Characterization of Lipase-Catalyzed Structured Lipids from Selected Vegetable Oils with Conjugated Linoleic Acid: Their Oxidative Stability with Rosemary Extracts

Response surface methodology was used to optimize the lipase‐catalyzed transesterification reaction between conjugated linoleic acid (CLA) and soybean oil. On the basis of the model, structured lipids (SLs) were synthesized from CLA and soybean oil or sunflower oil. CLA was incorporated in SL‐soybean (24.4 mol%) and SL‐sunflower (23.1 mol%), respectively. Isomerization to trans, trans CLA was observed during the reaction. Throughout the oxidation study, all SLs showed higher peroxide values (POVs), p‐anisidine values, and 2‐thiobarbituric acid‐reactive substance values than their counterparts. Rosemary extracts with a different amount (100 to 300 ppm) could effectively reduce oxidation in soybean oil, sunflower oil, and their SLs.     

共轭亚油酸氧化稳定性及其抗氧化性的研究

对由红花籽油制取的共轭亚油酸(CLA)和红花籽油组成脂肪酸(SFA)进行氧化稳定性比较。过氧化值和硫代巴比妥酸反应物的测定结果表明，在实验条件下，CLA的氧化稳定性高于SFA，但CLA并不是一种抗氧化剂。米糠油对于CLA的抗氧化效果与BHT相似。     

Effect of safflower oil, flaxseed oil, monensin, and vitamin E on concentration of conjugated linoleic acid in bovine milk fat

Conjugated linoleic acid (CLA) refers to a mixture of conjugated octadecadienoic acids of predominantly ruminant origin. The main isomer in bovine milk fat is the cis-9, trans-11 CLA. Interest in CLA increased after the discovery of its health-promoting properties, including potent anticarcinogenic activity. Two experiments were conducted to evaluate dietary strategies aimed at increasing the concentration of CLA in bovine milk fat. Both experiments were organized as a randomized complete block design with a repeated measures treatment structure. In Experiment 1, 28 Holstein cows received either a control diet or one of 3 treatments for a period of 2 wk. The control diet consisted of 60% forage (barley silage, alfalfa silage, and alfalfa hay) and 40% concentrate on a dry matter (DM) basis, fed as a total mixed ration (TMR). The concentrate was partially replaced in the treatment groups with 24 ppm of monensin (MON), 6% of DM safflower oil (SAFF), or 6% of DM safflower oil plus 24 ppm of monensin (SAFF/M). Average cis-9, trans-11 CLA levels in milk fat after 2 wk of feeding were 0.45, 0.52, 3.36, and 5.15% of total fatty acids for control, MON, SAFF, and SAFF/M, respectively. In Experiment 2, 62 Holstein cows received either a control diet or one of 5 treatment diets for a period of 9 wk. The control diet consisted of 60% forage (barley silage, alfalfa silage, and alfalfa hay) and 40% concentrate on a DM basis, fed as a TMR. The concentrate was partially replaced in the treatment groups with 6% of DM safflower oil (SAFF), 6% of DM safflower oil plus 150 IU of vitamin E/kg of DM (SAFF/E), 6% of DM safflower oil plus 24 ppm of monensin (SAFF/M), 6% of DM safflower oil plus 24 ppm of monensin plus 150 IU of vitamin E/kg of DM (SAFF/ME), or 6% of DM flaxseed oil plus 150 IU of vitamin E/kg of DM (FLAX/E). Average cis-9, trans-11 CLA levels during the treatment period were 0.68, 4.12, 3.48, 4.55, 4.75, and 2.80% of total fatty acids for control, SAFF, SAFF/E, SAFF/M, SAFF/ME, and FLAX/E, respectively. The combination of safflower oil with monensin was particularly effective at increasing milk fat CLA. The addition of vitamin E to the diet partially prevented the depression in milk fat associated with oilseed feeding, but had no significant effect on the concentration of CLA in milk.     

响应面优化红花籽油碱异构化法制备共轭亚油酸的研究

以新疆优质红花籽油为原料,通过碱异构化法制备共轭亚油酸(CLA)。采用单因素试验研究了异构化过程中反应温度、反应时间、PEG-400用量、Fe(OH)_3用量对CLA转化率的影响,同时采用响应面法对制备工艺进行优化。结果表明:在红花籽油质量为20 g前提下,红花籽油碱异构化法制备共轭亚油酸的最佳工艺条件为以PEG-400为溶剂、Fe(OH)_3为催化剂、反应温度178℃、反应时间2.7 h、PEG-400用量265 m L、Fe(OH)_3用量6 g,在此条件下,CLA转化率为96.54%。     

Effects of short-term administration of conjugated linoleic acid on lipid metabolism in white and brown adipose tissues of starved/refed Otsuka Long-Evans Tokushima Fatty rats

The present study explored the short-term effects of dietary conjugated linoleic acid (CLA) on body fat accumulation and lipid metabolism in starved/refed Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Male OLETF rats of 12-weeks-old were starved for 24 h and then re-fed for 48 h either with CLA diet [7.5% CLA and 7.5% safflower oil (SAF)] or SAF control diet (15% SAF oil). The results demonstrated a 27% reduction of white adipose tissue wet weight (total of epididymal and perirenal adipose tissue weight) in the CLA group compared to the control group. The activity of mitochondrial carnitine palmitoyltransferase (CPT), the rate-limiting enzyme for fatty acid oxidation, was significantly elevated by 1.7- and 1.6-fold in perirenal white adipose tissue and interscapular brown adipose tissues, respectively, in the CLA group compared to the control. In contrast, phosphatidate phosphohydrolase (PAP), the rate-limiting enzyme for triglyceride (TG) synthesis, was found to be 23 and 15% lower, in perirenal white- and brown- adipose tissue of CLA-fed rats, respectively. In addition, CLA feeding led to a significant reduced concentration of serum total- and HDL-cholesterol and phospholipid. Thus, dietary CLA evidently lowers abdominal white adipose tissue wet weight through an enhanced fatty acid oxidation and a reduced TG synthesis.     

Supercritical electrocatalytic catalyst activation and its application in safflower seed oil isomerisation to prepare conjugated linoleic acid

The supported Ru/Na-ZSM-5 catalyst was prepared by loading Ru on the zeolite support by the impregnation method. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis showed that Ru was successfully supported. The supported catalyst was subjected to supercritical electrocatalytic activation, and the activated catalyst was applied to the isomerisation of safflower seed oil. The effect of activation conditions on the conjugated linoleic acid (CLA) yield was examined. Under the supercritical CO₂ condition, the optimal activation conditions were electrocatalytic current of 200 mA, reaction temperature of 70 °C, stirring speed of 300 r.p.m and reaction time of 1.5 h. The CLA yield was 43.10%, the content of c9,t11-CLA in the product oil was 17.45% and the content of t10,c12-CLA was 15.86%, significantly higher than the raw oil. The change was not noticeable in terms of physicochemical properties compared with the raw oil, which met edible vegetable oil quality standards.     

Catalyst activation by cold plasma technology and its effect on isomerization of safflower seed oil

High voltage atmospheric cold plasma (HVACP) is a novel catalyst modification technology. In this study, a ruthenium/multi-walled carbon nanotubes (Ru/MWCNTs) catalyst was activated by HVACP instead of the thermal reduction method. The results showed that HVACP activation under the conditions of 180 s discharge time, 150 W discharge power, and 2.5 cm electrode spacing at 25 °C could effectively decrease the activation temperature and time. At this time, the Ru dispersion was 20.1% and the conjugated linoleic acid (CLA) yield was 43.0%. Catalyst characterization proved that the HVACP-treated catalyst did not aggregate and had a good activation effect. The catalyst was applied to the isomerization reaction of safflower seed oil to obtain CLA-rich safflower seed oil. The total CLA content was 43.02%, the trans-oleic acid content was 1.34%, the iodine value (IV) was 133.50 gI₂/100 g, and after reusing five times, the relative activity of the catalyst remained at 77%, which provided the conditions for the preparation of functional oil.     

Volatile oxidation compounds in a conjugated linoleic acid-rich oil

In this study, volatile oxidation compounds formed in a commercial conjugated linoleic acid (CLA)-rich oil were quantified and results compared to those found in safflower oil (rich in linoleic acid, LA). Intact oil samples and pure triacylglycerols obtained following elimination of tocopherols and minor compounds were oxidised at 60 °C, and volatile oxidation compounds were analysed by solid phase microextraction-gas chromatography with flame ionisation detector and mass spectrometer. Results showed that while, as expected, hexanal was the major volatile oxidation compound found in oil and triacylglycerols rich in LA, both hexanal and heptanal equally were the most abundant compounds in oil and triacylglycerols rich in CLA. Besides, samples rich in CLA also showed significantly high quantities of trans-2-octenal and trans-2-nonenal and the latter, along with heptanal, were absent in samples rich in LA. Results for CLA samples were not easy to interpret since major volatiles found are not expected from theoretically stable hydroperoxides formed in CLA and could in part derive from dioxetanes coming from 1,2-cycloadditions of CLA with oxygen. Overall, results obtained support evidence that oxidation mechanisms of CLA may differ than those of LA. Also, it was concluded that heptanal determination could serve as a useful marker of oxidation progress in CLA-rich oils.     

Biocatalyzed acidolysis of olive oil triacylglycerols with 9c,11t and 10t,12c isomers of conjugated linoleic acid

Lipase catalyzed acidolysis of triacylglycerols (TAG) of olive oil with 9c,11t and 10t,12c isomers of conjugated linoleic acid (CLA) in an organic solvent was studied. The CLA isomers were first obtained in good yield starting from sunflower oil. The acidolysis reactions were carried out with two immobilized lipase, an sn-1,3-regiospecific one from Rhizomucor miehei and a nonregiospecific one from Candida antartica, in order to valuate not only the total incorporation of CLA isomers in olive TAG but also the distribution of the cited isomers in the three sn positions of TAG molecules. The effect of reaction time was also investigated; in fact two series of reactions, with the two lipases, were carried out for 24, 48 and 72 h. The TAG fractions relative to the starting olive oil TAG (OOTAG) and to the samples obtained from the acidolysis reactions were analyzed to obtain the total and positional fatty acid percentage compositions. The results show that after 24 h of reaction, high levels of CLA isomers were incorporated in OOTAG using Lipozyme IM and that slightly higher values were obtained by increasing the reaction time; Novozym 435 was less effective in catalyzing the incorporation of CLA isomers and CLA isomers were incorporated in OOTAG to a lesser degree. The results of stereospecific analysis of TAG fractions showed that, at every reaction time, the CLA isomers were incorporated mainly in sn-1 and sn-3 positions, as expected on the basis of the enzyme regiospecificity. As regards the TAG sn-2 position, the incorporation of CLA isomers was not observed after 24 h, but after 48 and 72 h; this occurrence was probably due to isomerization phenomena or regiospecificity loss after extended reaction times.     

Effectiveness of rosemary essential oil as an inhibitor of lipid and protein oxidation: Contradictory effects in different types of frankfurters

The effect of increasing levels (150, 300 and 600ppm) of rosemary essential oil on lipid and protein oxidation and the increase of non-heme iron (NHI) content during refrigeration (+4°C/60 days) of frankfurters produced with tissues from Iberian pigs (IF) or white pigs (WF), was studied. Frankfurters with no added essential oil were used as controls. Iberian pigs were free-range reared and fed on acorns and pasture whereas white pigs (Large-white×Landrance) were intensively reared and fed on a mixed diet. Large differences were detected between types of frankfurters (Iberian vs white) in terms of fatty acid composition and tocopherols content due to the different feeding background of the animals. The effect of the addition of rosemary essential oil on the oxidative stability of frankfurters depended on the level of added essential oil and the characteristic of the frankfurter. The rosemary essential oil successfully inhibited the development of lipid and protein oxidation in IF with that antioxidant effect being more intense at higher concentrations of essential oil. In WF, 150ppm rosemary essential oil showed an antioxidant effect, significantly reducing the generation of lipid and protein oxidation products. At higher levels (300 and 600ppm) the essential oil had, in general, no effect on lipid oxidation while significantly enhanced the oxidation of proteins and the release of iron from myoglobin. The presence of certain amounts of tocopherols in the frankfurters could have influenced the activity displayed by the added essential oil leading to antioxidant or prooxidants effects though the different fatty acid composition and oxidative status between frankfurters could also have had an effect.     

Studies of reaction variables for lipase-catalyzed production of alpha-linolenic acid enriched structured lipid and oxidative stability with antioxidants

Alpha-linolenic acid (ALA) enriched structured lipid (SL) was produced by lipase-catalyzed interesterification from perilla oil (PO) and corn oil (CO). The effects of different reaction conditions (substrate molar ratio [PO/CO 1:1 to 1:3], reaction time [0 to 24 h], and reaction temperature [55 to 65 °C]) were studied. Lipozyme RM IM from Rhizomucor miehei was used as biocatalyst. We obtained 32.39% of ALA in SL obtained under the optimized conditions (molar ratio-1:1 [PO:CO], temperature-60 °C, reaction time-15 h). In SL, the major triacylglycerol (TAG) species (linolenoyl-linolenoyl-linolenoyl glycerol [LnLnLn], linolenoyl-linolenoyl-linoleoyl glycerol [LnLnL]) mainly from PO and linoleoyl-linoleoyl-oleoyl glycerol (LLO), linoleoyl-oleoyl-oleoyl glycerol (LOO), palmitoyl-linoleoyl-oleoyl glycerol (PLO) from CO decreased while linolenoyl-linolenoyl-oleoyl glycerol (LnLnO) (18.41%), trilinolein (LLL) (9.06%), LLO (16.66%), palmitoyl-linoleoyl-linoleoyl glycerol (PLL) (9.69%) were increased compared to that of physical blend. Total tocopherol content (28.01 mg/100 g), saponification value (SV) (192.2), and iodine value (IV) (161.9) were obtained. Furthermore, oxidative stability of the SL was also investigated by addition of 3 different antioxidants (each 200 ppm of rosemary extract [SL-ROS], BHT [SL-BHT], catechin [SL-CAT]) was added into SL and stored in 60 °C oven for 30 d. 2-Thiobabituric acid-reactive substances (TBARS) value was 0.16 mg/kg in SL-CAT and 0.18 mg/kg in SL-ROS as compared with 0.22 mg/kg in control (SL) after oxidation. The lowest peroxide value (POV, 200.9 meq/kg) and longest induction time (29.88 h) was also observed in SL-CAT.     

Effect of maternal supplementation with essential fatty acids and conjugated linoleic acid on metabolic and endocrine development in neonatal calves

We tested the hypothesis that the maternal supply of essential fatty acids (EFA), especially α-linolenic acid, and conjugated linoleic acid (CLA), affects glucose metabolism, the endocrine regulation of energy metabolism and growth, and the intestinal development of neonatal calves. We studied calves from dams that received an abomasal infusion of 76 g/d coconut oil (CTRL; n = 9), 78 g/d linseed oil and 4 g/d safflower oil (EFA; n = 9), 38 g/d Lutalin (BASF SE) containing 27% cis-9,trans-11 and trans-10,cis-12 CLA (CLA; n = 9), or a combination of EFA and CLA (EFA+CLA; n = 11) during the last 63 d of gestation and early lactation. Calves received colostrum and transition milk from their own dam for the first 5 d of life. Insulin-like growth factor (IGF)-I, leptin, and adiponectin concentrations were measured in milk. Blood samples were taken before first colostrum intake, 24 h after birth, and from d 3 to 5 of life before morning feeding to measure metabolic and endocrine traits in plasma. On d 3 of life, energy expenditure was evaluated by a bolus injection of NaH¹³CO₃ and determination of CO₂ appearance rate. On d 4, additional blood samples were taken to evaluate glucose first-pass uptake and ¹³CO₂ enrichment after [¹³C₆]-glucose feeding and intravenous [6,6-²H₂]-glucose bolus injection, as well as postprandial changes in glucose, nonesterified fatty acids (NEFA), insulin, and glucagon. On d 5, calves were killed 2 h after feeding and samples of small intestinal mucosa were taken for histomorphometric measurements. The concentrations of IGF-I, adiponectin, and leptin in milk decreased during early lactation in all groups, and the concentrations of leptin in first colostrum was higher in EFA than in CTRL cows. Plasma glucose concentration before first colostrum intake was higher in EFA calves than in non-EFA calves and was lower in CLA calves than in non-CLA calves. Plasma IGF-I concentration was higher on d 1 before colostrum intake in EFA calves than in EFA+CLA calves and indicated an overall CLA effect, with lower plasma IGF-I in CLA than in non-CLA calves. Postprandial NEFA concentration was lowest in EFA and CLA calves. The postprandial rise in plasma insulin was higher in EFA than in non-EFA calves. Plasma adiponectin concentration increased from d 1 to d 2 in all groups and was higher on d 3 in CLA than in non-CLA calves. Plasma leptin concentration was higher on d 4 and 5 in EFA than in non-EFA calves. Maternal fatty acid treatment did not affect energy expenditure and first-pass glucose uptake, but glucose uptake on d 4 was faster in EFA than in non-EFA calves. Crypt depth was lower, and the ratio of villus height to crypt depth was higher in the ilea of CLA than non-CLA calves. Elevated plasma glucose and IGF-I in EFA calves immediately after birth may indicate an improved energetic status in calves when dams are supplemented with EFA. Maternal EFA and CLA supplementation influenced postprandial metabolic changes and affected factors related to the neonatal insulin response.     

Protein Oxidation in Frankfurters with Increasing Levels of Added Rosemary Essential Oil: Effect on Color and Texture Deterioration

The development of protein oxidation as assessed by the total carbonyl content and its influence on color and texture deterioration during the refrigerated storage (+4 °C/60 d) of frankfurters, were studied. The effect of the addition of a rosemary essential oil at different levels (150, 300, and 600 ppm) on the protein oxidative stability of the frankfurters was also evaluated. Frankfurters with no added essential oil were used as controls. The amount of carbonyls from protein oxidation significantly increased during refrigerated storage, and this increase was significantly higher in control frankfurters than in those treated with 300 and 600 ppm. Rosemary essential oil at levels of 300 and 600 ppm successfully protected the heme molecule from degradation and significantly inhibited the increase of nonheme iron (NHI) in refrigerated stored frankfurters. Color changes were directly related to oxidation processes because frankfurters with added antioxidants (300 and 600 ppm) suffered less color modifications than the controls. The addition of rosemary essential oil enhanced texture characteristics of frankfurters by reducing hardness, adhesiveness, gumminess, chewiness, and controlling the lost of elasticity during refrigeration. Statistically significant correlations were calculated between protein oxidation and instrumentally measured parameters, suggesting that the alteration of protein functionality caused by oxidation likely affected color and texture characteristics of frankfurters.     

Lipase catalyzed modification of fish oil to incorporate capric acid

Immobilized lipase, IM60, from Rhizomucor miehei, was used as a biocatalyst for the incorporation of capric acid (C10:0) into menhaden fish oil concentrate containing 34.7 mol% eicosapentaenoic acid (20:5n-3) and 34.4 mol% docosahexaenoic acid (22:6n-3). Transesterification (acidolysis) was performed in hexane and solvent-free media. Tocopherol content was analyzed before and after enzymatic modification. Products were analyzed by gas liquid chromatography. After 24 h incubation in hexane, there was an average of 31.1±4.6 mol% incorporation of C10:0 into fish oil, while 20:5 and 22:6 were reduced to 12.6±3.1 and 13.7±4.4, respectively. The solvent-free reaction produced an average of 28.8±4.7 mol% capric acid incorporation; 20:5 and 22:6 decreased to 16.1±5.7 and 13.5±3.0 mol%. The effect of incubation time, substrate mole ratio, enzyme load, and added water were also studied. Generally, as enzyme load, mole ratio, and incubation time increased, mol% capric acid incorporation also increased. Time course of reaction indicated that the highest C10:0 incorporation occurred at 72 h, for both the reaction in hexane (33.5 mol%) and the solvent-free reaction (36.0 mol%). The highest C10:0 incorporation for the substrate mole ratio reaction occurred at a mole ratio of 1:8 in hexane (50.7 mol%) and the solvent-free reaction (36.7 mol%). Although the highest C10:0 incorporation (31.8 and 48.6 mol%) occurred at an enzyme load of 15% in hexane and 20% for the solvent-free reaction respectively, the values were not significantly different (P<0.05) after 5% enzyme load. Mol% incorporation of C10:0 declined with increasing amounts of water. At 1% added water, high C10:0 incorporation was achieved for the reaction in hexane (39.3 mol%) and the solvent-free reaction (26.0 mol%). Pancreatic lipase catalyzed sn-2 positional analysis was performed on the fish oil before and after enzymatic modification. Fish oil containing capric acid was successfully produced and may be beneficial in certain food and nutritional applications.     

酶法合成共轭亚油酸单甘酯的研究

采用脂肪酶G50(来源于Penicillium camembertii)作为生物催化剂,催化共轭亚油酸(CLA)和甘油酯化生成共轭亚油酸单甘酯(MAG)。研究了在无溶剂体系中,底物摩尔比、酶加量、体系含水量、反应温度和反应时间对产物中MAG含量和CLA酯化率的影响。结果表明,最佳反应条件为:底物摩尔比n(甘油)∶n(CLA)=4∶1,加酶量300U/g(基于反应底物总质量),体系含水量1%,反应温度15℃,反应时间24h。在最佳反应条件下,CLA的酯化率达到84.98%,MAG的含量为68.40%,共轭亚油酸双甘酯(DAG)含量为16.58%。通过分析产物的脂肪酸组成,发现Penicillium脂肪酶G50对CLA异构体没有拆分效果。     

无溶剂体系酶法催化酸解合成共轭亚油酸甘油酯

采用商业化固定化酶Novozym 435作为生物催化剂,催化共轭亚油酸(CLA)和葵花籽油的酸解反应合成富含CLA的结构脂质(CLA-SL).研究了在无溶剂体系中,底物摩尔比、酶用量、体系含水量、反应温度和反应时间对产物中CLA含量和Sn-2位CLA含量的影响.结果表明,最佳反应条件为:CLA与葵花籽油摩尔比3 :1,酶用量10%,体系含水量1%,反应温度55 ℃,反应时间36 h.在最佳反应条件下,产物中的CLA含量和Sn-2位CLA含量分别为15.7%和2.73%.     

Physicochemical and Volatile Characterization of Structured Lipids from Olive Oil Produced in a Stirred-tank Batch Reactor

ABSTRACT: Structured lipid (SL) from conjugated linoleic acid (CLA) with olive oil was produced, and the physicochemical and volatile characterizations were investigated. In SL-olive oil, 21.8 mol% of CLA isomers were incorporated, and the removal of tocopherols (63% loss from original olive oil) and chlorophylls (50% loss) was observed. The distinct exothermal peaks observed became broader, and the position of the peak shifted to a lower temperature in SL-olive oil compared with normal olive oil. Reverse-phase (ODS column) high-performance liquid chromatography with an evaporative light-scattering detection separated the newly synthesized SL-triacylglycerols (TAGs), in which the incorporation of CLA into olive oil increased the content of TAGs with partition number <48 from 9% (in olive oil) to 78% (SL-olive oil). Total amount of volatile compounds in SL-olive oil was smaller than those in olive oil, indicating removal of flavor compounds from olive oil occurred during the processes.     

Prooxidant Activity of Oxidized α-Tocopherol in Vegetable Oils

ABSTRACT:  The effect of oxidized α-tocopherol on the oxidative stabilities of soybean, corn, safflower, and olive oils and the oxidation of oleic, linoleic, and linolenic acids were studied. The 0, 650, 1300, and 2600 ppm oxidized α-tocopherol were added to soybean, corn, safflower, and olive oils and 10000 ppm oxidized α-tocopherol to the mixture of oleic, linoleic, and linolenic acids. Samples in the gas-tight vials were stored in the dark for 6 or 35 d at 55 °C. The oxidative stabilities of oils were determined by headspace oxygen with GC and peroxide value. Fatty acids were determined by GC. As the concentration of oxidized α-tocopherol in soybean, corn, safflower, and olive oils increased, the depletion of headspace oxygen and the peroxide values of oils increased during storage. The prooxidant effects of oxidized α-tocopherol on soybean and corn oils with about 55% linoleic acid were greater than those on safflower and olive oils with about 12% linoleic acid, respectively ( P  < 0.05). The changes of fatty acids during storage showed that the oxidation ratios of oleic, linoleic, and linolenic acids were 1 : 2 : 3, 1 : 12 : 26, and 1 : 8 : 16 after 5, 30, and 35 d of storage, respectively. The oxidation of α-tocopherol in oil should be prevented and the oxidized α-tocopherol should be removed to improve the oxidative stability of oils.     

Pilot-scale production of conjugated linoleic acid-rich soy oil by photoirradiation

ABSTRACT:  Conjugated linoleic acid (CLA) is found naturally in dairy and beef products at levels of 0.2% to 2% of the total fat. A more concentrated source of dietary CLA, low in saturated fat, would be highly desirable to obtain optimum CLA levels of about 3 g/d. We recently reported photoisomerization of soy oil with iodine catalysis to be a simple way of producing CLA in laboratory without high-energy input or expensive enzymes and microorganisms. However, a long irradiation time of 144 h has been a limitation for this technique to be of practical value. The objectives of this study were to build a pilot plant unit to rapidly produce high-CLA soy oil by photoirradiation and optimize the processing parameters to obtain high-CLA soy oil. Degassed oil with dissolved-iodine catalyst was irradiated by UV lamps in an illuminated laminar flow unit (ILFU). The ILFU consists of 2 borosilicate glass plates in a silicone lined stainless steel frame. The static mode of operation yielded 5.7% of total CLA isomers and performed twice as well than the continuous mode with 2.5% of total CLA. Irradiating oil in a static mode with reflective surfaces increased the CLA yields 3-fold to 16.4%. About 22% of total CLA isomers can be rapidly produced from soy oil linoleic acid with 0.35% iodine catalyst in a 0.5-cm-thick oil layer maintained at 48 °C for 12 h. The peroxide value and GC-MS analysis did not identify any volatile compounds characteristic of lipid oxidation. This study is a definitive step toward the commercialization of large-scale production of CLA-rich soy oil.