Nitra, Slovakia
Nitra, Slovakia
Nitra, Slovakia
Nitra, Slovakia
Nitra, Slovakia
Nitra, Slovakia
Bratislava, Slovakia
Nitra, Slovakia
This study aimed to evaluate the oxidative stability of rapeseed oil, changes in the fatty acid profile, and acrylamide formation in French fries during their deep-frying in Slovak catering establishments. Their nutritional benefits and potential health risks were assessed by chemical, textural, and sensory analyses. The primary materials for all analyses were raw potato fries and frozen pre-fried French fries. Chemical and physical degradation of the frying oil was monitored using total polar compounds measured with a Testo 270 tester and the peroxide value determination, while the acid value was determined via titration with potassium hydroxide. Textural analysis of the potato fries was performed using a TA.XT plus texture analyzer to quantify parameters like hardness and crispness, followed by a sensory evaluation conducted by a panel using a 9-point hedonic scale. Frozen pre-fried French fries were deep-fried in rapeseed oil at 175°C/4 min and 200°C/3 min until total polar compounds reached 24%. Textural properties were assessed before and after deep-frying of raw and frozen pre-fried French fries, while their sensory evaluation followed the first deep-frying. Rapeseed oil remained stable longer at 175°C/4 min (22.5 h) than at 200°C/3 min (20.5 h). Peroxide values increased by 66% at 175°C and by 33% at 200°C. Acid values increased by 50% at 175°C and by 33% at 200°C. The content of polyunsaturated fatty acids decreased, while that of monounsaturated fatty acids increased (p ≤ 0.05). Acrylamide levels were within legal limits (< 500 µg/kg). Higher frying temperatures (200°C) increased crispness but reduced breaking force and hardness. Raw fries had higher strength and crispness at pre-frying, while frozen pre-fried fries exhibited lower crispness. Sensory evaluation favored semi-finished products over raw potato fries, with better ratings for color, aroma, and taste. Shorter, high-temperature frying significantly affected the textural changes (p ≤ 0.05), while lower temperatures (175°C) had a greater effect on hardness than breaking force. Overall, deep-fried pre-fried French fries were preferred in the sensory tests. Our findings provide scientifically based information for optimizing frying processes to improve the quality of French fries and support the development of innovative recipes in catering establishments.
Frying, potato, rapeseed oil, catering, acrylamide formation, oxidation, food safety
1. Sales-Campos H, Reis de Souza P, Crema Peghini B, Santana da Silva J, Ribeiro Cardoso C. An overview of the modulatory effects of oleic acid in health and disease. Mini Reviews in Medicinal Chemistry. 2013;13(2):201–210. https://doi.org/10.2174/138955713804805193
2. Abd Razak RA, Ahmad Tarmizi AH, Kuntom A, Sanny M, Ismail IS. Intermittent frying effect on French fries in palm olein, sunflower, soybean and canola oils on quality indices, 3-monochloropropane-1,2-diol esters (3-MCPDE), glycidyl esters (GE) and acrylamide contents. Food Control. 2021;124:107887. https://doi.org/10.1016/j.foodcont.2021.107887
3. Zhang Q, Qin W, Lin D, Shen Q, Saleh ASM. The changes in the volatile aldehydes formed during the deep-fat frying process. Journal of Food Science and Technology. 2015;52:7683–7696. https://doi.org/10.1007/s13197-015-1923-z
4. Arefi A, Hensel O, Sturm B. Intelligent potato frying: Time to say goodbye to the “good old” processing strategies. Thermal Science and Engineering Progress. 2022;34:101389. https://doi.org/10.1016/j.tsep.2022.101389
5. Asokapandian S, Swamy GJ, Hajjul H. Deep fat frying of foods: A critical review on process and product parameters. Critical Reviews in Food Science and Nutrition. 2020;60(20):3400–3413. https://doi.org/10.1080/10408398.2019.1688761
6. Rodrigues N, Silva K, Veloso ACA, Pereira JA, Peres AM. The use of electronic nose as alternative non-destructive technique to discriminate flavored and unflavored olive oils. Foods. 2021;10(11):2886. https://doi.org/10.3390/foods10112886
7. Castro RC, Ribeiro DSM, Santos JLM, Páscoa RNMJ. The use of in-situ Raman spectroscopy to monitor at real time the quality of different types of edible oils under frying conditions. Food Control. 2022;136:108879. https://doi.org/10.1016/j.foodcont.2022.108879
8. García Martín JF. Potential of near-infrared spectroscopy for the determination of olive oil quality. Sensors. 2022;22(8):2831. https://doi.org/10.3390/s22082831
9. Sâmia RR, Lorenzo ND, Lessa Barbosa BV, Fonseca ALF, Nunes CA, et al. Lipid quality of fried and scrambled eggs prepared in different frying medium. International Journal of Gastronomy and Food Science. 2022;29:100552. https://doi.org/10.1016/j.ijgfs.2022.100552
10. Pardeshi DS. Evaluation of changes in chemical properties of different cooking oils sold in local market before and after frying. International Journal for Research in Applied Science and Engineering Technology. 2020;8(8):1510–1515. https://doi.org/10.22214/ijraset.2020.31138
11. Li X, Wu G, Yang F, Meng L, Huang J, et al. Influence of fried food and oil type on the distribution of polar compounds in discarded oil during restaurant deep frying. Food Chemistry. 2019;272:12–17. https://doi.org/10.1016/j.foodchem.2018.08.023
12. Geng L, Zhou W, Qu X, Sa R, Liang J, et al. Iodine values, peroxide values and acid values of Bohai algae oil compared with other oils during the cooking. Heliyon. 2023;9(4):e15088. https://doi.org/10.1016/j.heliyon.2023.e15088
13. Yang X, Pei J, He X, Wang Y, Wang L, et al. A novel method for determination of peroxide value and acid value of extra-virgin olive oil based on fluorescence internal filtering effect correction. Food Chemistry. 2024;441:138342. https://doi.org/10.1016/j.foodchem.2023.138342
14. Koh E, Surh J. Food types and frying frequency affect the lipid oxidation of deep frying oil for the preparation of school meals in Korea. Food Chemistry. 2015;174:467–472. https://doi.org/10.1016/j.foodchem.2014.11.087
15. Bellés M, del Mar Campo M, Roncalés P, Beltrán JA. Supranutritional doses of vitamin E to improve lamb meat quality. Meat Science. 2019;149:14–23. https://doi.org/10.1016/j.meatsci.2018.11.002
16. Han X, Ye H. Overview of lipidomic analysis of triglyceride molecular species in biological lipid extracts. Journal of Agricultural and Food Chemistry. 2021;69(32):8895–8909. https://doi.org/10.1021/acs.jafc.0c07175
17. Bou R, Navas JA, Tres A, Codony R, Guardiola F. Quality assessment of frying fats and fried snacks during continuous deep-fat frying at different large-scale producers. Food Control. 2012;27(1):254–267. https://doi.org/10.1016/j.foodcont.2012.03.026
18. Kaur A, Singh B, Kaur A, Singh N. Changes in chemical properties and oxidative stability of refined vegetable oils during short‐term deep‐frying cycles. Journal of Food Processing Preservation. 2020;44(6):e14445. https://doi.org/10.1111/jfpp.14445
19. Zárate R, el Jaber‐Vazdekis N, Tejera N, Pérez JA, Rodríguez C. Significance of long chain polyunsaturated fatty acids in human health. Clinical and Translational Medicine. 2017;6(1):e25. https://doi.org/10.1186/s40169-017-0153-6
20. Rotondo A, La Torre GL, Dugo G, Cicero N, Santini A. Oleic acid is not the only relevant mono-unsaturated fatty ester in olive oil. Foods. 2020;9(4):384. https://doi.org/10.3390/foods9040384
21. den Hartigh LJ. Conjugated linoleic acid effects on cancer, obesity, and atherosclerosis: A review of pre-clinical and human trials with current perspectives. Nutrients. 2019;11(2):370. https://doi.org/10.3390/nu11020370
22. Quasmi MN, Kumar D, Jangra A. Effects of dietary acrylamide on kidney and liver health: Molecular mechanisms and pharmacological implications. Toxicology Reports. 2025;14:101859. https://doi.org/10.1016/j.toxrep.2024.101859
23. EFSA Panel on Contaminants in the Food Chain (CONTAM). Scientific Opinion on acrylamide in food. EFSA Journal. 2015;13(6):4104. https://doi.org/10.2903/j.efsa.2015.4104
24. Schouten MA, Tappi S, Glicerina V, Rocculi P, Angeloni S, et al. Formation of acrylamide in biscuits during baking under different heat transfer conditions. LWT. 2022;153:112541. https://doi.org/10.1016/j.lwt.2021.112541
25. Cheng L, Jin C, Zhang Y. Investigation of variations in the acrylamide and Nε‐(Carboxymethyl) lysine contents in cookies during baking. Journal of Food Science. 2014;79(5):T1030–T1038. https://doi.org/10.1111/1750-3841.12450
26. Isik B, Sahin S, Sumnu G. Pore development, oil and moisture distribution in crust and core regions of potatoes during frying. Food and Bioprocess Technology. 2016;9:1653–1660. https://doi.org/10.1007/s11947-016-1748-4
27. Zeleňáková L, Angelovičová M, Šnirc M, Žiarovská J, Kráčmar S, et al. Thermo-degradative changes of rapeseed and sunflower oils during deep-frying French fries. Potravinarstvo Slovak Journal of Food Sciences. 2019;13(1):138–149. https://doi.org/10.5219/1080
28. Wang S, Zhao S, Wang N, Lu Q, Zhao H, et al. Intelligence detection of oil absorption in French fries by surface profiles. Food Research International, 2024;178:113906. https://doi.org/10.1016/j.foodres.2023.113906
29. van der Sman RGM, Schenk E. Causal factors concerning the texture of French fries manufactured at industrial scale. Current Research in Food Science. 2024;8:100706. https://doi.org/10.1016/j.crfs.2024.100706
30. Joyner HS. Explaining food texture through rheology. Current Opinion in Food Science. 2018;21:7–14. https://doi.org/10.1016/j.cofs.2018.04.003
31. Gouyo T, Rondet É, Mestres C, Hofleitner C, Bohuonet P. Microstructure analysis of crust during deep-fat or hot-air frying to understand French fry texture. Journal of Food Engineering. 2021;298:110484. https://doi.org/10.1016/j.jfoodeng.2021.110484
32. Li P, Wu G, Yang D, Zhang H, Qi X, et al. Applying sensory and instrumental techniques to evaluate the texture of French fries from fast food restaurant. Journal of Texture Studies. 2020;51(3):521–531. https://doi.org/10.1111/jtxs.12506
33. Teruel MR, Gordon M, Linares MB, Garrido MD, Ahromrit A, et al. A comparative study of the characteristics of french fries produced by deep fat frying and air frying. Journal of Food Science. 2015;80(2):E349–E358. https://doi.org/10.1111/1750-3841.12753
34. Millin TM, Medina-Meza IG, Walters BC, Huber KC, Rasco BA, et al. Frying oil temperature: Impact on physical and structural properties of french fries during the par and finish frying processes. Food and Bioprocess Technology. 2016;9:2080–2091. https://doi.org/10.1007/s11947-016-1790-2
35. Quan X, Zhang M, Fang Z, Liu H, Shen Q, et al. Low oil French fries produced by combined pre-frying and pulsed-spouted microwave vacuum drying method. Food and Bioproducts Processing. 2016;99:109–115. https://doi.org/10.1016/j.fbp.2016.04.008
36. Amaral RDA, Benedetti BC, Pujola M, Achaerandio I, Bachelli MLB. Effect of ultrasound on quality of fresh-cut potatoes during refrigerated storage. Food Engineering Reviews. 2014;7:176–184. https://doi.org/10.1007/s12393-014-9091-x
37. Ciesarova Z, Kukurova K, Bednarikova A, Morales FJ. Effect of heat treatment and dough formulation on the formation of Maillard reaction products in fine bakery products – benefits and weak points. Journal of Food and Nutrition Research. 2009;48(1):20–30.
38. Yin P, Fan X. Estimating R2 shrinkage in multiple regression: A comparison of different analytical methods. The Journal of Experimental Education. 2001;69(2):203–224. https://doi.org/10.1080/00220970109600656
39. Zeleňáková L, Angelovičová M, Šnirc M, Žiarovská J, Kráčmar S, et al. Is rapeseed oil suitable for frying French fries? 7th Meeting on Chemistry and Life. 2018;16(6):70.
40. Xu L, Mei X, Wu G, Karrar E, Jin Q, et al. Inhibitory effect of antioxidants on key off-odors in French fries and oils and prolong the optimum frying stage. LWT. 2022;162:113417. https://doi.org/10.1016/j.lwt.2022.113417
41. Li X, Wu G, Wu Y, Karrar E, Huang J, et al. Effectiveness of the rapid test of polar compounds in frying oils as a function of environmental and compositional variables under restaurant conditions. Food Chemistry. 2020;312:126041. https://doi.org/10.1016/j.foodchem.2019.126041
42. Chen WA, Chiu CP, Cheng WC, Hsu CK, Kuo MI. Total polar compounds and acid value of repeatedly used frying oils measured by standard and rapid methods. Journal of Food and Drug Analysis. 2013;21(1):58–65. https://doi.org/10.6227/jfda.2013210107
43. Li X, Xing C, Wang Z, Chen Z, Sun W, et al. Validity of total polar compound and its three components in monitoring the evolution of epoxy fatty acids in frying oil: Fast food restaurant conditions. Food Chemistry. 2023;405(Part B):134945. https://doi.org/10.1016/j.foodchem.2022.134945
44. Cebi N, Yilmaz MT, Sagdic O, Yuce H, Yelboga E, et al. Prediction of peroxide value in omega-3 rich microalgae oil by ATR-FTIR spectroscopy combined with chemometrics. Food Chemistry. 2017;225:188–196. https://doi.org/10.1016/j.foodchem.2017.01.013
45. Hassanien MFR, Sharoba AM. Rheological characteristics of vegetable oils as affected by deep frying of French fries. Food Measure. 2014;8:171–179. https://doi.org/10.1007/s11694-014-9178-3
46. Kalogianni EP, Georgiou D, Romaidi M, Exarhopoulos S, Petridis D, et al. Rapid methods for frying oil quality determination: Evaluation with respect to legislation criteria. Journal of the American Oil Chemists’ Society. 2017;94(1):19–36. https://doi.org/10.1007/s11746-016-2919-1
47. Zeleňáková L, Angelovičová M, Šnirc M, Žiarovská J, Kráčmar S, et al. Frying quality characteristics of rapeseed oil used for French fries production. Czech Chemical Society. Symposium Series. 2018;16(6):522–527.
48. Brand TS, van der Westhuizen EJ, van der Merwe DA, Hoffman LC. Analysis of carcass characteristics and fat deposition of Merino, South African Mutton Merino and Dorper lambs housed in a feedlot. South African Journal of Animal Science. 2018;48(3):477–488. https://doi.org/10.4314/sajas.v48i3.8
49. Ciesarová Z, Kukurová K, Zilic S. What changes does the new legislation on acrylamide bring? Food safety and control: Proceedings of professional papers. In: Golian J, Čapla J, editors. Nitra: Garmond Nitra; 2024, pp. 21–28. https://doi.org/10.15414/2024.bkp24-zop
50. Skinner MM, Seale JT, Cantrell MS, Collins JM, Turner MW, et al. Instrumentation for routine analysis of acrylamide in french fries: Assessing limitations for adoption. Foods. 2021;10(9):2038. https://doi.org/10.3390/foods10092038
51. Sanny M, Luning PA, Jinap S, Bakker EJ, van Boekel MAJS. Effect of frying instructions for food handlers on acrylamide concentration in French fries: An explorative study. Journal of Food Protection. 2013;76(3):462–472. https://doi.org/10.4315/0362-028X.JFP-12-049
52. Muttucumaru N, Powers SJ, Elmore JS, Dodson A, Briddon A, et al. Acrylamide-forming potential of potatoes grown at different locations, and the ratio of free asparagine to reducing sugars at which free asparagine becomes a limiting factor for acrylamide formation. Food Chemistry. 2017;220:76–86. https://doi.org/10.1016/j.foodchem.2016.09.199
53. Gabašová M, Zeleňáková L, Ciesarová Z, Benešová L, Kukurová K, et al. The variability of acrylamide content in potato French fries depending on the oil used and deep-frying conditions. Potravinarstvo Slovak Journal of Food Sciences. 2023;17:170–184. https://doi.org/10.5219/1857
54. Vinci RM, Mestdagh F, van Poucke C, van Peteghem C, de Meulenaer B. A two-year investigation towards an effective quality control of incoming potatoes as an acrylamide mitigation strategy in French fries. Food Additives and Contaminants: Part A. 2011;29(3):362–370. https://doi.org/10.1080/19440049.2011.639094
55. Dong L, Qiu C, Wang R, Zhang Y, Wang J, et al. Effects of air frying on French fries: The indication role of physicochemical properties on the formation of maillard hazards, and the changes of starch digestibility. Frontiers in Nutrition. 2022;9:889901. https://doi.org/10.3389/fnut.2022.889901
56. Heredia A, Castelló ML, Argüelles A, Andrés A. Evolution of mechanical and optical properties of French fries obtained by hot air-frying. LWT – Food Science and Technology. 2014;57(2):755–760. https://doi.org/10.1016/j.lwt.2014.02.038
57. Botero-Uribe M, Fitzgerald M, Gilbert RG, Midgley J. Effect of pulsed electrical fields on the structural properties that affect French fry texture during processing. Trends in Food Science & Technology. 2017;67:1–11. https://doi.org/10.1016/j.tifs.2017.05.016
58. Pedreschi F, Mariotti MS, Cortés P. Fried and dehydrated potato products. Advances in Potato Chemistry and Technology. NY: Academic Press; 2016, pp. 459–474. https://doi.org/10.1016/B978-0-12-800002-1.00015-7
59. Li P, Wu G, Yang D, Zhang H, Qi X, et al. Applying sensory and instrumental techniques to evaluate the texture of French fries from fast food restaurant. Journal of Texture Studies. 2020;51(3):521–531. https://doi.org/10.1111/jtxs.12506
60. Navas BP, Ledezma JC, Martinez S. Sensory characteristics of French fries using seasoned oils for frying. SciELO Analytics. 2015;27(2):286–292.
