Ayse Tulin Oz

Comparison of lipids, fatty acids and volatile compounds of various kumquat species using HS/GC/MS/FID techniques

BACKGROUND Kumquat (Fortunella spp.) is one of the important fruit species that has been introduced into Turkey recently. It is well adapted to the Mediterranean region in Turkey. Early research of kumquat was started on adaptation and pomological traits, and only a few studies have been concerned with chemical content. After understanding the health benefits of kumquat fruits farmers started their plantations in Turkey. Thus in this study the fruits of five kumquat species - Fortunella margarita (Lour.) Swingle, F. crassifolia Swingle, F. obovata Hort. ex Tanaka, F. hindsii (Champ. ex Benth.) Swingle, and limequat [Citrus aurantifolia × F. japonica (Thumb.)] - were compared based on their lipids, fatty acids and volatile profiles. The lipids, fatty acids and volatile profiles were determined by using gas chromatography with flame ionisation detection (GC/FID) and headspace gas chromatography mass spectrometry (HS-GC/MS) techniques. Volatile constituents of kumquat fruits were isolated by a headspace method. RESULTS The total lipid content (%) of kumquat species ranged from 0.26% to 0.37%. The polyunsaturated fatty acids were detected in a higher amount compared to the monounsaturated fatty acids and saturated fatty acids, respectively. The headspace technique led to the identification of 39 compounds and among a total of 39 constituents identified, d-limonene was the most abundant compound, comprising 67.78-88.72%. The results indicated that kumquats are rich in dietary and health benefits. CONCLUSION Thirty-nine compounds were identified and terpenes were the major chemical group in all kumquat genotypes. Esters, alcohols, aldehydes and ketones were also detected. The present study revealed that the kumquat fruits have a valuable levels of health beneficial chemo-preventive effects and genotypes varied based on their lipid, fatty acids and volatile constituents.

Phytochemicals in Fruits and Vegetables

Fruits and vegetables are the most important sources of phytochemicals. Phytochemicals use for both human diets and natural antimicrobial agents in food preservation. Their benefits for health are mainly due to high antioxidant activity. Antimicrobials of plant origin are known as secondary metabolites that could play a role not only individually or jointly against food‐borne pathogens but also contribute to food flavor. Phytochemicals have a strong effect on control and prevention of natural spoilage processes and growth of microorganisms, including pathogens causing food safety issues. Microorganisms are always associated with harvested plants and slaughtered animals, the basic unprocessed materials of the food industry. Since foods consumed by humans undergo several pro‐ cessing treatments, it is important to understand the effect of such treatments on the phytochemical composition of foods.

Muhafaza Süresinin ‘Festival’ Çilek Çeşidi Meyvelerinin Bazı Fitokimyasal Bileşimine Etkisi

Bu arastirmada, Festival’ cilek cesidinin meyvelerinde 12 gun sureyle polivenilpropilen (PVPP) ambalajlarda +5°C sicaklik ve %85-90 oransal nemde muhafaza suresince; fiziksel ve seker ve organik asit gibi fitokimyasal, degisimleri belirlenmistir. Muhafaza sonunda, cilek meyvelerinin ortalama agirlik kaybi ve meyve [L (parlaklik), a* (-yesil, +kirmizi), b*(-sari, +mavi) renk degerinde meydana gelen degisimlerin istatistiksel olarak anlamli olmadigi saptanmistir. Meyve eti sertligi derim zamaninda 2.93 N iken muhafaza sonunda 1.4 N’a dusmustur. Derim zamani SCKM miktari %11.2 iken muhafaza suresince %9.95’e dusmustur. Depolama suresinin sonunda, cilek meyve suyunda toplam fenolik madde miktari 142.55 mg/100mL ve toplam flavonoid madde miktari ise 26.16 mg/100mL olarak saptanmistir. ‘Festival’ cilek cesidi antosiyanin madde miktarinda muhafaza suresince dususler gorulmus ve muhafaza sonunda 163.71 mg/100mL olarak belirlenmistir.