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41.
The effect of juice extraction conditions on the quality of haskap berries (Lonicera caerulea L.) dried at different temperatures (60, 100, and 140°C) was investigated. The conventional juice extraction (process A) consisted of a two-press process, where thawed berries were pressed, and osmotic treatment was applied before pressing again. This was compared with a modified extraction (process B), which applied osmotic treatment during fruit thawing and only one press was used for extraction. The quality parameters investigated included moisture content, pressed berry yield, extraction loss, drying yield, total anthocyanin content (TAC), vitamin C content, and the rehydration characteristics of the final dried berries. Pressing the berries to 70% juice yield resulted in a higher pressed berry yield and better physicochemical quality in the pressed product. The yield was 26.39 and 28.92% in the conventional and modified extraction, with moisture contents of 70.32 and 77.75%, respectively. The TACs of pressed berries from extraction processes A and B were 24.62 and 33.03?mg C-3-G g?1 DW and the vitamin C contents were 14.14 and 36.18?mg/100?g, respectively. Drying at 60°C until 25% moisture content was better than at higher temperatures, resulting in a better quality dried product. It revealed drying yields of 45.32 and 52.75%, TACs of 4.00 and 4.30?mg C-3-G g?1 DW, vitamin C contents of 2.97 and 4.91?mg /100?g, and rehydration ratios of 2.22 and 2.37 from processes A and B, respectively. Process B with the one-step extraction is recommended for higher pressed berry yield, higher drying yield, and enhanced quality of the pressed and dried products. It is also a more efficient process, in terms of time, cost, and energy.  相似文献   
42.
考察槐米提取液的体外抗氧化、美白能力及加入乳液化妆品后的保湿、美白功效。实验结果表明:槐米提取液具有一定的体外抗氧化活性,与传统的抗氧化产品V_C相比,其对DPPH的清除效果好于V_C,对羟基自由基的清除率以及还原能力与V_C接近;0.3 g/L的槐米提取液对酪氨酸酶的抑制率为60.33%;添加槐米提取液的乳液化妆品能有效提高其保湿性,增强其美白功效,对皮肤安全、无刺激。  相似文献   
43.
王雁南  鞠美庭  李维尊  李倩 《化工进展》2013,32(2):470-474,480
考察了经过NaOH活化的结缕草在1-烯丙基-3-甲基咪唑氯盐(AMIMCl)离子液体中的溶解再生性能。通过木质纤维素成分分析表明,经不同浓度NaOH活化的结缕草的纤维素含量显著提高,并且结构遭到一定的破坏,提高了原料与离子液体的反应活性,并且以10%的NaOH为最优比例。经过FT IR、XRD以及NMR谱图表征了AMIMCl、再生AMIMCl以及提取物的化学结构,发现AMIMCl对NaOH活化的结缕草的提取效果较好,纤维素产率高,环境友好,不产生副产物,同时离子液体经再生后可高效循环利用。  相似文献   
44.
This article presents multiple potential uses of the Yakushima native cedar (Cryptomeria japonica), known in Japan as the Yaku-sugi tree. The Yaku-sugi was divided into four parts: leaves, branches with leaves, branches, and stems. We obtained the essential oil, hydrosol, distillation residue, and distillation wastewater from the trees. Essential oil and hydrosol were determined to be volatile organic compounds. All samples were screened for the following bioactivities: antioxidative, antibacterial, and anti-melanogenesis activities. Freeze-dried distillation residue was tested to assess whether it had a deodorizing effect. The main component of the leaf essential oil was found to be monoterpenes. In contrast, the stem essential oil mainly contained sesquiterpenes. In terms of bioactivities, the leaf essential oil showed antibacterial activity and the stem essential oil showed anti-melanogenesis activity. Distillation residue and wastewater showed many activities, including antioxidant, antibacterial, and anti-melanogenesis activities. Moreover, the residue had a deodorizing effect against ammonia.  相似文献   
45.
优化芦丁提取纯化工艺。用T型关联度对芦丁提取纯化工艺进行了研究。根据芦丁得率的关联度结果,各因素相关度大小为:X3〉X4〉X6〉X5〉X2〉X1,最佳工艺为95℃下杀酶40min,除胶水温度90℃,除胶水量(V/w),渗漉pH11.0,酸沉pH3~4,收率22.3%,含量94.2%。可将T型关联度分析法用于芦丁提取纯化工艺为工业化生产提供实验依据。  相似文献   
46.
An efficient microwave-assisted extraction (MAE) technique has been developed to recover chlorogenic acid from flower buds of Lonicera japonica Thunb. The yield of chlorogenic acid rapidly reached 6.14% within 5 min under the optimal MAE conditions, i.e. 50% ethanol as extraction solvent, 1:10 (w/v) of the solid/liquid ratio and 60 °C of extraction temperature. The MAE showed obvious advantages in terms of short duration and high efficiency to recover chlorogenic acid from raw plant materials in comparison with conventional heat-reflux extraction. The mechanism of the enhanced extraction by microwave assistance was discussed by observing cell destruction of plant material after MAE treatment by scanning electron microscopy. The results showed that the plant materials were significantly destroyed due to the cell rupture after MAE treatment.  相似文献   
47.
超声波提取山茶花红色素的初步工艺研究   总被引:1,自引:0,他引:1  
尹彩萍  张应烙  叶上升 《广州化工》2010,38(7):92-93,106
利用超声波技术提取山茶花红色素,通过超声波提取时间、超声波功率、提取温度、料液比、提取次数等单因素实验得到得到山茶花红色素超声波提取的工艺参数为:提取时间40min,提取功率500W,料液比1:12(g/mL),提取温度40℃,提取次数为3次。  相似文献   
48.
本研究从连云港海泥中筛选产普鲁兰酶菌株,利用形态学、生理生化特征、基因序列(16S rRNA和 gyrB)进行分析鉴定。利用产酶菌株发酵制备普鲁兰酶,初步纯化后分析其酶学性质。利用该普鲁兰酶粗提物对海带多糖进行水解,并对其水解产物进行抗氧化活性分析。结果表明:筛选得到一株产普鲁兰酶的巨大芽孢杆菌P6(Bacillus megaterium),经发酵纯化后普鲁兰酶比活力为62.3 U/mg,分子量约为43 kDa。该酶的最适反应温度为45 ℃,最适pH为6.5,在温度40 ℃下保温5 h,相对残余酶活达95%以上,而60 ℃下保温1 h,酶全部失活。在pH6~7.5之间保温12 h后,该酶仍有40%以上的相对残余酶活。DPPH和·OH自由基清除实验表明:海带多糖经普鲁兰酶水解后抗氧化活性显著增强(p<0.05),为普鲁兰酶在食品工业中的应用研究提供了新的方向。  相似文献   
49.
50.
对北方大穗型超级杂交粳稻辽优3072进行了产量结构和灌浆特性的研究。结果表明:辽优3072在产量结构上表现出了较强的杂交优势,比对照辽粳294增产明显。辽优3072在灌浆上的特点为穗上、中、下各部间干物质充实及灌浆速率差异较小:穗下部灌浆启动早,后期灌浆速率大;整穗表现出较强的持续灌浆能力。辽优3072良好的籽粒灌浆特性是其在产量上表现出超高产的生理基础之一。同时探讨了利用水稻杂交优势选育具有特异灌浆特性的杂交组合的育种思路以及在北方冷凉稻区推广大穗型超级杂交粳稻品种的可能性。  相似文献   
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