Studies on Candied Fruits Processing

• Main Authors: Chen Yan Fu, 陳彥甫
• Other Authors: 陳雪娥
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/61093129202169244134

碩士 === 輔仁大學 === 食品科學系 === 95 === This paper was divided into two parts. The first part reviewed the traditional candied fruit processing technology, improving methods to shorten processing time and the low-sugar candied fruit processing technology. Traditional candied fruits processing involved 3 main procedures: pretreatment, syruping and the drying treatment of which the syruping and drying treatment account for more than 2/3 of the total processing time. The vacuum-syruping technology is an effective, practical, hygienic process worthy of popularizing. It shortens the syruping time over a half times compared with that of the traditional technology. The drying process is the final step for candied fruits, and will influence the quality as well. Traditional drying technology usually used hot-air to dehydrate the products for reaching the final water activity, and required at least 10-12 hours. Moreover hot-air drying is not suitable for all candied vegetables or fruits. Therefore vacuum, microwave and microwave-air drying technology have been developed and applied to various vegetables and fruits . And the use of these technologies can attain the products with good quality in the appearance , the color and the taste. Candied fruit is a high-sugar, high-caloric food which gradually could not be accepted by consumers who care about their health. Producing low-sugar candied fruit is a market trend, but the low-sugar content will reduce bacteriological stability and the shelf life of products. Therefore, the application of the low-caloric sweeteners and preservatives for low sugar candied fruit processing has been intensively studied. Aspartame, a popular sweetener, is usually used instead of sucrose in low-sugar candied fruit processing. Sorbic acid and benzoic acid are commonly applied as preservatives. The addition of chitosan and propolis, which are natural preservatives, could prolong the shelf life of the products. KOP/PE/EVA Package filled with the nitrogen could keep the quality of candied fruits for up to 4 months. It was also satisfactory with γ- ray sterilize for prolonging the quality of low-sugar candied fruit. The second part is experimental study. The cherry tomato candied fruit processed by the 2 times continuous syruping technology could shorten the process time to 6-10 hours compared with the traditional one. The processing conditions for high-sugar candied fruit with better sensory properties were hot-water peeling, 2.5% citric acid added, drying time 15 hours at 60±5℃and air velocity 1200 L/hr. The processing conditions for low-sugar candied fruit with polydextrose substitute 50% sucrose were hot-water peeling, 1.5% citric acid added, drying time 18 hours at 60±5℃and air velocity 1200 L/hr. Furthermore, different cultivates of cherry tomato were processed to high-sugar and reduced-sugar candied fruit. The results showed that the overall sensory quality of products was no significantly different . It implied that above mentioned processing conditions could be applied in different cultivates of cherry tomato.