A NATURAL FOOD FORTIFICATION APPROACH TO REDUCE IRON-POLYPHENOL COMPLEX FORMATION: ORANGE PEEL-ADDED BLACK TEA

Abstract

This study aims to develop a novel functional beverage through a food-to-food fortification strategy to reduce the prevalence of iron deficiency. Hot and cold infusions were prepared with varying orange peel concentrations. The addition of orange peel to black tea prevented the iron-polyphenol complex formation by up to 70%, while tea pH significantly affected iron-binding capacity. The antioxidant activity and total polyphenol content of hot infusions were found to be higher than cold infusions. Addition of orange peel to tea samples decreased the antioxidant activity of tea according to 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays, while hydroxyl radical scavenging activity increased. Sensory evaluation revealed that black tea containing 12% orange peel was the most promising sample, based on consumer acceptance. These findings highlight the potential of orange peel-fortified functional tea as a promising strategy for combating iron deficiency while preserving the characteristic sensory qualities of traditional tea.

Keywords

• Black tea
• orange peel
• inhibition of iron-polyphenol complex
• antioxidant activity
• total polyphenol content
• sensory analysis

Supporting Institution

TUBITAK

Project Number

TUBITAK/2209-A University Student Research Program.

Ethical Statement

Not applicable

Thanks

We gratefully acknowledge the financial support provided by TÜBİTAK (The Scientific and Technological Research Council of Türkiye) through the 2209-A University Student Research Program.

DEMİR-POLİFENOL KOMPLEKSİ OLUŞUMUNU AZALTMAYA YÖNELİK DOĞAL BİR GIDA ZENGİNLEŞTİRME YAKLAŞIMI: PORTAKAL KABUĞU KATKILI SİYAH ÇAY

Abstract

Bu çalışma, demir eksikliği prevalansını azaltmak için gıdadan gıdaya zenginleştirme stratejisi yoluyla yeni bir fonksiyonel içecek geliştirmeyi amaçlamaktadır. Farklı portakal kabuğu konsantrasyonları kullanılarak sıcak ve soğuk infüzyonlar hazırlanmıştır. Siyah çaya portakal kabuğu ilavesi, demir-polifenol kompleksinin oluşumunu %70'e kadar önlerken, çayın pH değeri demir bağlama kapasitesini önemli ölçüde etkilemiştir. Sıcak infüzyonların antioksidan aktivitesi ve toplam polifenol içeriği soğuk infüzyonlardan daha yüksek bulunmuştur. Çay örneklerine portakal kabuğu eklenmesi, 2,2-diphenyl-1-picrylhydrazyl (DPPH) ve 2,2′-azino-bis(3ethylbenzothiazoline-6-sulfonic acid) (ABTS) yöntemlerine göre çayın antioksidan aktivitesini azaltırken, hidroksil radikali süpürme yöntemine göre ise antioksidan aktivitesini artırmıştır. Duyusal analizler ise tüm örnekler arasından %12 portakal kabuğu içeren siyah çayın tüketici kabulü açısından en umut verici örnek olduğunu ortaya koymuştur. Bu bulgular, geleneksel çayın karakteristik duyusal özelliklerini korurken demir eksikliğiyle mücadele için umut verici bir strateji olarak portakal kabuğu ile zenginleştirilmiş fonksiyonel çayın potansiyelini vurgulamaktadır.

Keywords

• Siyah çay
• portakal kabuğu
• demir-polifenol kompleksi inhibisyonu
• antioksidan aktivite
• toplam polifenol içeriği
• duyusal analiz

Supporting Institution

TUBITAK

Project Number

TUBITAK/2209-A University Student Research Program.

Ethical Statement

Not applicable

Thanks

We gratefully acknowledge the financial support provided by TÜBİTAK (The Scientific and Technological Research Council of Türkiye) through the 2209-A University Student Research Program.

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