花卉萃取添加於保養品中受到消費者的青睞，其中功效是否與標榜之花卉特性相符合，萃取添加濃度為關鍵要素之一。本研究以台灣本土種植之金盞花花卉蒸餾萃取之純露添加於精華液配方中，探討以成本為主要考量之產品設計是否可達到預期效果。總收案人數為60人，隨機分為三組；分別使用添加0%、12.5%、25%純露之精華液，介入措施為期四週，膚質檢測評估工具為CutometerR MPA 580多功能膚質水分檢測儀與VISIA高階數位膚質檢測儀，比較試驗前、後測組內差異以及三組的組間差異。分別針對皮膚表皮角質水分、斑點、皺紋、紋理、毛孔、紫外線斑、棕色斑、紅色區、紫質等九項膚質狀況進行檢測分析，實驗結果顯示連續四週使用精華液後，膚質狀況並未改善，三組試驗組也沒有顯現組間差異，結論低於25%以下的金盞花純露添加於精華液配方製品，功效未達顯著差異，僅以花卉天然香氣作為行銷廣告訴求之附加價值。

Skincare products added with flower extract are popular among consumers. Whether such a product’s effects are consistent with the properties of the flower whose extract is said to have been added to the product is determined by the extract concentration. In this study, Calendula officinalis hydrosol grown in Taiwan was added to an essence formula to discuss whether the cost-effective product design met the expected outcome. This study recruited 60 participants, who were randomly divided into three groups; the three groups each applied essences added with 0%, 12.5%, and 25% Calendula officinalis hydrosol. The intervention was conducted for four weeks, and the instruments used to determine the skin quality were the multifunctional skin moisture tester CutometerR MPA 580 and the high-quality digital skin quality tester VISIA. The pretest–posttest within group differences of and the between-group differences among the three groups were observed in the moisturizing, spots, wrinkles, texture, pores, UV spots, brown spots, red areas, and porphyrins of stratum corneum. The results revealed that, after using the essence for consecutive 4 weeks, the participants’ skin quality was not improved and that the between-group differences were nonsignificant. This study concluded that essences added with Calendula officinalis hydrosol with a concentration of 25% or lower did not have significant effects on the skin quality; instead, such a flower extract was added to products only for its natural fragrance so as to add value to products for the need of marketing and advertising.