Advertisement

Journal of the American Oil Chemists' Society

, Volume 89, Issue 9, pp 1763–1770 | Cite as

Chemical Composition and Oxidative Stability of Roasted and Cold Pressed Pumpkin Seed Oils

  • Sandra NeđeralEmail author
  • Dubravka Škevin
  • Klara Kraljić
  • Marko Obranović
  • Sunčica Papeša
  • Antonija Bataljaku
Original Paper

Abstract

In the present study, the effects of three production processes (pressing of roasted pumpkin seed paste, pressing of unroasted ground pumpkin seeds and pressing of unroasted ground pumpkin seeds while cooling the press) on the properties of pumpkin seed oils produced from two seed varieties (husked and naked) were investigated. Oils produced with roasting had a higher initial peroxide value (PV), twofold higher total phenol content and better oxidative stability while cold pressed oils had higher tocopherol content. Fatty acid and triacylglycerol compositions were not significantly affected by the processing conditions. Oxidative stability of the oils positively correlated with oleic acid content and negatively correlated with linoleic and linolenic acid contents. The lack of correlation in oxidative stability with tocopherol and polyphenol contents suggests that improvement in oxidative stability of roasted oils could have been caused by antioxidative Maillard reaction products or inactivation of oil degrading enzymes. In addition, oils produced from husked seeds had significantly higher linoleic acid, triacylglycerols (TAG) containing mainly linoleic acid (LLL, OLL and PLL), tocopherol and phenol contents while oleic acid and TAG containing mainly oleic acid (LOO and OOO) contents and oxidative stability were lower. Principal component analysis (PCA) of the analytical data confirmed the observed differences between oils from two varieties and three production processes.

Keywords

Pumpkin seed oil Roasting Pressing Fatty acids Phenols Tocopherols Oxidative stability 

Notes

Acknowledgments

The present work is part of the research project “Stability of Oil and Bioactive Compounds in Oil during Processing and Storage” supported by the Ministry of Science, Education and Sports of the Republic of Croatia.

References

  1. 1.
    CODEX STAN (1999) Codex Standard for edible fats and oils not covered by individual standards. FAO/WHO, Rome (CODEX STAN 19-1981)Google Scholar
  2. 2.
    Narodne Novine (2010) Pravilnik o jestivim uljima i mastima (Regulation on edible oils and fats). Narodne Novine 22/10Google Scholar
  3. 3.
    Murkovic M, Hillebrand A, Winkler J (1996) Variability of fatty acid content in pumpkin seeds (Cucurbita pepo L.). Eur Food Res Technol 203:216–219Google Scholar
  4. 4.
    Nederal Nakic S, Rade D, Skevin D, Strucelj D, Mokrovcak Z, Bartolic M (2006) Chemical characteristics of oils from naked and husk seeds of Cucurbita pepo L. Eur J Lipid Sci Tech 108:936–943CrossRefGoogle Scholar
  5. 5.
    Andjelkovic M, Van Camp J, Trawka A, Verhe R (2010) Phenolic compounds and some quality parameters of pumpkin seed oil. Eur J Lipid Sci Tech 112:208–217CrossRefGoogle Scholar
  6. 6.
    Haiyan Z, Bedgood DR, Bishop AG, Prenzler PD, Robards K (2007) Endogenous biophenol fatty acid and volatile profiles of selected oils. Food Chem 100:1544–1551CrossRefGoogle Scholar
  7. 7.
    Tuberoso CIG, Kowalczyk A, Sarritzu E, Cabras P (2007) Determination of antioxidant compounds and antioxidant activity in commercial oilseeds for food use. Food Chem 103:1494–1501CrossRefGoogle Scholar
  8. 8.
    Murkovic M, Piironen V, Lampi AM, Kraushofer T, Sontag G (2004) Changes in chemical composition of pumpkin seeds during the roasting process for production of pumpkin seed oil (Part 1: non-volatile compounds). Food Chem 84:359–365CrossRefGoogle Scholar
  9. 9.
    Siegmund B, Murkovic M (2004) Changes in chemical composition of pumpkin seeds during the roasting process for production of pumpkin seed oil (Part 2: volatile compounds). Food Chem 84:367–374CrossRefGoogle Scholar
  10. 10.
    Lee YC, Oh SW, Chang J, Kim IH (2004) Chemical composition and oxidative stability of safflower oil prepared from safflower seed roasted with different temperatures. Food Chem 84:1–6CrossRefGoogle Scholar
  11. 11.
    Durmaz D, Gökmen V (2010) Changes in oxidative stability, antioxidant capacity and phytochemical composition of Pistacia terebinthus oil with roasting. Food Chem 128:410–414CrossRefGoogle Scholar
  12. 12.
    Vujasinovic V, Djilas S, Diic E, Romanic R, Takaci A (2010) Shelf life of cold-pressed pumpkin (Cucurbita pepo L.) seed oil obtained with a screw press. J Am Oil Chem Soc 87:1497–1505CrossRefGoogle Scholar
  13. 13.
    ISO (2000) Oilseeds—determination of moisture and volatile matter content. International Organization for Standardization, Geneva (ISO 665)Google Scholar
  14. 14.
    ISO (2006) Oilseed meals—determination of oil content—Part 1: Extraction method with hexane (or light petroleum). International Organization for Standardization, Geneva (ISO 734-1)Google Scholar
  15. 15.
    ISO (2004) Animal and vegetable oils and fats—determination of acid value and of acidity. International Organization for Standardization, Geneva (ISO 660)Google Scholar
  16. 16.
    ISO (2007) Animal and vegetable fats and oils—determination of peroxide value—Iodometric (visual) endpoint determination. International Organization for Standardization, Geneva (ISO 3960)Google Scholar
  17. 17.
    ISO (2000) Animal and vegetable fats and oils—preparation of methyl esters of fatty acids. International Organization for Standardization, Geneva (ISO 5509)Google Scholar
  18. 18.
    ISO (1990) Animal and vegetable oils and fats—analysis by gas chromatography of methyl esters of fatty acids. International Organization for Standardization, Geneva, (ISO 5508)Google Scholar
  19. 19.
    AOAC (2000) Triglycerides (by partition numbers) in vegetable oils liquid chromatographic method. AOAC International, Gaithersburg (Official method 993.24)Google Scholar
  20. 20.
    Butinar B, Bučar-Miklavčič M, Valenčić V, Raspor P (2010) Stereospecific analysis of triacylglycerols as a useful means to evaluate genuineness of pumpkin seed oils: lesson from virgin olive oil analyses. J Agr Food Chem 58:5227–5234CrossRefGoogle Scholar
  21. 21.
    Lísa M, Holčapek M (2008) Triacylglycerols profiling in plant oils important in food industry, dietetics and cosmetics using high-performance liquid chromatography–atmospheric pressure chemical ionization mass spectrometry. J Chromatogr A 1198–1199:115–130Google Scholar
  22. 22.
    ISO (2006) Animal and vegetable fats and oils—determination of tocopherol and tocotrienol contents by high-performance liquid chromatography. International Organization for Standardization, Geneva (ISO 9936)Google Scholar
  23. 23.
    Gutfinger T (1981) Polyphenols in olive oils. J Am Oil Chem Soc 58:966–968CrossRefGoogle Scholar
  24. 24.
    AOCS (1992) Oil Stability Index (OSI). American Oil Chemists’ Society, Urbana (AOCS Official Method Cd 12b-92)Google Scholar
  25. 25.
    Wentzel C (1987) Recent studies on the fatty acid composition of Styrian pumpkin seed oils. Ernährung/Nutrition 11:752–755Google Scholar
  26. 26.
    Younis YMH, Seniat G, Al-Shihry SS (2000) African Cucurbita pepo L.: properties of seed and variability in fatty acid composition of seed oil. Phytochem 54:71–75CrossRefGoogle Scholar
  27. 27.
    Murkovic M, Pfannhauser W (2000) Stability of pumpkin seed oil. Eur J Lipid Sci Tech 102:607–611CrossRefGoogle Scholar
  28. 28.
    Wada S, Koizumi C (1983) Influence of the position of unsaturated fatty acid esterified glycerol on the oxidation rate of triglyceride. J Am Oil Chem Soc 60:1105–1108CrossRefGoogle Scholar
  29. 29.
    Yoshida H, Tomiyamaa Y, Hirakawaa Y, Mizushina Y (2006) Microwave roasting effects on the oxidative stability of oils and molecular species of triacylglycerols in the kernels of pumpkin (Cucurbita spp.) seeds. J Food Compos Anal 19:330–339CrossRefGoogle Scholar
  30. 30.
    Szydłowska-Czerniak A, Karlovits G, Sosna-Sárdi A, Dianoczki C, Szłyk E (2009) Effect of hydrothermal treatment of rapeseed on antioxidant capacity of the pressed rapeseed oil. J Am Oil Chem Soc 86:817–825CrossRefGoogle Scholar
  31. 31.
    Yoshida H, Tatsumi M, Kajimoto G (1991) Relationship between oxidative stability of vitamin E and production of fatty acids in oils during microwave heating. J Am Oil Chem Soc 68:566–570CrossRefGoogle Scholar
  32. 32.
    Talcott ST, Passeretti S, Duncan CE, Gorbet DW (2005) Polyphenolic content and sensory properties of normal and high oleic acid peanuts. Food Chem 90:379–388CrossRefGoogle Scholar
  33. 33.
    Lee SW, Jeung MK, Park MH, Lee SY, Lee JH (2010) Effects of roasting conditions of sesame seeds on the oxidative stability of pressed oil during thermal oxidation. Food Chem 118:681–685CrossRefGoogle Scholar
  34. 34.
    Gorjanović SZ, Rabrenović B, Novaković M, Dimić EB, Basić ZN, Sužnjević DZ (2011) Cold-pressed pumpkin seed oil antioxidant activity as determined by a DC polarographic assay based on hydrogen peroxide scavenge. J Am Oil Chem Soc doi:  10.1007/s11746-011-1863-3
  35. 35.
    Szterk A, Roszko M, Sosińska E, Derewiaka D, Lewicki PP (2010) Chemical composition and oxidative stability of selected plant oils. J Am Oil Chem Soc 87:637–645CrossRefGoogle Scholar
  36. 36.
    Gökmen V, Durmaz D (2010) Impacts of roasting oily seeds and nuts on their extracted oils. Lipid Technol 22:179–182CrossRefGoogle Scholar

Copyright information

© AOCS 2012

Authors and Affiliations

  • Sandra Neđeral
    • 1
    Email author
  • Dubravka Škevin
    • 1
  • Klara Kraljić
    • 1
  • Marko Obranović
    • 1
  • Sunčica Papeša
    • 2
  • Antonija Bataljaku
    • 1
  1. 1.Faculty of Food Technology and BiotechnologyUniversity of ZagrebZagrebCroatia
  2. 2.Department of Health Regulation and ControlKRAŠ Food IndustryZagrebCroatia

Personalised recommendations