the minor components, other than β-carotene, remained unaltered in the package even at the
end of 6 mon of storage. 相似文献
4.
Kornkanok Aryusuk Jiraporn Puengtham Supathra Lilitchan Narumon Jeyashoke Kanit Krisnangkura 《Journal of the American Oil Chemists' Society》2008,85(5):475-479
The effects of minor components in crude rice bran oil (RBO) including free fatty acids (FFA), rice bran wax (RBW), γ-oryzanol,
and long-chain fatty alcohols (LCFA), on alkali refining losses were determined. Refined palm oil (PO), soybean oil (SBO)
and sunflower oil (SFO) were used as oil models to which minor component present in RBO were added. Refining losses of all
model oils were linearly related to the amount of FFA incorporated. At 6.8% FFA, the refining losses of all the model oils
were between 13.16 and 13.42%. When <1.0% of LCFA, RBW and γ-oryzanol were added to the model oils (with 6.8% FFA), the refining
losses were approximately the same, however, with higher amounts of LCFA greatly increased refining losses. At 3% LCFA, the
refining losses of all the model oils were as high as 69.43–78.75%, whereas the losses of oils containing 3% RBW and γ-oryzanol
were 33.46–45.01% and 17.82–20.45%, respectively. 相似文献
5.
High-oryzanol rice brain oil (HORBO), rice bran oil (RBO), and partially hydrogenated soybean oil (PHSBO) were used to prepare
french fries. Polar fractions of the three oils were analyzed for nonvolatile components by high-performance size-exclusion
chromatography (HPSEC) with ELSD. In all frying experiments, both HORBO and RBO yielded predominantly dimeric and monomeric
materials. The concentrations of polymeric species in HORBO and RBO were greater than in PHSBO. The major degradation products
from HORBO, RBO, and PHSBO were dimers (8.93 mg/100 mg oil), monomers (10.5 mg/100 mg oil), and DG (22.4 mg/100 mg oil), respectively.
Thermal degradation via hydrolysis was much greater in PHSBO than in HORBO or RBO. Distribution data indicated that the extent of polymer formation
from frying was in the order RBO>HORBO >PHSBO, consistent with the degree of lipid unsaturation and the oryzanol content in
these oils. HPSEC-ELSD results from the two RBO showed that the amounts of various polymeric species, including trimers and
higher polymers, were lower in HORBO than in RBO. The percentage of polar materials and the percentage of polymerized TG,
which were used as indicators of oil quality and stability, decreased with increasing tocopherol and oryzanol contents in
the order PHSBO>HORBO>RBO. 相似文献
6.
Optimization of Physical Refining to Produce Rice Bran Oil with Light Color and High Oryzanol Content 总被引:1,自引:0,他引:1
Vera Van Hoed Jose Vila Ayala Marta Czarnowska Wim De Greyt Roland Verhé 《Journal of the American Oil Chemists' Society》2010,87(10):1227-1234
Crude rice bran oil (RBO) is rich in valuable minor components such as tocotrienols, phytosterols and γ-oryzanol. These compounds
are well preserved during physical refining, but in current industrial practice, RBO is mostly refined chemically because
this results in a lighter color. However this process removes most of the γ-oryzanol. The challenge is to develop a refining
process which combines a high γ-oryzanol retention with the commercially desired light color. A modified physical refining
process was developed, consisting of an acid degumming, prebleaching, dewaxing, physical removal of free fatty acids using
packed column technology, a modified washing step, conventional bleaching and deodorization. A RBO with acceptable oryzanol
retention of 39% had a Lovibond red color value (measured with a 5.25-inch cell) of 2.8, approaching very close the color
of a chemically refined RBO (red = 2). At the process step where high (94%) retention of γ-oryzanol was achieved, a somewhat
darker Lovibond red value of 5.2 was obtained. 相似文献
7.
A novel process for physically refining rice bran oil through simultaneous degumming and dewaxing 总被引:1,自引:0,他引:1
A new process for the physical refining of rice bran oil through combined degumming and dewaxing was developed on a laboratory
scale and then demonstrated on a commercial scale. The simultaneous degumming and dewaxing of the crude oil with a solution
of water and CaCl2, followed by crystallization at a low temperature (20°C), facilitated precipitation of the hydratable and nonhydratable phosphatides
along with the wax, which enabled its separation and reduction to a greater extent. Bleaching and subsequent winterization
(20°C) of this oil further reduced the phosphorus content to less than 5 ppm. Thus, these pretreatment steps enabled the physically
refined rice bran oil to meet commercially acceptable levels for color, FFA content, and cloud point values (10–12 Lovibond
units in a 1-in, cell, <0.25%, and 4–5°C, respectively) with very low neutral oil loss; this has not been observed hitherto.
Rice bran oil is known for its high levels of bioactive phytochemicals, such as oryzanol, tocols, and sterols. The process
reported here could retain more than 80% of these micronutrients in the end product.
This paper was previously presented at the 95th AOCS Annual Meeting and Expo, Cincinnati, Ohio, May 9–12, 2004 相似文献
8.
Autocatalytic esterification of free fatty acids (FFA) in rice bran oil (RBO) containing high FFA (9.5 to 35.0% w/w) was examined
at a high temperature (210°C) and under low pressure (10 mm Hg). The study was conducted to determine the effectiveness of
monoglyceride in esterifying the FFA of RBO. The study showed that monoglycerides can reduce the FFA level of degummed, dewaxed,
and bleached RBO to an acceptable level (0.5±0.10 to 3.5±0.19% w/w) depending on the FFA content of the crude oil. This allows
RBO to be alkali refined, bleached, and deodorized or simply deodorized after monoglyceride treatment to obtain a good quality
oil. The color of the refined oil is dependent upon the color of the crude oil used. 相似文献
9.
F. Dionisi J. Prodolliet E. Tagliaferri 《Journal of the American Oil Chemists' Society》1995,72(12):1505-1511
A method involving reversed-phase high-performance liquid chromatography with amperometric detection has been developed for
the analysis of tocopherols and tocotrienols in vegetable oils. The sample preparation avoids saponification. Recoveries of
α-tocotrienol and γ-tocotrienol in extra virgin olive oil were 97.0 and 102.0%, respectively. No tocotrienols were detected
in olive, hazelnut, sunflower, and soybean oils, whether virgin or refined. However, relatively high levels of tocotrienols
were found in palm and grapeseed oils. This method could detect small quantities (1–2%) of palm and grapeseed oils in olive
oil or in any tocotrienol-free vegetable oil and might, therefore, help assess authenticity of vegetable oils. 相似文献
10.
D. Bodger J. B. Davis D. Farmery T. W. Hammonds A. J. Harper R. V. Harris L. Hebb N. MacFarlane P. Shanks K. Southwell 《Journal of the American Oil Chemists' Society》1982,59(12):523-530
Eleven winged bean accessions from Thailand were analyzed. Oil content ranged between 15 and 18%. Oleic and linoleic acids
were the major fatty acids (62.5–64.5%) together with behenic (12.6–14.4%) and lignoceric acid (2.4–2.8%). Linolenic acid
level was low and traces of 15-, 17- and 21-carbon acids (saturated and unsaturated) were found. No parinaric acid was detected.
Campesterol, stigmasterol and β-sitosterol were the principal components of the unsaponifiable fraction. The extracted oil
had a very low free fatty acid (FFA) content but was not completely liquid below 35 C. The refining of crude winged bean oil
is reported. Oil produced by expeller had a strong, beany aroma but a negligible level of gums and a low level of FFA. Degumming
and neutralizing were unnecessary; bleaching produced an attractive colored oil free from beany aroma. Crude solvent-extracted
oils from whole and decorticated winged beans had appreciable contents of gums and higher FFA contents than expeller-produced
oil. Laboratory refining demonstrated the strong interference on bleaching exerted by gums and FFA. Conventional refining
by degumming, neutralizing, bleaching and deodorizing, and by physical refining produced high-quality oils having a good color,
low FFA level and no taste or smell. The solid/liquid ratio of refined winged bean oil as a function of temperature was found
to be unusual. Oil was extracted from whole and decorticated winged beans in a pilot solvent extraction plant designed to
simulate a Rotocei. Winged bean flakes were not as mechanically strong as those from soybean but good oil extraction yields
were obtained and a meal was produced having an oil content of less than 1% at 10% moisture. Whole winged beans were expelled
in a small expeller (throughput 16.8 kg/hr). Cake was produced with a residual oil content of 3.3–5% in a single pass through
the expeller. 相似文献
11.
Four samples of the unsaponifiables of basking shark liver oil were adsorbed on alumina and eluted to yield Fractions 1–5,
inclusive. Analyses by temperature programmed GC and by silica gel chromatography showed hydrocarbons in the first four fractions
with squalene increasing to Fraction 3 and the pristane level being highest in Fraction 1. Aside from pristane and squalene,
other hydrocarbons occurred at levels of 420–750 mg% in the oils on a weight basis, of which about 60% constituted a series
of n-paraffins (relative carbon number range: 15.0–38.0) together with smaller amounts of at least one branched chain saturated
group. Unsaturated hydrocarbons eluted mainly after squalene. The oils contained up to 460 mg% sterol and 78–270 mg% alcohols
of C10 to C30, the ratio of saturated to unsaturated members being about 1.6. The composition of the unsaponifiable lipids of pig liver
was quite different from that of the marine oils. It contained 10.6% sterol in addition to 400 mg% alcohols, the latter consisting
of 81.8% saturated components (C12 to C31; ratio of saturated: unsaturated members, 4.4). The hydrocarbons comprised 450–700 mg% of the unsaponifiable mixture and
squalene, paraffins and additional unsaturated components occurred at levels of 20.6, 24.4 and 11.9 mg%, respectively. The
saturated hydrocarbons were high in normal homologs of relative carbon number range, 15 to 36; pristane could not be detected. 相似文献
12.
Wai-Lin Siew Yew-Ai Tan Thin-Sue Tang 《Journal of the American Oil Chemists' Society》1994,71(9):1013-1016
The amount of bleaching earth required in the physical refining process of palm oil depends on the activity of the earth,
quality of the oil and final color specification of the refined products. The use of silica (Trisyl) in combination with bleaching
clay in palm oil refining has been investigated. The optimum conditions required for Trisyl and bleaching clay are 95–105°C
for a period of 30–40 min. Improvements in color performance for palm oil products are noted with the addition of small quantities
of Trisyl (0.06–0.24%) to the bleaching clay. Addition of 0.12% Trisyl to 0.4% bleaching clay improved the color of the refined
oil by as much as 1.7 Red Lovibond units. Lower phosphorus levels (18.4 and 16.9 ppm) were obtained in the refined oils with
an addition of 0.12 and 0.24% Trisyl, respectively, as compared to a level of 36.2 ppm of phosphorus when no silica was added
to the earth. Better color stability was also obtained with oils treated with Trisyl. An additional advantage was the reduction
in filtration time, leading to possible higher throughput in refining. 相似文献
13.
Sodeif Azadmard-Damirchi Paresh C. Dutta 《Journal of the American Oil Chemists' Society》2007,84(3):297-304
Free and esterified forms of sterols provide detailed information on the identity and the quality of vegetable oils. In this
study, 4,4′-dimethylsterols in free and esterified forms were investigated in hazelnut and virgin olive oils. Moreover, a
sample of solvent-extracted hazelnut oil was refined at the laboratory to monitor the effects of processing on the levels
of 4,4′-dimethylsterols. Generally, the level of total 4,4′-dimethyslterols was higher in the esterified form (49–68%) compared
with that in free form (32–51%) of these compounds in the hazelnut oil. In virgin olive oil samples, cycloartenol and 24-methylenecycloartanol
were present in higher amounts in free forms (70–80%) than in esterified forms (20–30%). Among the refining processes, degumming,
deodorization, neutralization and bleaching, only neutralization and bleaching considerably reduced 4,4′-dimethylsterols.
In fully refined hazelnut oil, 18 and 37% of lupeol and an unknown compound X in the esterified form were lost, respectively.
The loss of these two compounds in the free form was considerably higher, 26 and 72%, respectively. GC–MS analysis showed
that adulteration of olive oil with a sample of fully refined hazelnut oil could be detected at a level as low as 2% by tracing
lupeol in total or only in esterified forms of 4,4′-dimethylsterols. Further studies on the levels of free and esterified
4,4′-dimethylsterols and their retention during refining processes are anticipated in hazelnut cultivars from different origins. 相似文献
14.
Review on Recent Trends in Rice Bran Oil Processing 总被引:1,自引:0,他引:1
Mahua Ghosh 《Journal of the American Oil Chemists' Society》2007,84(4):315-324
Rice bran oil (RBO) is popular in several countries such as Japan, India, Korea, China and Indonesia as a cooking oil. It
has been shown that RBO is an excellent cooking and salad oil due to its high smoke point and delicate flavor. The nutritional
qualities and health effects of rice bran oil are also established. RBO is rich in unsaponifiable fraction (unsap), which
contains the micronutrients like vitamin E complexes, gamma oryzanol, phytosterols, polyphenols and squalene. However, the
high FFA and acetone-insoluble content of RBO made it difficult for processing. Therefore, in recent years, research interest
has been growing in RBO processing to obtain good quality oil with low refining loss. This review article deals with detailed
reports on RBO processing including membrane-based techniques from the production and quality point of view. 相似文献
15.
A new method for free fatty acid reduction in frying oil using silicate films produced from rice hull ash 总被引:4,自引:0,他引:4
Sodium silicate films were produced from rice hull ash silica, and their application in reducing free fatty acid (FFA) in
frying oil was investigated. Sodium hydroxide concentration of these films was 32, 28, 24, and 20% with silica concentration
of 45, 50, 55, and 60%, respectively. Moisture contents of these films were 20–23%. Adsorption performance of the films was
investigated in frying oil at 80°C for 10–40 min. FFA content gradually decreased with treatment time for all films. There
were no significant differences in FFA content among films for treatments up to 30 min. Treatment with 45 and 50% silica films
for 40 min led to significantly larger reduction in FFA compared to treatment with 60% silica film. Differences between the
FFA content of oil treated for 40 min with 55% silica and the FFA content of oils treated with other silica films were insignificant.
FFA content of oil decreased from 0.8 to 0.55, 0.55, 0.57, and 0.59% after 40 min treatment with 45, 50, 55, and 60% silica
film, respectively. Peroxide values (PV) of treated oils slightly increased from 48 to about 60 meq/kg for films with 45,
50, and 55% silica. Treatment with 60% silica led to a decrease in PV values to 42 meq/kg. Soap content of oil increased from
51 to over 100 ppm as a result of silicate film treatment. 相似文献
16.
Microwave roasting effects on the physico-chemical composition and oxidative stability of sunflower seed oil 总被引:1,自引:0,他引:1
Fozia Anjum Farooq Anwar Amer Jamil M. Iqbal 《Journal of the American Oil Chemists' Society》2006,83(9):777-784
The purpose of the present study was to explore the influences of microwave heating on the composition of sunflower seeds
and to extend our knowledge concerning the changes in oxidative stability, distribution of FA, and contents of tocopherols
of sunflower seed oil. Microwaved sunflower seeds (Helianthus annuus L.) of two varieties, KL-39 and FH-330, were extracted using n-hexane. Roasting decreased the oil content of the seeds significantly (P<0.05). The oilseed residue analysis revealed no changes in the contents of fiber, ash, and protein that were attributable
to the roasting. Analysis of the extracted oils demonstrated a significant increase in FFA, p-anisidine, saponification, conjugated diene, conjugated triene, density, and color values for roasting periods of 10 and
15 min. The iodine values of the oils were remarkably decreased. A significant (P<0.05) decrease in the amounts of tocopherol constituents of the microwaved sunflower oils also was found. However, after
15 min of roasting, the amount of α-tocopherol homologs was still over 76 and 81% of the original levels for the KL-39 and
FH-330 varieties, respectively. In the same time period, the level of σ-tocopherol fell to zero. Regarding the FA composition
of the extracted oils, microwave heating increased oleic acid 16–42% and decreased linoleic acid 17–19%, but palmitic and
stearic acid contents were not affected significantly (P<0.05). 相似文献
17.
B. K. De 《Journal of the American Oil Chemists' Society》2006,83(5):443-448
The purpose of this study was to investigate enzymatic and autocatalytic esterification of FFA in rice bran oil (RBO), palm
oil (PO), and palm kernel oil (PKO), using MG and DG as esterifying agents. The reactions were carried out at low pressure
(4–6 mm Hg) either in the absence of any added catalyst at high temperature (210–230°C) or in the presence of Mucor miehei lipase at low temperature (60°C). The reactions were carried out using different concentrations of MG, and the optimal FFA/MG
ratio and time were 2∶1 (molar) and 6 h, respectively, in both auto- and enzyme-catalyzed processes. With DG as the esterifying
agent in the autocatalytic process, the optimal temperature was 220°C, and the optimal FFA/DG ratio was 1∶1.25. For both MG
and DG, the enzymatic process was more effective in reducing FFA and produced more favorable levels of unsaponifiable matter
and color in the final product. The PV of the final products were also lower (1.8–2.9 mequiv/kg) by using the enzymatic process.
To produce edible-grade oil, a single deodorization step would be required after enzymatic esterification; whereas, alkali
refining, bleaching, and deodorization would be required after autocatalytic treatment. 相似文献
18.
N. Shen W. Fehr L. Johnson P. White 《Journal of the American Oil Chemists' Society》1996,73(10):1327-1336
Lipoxygenase (LOX)-null soybean lines that lack LOX 2, or LOX 2 and 3, and contain normal (8.0–8.6%) or low (2.0–2.8%) linolenate
(18∶3) amounts were evaluated for their oil qualities and storage stabilities. Soybean oils of six genotypes were extracted
by both laboratory-scale and pilot-plant systems and were refined, bleached, and deodorized in the laboratory. Citric acid
was added to oils during the cool-down stage of deodorization. Two replications, separated at the point of conditioning, were
evaluated for each genotype. Under storage conditions of 55–60°C in the dark, soybean oils with low 18∶3 contents were significantly
(P<-0.05) more stable as measured by peroxide values than were oils with normal 18∶3 contents, regardless of the LOX content
of the beans. The volatile analysis showed few differences between oils with low and high 18∶3 contents or among oils from
beans that lack different LOX enzymes. After 16 d of storage, the amount of 1-octen-3-ol was significantly greater in oils
with low 18∶3 content, and soybean oils from beans with normal LOX content had a significantly (P<-0.05) lower amount of 1-octen-3-ol than did the oils that lacked LOX enzymes. Storage at 35°C under light showed no differences
in volatile amounts or sensory evaluations after 14 d of storage. During storage, peroxide values tended to be lower in oils
from beans with normal 18∶3 content and in oils from beans with normal LOX content. Generally, the abscence of LOX 2 or LOX
2 and 3, although having a small effect on lipid oxidation, was not as important to oil quality as was the 18∶3 content. 相似文献
19.
V. Van Hoed G. Depaemelaere J. Vila Ayala P. Santiwattana R. Verhe W. De Greyt 《Journal of the American Oil Chemists' Society》2006,83(4):315-321
The effects of each individual step of the chemical refining process on major and minor components of rice bran oil were examined.
In comparison with common vegetable oils, rice brain oil contains a significantly higher level of several bioactive minor
components such as γ-oryzanol, tocotrienols, and phytosterols. Alkali treatment or neutralization results in a significant
loss of oryzanol. In addition, it gives rise to a change in the individual phytosterol composition. After bleaching, some
isomers of 24-methylenecycloartanol were detected. Because of their relatively high volatility, phytosterols and tocotrienols
are stripped from the rice brain oil during deodorization and concentrated in the deodorizer distillate. At the same time,
oryzanol is not volatile enough to be stripped during deodorization; hence, the oryzanol concentration does not change after
deodorization. Complete refining removed 99.5% of the FFA content. Depending on the applied deodorization conditions, trans FA can be formed, but the total trans content generally remains below 1%. 相似文献
20.
T. Verleyen R. Verhe A. Cano A. Huyghebaert W. De Greyt 《Journal of the American Oil Chemists' Society》2001,78(10):981-984
A rapid and direct Fourier transform infrared (FTIR) spectroscopic method using a 25-μm NaCl transmission cell was developed
for the determination of free fatty acids (FFA) in six important vegetable oils (corn, soybean, sunflower, palm, palm kernel,
and coconut oils) that differ in fatty acid profile. The calibrations were established by adding either standard FFA (oleic,
lauric acids) or a representative mixture of FFA obtained after saponification of the refined oils. For all oils, up to a
FFA level of 6.5% for coconut oil, the best correlation coefficient was obtained by linear regression of the free carboxyl
absorption at 1711 cm−1. All correlation coefficients were greater than 0.993, and no significant difference between the calibration methods could
be detected. Upon validation of the calibration, no significant difference (α=0.05) between the “actual” and the “FTIR predicted”
FFA values could be observed. The calibration models developed for the six oils differed significantly and indicate the need
to develop a calibration that is specific for each oil. In terms of repeatability and accuracy, the FTIR method developed
was excellent. Because of its simplicity, quick analysis time of less than 2 min, and minimal use of solvents and labor, the
introduction of FTIR spectroscopy into laboratory routine for FFA determination should be considered. 相似文献