Açaí berry is the fruit of an Amazonian palm tree and rich in anthocyanins (ACNs). Scientific studies have proven the health benefits of açaí berry and declared this fruit as “super fruit”. ACNs have high antioxidant activities, but they are unstable and can easily deteriorate during food processing. In order to protect ACNs and increase their applicability, food-grade water-in-oil (W/O) emulsions were successfully formulated with different concentrations of açaí berry extracts (AEs). The formulated W/O nanoemulsions were relatively stable, with no phase separation after 30 days of storage. The average droplet size varied between 146.8 and 814.8 nm, with higher values corresponding to samples without AEs. All W/O nanoemulsion samples exhibited antioxidant activity and high retention rates of polyphenols after 30 days of storage. ACN retention followed first-order kinetics, with high protection of ACNs observed in emulsified samples. 2% AE encapsulated in a 30 wt% W/O nanoemulsion had an estimated half-life of 385 days. The results indicate that stable nanoemulsion systems with high ACN protection can be produced with possible applications in the food and pharmaceutical industries.

Açaí浆果是亚马逊棕榈树的果实，富含花青素（ACN）。科学研究证明了巴西莓的健康益处，并宣布这种水果为“超级水果”。乙腈具有很高的抗氧化活性，但不稳定，在食品加工过程中容易变质。为了保护ACN并提高其适用性，成功地用不同浓度的巴西莓提取物（AE）配制了食品级油包水（W / O）乳液。配制的W / O纳米乳液相对稳定，在储存30天后没有相分离。平均液滴尺寸在146.8和814.8 nm之间变化，较高的值对应于没有AE的样品。储存30天后，所有W / O纳米乳液样品均表现出抗氧化活性和多酚的高保留率。ACN保留遵循一级动力学，在乳化样品中观察到对ACN的高度保护。封装在30 wt％W / O纳米乳液中的2％AE的估计半衰期为385天。结果表明，可以在食品和制药行业中应用，生产出具有高ACN保护性能的稳定纳米乳液体系。