Katarzyna SUJKA, Hanna ?YTKİEWİCZ CİEMNİEWSKA, Piotr KOCZO?, Anna MATLİNGİEWİCZ, Edyta LİPİ?SKA, Magdalena REDER

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

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.

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

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.

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