碩士 / 國立嘉義大學 / 食品科學系研究所 / 98 / In this study, persimmon leaves and persimmon are raw materials and the extracts of them are used to be a natural preservative to prolong the shelf life of shrimps. Further persimmon leaves and persimmon extracts are divided into different fractions by XAD column and determine their antibacterial ability and composition. Persimmon leaves and persimmon get from bull heart persimmon (Diospyros kaki L. cv. Bull heart) as raw materials. The extracts of persimmon leaves and persimmon are extracted by 90℃ and 25℃, respectively. Then the shrimps are dipped in the 500ppm total phenol concentration persimmon leaves or persimmon extracts by vacuum or atmosphere for 20 minutes or 60 minutes. Then take the shrimps out of the extracts and store at -20 ℃ or 4 ℃. Examination pH, volatile basic nitrogen (VBN), histamine content, color change (L. a. b.), texture profile analysis (TPA) and aerobic plate count as the indicator of shelf life of the shrimps once two days. No addition of preservatives as the blank group, addition of the commercial preservatives with the 500ppm solution of sodium hydrogen sulfite as the control group. The results show that after three days at 4℃, the pH value increase significantly, VBN has reached the limit value (25mg/100g), the springiness, and chewiness of shrimps tissue significantly decrease, the appearance also cause obvious melanosis, L value decrease, and the aerobic plate count are also exceed the limit, 3×106 CFU/g for the blank group. The shrimps soak in the extracts for 20 minutes by vacuum and storage at 4 ℃, the pH value significant up, L values, texture significantly decrease equal to the commercially preservative sodium hydrogen sulfite after five days. As the groups soak into the persimmon leaves and persimmon extracts, the VBN values are lower than the group soak into the sodium hydrogen sulfite. Indicating persimmon leaves and persimmon extracts can inhibit the growth of spoilage bacteria and amines bacteria, and be effectively extend the shelf life. Further the extracts of persimmon leaves and persimmon are separated by XAD-16 and XAD-7 column, respectively, then elute with six different concentrations of methanol solutions, which can obtain six different fractions to determination the antimicrobial activity and analysis high-performance liquid chromatography (HPLC). The results show that the PLF3 fraction of persimmon leaves (70% H2O: 30% MeOH) and PF5 fraction of persimmon (40% H2O: 60% MeOH) with excellence inhibitory effect on Escherichia coli BCRC 10675, Bacillus subtilis BCRC 10255 and Staphylococcus aureus BCRC 10451, but no significant inhibitory effect on Salmonella Typhimurium BCRC 12947. The HPLC analysis show that the gallic acid, protocatechuic acid, p-hydroxybenzoic acid, chlorogenic acid, rutin, kaempferol, (-)-epicatechin, ferulic acid, myricetin and other active ingredients in the fractions.
| Identifer | oai:union.ndltd.org:TW/098NCYU5253009 |
| Date | January 2010 |
| Creators | Hui-Ju Chang, 張惠茹 |
| Contributors | Jan-Jeng Huang, 黃健政 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 139 |
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