Cialiè Rosso Marta, Stilo Federico, Mascrez Steven, Bicchi Carlo, Purcaro Giorgia, Cordero Chiara
Dipartimento di Scienza e Tecnologia del Farmaco, Università degli Studi di Torino, Via Pietro Giuria 9, I-10125 Torino, Italy.
AgroBioChem Department, Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés 2, 5030 Gembloux, Belgium.
Foods. 2021 Mar 23;10(3):685. doi: 10.3390/foods10030685.
Hazelnuts are characterized by a relatively high abundance of oleic acid and poly-unsaturated fatty acids, which give this fruit a high nutritional value. As a counterbalance, such a lipid profile is more susceptible to autoxidation and/or degradation reactions under enzymatic catalysis. Lipid oxidation occurs on fatty acids (FAs), both esterified on triacylglycerols and in free form (after lipolysis), but with favorable kinetics on the latter. In this study, the quali-quantitative changes in FA profiles (both free and esterified) were monitored during the shelf life (time 0, 6, and 12 months) as a function of different drying and storage conditions and different cultivars and geographical areas. A derivatization/extraction procedure was performed to quantify the profile of free and esterified fatty acids accurately. The overall profile of the free and esterified fatty acids concurred to create a biological signature characteristic of the cultivar and of the harvest region. The free and esterified forms' characterization enabled the efficient monitoring of the effects of both the hydrolytic activity (increment in overall free fatty acids) and the oxidative process (decrease in unsaturated free fatty acids versus esterified fatty acids) over the 12 months of storage.
榛子的特点是油酸和多不饱和脂肪酸含量相对较高，这使得这种果实具有很高的营养价值。作为一种平衡，这种脂质分布在酶催化下更容易发生自氧化和/或降解反应。脂质氧化发生在脂肪酸（FAs）上，脂肪酸既以酯化形式存在于三酰甘油中，也以游离形式存在（脂解后），但后者的反应动力学更有利。在本研究中，在保质期（0、6和12个月）内，监测了不同干燥和储存条件、不同品种以及不同地理区域下脂肪酸谱（游离和酯化）的定性和定量变化。采用衍生化/提取程序准确量化游离脂肪酸和酯化脂肪酸的谱。游离脂肪酸和酯化脂肪酸的总体谱共同形成了品种和收获地区特有的生物学特征。游离和酯化形式的表征能够有效监测储存12个月期间水解活性（总游离脂肪酸增加）和氧化过程（不饱和游离脂肪酸与酯化脂肪酸相比减少）的影响。
