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1.
The anthocyanin composition of rose wine made from cv. Öküzgözü, a variety of grape native to Turkey, and the effect of maceration time (3, 6, 12, 18, or 24 h) on the anthocyanin content of the wine have been investigated. High-performance liquid chromatography with diode-array detection (HPLC-DAD) and mass spectrometry (MS) were used for anthocyanin analysis. Thirteen different anthocyanins, including five glucosides, five acetyl glucosides, and three coumaroyl glucosides were identified and quantified. It was found that an important characteristic of Öküzgözü rose wine was the presence of a large amount of malvidin-3-glucoside and its acylated esters. The total anthocyanin content of the wine increased with increasing maceration time. On the basis of sensory analysis, the most preferred wine was that produced with 3-h maceration, because of its better color and general flavor attributes.  相似文献   
2.
《Comptes Rendus Chimie》2014,17(3):187-196
The growing demand for plant-based products in the food, cosmetics and pharmaceutical industry leads to the need for a systematic process and equipment-design for the potentially applicable extraction techniques. Therefore, in this article, the classification of plant-based raw materials according to their characteristics is discussed. Furthermore, physicochemical modelling via distributed plug flow approach is applied and its possible fields of application are examined. Here, especially the extraction of water from the plant-based raw material as well as the entailed effects on the equilibrium and the mass transport kinetics are concerned. In addition to that, an evaluation method for the examined and generally available equipment through spider diagram is proposed. The relation to the initially argued botanic systems is discussed in particular. The extraction of vanillin from vanilla beans serves as exemplary system for this.  相似文献   
3.
本文首次报道用离析方法研究湖北省新洲县的被子植物化石木材的情况.实验证明,经该方法处理后的木化石、导管、木射线、纤维等清晰可见,这对化石木材的研究是有意义的,并提供了一种新的辅助手段.  相似文献   
4.
导数分光光度法测定毒饵中的敌鼠钠   总被引:2,自引:0,他引:2  
用紫外二阶导数分光光度法测定毒饵中敌鼠钠含量。当样品中含有0.4g·L-1、2g·L-1敌鼠钠时平均回收率为96.8%。标准曲线范围为1~5mg·L-1,相关系数为0.9998,相对标准偏差为0.6%~2.2%,检出限为0.15mg·L-1。  相似文献   
5.
桑皮的微生物脱胶制浆   总被引:1,自引:0,他引:1  
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6.
Maritime pine sawdust, a by-product from industry of wood transformation, has been investigated as a potential source of polyphenols which were extracted by ultrasound-assisted maceration (UAM). UAM was optimized for enhancing extraction efficiency of polyphenols and reducing time-consuming. In a first time, a preliminary study was carried out to optimize the solid/liquid ratio (6 g of dry material per mL) and the particle size (0.26 cm2) by conventional maceration (CVM). Under these conditions, the optimum conditions for polyphenols extraction by UAM, obtained by response surface methodology, were 0.67 W/cm2 for the ultrasonic intensity (UI), 40 °C for the processing temperature (T) and 43 min for the sonication time (t). UAM was compared with CVM, the results showed that the quantity of polyphenols was improved by 40% (342.4 and 233.5 mg of catechin equivalent per 100 g of dry basis, respectively for UAM and CVM). A multistage cross-current extraction procedure allowed evaluating the real impact of UAM on the solid–liquid extraction enhancement. The potential industrialization of this procedure was implemented through a transition from a lab sonicated reactor (3 L) to a large scale one with 30 L volume.  相似文献   
7.
《Arabian Journal of Chemistry》2020,13(12):8909-8919
Ghee is a dairy product widely consumed in India, north-Africa, and Middle East countries, having beneficial pharmacological effects. This study aims to characterize the effects of aromatic plants addition (rosemary and clove) on the nutritional, volatile and oxidative profile of cow ghee and to evaluate the effect of flavored ghee on the fibroblasts migration during wound healing in vitro assay. Two flavored ghee products were obtained by adding clove (CG) and rosemary (RG) as aromatic plants through maceration in cattle traditional ghee (BT). It was revealed that enriched ghee samples had significantly lower peroxide values (6.76 and 6.80 meqO2 /kg) compared to control samples (8.20 meqO2 /kg). Moreover, the addition of rosemary and clove change the volatile profile, and increased the retinol levels of ghee (BT: 1.3 mg/kg; CG: 1.9 mg/kg; and RG: 3.05 mg/kg). Liquid-chromatography analyses revealed the presence of targeted phenolic compounds such as carnosic acid, rutin and gallic acid in CG and RG, showing thus, the transfer of polyphenols from aromatic plants into the ghee matrix. On the other hand, the fatty acid composition of ghee remained unchanged. The major components of the prepared ghee samples contributed to rising significantly the human fibroblast migration in wound healing in vitro assay. The results obtained underline that the flavored ghee samples could improve skin regeneration, making them potentials therapeutic ingredients in skincare formulations.  相似文献   
8.
The efficiency of conventional and ultrasound-assisted maceration was investigated in comparison to reduce the bitterness of green walnuts. Conventional maceration was studied at room temperature for 6, 8 and 10 days while ultrasound-assisted maceration (20 kHz, %100 of amplitude) was performed at 36 °C for 6, 8, 10, 12, and 14 h. Phenolic content and antioxidant activity of green walnuts were decreased by reduction of bitterness. Phenolic content and antioxidant activity of green walnut jams prepared from debittered green walnuts by ultrasound-assisted maceration were higher than those of conventional maceration excluding ellagic acid only. Based on findings of sensory analyses, bitterness level was similar in green walnut jams prepared by ultrasound-assisted maceration for 12 h and conventional maceration for 6 days. On the other hand, green walnut jams processed by ultrasound-assisted maceration for 12 h led to the highest general acceptance. It was concluded that ultrasound-assisted maceration may provide better nutritional and sensory quality in green walnut jam. In addition, the time required for reduction of bitterness may be shortened from days to hours by ultrasound-assisted maceration.  相似文献   
9.
《Ultrasonics sonochemistry》2014,21(3):1030-1034
Products from plant raw materials gain increasing importance in food-, cosmetics and pharmaceutical industry. By way of contrast, due to lack of detailed physico-chemical fundamentals, existing production processes are economically not optimal designed. This leads to a need for deeper understanding of the processes and furthermore a systematic process and equipment design for the potentially applicable extraction techniques.Using the example of polyphenol extraction from black tea (Kenya), the conventional and ultrasound assisted extractions are investigated. Here, the state of the art as well as a comparison between the two techniques is in focus. Especially, resulting quasi-equilibria and mass transport kinetics serves as a criteria. The physico-chemical background is discussed taking particle size distributions and scanning electron microscope (SEM) measurements into account. Conclusively, process alternatives are projected and discussed. Hence, the present study makes influences of ultrasound technique on physico-chemical characteristics during extraction a subject of discussion.  相似文献   
10.
王霞  张祥志  陈素兰 《光谱实验室》2009,26(6):1445-1448
采用醋酸缓冲溶液对固体废物样品进行浸提,经硝酸-盐酸消解后,ICP-AES测定消解液中的钡,铍,镉,铬,铜,镍,铅和锌。本方法具有检出限低、再现性好、分析效率高等优点,适用于固体废物浸出毒性的测定。  相似文献   
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