IN VITRO GASTROİNTESTİNAL SİSTEMDE HİNDİSTAN CEVİZİ YAĞININ FİZİKOKİMYASAL ÖZELLİKLERİ VE YAĞ ASİDİ PROFİLİ

Öz

Bu çalışmada, ağız, mide ve bağırsak evrelerini simüle eden yarı dinamik bir in vitro gastrointestinal sistem kullanarak soğuk preslenmiş, rafine edilmemiş Hindistan cevizi yağının sindirim sırasındaki fizikokimyasal değişimleri araştırılmıştır. Serbest yağ asitliği, peroksit değeri, kırılma indisi, iyot değeri, yağ asidi bileşimi ve sterol profili gibi temel parametreler analiz edilmiş; istatistiksel farklar tek yönlü ANOVA ile değerlendirilmiştir. Sindirim, özellikle bağırsak evresinde serbest yağ asitlerinde anlamlı bir artışa (P<0.05) yol açarak belirgin lipaz aracılı hidrolizi ortaya koymuştur. Peroksit değeri, iyot sayısı ve kırılma indisi de sindirim evreleri arasında değişim gösterirken, yağ asidi ve sterol profilleri faza bağlı farklılıklar sergilemiştir. Bulgular, Hindistan cevizi yağının özellikle bağırsak enzimatik aktivitesi altında önemli fizikokimyasal dönüşümlere uğradığını göstermektedir. Çalışma, diyet yağlarının beslenme davranışı ve stabilitesini değerlendirirken gastrointestinal simülasyon modellerinin önemini vurgulamaktadır.

Anahtar Kelimeler

• Hindistan cevizi yağı
• yağ asidi
• sterol
• in vitro gastrointestinal sistem
• gıda
• beslenme

PHYSICOCHEMICAL PROPERTIES AND FATTY ACID PROFILE OF COCONUT OIL IN AN IN VITRO GASTROINTESTINAL SYSTEM

Öz

This study investigated the physicochemical changes of cold-pressed, unrefined coconut oil during digestion using a semi-dynamic in vitro gastrointestinal system that simulates the mouth, gastric, and intestinal phases. Key parameters-including free fatty acidity, peroxide value, refractive index, iodine value, fatty acid composition, and sterol profile-were analyzed, and statistical differences were evaluated by one-way ANOVA. Digestion led to significant alterations in several indices, notably a marked increase in free fatty acids in the intestinal phase (P<0.05), indicating extensive lipase-mediated hydrolysis. Peroxide value, iodine number, and refractive index also changed across phases, while fatty acid and sterol profiles exhibited phase-dependent shifts. These findings demonstrate that coconut oil undergoes significant physicochemical transformations during digestion, particularly under the influence of intestinal enzymatic activity. The study highlights the importance of gastrointestinal simulation when assessing the nutritional behavior and stability of dietary oils.

Anahtar Kelimeler

• Coconut oil
• fatty acid
• sterol
• in vitro gastrointestinal system
• food
• nutrition

Kaynakça

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