Use of FT-IR Spectroscopy Combined with Discriminant Analysis for Identification of Hazelnuts Infected by Aspergillus flavus

Yıl 2014, Cilt: 12 Sayı: 2, 11 - 18, 01.06.2014

Magdalena Reder Edyta Lipińska Hanna Ciemniewska-żytkiewicz Katarzyna Sujka Piotr Koczoń Anna Matlingiewicz

Öz

Fourier-transform infrared FT-IR spectroscopy method developed for the analysis of mold presence in hazelnuts was examined in terms of controlling chemical and microbiological quality of hazelnuts. Following molds growing on hazelnuts stored for 3 months in room temperature were isolated and characterized: Mucor, Rhizopus, Chrysosporium, Verticillium, Penicillium, Aspergillus and Alternaria. IR spectra of hazelnuts in various times of storage were registered. Using both microbiological and spectral data, statistical model discriminating microbiologically pure hazelnuts from hazelnuts contaminated with mold Aspergillus flavus was calculated and validated. The developed methodology may be considered as an alternative approach for rapidly scanning hazelnuts for rapid determination of contamination of hazelnuts by Aspergillus flavus and further for mycotoxins determination

Anahtar Kelimeler

FT-IR, Hazelnuts, Aspergillus flavus

Aspergillus flavus ile Enfekte Olmuş Fındıkların Belirlenmesi için FT-IR Spektroskopisi ve Diskriminant Analiz Kombinasyonu Kullanımı

Öz

Fındıklardaki küf varlığını analiz etmek için geliştirilen Fourier dönüşümlü kızılötesi FT-IR spektroskopi metodunun, fındıkların kimyasal ve mikrobiyolojik kontrollleri için kullanılıp kullanılayacağı araştırılmıştır. Oda sıcaklığında 3 ay depolanan fındıklarda küf gelişimini takiben Mucor, Rhizopus, Chrysosporium, Verticillium, Penicillium, Aspergillus ve Alternaria cinsleri fındıklardan izole ve karakterize edilmiştir. Farklı sürelerde depolanan fındıkların IR spektrumu kaydedilmiştir. Mikrobiyolojik ve spektral data verileri birlikte kullanılarak Aspergillus flavus ile kontamine ve mikrobiyolojik olarak temiz fındıkların ayrımı için istatistiksel model geliştirilmiş ve valide edilmiştir. Geliştirilen metodoloji, fındıklarda Aspergillus flavus ve diğer mikotoksinlerin kontaminasyonunun hızlı bir şekilde belirlenmesi ve fındıkların hızlı taranması için alternatif bir yaklaşım olarak değerlendirilebilir

Anahtar Kelimeler

FT-IR, Fındık, Aspergillus flavus

Kaynakça

• Central Statistical Office of Poland (GUS – Główny Urząd Statystyczny), Database from 2007. http://stat.gov.pl/en/ (access date: 30.03.2014).
• Food and Agriculture Organization of the United Nations (FAOSTAT), Database from 2012. http://faostat.fao.org/, (access date: 12.04.2014).
• Gantner, M., 2010. Current problems in minor crops on hazelnut example. Progress in Plant Protection 50: 1583-1591.
• Commission Regulation (EC) No. 1284/2002 laying down the marketing standard for hazelnuts in shell.
• Commision Regulation (EC) No 1881/2006 setting maximum levels for certain contaminants in foodstuffs.
• Dogan A., Siyakus G., Severcan F., 2007. FTIR spectroscopic characterization of irradiated hazelnut (Corylus avellana L.). Food Chemistry 100: 1106-1114.
• Erukhimovitch, V., Pavlov, V., Talyshinsky, M., Souprun, Y., Huleihel, M., 2005. FTIR microscopy as a method for identification of bacterial and fungal infections. Journal of Pharmaceutical and Biomedical Analisys 37: 1105-1108.
• ISO 6887-1: 1999: Microbiology of food and animal feeding stuffs. Preparation of test samples, initial suspension and decimal dilutions for microbiological examination. General rules for the preparation of the initial suspension and decimal dilutions.
• ISO 4833:2003: Microbiology of food and animal feeding stuffs. Horizontal method for the enumeration of microorganisms. Colony-count technique at 30°C.
• ISO 21527-2:2008: Microbiology of food and animal feeding stuffs. Horizontal method for the enumeration of yeasts and moulds. Colony count technique in products with water activity less than or equal to 0.95.
• Xu, Y., Bianchini, A., Hanna, M. A., 2011. Evaluation of mold and mycotoxin contaminations in hybrid hazelnuts grown in Nebraska. Food Processing and Technology 2(5): 1-4.
• Khorsavi, A.R., Shorki, H., Ziglari, T., 2007. Evaluation of fungal flora in some important nut products (pistachio. peanut. hazelnut and almond) in Tehran. Pakistan Journal of Nutrition 6(5): 460- 462.
• Basaran, P., Demirbas, R.M., 2010. Spectroscopic detection of pharmaceutical compounds from an aflatoxigenic strain of Aspergillus parasiticus. Microbiological Research 165(6): 516-522.