Anti-Rancidity Effects of Sesame and Rice Bran Oils on Canola Oil During Deep Frying

In this study, the effect of sesame oil (SEO) and rice bran oil (RBO) on the rancidity of canola oil (CAO) during the process of frying potato pieces at 180 °C was investigated. The SEO and RBO were added to the CAO at levels of 3 and 6%. Frying stability of the oil samples during the frying process was measured on the basis of total polar compounds (TPC) content, conjugated diene value (CDV), acid value (AV), and carbonyl value (CV). In general, frying stability of the CAO significantly (P < 0.05) improved in the presence of the SEO and RBO. The positive effect of the SEO on the stability of the CAO was more than that of the RBO. Increasing the amounts of SEO and RBO from 3 to 6% led to decreases in the TPC and AV, and increases in the CDV and CV of the CAO during the frying process. The best frying performance for the CAO was obtained by use of 3% of both SEO and RBO together (CAO/SEO/RBO, 94:3:3 w/w/w).     

Frying Stability of Canola Oil Blended with Palm Olein, Olive, and Corn Oils

The fatty acid composition, peroxide value (PV), acid value (AV), iodine value (IV), total tocopherols (TT) content, and total phenolics (TP) content of canola oil (CAO), palm olein oil (POO), olive oil (OLO), corn oil (COO), and the binary and ternary blends of the CAO with the POO, OLO, and COO were determined. The blends were prepared in the volume ratios of 75:25 (CAO/POO, CAO/OLO, CAO/COO) and 75:15:10 (CAO/POO/OLO, CAO/POO/COO). The CAO and its blends were used to fry potato pieces (7.0 × 0.5 × 0.3 cm) at 180 °C. During the frying process, the total polar compounds (TPC) content, AV, oil/oxidative stability index (OSI), and color index (CI) of the CAO/blends were measured. In general, frying stability of the CAO was significantly (P < 0.05) improved by the blending, and the frying performance of the ternary blends was found to be better than that of the binary blends.     

Frying performance of the hull oil unsaponifiable matter of Pistacia atlantica subsp. mutica

The anti‐rancidity effect of the hull oil unsaponifiable matter (USM, 100 ppm) of Pistacia atlantica subsp. mutica (Bene) on sunflower oil (SFO) during frying at 180 °C was investigated and compared to that of tert‐butylhydroquinone (TBHQ, 100 ppm). The unsaponifiable constituents of the Bene hull oil (BHO) were separated into hydrocarbons (3.7%), carotenes (3.6%), tocopherols and tocotrienols (24.7%), linear and triterpenic alcohols (0.9%), methylsterols (5.7%), sterols (3.2%), triterpenic dialcohols (4.7%), and triterpenic dialcohol methylesters (4.5%), by means of silica gel TLC. The results obtained from the measurements of total polar compounds, conjugated diene value, carbonyl value, and acid value during 32 h of frying showed that the frying stability of SFO improves more in the presence of the USM of BHO than in the presence of TBHQ. Moreover, compared to TBHQ, the USM had a better protective effect on the indigenous tocopherols of SFO during frying.     

Antioxidant Activity of Rambutan (Nephelium lappaceum L.) Peel Extract in Soybean Oil during Storage and Deep Frying

Rambutan (Nephelium lappaceum L.) peel (RBP) is discarded as the main by‐product during processing of the fruit. Increasing attention is now paid to the valorization of RBP for the recovery of valuable compounds. Geraniin, ellagic acid, quercetin, and rutin are the main phenolic compounds found in methanolic RBP extract. Extracted rambutan peel powder (ERPP) is used to evaluate the oxidative stability of soybean oil stored at 4 and 30 °C in the dark and light and deep fried with potatoes at 160 °C. Tert‐butylhydroquinone (100 µg g^?1 oil, TBHQ) serves as positive control. Oil supplemented with ERPP of 1000 µg gallic acid equivalents (GAE) g^?1 of oil shows positive effects on the retardation of the oxidation process during storage in comparison with oil without addition. During deep frying, either ERPP (1000 µg GAE g^?1) or TBHQ retards the lipid oxidation of oil. Levels of thiobarbituric acid reactive substances of potatoes fried in oil fortified with the extract and TBHQ (0.4–0.59 µg g^?1) are much lower than those without the extract (1.31 ± 0.10 µg g^?1) (p < 0.05). Therefore, RBP extract exhibits favorable antioxidant effects and can be used for effectively inhibiting lipid oxidation in oil during storage and deep frying. Practical Applications: An extract from rambutan fruit peel containing phenolic compounds, that is, geraniin, ellagic acid, rutin, and quercetin showed promising results to be used as potential antioxidants in soybean oil during deep frying. Both oxidation of the frying oil as well as the oxidation of the food product, that is, potatoes were inhibited. These results demonstrated that rambutan fruit peel extract can be used as a natural antioxidant in frying oil to replace synthetic antioxidants, that is, TBHQ.     

Hydroperoxide as a Prooxidant in the Oxidative Stability of Soybean Oil

Fifteen milliliters of soybean oil having peroxide value (PV) of 0, 2, 4, 6, 8, or 10 meq/kg oil in a 35 mL serum bottle was sealed air-tight with a Teflon rubber septum and aluminum cap and was stored in a forced-air oven at 50 °C. The oxidative stability of soybean oil was evaluated daily for six days by measuring the headspace oxygen content and volatile compounds in the headspace of a sample bottle by gas chromatography. As the initial PV of the oil increased from 0 to 2, 4, 6, 8 and 10, the headspace oxygen decreased and the volatile compounds increased at p < 0.05. Hydroperoxide accelerated the oxidation of soybean oil. The correlation coefficient (R ²) between the headspace oxygen and the volatile compounds was 0.95. The increase of tertiary butyl hydroquinone (TBHQ) from 0 to 50 ppm for the oil of PV 4 or 8 had a significant effect on the oxidative stability at p < 0.05. The increase from 50 to 100 ppm for the oil of PV 4 or 8 did not significantly increase the stability at p > 0.05. The oxidative stability of PV 8 meq/kg and 50 ppm TBHQ was better than the control with PV 0 and 0 ppm TBHQ at p < 0.05. TBHQ was an effective antioxidant to improve the oxidative stability of soybean oil.     

Improvement of Canola Oil Frying Stability by Bene Kernel Oil’s Unsaponifiable Matter

The anti-rancidity effect of the unsaponifiable matter fraction of bene kernel (UFB) oil on canola oil (CAO) during frying was compared to that of tert-butyl hydroquinone (TBHQ). The UFB was separated into hydrocarbons (12.9%), carotenes (9.6%), tocopherols and tocotrienols (65.8%, mainly γ-tocopherol), linear and triterpenic alcohols (3.8%), methyl sterols (2.8%), sterols (3.0%, mainly β-sitosterol, stigmasterol, Δ⁵-avenasterol, and Δ⁷-avenasterol, respectively), and triterpenic dialcohols (2.2%). The results obtained from the measurements of the total polar compounds, the conjugated diene value, the carbonyl value, and total tocopherols showed that the stability of CAO improves similarly in the presence of UFB or TBHQ, and even more in the presence of UFB in some cases (especially inhibition of oxidized triglyceride monomers and triglyceride dimers). The analysis of polar components showed that the antioxidative additives were more effective to resist the formation of thermo-oxidative than hydrolytic products during the frying of CAO.     

Retardation of rancidity in deep-fried instant noodles (ramyon)

The storage stability of instant fried noodles (ramyon) was determined by accelerated aging at 63 C with organoleptic evaluation of the onset of rancidity. Three methods of extending the shelf-life of ramyon were examined: (a) addition of 200 ppm antioxidant, butylated hydroxyanisole (BHA), t-butylhydroquinone (TBHQ), or a polymeric antioxidant (Poly-A) to the frying (palm) oil; (b) coating the inner surface of the polyethylene package with TBHQ equivalent to 200, 500 and 1000 ppm based on the oil in the ramyon; and (c) addition of a mixture of 200 ppm TBHQ and 200 or 500 ppm disodium ethylene-diaminetetraacetate (EDTA) to the frying oil. When the antioxidants were added to the oil, BHA and Poly-A approximately doubled while TBHQ tripled the shelf-life of ramyon. The mixture of TBHQ (200 ppm) and disodium EDTA (500 ppm) in the frying oil quintupled the shelf-life. The inner surface application of TBHQ (200 ppm) extended shelf-life twice that of an equal amount of TBHQ in the frying oil. Rancid off-flavors developed slowest in noodles with a _w 0.3. Hexanal concentration in ramyon was a good indicator of the development of oxidative rancidity. Organoleptic evaluation showed the flavor of ramyon was objectionable when hexanal concentration reached 3.5 ppm based on the weight of ramyon (as is). The relative effectiveness of antioxidants in preventing off-flavor in ramyon could be determined from the hexanal concentration in stored ramyon. This paper was presented at the AOCS meeting in Philadelphia, Pennsylvania, in May 1985. It is contribution #85-167-J, cooperative investigation among the Agricultural Research Service, U.S. Department of Agriculture, and the departments of Grain Science and Industry and Agricultural Engineering, Kansas Agricultural Experiment Station, Kansas State University.     

Evaluation of the Oxidative Stability of Diacylglycerol-Enriched Soybean Oil and Palm Olein Under Rancimat-Accelerated Oxidation Conditions

The oxidative stability of diacylglycerol (DAG)-enriched soybean oil and palm olein produced by partial hydrolysis using phospholipase A1 (Lecitase Ultra) and molecular distillation was investigated at 110 °C by the Rancimat method with and without addition of synthetic antioxidants. Compared with triacylglycerol oils, the DAG-enriched oils displayed lower oxidative stability due to a higher content of unsaturated fatty acids and a lower level of tocopherols. With the addition (50–200 mg/kg) of tert-butylhydroquinone (TBHQ) or ascorbyl palmitate (AP), the oxidative stability indicated by induction period (IP) of these DAG-enriched oils under the Rancimat conditions was improved. The IP of the diacylglycerol-enriched soybean oil increased from 4.21 ± 0.09 to 12.64 ± 0.42 h when 200 mg/kg of TBHQ was added, whereas the IP of the diacylglycerol-enriched palm olein increased from 5.35 ± 0.21 to 16.24 ± 0.55 h when the same level of AP was added. Addition of TBHQ, alone and in combination with AP resulted in a significant (p ≤ 0.05) increase in oxidative stability of diacylglycerol-enriched soybean oil. AP had a positive synergistic effect when used with TBHQ.     

Ziziphi spinosae Semen Oil Enhance the Oxidative Stability of Soybean Oil under Frying Conditions

The objective of this study is to improve the oxidative stability of soybean oil by using Ziziphi spinosae semen oil (ZSSO). In the present study, the oxidative stability, fatty acid composition, tocopherol, and phenolic changes of soybean oil without additives and soybean oil mixed with 5% ZSSO are evaluated during frying at 180 ℃ for 18 h. Tert-butyl hydroquinone (TBHQ) and vitamin E (VE) as common antioxidants are incorporated into soybean oil for comparison. According to the results of oxidative stability assays of conjugated diene value, thiobarbituric acid value, acid values, and total polar compounds, the incorporation of ZSSO significantly restrain the lipid oxidation of soybean oil. After 18 h of frying, the soybean oil samples with ZSSO has more polyunsaturated fatty acids, tocopherols, and DPPH radical scavenging capacity, and less trans fatty acids, compared with TBHQ and VE. In addition, ZSSO-containing soybean oil maintains a high content of phenols during the frying period, which is correlated with the increase in oxidative stability. Therefore, replacing part of soybean oil with ZSSO can effectively reinforce the performance of soybean oil under frying conditions.     

Effect of TBHQ on quality characteristics of RBD olein during frying

The changes in quality characteristics of refined, bleached and deodorized palm olein (RBD olein) during heating with intermittent frying for 5 hr/day for weight consecutive days in three systems were compared. The systems were (i) RBD olein without antioxidant (system 1); (ii) RBD olein to which 200 ppm of tertiary butylhydroquinone (TBHQ) had been added prior to frying on the first day (system 2), and (iii) RBD olein which had TBHQ added to a level of 200 ppm at the start of each day. The addition of TBHQ reduced the level of polar components and polymers in the oil, decreased the rates of change in iodine value and dielectric constant and decreased the rate of oxidation of C18:2. The reduction in the rates of these undesirable changes was more pronounced when the TBHQ was added to the system on each day of frying than when there was a single addition of TBHQ prior to frying on the first day. The undesirable effect of adding TBHQ was that it darkened the oil.     

Structural Effect of Lignans and Sesamol on Polymerization of Soybean Oil at Frying Temperature

The antipolymerization activity of the lignans including nordihydroguaiaretic acid, (+)-pinoresinol, (−)-secoisolariciresinol, enterodiol, and two sesame lignans (sesamol and sesamin), and four model compounds (4-ethylcatechol, 2-methoxy-4-propylphenol, 4-methyl-2,6-dimethoxyphenol, and piperonyl alcohol) were investigated for soybean oil at frying temperature (180 °C). The heated samples were analyzed by gel-permeation chromatography for polymerized triacylglycerols and by ¹H NMR to monitor the decrease in peak intensities for bisallylic protons and olefinic protons. The heating test results were compared with ability to scavenge the radical 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) to understand the relationship between radical-scavenging ability at room temperature and antipolymerization activity at 180 °C. It was found that the antipolymerization activity of a lignan at frying temperature cannot be predicted solely from the radical-scavenging ability at room temperature. The lignans tested in this research had antipolymerization activity, but it was not as strong as that of 200 ppm tert-butylhydroquinone (TBHQ) with equivalent of phenolic moiety (0.0012 meq/g). At higher concentrations, however, sesamol, nordihydroguaiaretic acid, and (+)-pinoresinol had better antipolymerization activity than the legal limit set for TBHQ (200 ppm, 0.0012 meq/g). Therefore, this research showed that by using an appropriate concentration, these natural antioxidants can replace synthetic antioxidants and provide better antioxidation activity.     

Improving the Frying Performance and Oxidative Stability of Refined Soybean Oil by Tocotrienol‐Rich Unsaponifiable Matters of Kolkhoung (Pistacia khinjuk) Hull Oil

Increasing consumer awareness for all natural products has quickly led to growing research on new resources of potent and profitable natural antioxidants. In this context, for the first time, the Kolkhoung hull oil (KHO) (Pistacia khinjuk)‐unsaponifiable matters (USM) (UHO) (100, 200, and 400 mg kg^?1) were incorporated into refined soybean oil (RSO) and the oxidative stability of prepared oils was measured during 32 hours of frying. Then, the obtained results (oxidative stability) were compared to the samples containing tert‐butyl hydroquinone (TBHQ) (100 mg kg^?1) as a common synthetic antioxidant. According to the results of oxidative stability assays of acid values, conjugated diene values and carbonyl values, and total polar compounds, the incorporation of UHO, particularly at a concentration of 200 mg kg^?1, was more efficient in improving the oxidative stability compared to TBHQ. The tocol content of KHO (2043.4 mg kg^?1) was higher than the reported amounts of other conventional edible oils. Furthermore, by incorporation of UHO into RSO, as compared with TBHQ, a better protection of naturally occurring antioxidants (tocopherols and sterols) was found after adding UHO to RSO. This fact was mainly attributed to the UHO's tocotrienol fraction. Hence, the USM of KHO can be used as a potent antioxidant to improve the oxidative stability of frying oils.     

Formation of 4-Hydroxy-2-(<Emphasis Type="Italic">E</Emphasis>)-Nonenal in a Corn–Soy Oil Blend: a Controlled Heating Study Using a French Fried Potato Model

The formation of 4-hydroxy-2-(E)-nonenal (HNE) in a corn–soy oil blend during frying was investigated. Frozen shoestring potatoes were fried once per hour at 180 °C for 8 h/day over a 4-day period. As a control, oil was also heated under identical conditions, except that no product was fried. HNE was quantified by GC–MS using a stable isotope dilution assay with pentaflurobenzyl hydroxylamine hydrochloride (PFBHA) and trimethylsilyl 2,2,2-trifluoro-n-(trimethylsilyl)acetimidate (BSTFA) derivatization. The HNE concentration in the potato fryers increased throughout the first day of frying. On subsequent days the daily maximum HNE concentration was reached after fresh oil was added and the fryer was brought to the frying temperature. The potato fryer oil reached a maximum concentration of 5.6 ppm during the second day of frying. Similarly, the HNE concentration of the oil in the control fryer increased throughout the first day of heating. On subsequent days the daily maximum HNE concentration varied throughout the experimental period. The control fryers reached a maximum concentration of 6.3 ppm at the end of the second day of heating. Throughout the experimental period there was a tendency for the oil in the control fryer to have a greater concentration of HNE than the oil in the potato fryer. Overall time of the experiment and heating with food versus heating without frying food and their interaction were significant in terms of HNE formation.     

Degradation and Nutritional Quality Changes of Oil During Frying

The changes in regular canola oil as affected by frying temperature were studied. French fries were fried intermittently in canola oil that was heated for 7 h daily over seven consecutive days. Thermo-oxidative alterations of the oil heated at 185 ± 5 or 215 ± 5 °C were measured by total polar components (TPC), anisidine value (AV), color components formation, and changes in fatty acid composition and tocopherols. Results showed that TPC, AV, color and trans fatty acid content increased significantly (P < 0.05) as a function of frying temperature and time. The oil polyunsaturated fatty acids (PUFA) decreased in direct proportion to frying temperature and time. After 7 days of frying, the amount of PUFA was reduced by half and the trans isomers contribution increased 2.5 times during frying at 215 °C. Of the parameters assessed, total polar component and color had the highest correlation, with correlation coefficients of 0.9650 and 0.9302 for frying at 215 and 185 °C, respectively. TPC formation correlated inversely with the reduction of tocopherols.     

Addition of ferulic acid,ethyl ferulate,and feruloylated monoacyl- and diacylglycerols to salad oils and frying oils

To determine antioxidative effects of ferulic acid and esterified ferulic acids, these compounds were added to soybean oils (SBO), which were evaluated for oxidative stability and frying stability. Additives included feruloylated MAG and DAG (FMG/FDG), ferulic acid, ethyl ferulate, and TBHQ. After frying tests with potato chips, oils were analyzed for retention of additives and polar compounds. Chips were evaluated for hexanal and rancid odor. After 15 h frying, 71% of FMG/FDG was retained, whereas 55% of ethyl ferulate was retained. TBHQ and ferulic acid levels were 6% and <1%, respectively. Frying oils with ethyl ferulate or TBHQ produced significantly less polar compounds than SBO with no additives. Chips fried in SBO with TBHQ or ferulic acid had significantly lower amounts of hexanal and significantly less rancid odor after 8 d at 60°C than other samples. Oils were also aged at 60°C, and stability was analyzed by PV, hexanal, and rancid odor. Oils with TBHQ or FMG/FDG had significantly less peroxides and hexanal, and a lower rancid odor intensity than the control. FMG/FDG inhibited deterioration at 60°C, whereas ethyl ferulate inhibited the formation of polar compounds in frying oil. Ferulic acid acted as an antioxidant in aged fried food. TBHQ inhibited oil degradation at both temperatures. Presented at the 94th AOCS Meeting & Expo, Kansas City, MO, May 4–7, 2003.     

Antioxidant Activity of Sesamol in Soybean Oil Under Frying Conditions

Antioxidant activity of sesamol was investigated in soybean oil using a miniaturized frying experiment with potato cubes fried at 180 °C. Oxidation of soybean oil was determined by gel permeation chromatography for polymerized triacylglycerols and by ¹H-NMR spectroscopy for reactions at reactive sites of soybean oil molecules including olefinic, bisallylic and allylic protons during frying. Sesamol showed lower antioxidant activity than 0.02 % (w/w) tert-butylhydroquinone (TBHQ) at the same molar concentration. Higher concentrations of sesamol provided better antioxidant effects indicating that no prooxidant activity occurred. Sesamol in this frying test showed better results than 0.02 % TBHQ when the concentration was as high as 0.66 % by weight. An HPLC experiment showed that the concentration of sesamol decreased sharply during frying. Thermogravimetric analysis indicated that sesamol is highly volatile and easily oxidizes when exposed to air. To overcome this problem, two multiple addition methods were evaluated in which sesamol was added portion by portion every hour. The multiple additions of divided portions of 0.66 % (w/w) sesamol maintained the concentration of sesamol at the minimum of 0.04–0.06 % throughout the frying process and showed improved antioxidant activity compared to one single addition of 0.66 % sesamol at the beginning of frying. One of the multiple addition methods showed 28, 18, 59, and 27 % less polymerized triacylglycerols and losses of olefinic, bisallylic and allylic protons, respectively, than 0.02 % TBHQ after 8-h frying. This study shows that sesamol can be used as an alternative for synthetic antioxidants for frying oil.     

Oxidative stability of hydrogenated menhaden oil shortening blends in cookies,crackers, and snacks

The oxidative stability of partially hydrogenated menhaden fish oil (PHMO) shortening/canola oil blends with added antioxidant tertiary butylhydroquinone (TBHQ) and various blended partially hydrogenated vegetable oil (PHVO) shortenings without antioxidant in aged cookies and crackers was analyzed by anisidine value (AV), peroxide value (PV), and Totox value. The results showed no significant differences (P<0.05) for PV, AV, or Totox value between the PHMO shortening containing TBHQ and the PHVO shortening in cookies, crackers, and deep-fried extruded snacks, except for the AV and Totox value of crackers.     

Formation of Alkylbenzenes and Tocochromanols Degradation in Sunflower Oil and in Fried Potatoes during Deep‐Frying and Pan‐Frying

Formation of toxic alkylbenzenes, total polar compounds (%TPC) and degradation of tocochromanol are monitored. Analyses of the oil extracted from fried potatoes confirm the trend observed in the frying oil. The fresh oil has a TPC content of 3%, which increases with the frying time, exceeding the acceptable value (25%) after about 25 h for deep‐frying and 1.5 h for pan‐frying. During deep‐frying, total tocochromanol decreases to about half (25 mg per 100 g) of the initial value, pan‐frying shows faster, degradation (complete after 1.5 h). Toluene concentration increases with the frying time reaching a maximum, and afterwards gradually decreases. Except for butylbenzene during pan‐frying, pentylbenzene and butylbenzene concentration, increase with the frying time, but remain much lower than toluene. Practical Applications: This is the first systematic work comparing alkylbenzenes evolution under different frying conditions. Different from previous works, frying experiments are carried out following the indication of many European countries that recommend using temperature lower than 180 °C. The amount of alkylbenzenes assumed through a standard portion of fried potatoes (200 g) is assessed, which is relevant for evaluating dietary exposure to these contaminants.     

Efficacy of myricetin as an antioxidant in methyl esters of soybean oil

The antioxidant activity of myricetin, a natural flavonol found in fruits and vegetables, was determined in soybean oil methyl esters (SME) and compared with α‐tocopherol and tert‐butylhydroquinone (TBHQ) over a 90‐day period employing EN 14112, acid value, and kinematic viscosity methods. Myricetin had greater antioxidant activity than α‐tocopherol, but was inferior to TBHQ. Synergism was observed between myricetin and TBHQ, but antagonism between α‐tocopherol and either myricetin or TBHQ was discovered. A binary mixture of myricetin and TBHQ at 1000 ppm (1:1) was the most effective treatment investigated at inhibiting oxidation of SME. Myricetin was not completely soluble in SME at 1000 ppm, suggesting that 500 ppm is a more appropriate treatment level. Pro‐oxidant activity of α‐tocopherol was observed when added to SME obtained from crude soybean oil, but antioxidant behavior was observed in distilled SME. Addition of α‐tocopherol to methyl esters initially free of antioxidants revealed that 600–700 ppm was the optimum concentration for antioxidant activity. Acid value and kinematic viscosity remained within prescribed specifications after 90 days, despite failure of a number of samples with regard to EN 14112, suggesting that these parameters are insufficient as sole indicators of oxidation stability.     

Efficacy of Microencapsulated Carvacrol in Oxidative Stability of Sunflower Oil

The objective of this study is to improve the oxidative stability of sunflower oil using encapsulated carvacrol during 25 times repeated frying experiments. Microencapsulated carvacrol powders are produced by spray drying using binary and ternary blends of gum arabic (GA), maltodextrin (MD), and corn starch as encapsulating agents. In most cases, the encapsulation efficiency decreases as the amount of GA decreases in the wall mixture. Microencapsulated carvacrol powders prepared with GA (100%), GA + MD (75:25), and GA + MD + starch (67.5: 22.5: 10), which are found to have higher encapsulation efficiency values, are used as antioxidants in dough frying experiments. Frying experiments are performed with the addition of encapsulated and/or unencapsulated forms of carvacrol into the sunflower oil or dough. Encapsulated carvacrol is found to be more effective than unencapsulated carvacrol and butylated hydroxyanisole (BHA) in repeated frying experiments. The addition of carvacrol into oil provides better protection compared to addition into dough. Protective effects of encapsulated and unencapsulated forms of carvacrol in frying trials are successfully discriminated by applying principal component analysis. Practical Application: Carvacrol and thymol are the major constituents of thyme (Thymus vulgaris L.) essential oil. These compounds are responsible for the main bioactive properties of thyme oil. Therefore, in this study, pure commercial carvacrol was encapsulated and tested for its protective effect in sunflower oil during repeated dough frying. The effectiveness of the carvacrol in encapsulated form may be a consequence of the prevention of volatilization. The results of this study are remarkable for food applications requiring high temperatures.