مجله علوم و صنایع غذایی ایران

مجله علوم و صنایع غذایی ایران

Investigation of the Chemical Composition, Aflatoxin Level, and Phenolic Profile of Hazelnut Skin

نوع مقاله : مقاله پژوهشی

نویسندگان
Kudret ATEŞ 1
Avni ÇAKICI 2
Birsen SARICI 3
1 BEYOĞLU-ISTANBUL
2 Department of Toxicology, Faculty of Pharmacy, Istanbul Aydın University, 342
3 Department of Nutrition and Dietetics, Faculty of Health Sciences, Düzce University, 81620 Düzce, Türkiye.
10.48311/fsct.2025.117604.82926
چکیده
Hazelnut skin is a thin brown coating surrounding the kernel that separates during roasting and is usually discarded as a by-product. However, it is rich in dietary fiber and bioactive compounds that vary by cultivar and region. In this study, the chemical composition and aflatoxin levels of hazelnut skins from Kocaeli and Ordu provinces in Türkiye were analyzed, with phenolic contents evaluated only for the Ordu sample. In the Kocaeli sample, dry matter, ash, fat, and protein contents were 91.07%, 2.14%, 12.94%, and 8.72%, respectively; whereas for the Ordu sample they were 95.38%, 1.90%, 26.55%, and 15.03%. Fourier transform infrared spectroscopy (FTIR) indicated phenolic and lipid functional groups. Ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) showed that isoquercitrin (436.69 µg/g), catechin (270.77 µg/g), and quinic acid (231.64 µg/g) were the major compounds, while rutin (49.09 µg/g), hesperidin (20.46 µg/g), and quercetin (13.87 µg/g) were detected at moderate levels, including some phenolics rarely reported in hazelnut skins. Total aflatoxin in the Ordu sample was below the EU maximum level (10 μg/kg), whereas the Kocaeli sample was close to this limit (9.99 μg/kg). These findings suggest that the Ordu sample contained higher fat, protein, and selected phenolics, supporting its potential use as a functional ingredient. Improved drying and monitoring practices may help reduce aflatoxin G₂ contamination. Further studies are required to confirm bioavailability and safety under different conditions
کلیدواژه‌ها
Hazelnut skin
Proximate composition
Phenolic profile
Aflatoxin
HPLC

موضوعات

عنوان مقاله English

Investigation of the Chemical Composition, Aflatoxin Level, and Phenolic Profile of Hazelnut Skin

نویسندگان English

Kudret ATEŞ 1
Avni ÇAKICI 2
Birsen SARICI 3
1 Department of Food Engineering, Faculty of Engineering, Istanbul Aydın University
2 Department of Toxicology, Faculty of Pharmacy, Istanbul Aydın University, 342
3 Department of Nutrition and Dietetics, Faculty of Health Sciences, Düzce University, 81620 Düzce, Türkiye.
چکیده English

Hazelnut skin is a thin brown coating surrounding the kernel that separates during roasting and is usually discarded as a by-product. However, it is rich in dietary fiber and bioactive compounds that vary by cultivar and region. In this study, the chemical composition and aflatoxin levels of hazelnut skins from Kocaeli and Ordu provinces in Türkiye were analyzed, with phenolic contents evaluated only for the Ordu sample. In the Kocaeli sample, dry matter, ash, fat, and protein contents were 91.07%, 2.14%, 12.94%, and 8.72%, respectively; whereas for the Ordu sample they were 95.38%, 1.90%, 26.55%, and 15.03%. Fourier transform infrared spectroscopy (FTIR) indicated phenolic and lipid functional groups. Ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) showed that isoquercitrin (436.69 µg/g), catechin (270.77 µg/g), and quinic acid (231.64 µg/g) were the major compounds, while rutin (49.09 µg/g), hesperidin (20.46 µg/g), and quercetin (13.87 µg/g) were detected at moderate levels, including some phenolics rarely reported in hazelnut skins. Total aflatoxin in the Ordu sample was below the EU maximum level (10 μg/kg), whereas the Kocaeli sample was close to this limit (9.99 μg/kg). These findings suggest that the Ordu sample contained higher fat, protein, and selected phenolics, supporting its potential use as a functional ingredient. Improved drying and monitoring practices may help reduce aflatoxin G₂ contamination. Further studies are required to confirm bioavailability and safety under different conditions.

کلیدواژه‌ها English

Hazelnut skin
Proximate composition
Phenolic profile
Aflatoxin
HPLC
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