bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation and characterization of a Δ‐‐desaturation‐defective mutant of an arachidonic acid‐producing fungus, Mortierella alpina 1S‐4
Authors: Jareonkitmongkol Saeree , Sakuradani Eiji , Shimizu Sakayu
Published: November 2006

A mutant, considered to be defective in Δ9‐desaturation, of an arachidonic acid‐producing fungus, Mortierella alpina 1S‐4, was isolated after treating the wild‐type spores with N‐methyl‐N′‐nitro‐N‐nitrosoguanidine. The mycelial FA of this mutant included 38% stearic acid, the level being only 5% for the wild type. Upon growth at 24–28°C, its mycelial lipids included a high level (up to 50 mol% of total mycelial lipids) of FFA, of which about 90 mol% was stearic acid. However, the level of FFA was markedly decreased with a concomitant increase in the IAG level when the mutant was grown at 20°C or lower, or when it was grown in a culture medium supplemented with PUFA.
A simple capillary column GC method for analysis of palm oil‐based polyol esters
Authors: Yunus Robiah , Lye Ooi Tian , Fakhru'l‐Razi A. , Basri Shahnor
Published: November 2006

A reliable, simultaneous analysis of palm oil polyol esters using capillary column GC is described. The polyol esters were esterified from palm oil methyl esters (POME) and palm kernel oil methyl esters (PKOME) with trimethylolpropane [2‐ethyl‐2‐(hydroxymethyl)‐1,3‐propanediol; TMP] to produce the biodegradable base oil for lubricant production. Analysis was performed using a high‐temperature capillary column, SGE HT5 operated at a temperature gradient of 6°C/min starting from 80 to 340°C. Before injection, the sample was derivatized with N,O‐bis (trimethylsilyl)trifluoroacetamide in ethyl acetate at 40°C for at least 10 min. This procedure provides a complete separation of reaction products: TMP, methyl esters, monoesters (ME), diesters (DE), and triesters (TE). As expected, the ME from palm kernel oil was resolved into five major peaks, DE into seven peaks, and TE into 10 peaks. Since no standard was available for this sample, the identities of the peaks were established by a secondary standard that was derived from pure methyl esters. This GC method has made possible the simultaneous determination of reaction product compositions in order to assess the extent of reaction.
Rapid and simultaneous analysis of 16‐O‐methylcafestol and sterols as markers for assessment of green coffee bean authenticity by on‐line LC‐GC
Authors: Kamm Willibald , Dionisi Fabiola , Fay Laurent‐Bernard , Hischenhuber Claudia , Schmarr Hans‐Georg , Engel Karl‐Heinz
Published: November 2006

An on‐line LC‐GC method for analysis of 16‐O‐methylcafestol (16‐OMC) and total sterols in oils obtained from green beans of Coffea canephora (Robusta) and C. arabica (Arabica) has been developed. HPLC pre‐separation of the transesterified lipids allows quantification of the content of 16‐OMC. The fraction containing the sterols is transferred to on‐line GC analysis. The results obtained for Arabica and Robusta samples were in good agreement with literature data obtained by classical analytical procedures. The method allows rapid and simultaneous determination of two markers (16‐OMC and Δ5‐avenasterol) proposed for authenticity assessment of coffee beans and overcomes time‐consuming sample pretreatment steps.
Partial purification and properties of lipase from germinating seeds of Jatropha curcas L.
Authors: Abigor Roland D. , Uadia Patrick O. , Foglia Thomas A. , Haas Michael J. , Scott Karen , Savary Brett J.
Published: November 2006

Lipase present in the seeds of Jatropha curcas L. was isolated and some of its properties studied. Lipase activity was detected in both dormant and germinating seeds. The lipase was partially purified using a combination of ammonium sulfate precipitation and ultrafiltration, which increased the relative activity of the lipase by 28‐ and 80‐fold, respectively. The lipase hydrolyzed palm kernel, coconut, and olive oils at comparable rates (approximately 5 μg FFA/μg protein/min); palm—Raphia hookeri and Jatropha curcas L.—oils at about twice the rate of the first group of oils; and palm and fish oils at a higher rate than all other oils. The lipase, however, had the highest activity with monoolein. Optimal pH and temperature for maximal lipase activity were 7.5 and 37°C, respectively. The addition of ferric ion (15 mM) to the lipase assay medium caused 90% inhibition of lipase activity, whereas calcium and magnesium ions enhanced lipase activity by 130 and 30%, respectively.
Functional properties of low‐fat soy flour produced by an extrusion‐expelling system
Authors: Heywood A. A. , Myers D. J. , Bailey T. B. , Johnson L. A.
Published: November 2006

Low‐fat soy flour (LFSF) obtained by extrusion‐expelling processing was investigated for functional properties. Flours with the following various levels of protein dispersibility indexes (PDI) and residual oil (RO) contents were investigated: “high” 67±4/10.4±1, “mid” 42±3/7.4±2, and “low” 14±5/6.5±0. The solubility of all three LFSF was minimal at pH 4.0 and increased at more alkaline and acidic pH levels. Water‐holding capacity (WHC) increased with a decrease in PDI and RO content, whereas fat‐binding capacity (FBC) decreased. Foaming stability increased as PDI and RO increased, with significant differences between all LFSF samples. Emulsification capacity (EC) was measured at three pH levels (5.5, 6.7, and 8.0). At each pH level, the “low” samples showed the least EC compared to the “mid” and “high” samples, with no significan difference between the “mid” and “high” samples at pH 6.7 and 8.0. Emulsification stability and activity decreased from low LFSF to high LFSF. This study showed that in general low LFSF was less functional than the other flours tested and there was no significant difference in the functionality of mid‐ and high‐LFSF samples.
Changes in FA composition and antioxidative activity of pigment extracts from Korean red pepper powder (Capsicum annuum L.) Due to processing conditions
Authors: Kim Suna , Park Jaebok , Hwang Kyeong
Published: November 2006

The FA compositions by parts of Korean red pepper (Capsicum annuum L.) were analyzed, and the changes in FA composition and antioxidative activity in pigment extracts due to processing were investigated. The main FA in the pericarp and seeds were palmitic, oleic, and linoleic acids. Linoleic acid in the seeds was 73.9% of the total FA, or about 1.7 times as much as in the pericarp. Linolenic acid was scarcely present in the seeds. The percentages of unsaturated FA in the pericarp and seeds were 73.3 and 83.2, respectively. The ratios among FA varied according to the processing conditions, but the FA compositions themselves remained approximately the same. The antioxidative activity of pigment extracts in the photooxidation of linoleic acid was measured by monitoring oxygen consumption and conjugated diene formation. Changes in drying methods resulted in significant differences in antioxidative activity, but changes in storage conditions had little effect. Conjugated diene formation and oxygen consumption were positively correlated. An improved drying method could allow the antioxidative activity of red pepper pigments to be conserved.
Application of FTIR spectroscopy in determining sesamol in sesame seed oil
Authors: Mirghani M. E. S. , Man Y. B. Che , Jinap S. , Baharin B. S. , Bakar J.
Published: November 2006

A new analytical method was developed for determining sesamol in sesame seed oil by FTIR spectroscopy. Sesamol was also spiked at 0 to 1000 mg/kg in freshly refined, bleached, and deodorized palm olein (RBDPOo) and groundnut (peanut) oil. FTIR spectra were recorded using a transmission (NaCl) cell accessory at room temperature, and the partial least squares regression statistical method was used to derive calibration models for each oil. The standard errors of calibration were 6.07, 5.88, and 4.24 mg/100 g for sesame, RBDPOo, and groundnut oils, with coefficients of determination (R2) of 0.9947, 0.9940, and 0.9662, respectively. The calibration models were validated by the “leave‐one‐out” cross‐validation method, and the R2 of validation, the standard errors of prediction, and SD of the differences for repeatability and accuracy were computed. Our results support the premise that FTIR spectroscopy is an efficient and accurate method for determining minor components such as sesamol in edible oils.
Enzymatic extraction of oil from Gevuina avellana, the chilean hazelnut
Authors: Santamaría R. I. , Soto C. , Zúñiga M. E. , Chamy R. , López‐Munguía A.
Published: November 2006

Chilean hazelnut (Gevuina avellana) oil is highly appreciated in the cosmetic and pharmaceutical industries. Hazelnut oil (oil content calculated on 49% dry basis) is traditionally obtained by pressing, a low‐efficiency process that results in a low‐quality product. In this work, the conventional process was compared with two enzymatic alternatives in which commercial enzymes were used to increase the oil extraction yield: (i) extraction in aqueous medium and (ii) extraction by pressing after an enzymatic treatment. The effect of various parameters on the extraction yield was studied to define the most satisfactory processing conditions. These included reaction time, temperature, enzyme concentration, and, in the aqueous medium extraction process, the water/seed ratio, particle size, and pH. Although pressing is the better alternative, in both processes enzyme treatment improved extraction yields (94 and 98% for aqueous medium extraction and pressing after enzyme treatment, respectively, compared to 52% obtained in the conventional process). Moreover, the quality of the oil obtained is the same as or better than that of oil obtained by the conventional process.
Oil stability index correlated with sensory determination of oxidative stability in canola oil
Authors: Broadbent Cameron J. , Pike Oscar A.
Published: November 2006

The usefulness of the Oil Stability Index (OSI) as an accelerated oxidative stability test for canola oil was studied by correlating the OSI with the induction period as determined by sensory analysis. Canola oil was treated by holding it for differing times (0, 1, 2, 3, 4, and 6 d) at elevated temperature (60°C) in the dark with agitation. The sensory induction period (SIP) was determined by storing the five treatments of oil and the control at 60°C in the dark with agitation and removing aliquots of oil for a nine‐member sensory panel to evaluate over a 9‐d period. The time it took for a treatment to reach an average sensory score of 5 (10‐point scoring scale) was defined as the treatment’s SIP. OSI values were obtained on day 0 using a heating block temperature of 110°C and an air pressure of 6 psi. The relationship between SIP and OSI had a 0.89 coefficient of determination (r2). This relationship may be sufficiently strong to warrant use of the OSI in industry applications but may not be ideal for more precise experimental studies of canola oil shelf life.
Regeneration of used frying oils using adsorption processing
Authors: Miyagi Atsushi , Nakajima Mitsutoshi
Published: November 2006

Our study was carried out to improve the quality of used frying oils and to assess the feasibility of recycling by using an adsorption process. Experiments with used frying oils were conducted with a column method using four adsorbents, silica gel, magnesium oxide, activated clay, and aluminum hydroxide gel. Silica gel offered the most effective overall improvement in the quality of used frying oil of the four adsorbents. Although the limiting adsorption capacity of silica gel, as obtained from the Langmuir model, was 219 mg/g for total polar materials (TPM), the experimental maximal adsorption capacity of silica gel for TPM was 337 mg/g. For commercial application, silica gel used in the process must periodically be reactivated. Reactivated silica gel also was effective to some extent in the adsorption process, although the adsorption capacity decreased by 20–50%.
Effect of fruit stoning on olive oil quality
Authors: Patumi M. , Terenziani S. , Ridolfi M. , Fontanazza Giuseppe
Published: November 2006

Stoning olives has been proposed as an alternative to crushing the whole fruit during the oil extraction process. Seven pairs of oils obtained from stoned and nonstoned olives from five different cultivars were evaluated to determine the effect of the proposed technology on oil quality. The main organoleptic and physicochemical parameters as well as resistance to oxidation showed no obvious influence of stoning on oil quality. Chemometric analysis of the data showed the oils grouped more according to genetics (cultivar) than to technology. Lipoxygenase activity in the paste from whole and stoned olives showed no effect that could be attributed to the technology. Furthermore, the stone did not contribute significantly to increasing the lipoxygenase activity in the olive paste.
Lipid composition in tomato skin supercritical fluid extracts with high lycopene content
Authors: Ruiz del Castillo M. L. , Gómez‐Prieto M. S. , Herraiz M. , Santa‐María G.
Published: November 2006

The use of supercritical fluid extraction is proposed for obtaining stable extracts with high added value from natural and economical sources. Lipid composition, namely, of FFA, TAG, and FAME, in tomato skin extracts with high lycopene content was determined. Separation of different classes of lipids was achieved from tomato extracts using TLC followed by transesterification and GC, and lycopene and other carotenoids were analyzed by HPLC with a photodiode array detector. In lycopene extracts obtained using supercritical fluids, no FFA were found and polyunsatureted TAG represented only 9.2% of the total TAG content.
Frying quality and stability of low‐and ultra‐low‐linolenic acid soybean oils
Authors: Warner K. , Gupta Monoj
Published: November 2006

To determine effects of very low levels of linolenic acid on frying stabilities of soybean oils, tests were conducted with 2% (low) linolenic acid soybean oil (LLSBO) and 0.8% (ultra‐low) linolenic acid soybean oil (ULLSBO) in comparison with cottonseed oil (CSO). Potato chips were fried in the oils for a total of 25 h of oil use. No significant differences were found for either total polar compounds or FFA between samples of LLSBO and ULLSBO; however, CSO had significantly higher percentage of polar compounds and FFA than the soybean oils at all sampling times. Flavor evaluations of fresh and aged (1, 3, 5, and 7 wk at 25°C) potato chips showed some differences between potato chips fried in different oil types. Sensory panel judges reported that potato chips fried in ULLSBO and aged for 3 or 7 wk at 25°C had significantly lower intensities of fishy flavor than did potato chips fried in LLSBO with the same conditions. Potato chips fried in ULLSBO that had been used for 5 h and then aged 7 wk at 25°C had significantly better quality than did potato chips fried 5 h in LLSBO and aged under the same conditions. Hexanal was significantly higher in the 5‐h LLSBO sample than in potato chips fried 5 h in ULLSBO. The decrease in linolenic acid from 2 to 0.8% in the oils improved flavor quality and oxidative stability of some of the potato chip samples.
Preparation of alkenyl succinic anhydrides from vegetable oil FAME
Authors: Quesada Joaquín , Morard Marie , Vaca‐García Carlos , Borredon Elisabeth
Published: November 2006

Sunflower oil and oleic motif‐enriched sunflower oil methyl esters were used to prepare alkenyl succinic anhydrides. A classic batch reactor was selected to carry out the synthesis. The range in which the temperature, reaction time, and molar ratio between the number of moles of maleic anhydride and the equivalent number of double bonds present in the unsaturated vegetable oil methyl esters (the most influential factors in the process) varied was determined in a preliminary study. A secondorder Doehlert uniform network design was used to investigate the influence of the temperature and molar ratio for all the methyl esters on the yield of alkenyl succinic anhydride from methyl oleate, the conversion of methyl oleate, the formation of side reaction products, the Gardner color of the product, and viscosity. The optimal reaction conditions for obtaining the maximal yield (around 95%) of alkenyl succinic anhydride from methyl oleate were 235°C, a molar ratio of 1.5, and a reaction lasting 8 h. However, the products synthesized under these conditions showed high viscosity (215 cP), a very dark color (18+ Gardner color), and a high content of undesirable side products (4%), which hindered their direct industrial use. The increase in the product viscosity was probably due to the formation of side reaction products. A molar ratio of less than 1.5 led to a less viscous product, although with a lower alkenyl succinic anhydride content.
Soybean lecithin fractionation and functionality
Authors: Wu Yingzi , Wang Tong
Published: November 2006

Soybean lecithin contains primarity PC, PE, and PI. Fractionation of these phospholipids (PL) is desirable for certain applications. Ethanol was used to fractionate PC and PI, which have different solubilities in this solvent. Various concentrations of ethanol (90, 95, and 100%) and ethanol/gum ratios (0.5, 1.0, 1.5, 2.0, and 2.5) were used. Ethanol concentration significantly influenced the yield of the PC‐enriched fraction and the PC and PI fractionation: The highest ethanol concentration resulted in the highest yield of PC fraction, the most PC in the PC fraction, and the most PI in the PI fraction. The ethanol/gum ratio significantly affected the yield of PC‐enriched fraction, but did not affect the relative PL composition of the PC‐enriched fraction. Ethanol of 90% concentration with a solvent/gum ratio of 3 was used for further large‐scale fractionation. Such fractionation resulted in a PC‐enriched fraction containing 73% PC, 24% PE, and 3% PI based on the total PL content, whereas the PI fraction contained 26% PC, 35% PE, and 39% PI. Functional properties of these two purified fractions, i.e., surface tension reduction, emulsion stability, and oxidative stability, were investigated. The PI‐enriched fraction had a much lower critical micelle concentration than the PC‐enriched fraction, which suggests the PI‐enriched fraction has a higher surface tension reduction capability. For the emulsion stability test, the PI‐enriched fraction performed better than the PC fraction in both water‐in‐oil and oil‐in‐water emulsions. An oxidative stability test showed that these PL were very stable to lipid oxidation.
Selectivity of potato tuber lipid acyl hydrolase toward long‐chain unsaturated FA in esterification reactions with glycerol analogs in organic media
Authors: Pinsirodom Praphan , Parkin Kirk L.
Published: November 2006

FA selectivity of a Celite‐immobilized potato lipid acyl hydrolase (LAH) in esterification reactions with long‐chain FA, including stearic acid (18∶0), oleic acid (18∶1), linoleic acid (18∶2), α‐linolenic acid (18∶3), EPA (20∶5), and DHA (22∶6), and alcohol co‐substrates (n‐propanol, isopropanol, 1,3‐propanediol, and glycerol) was studied in isooctane. Immobilized LAH was selective for FA of greater degrees of unsaturation (18∶3>18∶2>18∶1>18∶0) for all alcohol acceptors evaluated. Selectivity of LAH toward unsaturated C18 FA increased with an increase in water activity (aw) from 0.19 to 0.90 for n‐propanol, isopropanol, and 1,3‐propanediol as alcohol co‐substrates. In contrast, with glycerol as the alcohol cosubstrate, selectivity of LAH toward these unsaturated C18 FA increased with a decrease in aw from 0.90 to 0.19. In addition, immobilized LAH strongly discriminated against EPA and DHA for both 1,3‐propanediol and glycerol as alcohol co‐substrates.
Reactive extraction of acylglycerides usingAspergillus flavusresting cells
Authors: Torres Mercè , Loscos Vicent , Sanahuja Ventura , Canela Ramon
Published: November 2006

A one‐pot TAG extraction and FAME formation using fungal resting cells and oilseeds at moderate temperature are described. The final yield of methyl esters is increased by the sequential addition of water and methanol. The process can be carried out either with solvents or in a solvent‐free system. When a solvent‐free medium is used, the final yield will increase if soft oilseeds are used.
Aqueous extraction, composition, and functional properties of rice bran emulsion
Authors: Monsoor Mamun A. , Proctor Andrew , Howard Luke R.
Published: November 2006

The effect of temperature (20–60°C) on the aqueous extraction of emulsified rice bran oil from commercial rice bran was described. The total solids, protein, fat, and carbohydrate contents of the rice bran emulsions extracted at various temperatures were 4.82–6.99, 1.05–1.40, 0.82–1.65, and 2.65–3.36%, respectively. The mean droplet sizes of the rice bran emulsions extracted at 20, 30, 40, 50, and 60°C were 4.35, 2.92, 3.04, 4.40, and 3.73 μm, respectively. The phenolics extracted at various temperatures ranged from 63.28 to 82.51 mg/100 mL emulsion. The antioxidant capacity (oxygen radical absorbance capacity, ORAC) of rice bran emulsions extracted at various temperatures ranged from 2087 to 3505 μmol Trolox® equivalents per 100 mL of emulsion. The relationship between ORAC and the total phenolic content was highly significant (R2=0.87). The shear stress and apparent viscosity of rice bran emulsions in response to shear strain were similar to those of homogenized whole milk. Hence, the composition and functional properties show the potential of aqueous rice bran extracts as food‐grade emulsions.
A study on the crystal structure of palm oil‐based whipping cream
Authors: Che Man Y. B. , Shamsi K. , Yusoff M. S. A. , Jinap S.
Published: November 2006

The crystal structure of palm oil‐based whipping cream was studied. Various proportions of refined, bleached, and deodorized palm oil (RBDPO) and palm kernel oil (RBDPKO) were prepared and their crystal structure and thermal profile were observed by an X‐ray diffractometer and a differential scanning calorimeter, respectively. The results showed that all blends possessed a stable and shiny β′ polymorph at 25°C, which showed that RBDPO and RBDPKO were appropriate for producing a nondairy whipping cream. Some eutectic effect was observed in some blends, which was attributed to the complex combination of TAG in RBDPO and RBDPKO.
Organogelation of plant oils and hydrocarbons by long‐chain saturated FA, fatty alcohols, wax esters, and dicarboxylic acids
Authors: Daniel Jaiyanth , Rajasekharan Ram
Published: November 2006

Conversion of oils into gels generally involves altering the chemical characteristics of the liquid. We describe here the gelling of vegetable oils, essential oils, and hydrocarbons at ambient temperature, without changing the chemical characteristics of the liquids, using saturated FA having carbon chain lengths of 10 to 31. The gelling ability of the added FA increased linearly with their chain lengths. Structure‐function studies demonstrated that the carboxyl group, position of an additional hydroxyl group, and acyl chain length played an important role in gelation. Long‐chain saturated fatty alcohols, wax esters, and dicarboxylic acids also had the ability to gel plant oils and hydrocarbons.
Effects of alkylamines and PC on the oxidative stability of soybean oil TAG in milk casein emulsions
Authors: Hirose Atsushi , Sato Norifumi , Miyashita Kazuo
Published: November 2006

The effects of alkylamines and PC on the coppercatalyzed oxidation of soybean oil TAG were studied in milk casein emulsions. Stearylamine showed an antioxidant effect in casein emulsions in the presence of PC, whereas dicetylphosphate acted as a prooxidant. The antioxidant or prooxidant effect could be explained by the electrostatic repulsion or attraction between positively charged stearylamine or negatively charged dicetylphosophate and positively charged copper ion at the interface, respectively. On the other hand, these effects were not observed in the absence of PC, suggesting the importance of PC for charged components to show their activities at the interface. Other types of alkylamines—spermine, spermidine, and putrescine—also inhibited the oxidation of soybean oil TAG emulsified with casein in the presence of PC. The antioxidant effects of these natural polyamines were higher than that of stearylamine. PC molecular species also affected soybean oil TAG oxidation in emulsion. The oxidative stability of soybean oil TAG increased in the emulsion with PC containing oleic acid.
Antioxidant activity of extracts of defatted seeds of niger (Guizotia abyssinica)
Authors: Shahidi Fereidoon , Desilva Cyril , Amarowicz Ryszard
Published: November 2006

Niger (Guizotia abyssinica) seed was ground and then defatted with hexane. The meal remaining after oil extraction was tested as a source of antioxidants. Three solvent systems, A [80∶20 (vol/vol) ethanol/water], B [80∶20 (vol/vol) acetone/water], and C (water) were evaluated as extraction media. Crude extracts were examined for their antioxidant activity in a β‐carotene‐linoleate and a meat model system. Extract A exhibited superior antioxidant activity, compared to extracts B and C, and its composition was studied further by using column chromatography and HPLC. Four fractions (I–IV) were obtained, of which fractions III and IV showed activity in the β‐carotene‐linoleate model system. Fraction IV was also highly effective in scavenging the 2,2‐diphenyl‐1‐picrylhydrazyl radical but was less active when used in a bulk oil model system. Preparative TLC showed fraction IV as consisting of two components. UV spectroscopy suggested that the major active component pressent was a chlorogenic acid‐related compound. Furthermore, HPLC analysis established that chlorogenic acid was dominant in the free phenolics fraction (2.6 mg/g). Upon hydrolysis, however, a substantial amount of caffeic acid (42.8 mg/g) was released, presumably from esterified and glycosylated chlorogenic acid. Thus, niger extracts derive their antioxidant activity, at least in part, from the chlorogenic acid‐related compounds.
Functional properties of soy protein fractions produced using a pilot plant‐scale process
Authors: Bian Yilin , Myers Deland J. , Dias Kalyani , Lihono Makuba A. , Wu Shaowen , Murphy Patricia A.
Published: November 2006

Soy proteins fractionated by the modified Nagano process (Nagano method) and a simplified pilot‐plant process (CCUR method) were studied for their functional properties, including solubility, viscosity, emulsification, and foaming. The functional properties of the three fractions produced by the Nagano method—glycinin (11S), β‐conglycinin (7S), and an intermediate fraction (IM)—were studied under a selected range of pH, ionic strengths, and protein concentrations. The 11S fraction was more soluble than the 7S at pH 2–3, whereas the 7S was more soluble than 11S at pH 5–6. Adding NaCl changed the solubility of both fractions at pH 4–5 compared to a neutral pH. Other functional properties were related to solubility in the 7S and 11S fractions. The CCUR method yielded only two fractions, 11S and 7S, and the functionality of those fractions was tested at a neutral pH. The solubility of the CCUR samples was slightly higher at extreme pH levels compared to 11S and 7S fractions from the Nagano method at a neutral pH. The relationship between solubility and other functional properties was clearer in CCUR samples. These results indicate that the simplified pilot‐scale CCUR fractionation process can influence the functional properties of the protein fractions.
Functional properties of the acidic and basic subunits of the glycinin (11S) soy protein fraction
Authors: Dias Kalyani , Myers Deland J. , Bian Yilin , Lihono Makuba A. , Wu Shaowen , Murphy Patricia A.
Published: November 2006

The functional properties of low‐ and high‐M.W. (LMW and HMW, respectively) acidic subunits and the basic subunit separated from the 11S soy protein fraction were studied and compared with the functional properties of the 11S fraction. Among the functional properties investigated were solubility, emulsification, and viscosity. The results showed that the LMW acidic subunit had higher solubility than the HMW acidic subunit. Among all the samples, the LMW subunit separated by using β‐mercaptoethanol (ME) was the most soluble, with a solubility of 98–100% at a pH of 6–12. The solubility profile of the HMW subunit followed a pattern similar to the solubility of 11S. The lowest solubility was observed around pH values in the range close to the isoelectric point for both the LMW and HMW subunit. The basic subunit was not soluble in the pH range 3–10; however, the solubility increased more than 50% at pH 13 compared to the solubility at pH 10. The emulsification capacity of all subunits was higher than 11S in the following descending order: LMW, basic, HMW, 11S. Emulsification activity and stability of the subunits were greater than those of the 11S samples at room temperature and 95°C. With the exception of the LMW subunit separated with ME, the subunits had a higher viscosity than 11S. The basic subunit separated with sodium bisulfite had the highest viscosity of all the samples tested.
Oxidation, flavor, and texture of walnuts reduced in fat content by supercritical carbon dioxide
Authors: Crowe Tammy D. , White Pamela J.
Published: November 2006

English walnuts are popular because of their good taste, high n−3 FA content, and reported hypocholesterolemic effects. However, walnuts have a high fat content (∼70% w/w) that is highly polyunsaturated, which contributes to oxidative instability. The objectives of this study were: (i) to use supercritical carbon dioxide (SC‐CO2) extraction to decrease the total fat content of walnuts, and (ii) to determine the effects of SC‐CO2 lipid extraction on the oxidative stability, flavor, and textural characteristics of the reduced‐fat walnuts. The fat content of English walnut pieces was reduced by 25 and 40% with a pilot‐scale SC‐CO2 extraction system. Full‐fat, 25‐, and 40%‐reduced‐fat walnuts were stored at 25 and 40°C for 8 wk. FA profiles were similar for residual oil in all treatments, and the profiles did not change with storage. PV and volatile compounds were significantly greater (P<0.05) in full‐fat walnuts than in reduced‐fat walnuts at both storage temperatures. A trained sensory panel judged the reduced‐fat walnuts to be less astringent and to have less walnut and rancid flavors. Full‐fat walnuts had greater hardness than reduced‐fat walnuts by both sensory and instrumental texture profile analyses. In general, reducing the relative fat contents of walnuts by 25% improved oxidative stability and maintained a high level of consumer acceptance.
New metal catalysts for soybean oil transesterification
Authors: Abreu Frederique R. , Lima Daniela G. , Hamú Elias H. , Einloft Sandra , Rubim Joel C. , Suarez Paulo A. Z.
Published: November 2006

We report here the synthesis, characterization, and use of tin (3‐hydroxy‐2‐methyl‐4‐pyrone)2(H2O)2, lead (3‐hydroxy‐2‐methyl‐4‐pyrone)2 (H2O)2, mercury (3‐hydroxy‐2‐methyl‐4‐pyrone)2‐(H2O)2, and zinc (3‐hydroxy‐2‐methyl‐4‐pyrone)2(H2O)2 as catalysts in the transesterification reaction of soybean oil with methanol. All complexes are active in this reaction, with the following decreasing activities: Sn2+≫Zn2+>Pb2+≈Hg2+. The catalytic activities of these complexes were also compared with classical alkali and acid transesterification catalysis (with NaOH and H2SO4).
Rheological properties of emulsions containing modified soy protein isolates
Authors: Puppo M. C. , Sorgentini D. A. , Añón M. C.
Published: November 2006

The feasibility of replacing common emulsifiers with soy protein isolates (SPI) in low‐calorie salad dressings was evaluated. Structural modifications of SPI were obtained by thermal‐acidic treatment with or without neutralization (TH1.6N and TH1.6, respectively). Modification of flow properties of TH1.6 and TH1.6N emulsions by thermal treatment and different protein concentrations was evaluated through shear stress vs. shear rate measurements in a rotational viscometer. TH1.6N isolates generated emulsions with higher shear stress and apparent viscosity than those prepared with TH1.6. Heated TH1.6N emulsions at 10% protein gave the highest values of shear stress and plastic flow behavior. These emulsions had high consistency, viscosity, and elasticity. TH1.6N isolates had lower emulsifying capacity than TH1.6, probably due to the higher protein aggregation produced during neutralization, which prevented protein unfolding. These isolates would be suitable for the preparation of stable emulsions with adequate consistency and elasticity.
A new method for determining gossypol in cottonseed oil by FTIR spectroscopy
Authors: Mirghani M. E. S. , Che Man Y. B.
Published: November 2006

A new method was developed to determine the gossypol content in cottonseed oil using FTIR spectroscopy with a NaCl transmission cell. The wavelengths used were selected by spiking clean cottonseed oil to gossypol concentrations of 0–5% and noting the regions of maximal absorbance. Transmittance values from the wavelength regions 3600–2520 and 1900–800 cm−1 and a partial least squares (PLS) method were used to derive FTIR spectroscopic calibration models for crude cottonseed, semirefined cottonseed, and gossypol‐spiked cottonseed oils. The coefficients of determination (R2) for the models were computed by comparing the results from the FTIR spectroscopy against those obtained by AOCS method Ba 8‐78. The R2 were 0.9511, 0.9116, and 0.9363 for crude cottonseed, semirefined cottonseed, and gossypol‐spiked cottonseed oils, respectively. The SE of calibration were 0.042, 0.009, and 0.060, respectively. The calibration models were cross‐validated within the same set of oil samples. The SD of the difference for repeatability and accuracy of the FTIR method were better than those for the chemical method. With its speed (ca. 2 min) and ease of data manipulation, FTIR spectroscopy is a useful alternative to standard wet chemical methods for rapid and routine determination of gossypol in process and/or quality control for cottonseed oil.
Fat‐soluble vitamin extraction by analytical supercritical carbon dioxide
Authors: Perretti Giuseppe , Marconi Ombretta , Montanari Luigi , Fantozzi Paolo
Published: November 2006

Extraction of fat‐soluble vitamins (A, D, E, and β‐carotene) by supercritical carbon dioxide (SC‐CO2) was tested to replace conventional liquid extraction methods, which require large volumes of organic solvents. Supercritical fluid extraction (SFE) is a rapid extraction technique for fat‐soluble vitamins enabling them to be accurately determined using only small volumes of organic solvents. Extractions were performed on ultra‐high‐temperature sterilized milk, milk powder, pork, liver pâté (pâté de fois), infant formula, and canned baby food to compare the methods. The proposed method is based on the extraction of fat‐soluble vitamins and their esters by using SC‐CO2 with methanol as a modifier. HPLC analysis using photometric detection was used for the vitamin analysis. The results showed no significant differences between extraction methods. The proposed SFF method appears to be useful as a substitute for the traditional organic solvent method, mainly for vitamin A and γ‐tocopherol.
Parameter optimization for the enzymatic hydrolysis of sunflower oil in high‐pressure reactors
Authors: Primožič Mateja , Habulin Maja , Knez Željko
Published: November 2006

This study is concerned with the hydrolysis of sunflower oil in the presence of lipase preparation Lipolase 100T (Aspergillus niger lipase). Supercritical carbon dioxide was used as a solvent for this reaction. In a high‐pressure stirred tank reactor operated in a batch mode, the effects of various process parameters (temperature, pressure, enzyme/substrate ratio, pH, and oil/buffer ratio) were investigated to determine the optimal reaction rate and conversion for the hydrolysis process. The optimal concentration of lipase was 0.0714 g/mL of CO2‐free reaction mixture, and the highest conversions of oleic acid (0.193 g/g of oil phase) and linoleic acid (0.586 g/g of oil phase) were obtained at 50°C, 200 bar, pH=7, and an oil/buffer ratio of 1∶1 (w/w).
Characterization of side‐chain oxidation products of sitosterol and campesterol by chromatographic and spectroscopic methods
Authors: Johnsson Lars , Dutta Paresh C.
Published: November 2006

Based on the cholesterol‐lowering effects of phytosterols, known since the 1950s, extra phytosterol amounts have been added to certain food products for almost 10 yr. Literature reports on oxidation of phytosterols in general are limited, and data on side‐chain oxidation of these compounds are scarce. The aim of this study was to investigate and characterize autoxidation products from a mixture of the two phytosterols sitosterol and campesterol. A commercial mixture of the two sterols was oxidized for 72 h at 120°C in an air‐ventilated oven. The oxidation products were separated by preparative TLC and identified and characterized with GC‐MS. The following oxidation products were identified from the two phytosterols: 24‐methylcholest‐5‐en‐3β,24‐diol, 24‐methylcholest‐5‐en‐3β,25‐diol, 24‐methylcholest‐4‐en‐6α‐ol‐3‐one, 24‐methylcholest‐4‐en‐6β‐ol‐3‐one, 24‐ethylcholest‐5‐en‐3β,24‐diol, 24‐ethylcholest‐5‐en‐3β, 25‐diol, 24‐ethylcholest‐4‐en‐6α‐ol‐3‐one, 24‐ethylcholest‐4‐en‐6β‐ol‐3‐one. Full‐scan mass spectra of these compounds are reported for the first time as their trimethylsilyl‐ether derivatives.
Thermodynamic properties of the enzymatic hydrolysis of sunflower oil in high‐pressure reactors
Authors: Primožič Mateja , Habulin Maja , Knez Željko
Published: November 2006

On the basis of our previous results, where optimal conditions for the lipase‐catalyzed hydrolysis of sunflower oil in a high‐pressure batch stirred tank reactor were determined, some thermodynamic and kinetic properties of lipase preparation Lipolase 100T (Aspergillus niger lipase) were established. Activation energy (32.7 kJ/mol) was determined from an Arrhenius plot. Activity of the Lipolase 100T increased between 35 and 50°C, but with further temperature increase thermal deactivation occurred. The thermal deactivation rate constant was 0.40, and the deactivation enthalpy was 123.0 kJ/mol. Because of the desirability of continuous applications of enzyme‐catalyzed reactions, a high‐pressure continuous flat‐shape membrane reactor (HP CFSMR) was designed. Hydrolysis of sunflower oil in this reactor was performed. Maximal conversion in the HP CFSMR was achieved after 1 h. A polysulfone membrane was successfully used as a separation unit, and the highest conversion of FFA was determined at 50°C, 200 bar, and a flow rate for substrates of 0.1 mL/min (each).
Thraustochytrid as a potential source of carotenoids
Authors: Aki Tsunehiro , Hachida Kazutaka , Yoshinaga Megumi , Katai Yuko , Yamasaki Takashi , Kawamoto Seiji , Kakizono Toshihide , Maoka Takashi , Shigeta Seiko , Suzuki Osamu , Ono Kazuhisa
Published: November 2006

Thraustochytrids, marine protists whose dominant genera are Thraustochytrium and Schizochytrium, belong to the kingdom Chromista and are known as an industrial source of DHA. We describe here that thraustochytrid strain KH105, isolated as a DHA producer, also accumulates significant levels of β‐carotene and xanthophylls including canthaxanthin and astaxanthin. A4‐d cultivation using a medium composed of 10% glucose and less than 0.3% of nitrogen sources in a half‐concentration of seawater gave an astaxanthin production up to 6.1 mg/L, and canthaxanthin content reached more than 10 mg/L under conditions where a higher concentration of nitrogen sources (6%) was employed. It might be advantageous in mass production systems for these carotenoids to be extracted readily by simply suspending the cells with organic solvents such as acetone and chloroform. Analyses on the morphological and life history features of the KH105 strain revealed that it belongs to the genus Schizochytrium. This particular species of thraustochytrids is thus considered to be a promising source of xanthophylls as well as DHA for use in the food industry.
Total fat analysis in milk‐ and soy‐based infant formula powder by supercritical fluid extraction
Authors: Wolf Wayne R. , LaCroix Denis E. , Goel Ritu , Kaur Manpreet
Published: November 2006

A rapid method for the determination of total fat in infant formula powders using a commercially available supercritical fluid extraction (SFE) instrument was evaluated. The matrices examined were Standard Reference Material SRM 1846 Infant Formula (NIST) and commercial milk‐ and soybased infant formula powders. Method verification and validation were done by linear regression analysis using the Method of Standard Additions. A Data Quality Objectives (DQO) format was used to define and evaluate the performance characteristic parameters of the instrumental total fat analysis fy SFE. A peer validation study showed excellent agreement with the declared labeled percentage fat values and reproducibility among three participating laboratories. The laboratory relative SD (RSDR %) is within Horwitz's limits of acceptability and the HORRAT ratio criteria at the level of the analyte analyzed. Linear regression analysis of all infant formula matrices spiked with added fat showed that the SFE instrument response was due only to the added analyte. By integrating the DQO process with a readily available certified reference material, along with reproducibility indicated by two outside collaborating laboratories, we established verification and validation of the accuracy of the data obtained by SFE.
Membrane and additional adsorption processes for quality improvement of used frying oils
Authors: Miyagi Atsushi , Subramanian Rangaswamy , Nakajima Mitsutoshi
Published: November 2006

The main focus of our study was to improve the quality of used frying oils for recycling as edible oils. Experiments were conducted with hexane‐diluted, used frying oils in a batch membrane cell using a nonporous polymeric composite membrane for improving permeate (oil) flux. The oil flux increased by 9‐ to 14‐fold as compared to the permeate flux obtained with undiluted oil. Furthermore, the quality of processed oils was comparable with membrane‐processed, undiluted oil. The maximal oil flux was obtained when the weight ratio of oil to oil‐hexane retentate (feed) was 0.47 in the process stream. Examination of successive fractions of permeate revealed that membrane performance was not affected by variation in the feed quality. Although the membrane process improved the overall quality of used frying oil, it was not effective in reducing FFA and oxidation products. By combining membrane and adsorption processes, the quality of the used frying oil could be improved to the level of fresh frying oil. Silica gel along with a small amount of magnesium oxide gave the best results in the adsorption process. Combined membrane and adsorption processes seem to be the appropriate approach for the complete regeneration of used frying oils.
Influence of heat and refining on formation of CLA isomers in sunflower oil
Authors: Juanéda Pierre , de la Pérrière Stéphanie Brac , Sébédio Jean‐Louis , Grégoire Stéphane
Published: November 2006

The aims of this study were to determine whether CLA are formed during refining of vegetable oils and to study the level and composition of CLA during heating. The effects of three refining steps (neutralization, bleaching, and deodorization) were analyzed with respect to their effect on CLA content. Two temperatures (180 and 220°C) were used for heating; CLA appeared only after deodorization. The level of CLA was positively influenced by temperature. More CLA were present after treatment at 220°C than at 180°C (1.3 and 0.2% of total FA, respectively). The high temperature modified the relative proportions of the CLA isomers. The main CLA isomers in fresh or heated oils were the trans,trans ones (mainly 9,11 and 10,12 isomers).
FA and tocopherol composition of Vietnamese oilseeds
Authors: Matthaus Bertrand , Vosmann Klaus , Pham Long Quoc , Aitzetmüller Kurt
Published: November 2006

Seeds of 40 oilseed species from 23 different plant families (Brassicaceae, Cucurbitaceae, Fabaceae, Sapindaceae, Malvaceae, Gnetaceae, Clusiaceae, Bruseraceae, Ranunculaceae, Convolvulaceae, Amaranthaceae, Tiliaceae, Basellaceae, Solanaceae, Umbelliferae, Labiatae, Compositae, Theaceae, Euphorbiaceae, Caesalpiniaceae, Sapotaceae, Anacardiaceae, and Connaraceae) grown in Vietnam were analyzed for oilseed oil content, FA, and vitamin E. The seed oil content varied between 0.2 g/100 g for Mangifera indica and 75.7 g/100 g for Calophyllum inophyllum, whereas only nine seeds contained more than 40% oil. The tocopherol content ranged from 26 (Sapindus mukorossi) to 9361 mg/kg (Litchi chinensis). In nine seed oils unusual FA such as conjugated, cyclopropenoic, or epoxy FA were found.
Kinetics of the catalytic esterification of castor oil with lauric acid using n‐butyl benzene as a water entrainer
Authors: Kulkarni Mangesh G. , Sawant Sudhirprakash B.
Published: November 2006

The esterification of castor oil with lauric acid was investigated using tetra n‐butyl titanate (TBT), SnCl2·2H2O (stannous chloride), CoCl2·6H2O (cobalt chloride), and (CH3COO)2Zn·2H2O (zinc acetate dihydrate) as catalysts. Effects of catalyst concentration and reaction temperature on the progress of the reaction were investigated. TBT was the best catalyst for the esterification of castor oil with lauric acid at temperatures lower than 200°C. The reaction was first order with respect to each reactant. The activation energy for the esterification reaction of castor oil with lauric acid using TBT was 26.69 kcal/mol. The rate constants obtained for the esterification of castor oil with decanoic, lauric, palmitic, and stearic acids were nearly the same (15.80, 15.44, 15.06, and 14.67 mL mol−1 min−1), as were the rate constants obtained for the reaction of castor oil and hydrogenated castor oil.
Blending of hydrogenated low‐erucic acid rapeseed oil, low‐erucic acid rapeseed oil, and hydrogenated palm oil or palm oil in the preparation of shortenings
Authors: Danthine Sabine
Published: November 2006

Two ternary systems of fats were studied. In the first system, low‐erucic acid rapeseed oil (LERO), hydrogenated lowerucic acid rapeseed oil (HLERO), and palm oil (PO) were blended. In the second system, hydrogenated palm oil (HPO) was used instead of PO and was blended with LERO and HLERO. The blends were then studied for their physical properties such as solid fat content (SFC), melting curves by DSC, and polymorphism (X‐ray). HPO showed the highest melting enthalpy after 48 h at 15°C (141±1 J/g), followed by HLERO (131±2 J/g), PO (110±2 J/g), and LERO (65±4 J/g). Binary phase behavior diagrams were constructed from the DSC and X‐ray results. Iso‐line diagrams of partial‐melting enthalpies were constructed from the DSC results, and binary and ternary isosolid diagrams were constructed from the NMR results. The isosolid diagrams demonstrated formation of a eutectic along the binary blend of PO/HLERO. However, no eutectic effect was observed along the binary lines of HPO/HLERO, PO/LERO, HPO/LERO, or HLERO/LERO. The same results were found with the iso‐line diagrams of partial‐melting enthalpies. As expected, addition of PO or HPO increased polymorphic stability in the β′ form of the HLERO/LERO mixture.