金柑稀釋果汁與原汁貯藏品質之研究

Processing of Dilute Kumquat Juice and Storage Quality of Fresh Kumquat Juice (Fortunella margerita L.)

石正中(Jeng-Jung Shyr)

《宜蘭技術學報》 9期生物資源專輯 (2002/12) Pp. 27-32

https://doi.org/10.6179/nit.job.2002.09.13

摘要

黃熟之金柑果實以研磨式榨汁機榨取之果汁分析其糖度為12°Brix、酸度為1.6%、黏調度為600 centipoise、pH 3.07，以果膠酵素處理後加水調整酸度至0.5%並以白砂糖維持糖度12°Brix，後以蒸氣脫氣10分鐘後封罐後，再以蒸氣殺菌20分鐘後，冷卻即得金柑稀釋果汁。以此果汁進行官能品評試驗，結果顯示此果汁之甜味【適中】、酸味【適中】、苦味【微苦與有點苦之間】、香氣【適中】、色澤【有點好與好之間】、濃調度【有點稀與適中之間】、整體接受性【有點喜歡與喜歡之間】。貯藏過程中品質之變化採榨取後之原汁，經脫氣與殺菌等過程後，置於25°C與37°C下每月調查分析其色澤與香氣等品質因子之變化情形。結果顯示果汁在37°C下貯藏，色澤改變非常明顯，類胡蘿蔔素含量降低與非酵素性之褐化應是造成之原因，主要香氣物質limonene之含量略減且有梅納反應產物產生。

關鍵字

金柑稀釋果汁 ； 官能品評 ； 貯藏品質

並列摘要

Kumquat juice was extracted from matured kumquat fruits with yellow-orange color by ground in an automatic juice grinder. Total solids content, acidity, viscosity, and pH of the juice were 12 °Brix, 1.6%, 600 centipoise and 3.07 analyzed right after the juice was extracted. Tap water was added to adjust the acidity of pectinases treated kumquat juice to 0.5% level and also remained the total solids content by sugar addition. Following by 10 minutes steam exhausted, 20 minutes steam sterilization, and cooling processes, the kumquat dilute juice was made. Sensory analysis results showed that all the characteristics analyzed were close to the medium level. Extracted kumquat juice loaded in glass jars were stored at 25 and 37°C after exhausted and sterilization. Changes of color and volatiles were analyzed every month. A serious color degradation was found at 37°C and carotenoids decrease as well as non-enzymatic browning were possible reasons. Limonene content was slightly decreased and some Maillard reaction products were found.

並列關鍵字

kumquat dilute juice ； sensory evaluation ； storage quality