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A Generalized Method for Determining Free Soluble Phenolic Acid Composition and Antioxidant Capacity of Cereals and Legumes
Published on: June 10, 2022
Polyphenolic composition of hazelnut skin.
Daniele Del Rio1, Luca Calani, Margherita Dall'Asta
1The φ2 Laboratory of Phytochemicals in Physiology, Human Nutrition Unit, Department of Public Health, University of Parma, Via Volturno, 43125 Parma, Italy. daniele.delrio@unipr.it
Journal of Agricultural and Food Chemistry
|August 9, 2011
Summary
Hazelnut skins are rich in polyphenols, primarily flavan-3-ols, and possess high antioxidant capacity. This study characterizes these compounds, highlighting their potential as a valuable health-promoting byproduct.
Area of Science:
- Food Chemistry
- Nutritional Science
- Agricultural Byproducts
Background:
- Hazelnut skins are a significant byproduct of hazelnut processing.
- Understanding the phytochemical composition of hazelnut skins is crucial for valorization.
- Polyphenols are known for their antioxidant properties and potential health benefits.
Purpose of the Study:
- To characterize the total polyphenol content and total antioxidant capacity (TAC) of hazelnut skins.
- To identify and quantify specific polyphenolic compounds within hazelnut skins.
- To compare the TAC of hazelnut skins with other common food items.
Main Methods:
- HPLC-MS/MS was employed for the identification and quantification of polyphenolic compounds.
- Total polyphenol content was determined using spectrophotometric methods.
- Total antioxidant capacity (TAC) was assessed by measuring the moles of reduced iron per kilogram of sample.
Main Results:
- Monomeric and oligomeric flavan-3-ols constituted over 95% of the total identified polyphenols in hazelnut skins.
- Flavonols and dihydrochalcones represented 3.5%, while phenolic acids were less than 1%.
- TAC values ranged from 0.6 to 2.2 mol Fe(II)/kg, significantly exceeding that of walnuts, dark chocolate, coffee, and blackberries.
Conclusions:
- Hazelnut skins are a rich source of flavan-3-ols and exhibit substantial antioxidant activity.
- The high TAC of hazelnut skins suggests significant potential for health-promoting applications.
- Further research into the health effects of hazelnut skins is warranted due to their potent antioxidant profile.
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