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排序方式: 共有930条查询结果,搜索用时 15 毫秒
61.
The potential utilization of buttermilk from an industrial source was studied in this research, focusing primarily on its composition and use as ingredient in oil-in-water emulsions. Buttermilk contained not only large amounts of caseins and whey proteins, but also material derived from the natural milk fat globule membrane (MFGM). Emulsions made with soybean oil (10% w/w) and buttermilk were stable with a low concentration (about 1% w/w) of buttermilk solids. MFGM-proteins and skim milk proteins did not seem to compete for adsorption at the emulsion interface. The protein adsorbed at the interface was present in an aggregated form and gave a maximum surface coverage of about 8 mg/m2 . 相似文献
62.
This study proposes a method for preparation of transparent emulsions for cosmetic applications. The continuous phase in oil-in-water emulsions consisted of both water and several polyols in order to equalize the refractive indices of the two phases. Sorbitol , glycerol and mannitol were the main polyols used in the adequate concentration and isopropyl myristate was the oil phase. Stabilities of a few days in 60°C incubation and a few months on the shelf were obtained.
Combinations of triethanolamine oleate together with sorbitan esters and ethoxylated sorbitan esters were found to improve the emulsion stability.
The optimal water concentration was checked by spectrophotometer measurements at 660 nm in order to achieve best transparency.
In conclusion, it was demonstrated that relatively stable transparent macroemulsions can be prepared by equalizing the refractive indices of the two phases composing the emulsion.
Application des macroémulsions transparentes a la cosmétique 相似文献
Combinations of triethanolamine oleate together with sorbitan esters and ethoxylated sorbitan esters were found to improve the emulsion stability.
The optimal water concentration was checked by spectrophotometer measurements at 660 nm in order to achieve best transparency.
In conclusion, it was demonstrated that relatively stable transparent macroemulsions can be prepared by equalizing the refractive indices of the two phases composing the emulsion.
Application des macroémulsions transparentes a la cosmétique 相似文献
63.
Sofia Melchior Sonia Calligaris Marilena Marino Francesca D’Este Giorgio Honsell Maria Cristina Nicoli Nadia Innocente 《International Journal of Food Science & Technology》2022,57(5):3106-3115
This research aimed at studying the potential use of monoglyceride (MG) structured emulsions (MSEs) as delivery and protective systems for probiotic bacteria in Ricotta cheese. To this purpose, a low-fat commercial Ricotta cheese was added with MSEs formulated with milk, as water phase, and sunflower oil (MSE-SO) or anhydrous milk fat (MSE-AMF), as lipid phase. A commercial whole milk Ricotta cheese (W-RC) was considered as reference. A probiotic Lacticaseibacillus rhamnosus strain was inoculated as free cells in W-RC or embedded into the MSEs and added to the low-fat Ricotta at the same reference fat content. After physico-chemical characterisation, L. rhamnosus viability and sample destructuring behaviour upon in vitro digestion were evaluated. At the end of in vitro digestion, both W-RC and sample containing MSE-SO were unable to protect cells. By contrast, sample with AMF ensured a sufficient probiotic viability, even after 14 days of storage at 4 °C. This result was attributed to system composition and structure. During the gastric phase, the presence of caseins and MG-AMF mixed structures induced the formation of clots, entrapping and protecting cells against the acidic pH of the stomach, as confirmed by confocal micrographs and particle size. During the intestinal phase, cell viability was guaranteed by the formation of mixed micelles promoted by MG. It was demonstrated that microbial cells located near MG structures where they found protection. 相似文献
64.
65.
《Ceramics International》2023,49(19):31559-31568
Oil-based drilling cutting pyrolysis residues (ODPRs) are one of the solid wastes from pyrolysis of the oil-based drilling cuttings (OBDCs) that need to be recycled as raw materials to avoid the possible pollution. In this study, a facile low-cost ceramic membrane for oil-in-water emulsions separation was prepared with ODPRs incorporating with fly ash as raw material. CaCO3 in ODPRs would decompose acting as pore-forming agent, and anorthite was formed in resultant membranes. The obtained membrane with 30 wt% ODPRs and 70 wt% fly ash fired at 1050 °C possessed apparent porosity of 38.2%, mean pore size of 0.4 μm, flexural strength of 13.1 MPa, and Darcy permeability of 1.06 × 10−13 m2. Consequently, commendable filtration performance for oil-in-water emulsions was presented. In addition, the ceramic membrane showed favorable recyclability and corrosion resistance. Leaching test indicated that the membrane is safe for oil-in-water emulsion separation. Hereby, this paper confirmed the availability of ODPRs for preparing ceramic filtration membranes, and provided a new environmental conservation way to treat oil-in-water emulsions that was consistent with the sustainable development goals. 相似文献
66.
Yangcenzi Xie Mingyang Chen Xinyu Liu Xiaoming Su Ming Li 《Advanced functional materials》2023,33(48):2307091
Epigenetic DNA methylations are early and frequently observed events in a diversity of diseases such as cancer. Despite the considerable clinical values for cancer liquid biopsy, quantitative analysis of DNA methylations remains a major challenge due to the lack of rapid, sensitive detection techniques. Here, an artificial intelligence-assisted label-free surface-enhanced Raman spectroscopy (SERS) (iMeSERS) biosensor is reported for simultaneous quantification of C5-methylcytosine (5mC) level and methylation ratio in DNA samples. This method utilizes the plasmonic Pickering emulsions as the biosensing platform for label-free SERS detection, formed upon the addition of a sub-microliter DNA sample to the hydrophobic Au nanostar-containing n-decane. Distinct spectral signatures of monophosphates of canonical deoxyribonucleotides (dNMPs) and the common methylation modification 5-methyl-2′-deoxycytidine (d5mCMP) are identified and distinguished by the iMeSERS biosensor. The deep learning algorithms trained with SERS signatures of dNMPs and d5mCMP are then applied to the quantitative analysis of global DNA methylation. The exceptional capability of the deep learning-driven approach is demonstrated for simultaneous quantification of the methylation ratio and level using a sub-microliter volume of DNA samples. This work shows the power of label-free SERS techniques combined with deep learning algorithms for quantitative analysis of epigenetic DNA modifications with great promises for clinical diagnosis. 相似文献
67.
为提高膳食中脂肪酸组成多样性,本研究以多重脂肪酸组成的复合油脂(玉米油、黄油、椰子油、藻油)为芯材,麦芽糊精、乳清蛋白浓缩物、酪蛋白酸钠为主要壁材,通过微射流耦合食品乳化剂制得O/W型均匀乳液,经喷雾干燥制得粉末微胶囊,利用单因素实验结合响应面分析包埋率影响因素,优化了最佳制备工艺: 进风温度170 ℃、均质压力31 MPa、乳化剂添加量0.3%,该产品的油脂包埋率高达85.75%。红外光谱(FTIR)分析证实油脂通过微胶囊得到了较好包埋,扫描电镜(SEM)图像显示产品表面虽略有凹陷但是结构致密完整。实验发现产品粉末的复原乳液液滴平均粒径为241.8 nm,zeta电位为-33.1 mV,显示该产品具有良好的复溶性与稳定性;激光共聚焦扫描显微镜(CLSM)发现油脂完整包埋且可均匀悬浮,显示微胶囊复原乳中油脂的保护效果好。 相似文献
68.
Bintao Hu Yongliang Zhao Zhangfan Ye Haitao Wang 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(16):2206215
Water-in-water (w/w) emulsions have been recognized for their broad applications in foods, cosmetics, and biomedical engineering. In this work, silica Janus nanosheets (JNs) with polyacrylic acid (PAA) chains grafted on one surface via crushing functional silica foams, and used silica JNs as Pickering stabilizer to produce stable water-in-water (w/w) emulsions from the aqueous two-phase system (ATPS) containing methacrylic acid (MAA) and NaCl are prepared. The interfacial area of w/w emulsions increases linearly with the concentration of silica JNs, and the interfacial coverage of nanosheets is calculated to be about 98%. After polymerizing w/w emulsions prepared from MAA/NaCl ATPS, it is found that silica JNs are entrapped at the interface of w/w emulsions with the smooth PAA-grafted surface located toward MAA-rich phase due to their specific interaction. These results show that functional silica JNs can be used as a promising amphiphilic Pickering stabilizer to produce well-defined w/w emulsions for numerous application fields. 相似文献
69.
通过实验研究表明,对低空间频率的振幅型银盐全息图形表面已形成浮雕,经漂白,浮雕深度成倍加深;浮雕深度随空间频率而变化,并且可用不同曝光量进行调制。选择适当条件,可降低零级光强,提高全息图的一级衍射效率。 相似文献
70.