零售未密封包裝的鮮榨 (現榨) 果汁，標榜不經過殺菌，可以保持原有的風味和營養素，深受消費者的喜愛，但其製作場所與產品衛生狀況仍有待加強。本研究之目的係以評估葡萄汁的揮發性成分、花青素組成與游離胺基酸組成之變化，以期建立鮮榨葡萄汁的品質指標。研究結果顯示，殺菁處理會稍微影響葡萄汁品質，使揮發性成分與花青素降低，但因殺菁處理會破壞果汁中酵素活性，在冷凍或冷藏儲存期間葡萄汁品質 (揮發性成分、花青素組成與游離胺基酸組成) 變化不大，所以適當的殺菁處理可以穩定葡萄汁之品質；而未殺菁葡萄汁揮發性成分1-hexanol於儲存期間會持續增加，而花青素含量會隨著冷藏儲存時間的增加而減少，但游離胺基酸組成變化不大，因此揮發性成分1-hexanol與花青素可作為鮮榨葡萄汁的品質指標。另花青素malvin chloride含量多寡，可以作為區分國內 (巨峰與黑后) 與義大利 (希哈與梅洛) 不同葡萄品種之依據；花青素malvidin 3-O-glucoside chloride含量多寡，可以作為區分黑后與美國康科德不同葡萄品種之依據；花青素peonidin 3–glucoside chloride與malvidin 3-O-glucoside chloride之含量多寡，可以作為區分黑后與巨峰葡萄品種之依據；而游離胺基酸組成以天門冬胺酸、丙胺酸、γ-胺基丁酸及精胺酸個別與脯胺酸之比值可作為區分為國產葡萄或進口葡萄之參考依據。

Retailed unsealed freshly squeezed fruit juice is preferable for the
consumers due to the flavor and nutrients that are maintained and not destroyed by pasteurization processes; however, there are sanitary issues for the processing area as well as the products. In this research,changes of volatile compounds, anthocyanin compositions and free amino acid
compositions in grape juice were investigated in hope to set up the
quality standards for freshly squeezed grape juice. Results showed that blanching would slightly affect the quality (lower volatile compounds and anthocyanins) of grape juice; however, since the enzyme activities were destroyed during the processes, changes in quality (volatile compounds, anthocyanin compositions and free amino acid compositions) during frozen or refrigeration were found minimal. Therefore, the proper blanching is useful to maintain the quality of grape juice. Volatile compound (1-hexanol) in unblanched grape juice increased and anthocyanin contents decreased during storage; however, changes in free amino acid composition were found minimal during storage. Therefore, volatile compound (1-hexanol) and anthocyanin contents can be served as the quality indicators for freshly squeezed grape juice. Moreover, malvin chloride can be
utilized to differentiate locally produced grape varieties (Kyoho and Black Queen) from Italian ones (Syrah and Merlot); malvidin 3-O-glucoside chloride contents can be used to differentiate Black Queen from American Concord. Furthermore, peonidin 3-glucoside chloride and malvidin 3-O-glucoside chloride can be utilized to distinguish grape varieties between Black Queen and Kyoho. On the other hand, ratios of aspartic acid, alanine, γ-aminobutyric acid and serine to proline can be used todifferentiate locally produced and imported grapes