Abstract This study compared the capacity of propolis extract (PE) and thyme waste extract (TWE) to prevent the oxidation of oil in water (O/W) emulsion, as well as their impact on emulsion apparent viscosity (AV) in the presence of wheat germ and almond oils as lipid phase. For this, central composite design (CCD) and principal component analysis (PCA) were performed. Oxidation process was monitored by evaluating the formation of primary and secondary lipid oxidation products, at the same time the AV behavior was determined evaluating consistency index and flow behavior index. The results revealed that the increase of PE% and TWE% decreases TBARS (Thiobarbituric Acid Reactive Substances) and hydroperoxides formation. Viscosity increases with the rise of TWE% over (0.04%), whereas lower concentrations of PE% decreases it. Those results have been confirmed in the PCA analysis. TWE showed higher resistance to oxidation, although PE was more effective as antioxidant than TWE.

中文翻译：

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O/W 乳液中的天然抗氧化剂

摘要 本研究比较了蜂胶提取物 (PE) 和百里香废料提取物 (TWE) 防止水包油 (O/W) 乳液氧化的能力，以及它们对乳液表观粘度 (AV) 的影响。小麦胚芽油和杏仁油作为脂相。为此，进行了中心复合设计（CCD）和主成分分析（PCA）。通过评估初级和次级脂质氧化产物的形成来监测氧化过程，同时通过评估一致性指数和流动行为指数来确定AV行为。结果表明，PE% 和 TWE% 的增加减少了 TBARS（硫代巴比妥酸反应性物质）和氢过氧化物的形成。粘度随着 TWE% 的增加而增加 (0.04%)，而较低浓度的 PE% 会降低粘度。这些结果已在 PCA 分析中得到证实。TWE 表现出更高的抗氧化性，尽管 PE 作为抗氧化剂比 TWE 更有效。