靜態與動態消費者型感官品評技術於臺灣特色茶感官特性之評估

臺灣特色茶感官品質的研究大多利用儀器分析、專家品茶師或訓練型品評員進行評估，但這些方式與一般消費者感受及偏好可能有所差異。利用消費者來進行評估，可以真實貼近消費者想法，且沒有高成本及需費時訓練的缺點。本研究目的是利用靜態與動態之消費者型感官品評技術評估7種臺灣特色熱泡及冷泡茶，包含消費者感官接受性及對茶之感官、概念及感受特性，以及評估9種感官特性在口中品飲之動態變化，並比較方法間之異同。本研究臺灣特色茶熱泡方式是以茶葉比水1:50的比例用沸水現泡5分鐘後現飲，而冷泡茶製備方式為用常溫水沖泡，放入4oC 6小時，在靜態描述分析選擇適合項目法及消費者接受與喜好性之評估於熱泡茶與冷泡茶試驗，分別招募109與108位消費者。動態描述分析時序選擇適合項目法與時序感覺支配法之評估皆為相同之品評員，招募63與64位消費者。本研究調查之臺灣消費者有喝茶習慣約有8成；喝茶頻率高低不會影響整體喜歡程度。臺灣消費者對熱泡茶的接受度稍高於冷泡茶。偏好文山包種茶、高山烏龍茶、凍頂烏龍茶、鐵觀音茶與東方美人茶等半發酵茶，而不喜歡碧螺春綠茶及日月潭紅茶。依據消費者對特色茶的整體喜歡程度，約3成為「有茶就喝」型之消費者、約4成為「半發酵茶高接受」型與約3成「鍾愛包種及烏龍茶」型的消費者；「半發酵茶高接受」型，完全不接受日月潭紅茶；「鍾愛包種及烏龍茶」型的消費者完全不接受碧螺春綠茶及日月潭紅茶，不喜歡東方美人茶。喜好性和接受性的趨勢相似，但實際品嚐時，消費者最喜歡文山包種茶，而無品嚐行為，消費者最不想喝的是文山包種茶。利用消費者型評估方式對臺灣特色茶感官特性進行評估，描述語確定為該茶感官特性的方法是該描述語被超過20%消費者所選擇為目標；消費者描述熱泡茶與冷泡茶感官特性，整體趨勢都十分接近，主要在外觀的描述不同但香氣、風味、口感及餘味的描述相近。在某些感官特性中，熱泡茶相對於冷泡茶會有較高被消費者選擇的比例。消費者認為熱泡之碧螺春綠茶、文山包種茶、高山烏龍茶和凍頂烏龍茶感官特性相近，而冷泡時，碧螺春綠茶有明顯的青草香氣、苦味、澀味、酸味及苦餘味的特性；與文山包種茶、高山烏龍茶與凍頂烏龍茶具有清香氣、茶香氣、茶菁味、回甘感、回香感與清爽感等特性不同。鐵觀音茶與東方美人茶熱泡茶相近，具花香、碳焙味及發酵茶味等特性，而日月潭紅茶熱泡茶具有蜜糖香氣、苦味、澀味及刺激感的特性；在冷泡上，鐵觀音茶、東方美人茶與日月潭紅茶特性相近。臺灣消費者不喜歡茶中具有苦味、酸味、澀味及刺激感等特性。消費者對於碧螺春綠茶熱泡茶有明顯的刮胃感；文山包種茶、高山烏龍茶與凍頂烏龍茶之熱泡茶及冷泡茶認為是舒服的，有清香感、自然溫和與解膩感；對鐵觀音茶熱泡茶認為優質，有韻味悠長的感受，但冷泡茶感受不舒服，太濃厚強烈；東方美人茶熱泡茶是具有文化的，有明顯的濃厚強烈與韻味悠長之感受，但冷泡茶消費者感受不舒服，有刮胃感；日月潭紅茶之熱泡及冷泡茶都感受不舒服，但冷泡茶有特別的感受，有濃厚強烈及刮胃感。時序選擇適合項目法顯示熱泡茶在口中品飲之風味變化為苦味、酸味、花香味與刺激感；其次是甜味、澀味、茶菁味與回甘感，而冷泡茶之變化為苦味、澀味與茶菁味，其次為甜味、碳焙味與回甘感；有些描述語在口中變化大但感受不明顯。時序感覺支配法為了解品嚐過程支配感覺的感官描述順序或變化。熱泡茶支配風味之感覺為苦味、酸味、茶菁味與回甘感，其次為澀味、碳焙味與刺激感，而冷泡茶酸味與回甘感，其次為苦味、澀味與花香味。臺灣特色茶感官特性使用不同感官評估方法評估且進行分類結果都具有高度正相關性，動態感官評估方法比靜態感官評估方法更能區分其差異，其中時序選擇適合項目法又比時序感覺支配法更能區分其差異。

關鍵字

感官品評；臺灣茶；消費者測試；時序選擇適合項目法；時序感覺支配法

並列摘要

The study of sensory quality of Taiwan special tea was evaluated by instrumental analysis, expert panel and trained-well sensory panels in the past. However, these methods may be different from the general consumer perceptions and preferences. Using consumer panels to evaluate the sensory properties can be realistically close to the consumer's ideas and avoid the disadvantages of high cost and time-consuming training in the evaluation process. The purpose of this study was to evaluate seven types of Taiwanese special teas brewing with hot and cold water using static and dynamic consumer-type sensory evaluation techniques, including consumer sensory acceptance and sensory, conceptual and cognitive characteristics as well as the dynamic changes in the taste of the mouth for nine sensory characteristics. In addition, we also sought to understand the similarities and differences between the methods. In this study, the hot tea was brewed with the ratio of tea to water 1:50, which is boiled in boiling water for 5 minutes. The preparation method of cold tea is brewed with normal temperature water and placed in 4oC for 6 hours. We recruited109 and 108 consumers in hot tea and cold tea experiments for static sensory evaluation such as sensory acceptance and descriptive test of check-all-that-apply method. The dynamic methods, temporal check-al-that-apply method and temporal dominance of sensation method were respectively recruited by 63 and 64 consumers. Basically, these consumers have to finish the evaluation of the two methods. Our survey found that 80% of the panelists in this study have to drink Chinese tea habits and the frequency of tea consumption does not affect the overall preference. Taiwanese consumers get a slightly higher acceptance of hot tea than cold tea. They preferred semi-fermented teas such as Wen Shan Paochung tea, Alpine Oolong tea, Dongding Oolong tea, Iron Goddess tea and Oriental Beauty Tea, but not Biluchun Green Tea and Sun Moon Lake Black Tea. According to the consumer's overall preference for specialty tea, they can be classified three types. 30% consumers are “Love Tea” type, 40% are “High Preference in semi-fermented tea” and 30% are “Only Paochung tea, and Oolong tea” type. The consumers of “High Preference in semi-fermented tea” type do not accept Sun Moon Lake black tea at all, and the type of Only Paochung tea, and Oolong tea” do not accept Biluochun Green Tea and Sun Moon Lake Black Tea at all, and do not like Oriental Beauty Tea tea. The trend of sensory acceptance and preference is similar. However, it is interested that consumers ranked first for Paochung tea at the actual tasting but Paochung tea was ranked last in no-tasting behavior. While consumer-based methods were used to evaluate the sensory characteristics of Taiwanese specialty tea, the descriptive attributes are determined to be the sensory characteristic of the tea that was selected by more than 20% of consumers in this test. Overall attributes which described by consumers are very similar in the hot tea and cold tea. The primary difference in the sensory attributes between hot tea and cold tea is the appearance attributes. Consumers have a higher proportion choice in certain organoleptic properties of hot tea than in cold tea. Consumers perceived that the sensory characteristics of Biluochun tea, Wenshan Paochung Tea, Alpine Oolong tea and Dongding Oolong tea are similar in hot tea but Biluochun tea brewed with cold water has obvious characteristics of grassy aroma, bitterness, astringency, sourness and bitter aftertaste and is significantly different sensory properties with Wenshan Paochung Tea, Alpine Oolong tea and Dongding Oolong tea which have sensory characteristics such as fresh aroma, tea aroma, fresh tea leaf aroma, sense turning to sweet, sense turning to good smell and refreshments. The sensory characteristics in hot tea for Iron Goddess tea and Oriental Beauty tea are comparable with floral aroma, roasted flavor and fermented tea flavor and are honey aroma, bitterness, astringency and sharp mouthfeel for Sun Moon Lake black tea. For cold tea, the sensory properties among three teas are very close. Taiwanese consumers dislike the sensory characteristics of bitterness, sourness, astringency and sharp mouthfeel in tea. Consumers tasted hot tea in Biluochun green tea and had significant uncomfortable sensation in the stomach. Consumers feel comfortable, fresh aroma, natural and cut the grease of a cup of tea while they both tasted the hot and cold tea for Wenshan Paochung Tea, Alpine Oolong tea and Dongding Oolong tea. Consumers tasted hot tea for Iron Goodness tea considered high quality and had a long-lasting feeling in the mouth but for cold tea felt uncomfortable and too strong flavor. The hot tea of the Oriental beauty tea let consumers feel very culture with a strong and long-lasting feeling but consumers feel uncomfortable and have an uncomfortable sensation in the stomach for cold tea. The hot tea and cold tea for the Sun Moon Lake black tea are uncomfortable but there is a special feeling with the strong flavor and the uncomfortable sensation in the stomach. Results of temporal check-all-that-apply method demonstrated the primary change of sensory perceptions in the mouth for the hot tea is bitterness, sourness, floral aroma and sharp mouthfeel and the secondary change is sweetness, astringency, fresh tea flavor and sense turning to sweet. The main change in the mouth for the cold tea is bitterness, astringency and fresh tea flavor along with sweetness, roasted flavor and sense turning to sweet. Some of these attributes in the mouth could vary greatly, but the perception is not apparent. Temporal dominance of sensation is to understand the orderly change of sensory description in the mouth. The dominance sensation of hot tea is primarily bitterness, sourness, fresh tea flavor and sense turning to sweet, along with astringency, roasted flavor and sharp mouthfeel and it is sourness and sense turning to sweet, along with bitterness, astringency and floral flavor in cold tea. There is positively correlated with different sensory evaluation methods in the understanding the sensory properties and classifications of Taiwan’s special tea. The dynamic sensory evaluation method can distinguish the difference more than the static sensory evaluation method. In addition, temporal check-all-that-apply method in this study is best to distinguish the differences in the changes of sensory perceptions in the mouth than the method of temporal dominance of sensations using consumer panels.