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《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
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Shahzad Hussain Abdellatif A. Mohamed Mohamed S. Alamri Mohamed A. Ibraheem Akram A. Abdo Qasem Tawfiq Alsulami Ibrahim A. Ababtain 《Molecules (Basel, Switzerland)》2022,27(3)
This study was planned to explore the locally available natural sources of gum hydrocolloids as a natural modifier of different starch properties. Corn (CS), sweet potato (SPS), and Turkish bean (TBS) starches were mixed with locally extracted native or acetylated cactus (CG) and acacia (AG) gums at 2 and 5% replacement levels. The binary mixtures (starch–gums) were prepared in water, freeze dried, ground to powder, and stored airtight. A rapid viscoanalyzer (RVA), differential scanning calorimeter (DSC), texture analyzer, and dynamic rheometer were used to explore their pasting, thermal, textural, and rheological properties. The presence of acetylated AG or CG increased the final viscosity (FV) in all three starches when compared to starch pastes containing native gums. Plain SPS dispersion had a higher pasting temperature (PT) than CS and TBS. The addition of AG or CG increased the PT of CS, SPS, and TBS. The thermograms revealed the overall enthalpy change of the starch and gum blends: TBS > SPS > CS. The peak temperature (Tp) of starches increased with increasing gum concentration from 2 to 5% for both AG and CG native and modified gums. When compared to the control gels, the addition of 2% CG, either native or modified, reduced the syneresis of starch gels. However, further addition (5% CG) increased the gels’ syneresis. Furthermore, the syneresis for the first cycle on the fourth day was higher than the second cycle on the eighth day for all starches. The addition of native and acetylated CG reduced the hardness of starch gels at all concentrations tested. All of the starch dispersions had higher G′ than G″ values, indicating that they were more elastic and less viscous with or without the gums. The apparent viscosity of all starch gels decreased as shear was increased, with profiles indicating time-dependent thixotropic behavior. All of the starch gels, with or without gums, showed a non-Newtonian shear thinning trend in the shear stress vs. shear rate graphs. The addition of acetylated CG gum to CS resulted in a higher activation energy (Ea) than the native counterparts and the control. More specifically, starch gels with a higher gum concentration (5%) provided greater Ea than their native counterparts. 相似文献
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该研究利用超高效液相色谱-串联四极杆静电场轨道阱高分辨质谱(UHPLC/ESI-Q-Orbitrap)技术,对硒代蛋氨酸(SeMet)的色谱信息、分子离子质荷比和碎裂片段的质荷比进行采集,并对特征离子碎裂途径进行解析,建立了豆类中硒代蛋氨酸的检测方法。样品用三羟甲基氨基甲烷-盐酸(Tris-HCl)缓冲溶液溶解后,涡旋混匀,超声提取,在恒温水浴条件下酶解,离心后取上清液过0.22μm滤膜后上机检测。采用Hypersil GOLD HILIC(50 mm×2.1 mm,1.9μm)色谱柱进行分离,以0.2%(体积分数,下同)甲酸6 mmol/L甲酸铵水溶液和0.2%甲酸6 mmol/L甲酸铵乙腈溶液为流动相梯度洗脱,采用电喷雾正离子模式电离,在全扫描/数据依赖扫描模式(Full MS/dd-MS2)下进行检测,基质匹配标准校正法定量。结果表明,硒代蛋氨酸的基质效应为15.75%,在0.05~0.5 mg/L范围内线性关系良好,相关系数(r2)为0.9976,方法检出限(LOD)为0.015 mg/kg,定量下限(LOQ)为0.05 mg/kg;空白样品在0.1、0.2、0.4 mg/kg 3个加标水平下的平均回收率为77.6%~83.2%,日内相对标准偏差(RSDr)为2.8%~4.8%,日间相对标准偏差(RSDR)为4.1%~6.5%。将方法应用于实际样品的检测,得富硒黑豆、富硒红豆、富硒绿豆中硒代蛋氨酸的含量分别为0.252、0.163、0.184 mg/kg。该方法具有前处理操作简单、结果准确、重复性好等优点,适用于豆类中硒代蛋氨酸的检测。 相似文献
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I. O. B. Ewa 《光谱学快报》2013,46(5):885-900
Fast (14 MeV) neutrons have been successfully used in investigating the protein content of different food grains (Soya Beans, Sorghum, Maize and Beans) locally grown and consumed in Nigeria. Protein was estimated via nitrogen using the 14N(n, 2n)13N reaction. Quantification of nitrogen was achieved through a γ-γ coincidence counting of 511 keV positron emissions from the decaying 13N. The implication of the use of the emitted annihilation positrons, the interference introduced in the analytical energy spectra from other activated target nuclides present in the sample, as well as possible proton “knock on” reactions anticipated from cellulose in grain matrix were assessed, and their contributions to the 511 keV gamma energy resolved. For comparative purposes, replicates of samples analyzed through Fast Neutron Activation Analysis (FNAA) were investigated using the Kjeldahl method. The samples were carried through the Kjeldahl process of pre-digestion (with appropriate catalysts), digestion and titration. The results obtained through the Kjeldahl process were found to be in good agreement with those obtained using FNAA although slightly lower. Protein content (%) of Nigerian grains analyzed varied from a low 8.75 ± 2.96 for sorghum to 35.93 ± 0.31 for soya beans. 相似文献
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Yuchao Feng Xia Fan Shu Zhang Miao Yu Tong Wu Ying Liang Changyuan Wang Hongzhi Yang 《Molecules (Basel, Switzerland)》2022,27(12)
An ultra-high-performance liquid chromatography coupled with high-field quadrupole-orbitrap mass spectrometry (UHPLC-QE-MS) histological platform was used to analyze the effects of two thermal processing methods (cooking and steaming) on the nutritional metabolic components of black beans. Black beans had the most amino acids, followed by lipids and polyphenols, and more sugars. Multivariate statistical analysis indicated that heat processing significantly affected the metabolic component content in black beans, with effects varying among different components. Polyphenols, especially flavonoids and isoflavones, were highly susceptible. A total of 197 and 210 differential metabolites were identified in both raw black beans and cooked and steamed black beans, respectively. Cooking reduced the cumulative content of amino acids, lipids, polyphenols, sugars, and nucleosides, whereas steaming reduced amino acid and lipid content, slightly increased polyphenol content, and significantly increased sugar and nucleoside content. Our results indicated that metabolic components were better retained during steaming than cooking. Heat treatment had the greatest impact on amino acids, followed by polyphenols, fatty acids, sugars, and vitamins, indicating that cooking promotes the transformation of most substances and the synthesis of a few. The results of this study provide a basis for further research and development of nutritional products using black beans. 相似文献
7.
Marisol Vergara-Mendoza Genny R. Martínez Cristian Blanco-Tirado Marianny Y. Combariza 《Molecules (Basel, Switzerland)》2022,27(12)
The global chocolate value chain is based exclusively on cacao beans (CBs). With few exceptions, most CBs traded worldwide are produced under a linear economy model, where only 8 to 10% of the biomass ends up in chocolate-related products. This contribution reports the mass balance and composition dynamics of cacao fruit biomass outputs throughout one full year of the crop cycle. This information is relevant because future biorefinery developments and the efficient use of cacao fruits will depend on reliable, robust, and time-dependent compositional and mass balance data. Cacao husk (CH), beans (CBs), and placenta (CP) constitute, as dry weight, 8.92 ± 0.90 wt %, 8.87 ± 0.52 wt %, and 0.57 ± 0.05 wt % of the cacao fruit, respectively, while moisture makes up most of the biomass weight (71.6 ± 2.29 wt %). CH and CP are solid lignocellulosic outputs. Interestingly, the highest cellulose and lignin contents in CH coincide with cacao’s primary harvest season (October to January). CB contains carbohydrates, fats, protein, ash, and phenolic compounds. The total polyphenol content in CBs is time-dependent, reaching maxima values during the harvest seasons. In addition, the fruit contains 4.13 ± 0.80 wt % of CME, a sugar- and nutrient-rich liquid output, with an average of 20 wt % of simple sugars (glucose, fructose, and sucrose), in addition to minerals (mainly K and Ca) and proteins. The total carbohydrate content in CME changes dramatically throughout the year, with a minimum of 10 wt % from August to January and a maximum of 29 wt % in March. 相似文献
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Henry Delinc e Anna-Lucia C. H. Villavicencio Jorge Mancini-Filho 《Radiation Physics and Chemistry》1998,52(1-6):43-47
Beans are a major source of dietary protein in Brazil. However, high losses due to insect infestation occur after each harvest. To combat these losses, radiation processing of beans offers promise as an alternative to chemical treatment, provided the nutritional quality of beans is not impaired by the radiation treatment. Conflicting results have been published about the effect of radiation on the biological value of legume proteins. Therefore, two varieties of Brazilian beans were studied: 1) Phaseolus vulgaris L., var. carioca and 2) Vigna unguiculata (L.) Walp, var. macaçar. The beans were irradiated with doses of 0, 0.5, 1.0, 2.5, 5.0 and 10 kGy. Since irradiated beans will be consumed after appropriate storage, the beans under study were stored for 6 months at ambient temperature. Protein quality was measured by a biological assay employing the nitrogen balance approach in weanling rats. The animals were fed with optimally cooked beans, which were the only source of protein (10%). Nitrogen contents of legumes, diets, animal urine and faeces were determined by Kjeldahl analysis. The indices for apparent protein quality: net protein utilisation, digestibility and biological value were not influenced by irradiation. Thus, radiation treatment of Brazilian beans offers considerable promise as an effective insect disinfection process, without impairing the biological quality of the valuable bean protein. 相似文献
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Summary High-performance liquid chromatography with diode-array detection has been used for the separation and quantitation of phenolics
from fresh and processed green beans. Whole beans, pods and seeds of green beans were studied separately. Chromatographic
profiles from pods were more complex than those found in seeds. Flavonol glycosides were confined to quercetin and kaempferol
classes and they were typical of external parts of the fruit. Flavan-3-ols monomers ((+) catechin and (−) epicatechin) as
well as procyanidins structures were identified in pods and seeds. Chromatographic profiles from processed beans revealed
a polyphenolic composition similar to those found in pod fresh green beans. The chromatographic method was carefully validated
in regard to precision and accuracy. High reproducibility of peak area (RSD<3%) and calibration slopes (RSD<4%) was obtained.
Recoveries between 94–104% revealed good accuracy for the overall method. Application to quantitative determination in a representative
number of samples allowed good knowledge of the phenolic composition of green beans (Phaseolus vulgaris v.vulgaris). 相似文献