TURUNÇGİL KABUK ATIKLARINDAN ALKALİ EKSTRAKSİYON İLE ELDE EDİLEN PEKTİNCE ZENGİN BİLEŞEN BAZLI FİLMLERİN YAPISAL VE SU BUHARI BARİYER ÖZELLİKLERİNİN İNCELENMESİ

Abstract

Bu çalışmada, portakal, mandalina, limon ve pomelo gibi turunçgil kabuklarından alkali koşullar altında (50 mM NaOH) ekstrakte edilen pektin açısından zengin bileşiklerden elde edilen filmlerin yapısal ve su buharı geçirgenlik özellikleri incelenmiştir. Alkali işlem, limon, portakal ve pomelo kabuklarında önemli ölçüde de-esterleşmeye yol açarak düşük metoksilli pektin (DE<%50) elde edilmesini sağlarken, sadece mandalina ekstraktının yüksek metoksil yapısını koruduğu gözlenmiştir (%64.63) (P<0.05). Filmler, ekstraktların gliserol ile plastikleştirilmesi ve CaCl2 ile çapraz bağlanmasıyla üretilmiştir. Taramalı elektron mikroskobu ve Fourier dönüşümlü kızılötesi spektroskopisiyle gerçekleştirilen fiziksel karakterizasyon, alkali koşulların β-eliminasyon ve sabunlaşma reaksiyonları aracılığıyla olası yapısal değişimlere neden olarak yüzey düzensizlikleri ve yüksek su buharı geçirgenliğine sahip filmler oluştuğunu, özellikle portakal kabuğu ekstraktı bazlı filmlerde en yüksek geçirgenliğin (39.69 g·mm/(kPa·h·m²)) gözlendiğini göstermiştir. Sonuç olarak; alkali ekstraksiyonun turunçgil kabuklarından düşük metoksilli pektince zengin bileşen eldesinde etkili olduğu, ancak elde edilen filmlerin su bariyeri ve yapısal bütünlük açısından gıda ambalajı olarak kullanılabilmesi için performanslarının optimize edilmesi gerektiği belirlenmiştir.

Keywords

• Turunçgil kabukları
• atık değerlendirme
• pektince zengin bileşik
• alkali ekstraksiyon
• biyopolimer film
• çapraz bağlanma
• su buharı geçirgenliği

INVESTIGATION OF STRUCTURAL AND WATER VAPOR BARRIER PROPERTIES OF PECTIN-RICH COMPOUND BASED FILMS EXTRACTED FROM CITRUS PEEL WASTES VIA ALKALINE EXTRACTION

Abstract

In this study, the film-forming potential of pectin-rich compounds extracted from various citrus peels including orange, tangerine, lemon, and pomelo under alkaline condition (50 mM NaOH) was investigated. Alkali treatment resulted in significant de-esterification, yielding low-methoxyl pectin (DE<50%), whereas tangerine extract retained a high-methoxyl structure (64.63%) (P<0.05). Films were fabricated by plasticizing the extracts with glycerol and crosslinking with CaCl2. Physical characterization including scanning electron microscopy and Fourier transform infrared spectroscopy showed that alkaline conditions caused potential structural changes via β-elimination and saponification reactions, resulting in fi lms with surface irregularities and high-water vapor permeability, specifically highest in orange peel extract-based films (39.69 g·mm/(kPa·h·m²)). In conclusion, alkali extraction was found to be effective in obtaining low-methoxyl pectin-rich compounds from citrus peels; however, it was determined that the performance of the resulting films needs to be optimized to ensure their suitability for food packaging applications.

Keywords

• Citrus peels
• waste valorization
• pectin rich compounds
• alkali extraction
• biopolymer film
• crosslinking
• water vapor permeability

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