The University of Adelaide, School of Agriculture, Food and Wine, PMB 1, Glen Osmond, SA 5064, Australia.
The Australian Research Council Training Centre for Innovative Wine Production, PMB 1, Glen Osmond, SA 5064, Australia.
Molecules. 2020 Feb 18;25(4):910. doi: 10.3390/molecules25040910.
Volatile phenols have been implicated as contributors to off-odors associated with taints from bushfire smoke and microbial spoilage. Various methods for the amelioration of off-odors have been evaluated, but to date, they have not included cyclodextrin (CD) polymers. In the current study, two CD polymers were prepared from β- and γ-CD, using hexamethylene diisocyanate (HDI) as a crosslinking agent. Adsorption tests were performed with four volatile phenols (guaiacol, 4-methylguaiacol, 4-ethylguaiacol and 4-ethylphenol) at concentrations up to 1 mg/L. The removal of volatile phenols by CD polymers achieved equilibrium almost instantly, with isotherm tests suggesting an adsorption capacity of 20.7 µg of volatile phenol per gram of polymer. Langmuir and Freundlich models were subsequently used to fit the data. In batch adsorption tests, the CD polymers achieved 45 to 77% removal of volatile phenols. Polymer reusability was also evaluated and was found to be excellent. A comparison between volatile phenol adsorption by CDs vs. CD polymers, determined using a novel four-phase headspace solid-phase microextraction (HS-SPME) method for gas chromatography-mass spectrometry (GC-MS), suggests CD polymers offer several advantages for use by the wine industry.
挥发性酚类化合物被认为是与丛林火灾烟雾和微生物腐败有关的异味的贡献物。已经评估了各种改善异味的方法，但迄今为止，它们还没有包括环糊精（CD）聚合物。在当前的研究中，使用六亚甲基二异氰酸酯（HDI）作为交联剂，从β-CD 和 γ-CD 制备了两种 CD 聚合物。用四种挥发性酚（愈创木酚、4-甲基愈创木酚、4-乙基愈创木酚和 4-乙基苯酚）在高达 1mg/L 的浓度下进行了吸附测试。CD 聚合物对挥发性酚类化合物的去除几乎瞬间达到平衡，等温线测试表明聚合物每克的吸附容量为 20.7µg 挥发性酚类化合物。随后使用朗缪尔和弗伦德利希模型拟合数据。在批量吸附试验中，CD 聚合物对挥发性酚类化合物的去除率达到 45%至 77%。还评估了聚合物的可重复使用性，结果发现其性能非常出色。使用新型四相顶空固相微萃取（HS-SPME）法与气相色谱-质谱联用（GC-MS）测定的 CD 与 CD 聚合物对挥发性酚类化合物的吸附比较表明，CD 聚合物为葡萄酒行业的应用提供了一些优势。
