Department of Food and Dairy Sciences and Technology, Damanhour University, Damanhour 22516, Egypt.
Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2-Pad. Besta, 42100 Reggio Emilia, Italy.
Molecules. 2022 Oct 12;27(20):6843. doi: 10.3390/molecules27206843.
Yogurt is considered one of the most popular and healthy dairy products, and has been exploited as a delivery matrix for phenolic compounds. In this study, coffee powder was added to yogurt as a functional ingredient to produce coffee-fortified yogurt. Total phenolic compounds, antioxidant activity and individual hydroxycinnamic acids have been identified and quantified through mass spectrometry. The results from coffee-fortified yogurt were compared with fermented coffee and plain yogurt. Coffee-fortified yogurt had higher total phenolic content and antioxidant activity compared to plain yogurt. However, the total phenolic compounds found in coffee-fortified yogurt represented only 38.9% of the original content in coffee. Caffeoylquinic acids were the most abundant phenolic compounds in coffee. Fermented coffee and coffee-fortified yogurt displayed lower amounts of individual phenolic compounds with respect to coffee (69.8% and 52.4% of recovery, respectively). A protective effect of the yogurt matrix on total and individual coffee phenolic compounds has been observed after in vitro digestion, resulting in a higher bioaccessibility in comparison with digested fermented coffee. Moreover, coffee-fortified yogurt showed the highest antioxidant values after digestion. These findings clearly demonstrate that coffee-fortified yogurt can be considered a significant source of bioaccessible hydroxycinnamic acids, besides its health benefits as a fermented dairy product.
酸奶被认为是最受欢迎和最健康的乳制品之一，并被用作酚类化合物的递送基质。在本研究中，咖啡粉被添加到酸奶中作为功能性成分，以生产含咖啡的酸奶。通过质谱法鉴定和定量了总酚类化合物、抗氧化活性和个别羟基肉桂酸。将含咖啡的酸奶的结果与发酵咖啡和普通酸奶进行了比较。与普通酸奶相比，含咖啡的酸奶具有更高的总酚含量和抗氧化活性。然而，含咖啡的酸奶中发现的总酚化合物仅占咖啡中原始含量的 38.9%。咖啡酰奎宁酸是咖啡中最丰富的酚类化合物。发酵咖啡和含咖啡的酸奶中与咖啡相比，个别酚类化合物的含量较低（分别为 69.8%和 52.4%的回收率）。体外消化后观察到酸奶基质对总酚和个别咖啡酚类化合物具有保护作用，与消化后的发酵咖啡相比，生物利用度更高。此外，消化后的含咖啡酸奶显示出最高的抗氧化值。这些发现清楚地表明，含咖啡的酸奶除了作为发酵乳制品的健康益处外，还可以被认为是生物可利用的羟基肉桂酸的重要来源。
