这项研究得到了国际教育研究所的学者救助基金的支持。

Aquafaba 与鹰嘴豆的分离
<ol><li>从当地杂货店获得鸡豌豆罐头, 并打开一个手动开罐器。</li>
	<li>标签罐从 A 到 J。</li>
	<li>用不锈钢网状厨房过滤器从 aquafaba 中分离出鹰嘴豆, 并权衡分离的鹰嘴豆和 aquafaba。</li>
</ol>获得具有代表性的鹰嘴豆和 Aquafaba 的样品进行化学分析。
<ol start="4"><li>在排出 aquafaba 后随机选择十鹰嘴豆, 以确定水分含量。</li>
	<li>将所选的鹰嘴豆放在干燥的锡中, 加热100至2摄氏度, 在烘干炉中放置16-18 小时。</li>
	<li>干燥后, 将鹰嘴豆磨成粉末, 进一步使用 (例如蛋白质和碳含量分析)。</li>
	<li>冻结 aquafaba 和 aquafaba 泡沫从每个来源到-20 摄氏度, 然后在冷冻干燥干燥。干 aquafaba 将用于氮和碳含量的测定。</li>
</ol>Aquafaba 功能属性
<ol start="8"><li>用2号壳杯测定25摄氏度的 aquafaba 黏度。<ol>
<li>把贝壳杯浸入 aquafaba。</li>
		<li>记录耗尽杯11所需的时间。当杯子从 aquafaba 上抬起时就开始计时器, 当水流离开杯子时停止。</li>
		<li>aquafaba 粘度可以通过提供与粘度和排水时间有关的杯形图来确定。</li>
	</ol>
</li>
	<li>发泡能力<ol>
<li>在不锈钢碗中混合 aquafaba 溶液 (100 毫升), 在速度设置为 10 2 分钟的手搅拌机。</li>
		<li>将 aquafaba 溶液的100毫升与 Vf100混合后立即记录泡沫体积, 方法是将泡沫放入一个已毕业的测量杯中。</li>
		<li>允许泡沫站立和干燥的时间, 以观察泡沫的稳定性, 并获得一个样品的干泡沫。</li>
	</ol>
</li>
</ol>鹰嘴豆种子的颜色参数
<ol start="10"><li>随机选择鹰嘴豆种子从每个罐头为颜色决心。</li>
	<li>在测量之前使用白色、黑色和参考标准校准猎人实验室色度计。</li>
	<li>颜色坐标值由 CIE 实验室系统12确定, 其中包括L (正值表示白色和0表示暗色)、(正数为红色和负值为绿色), b (正值为黄色, 负值为蓝色)。三人一天轻65°。</li>
</ol>蛋白质和碳含量
<ol start="13"><li>使用元素分析器13确定蛋白质和碳含量。蛋白质含量估计为氮含量乘以 6.2514。</li>
</ol>水分含量
<ol start="14"><li>在烘干烤箱15中, 通过将样品加热100至2摄氏度, 确定种子和 aquafaba 含水量。</li>
</ol>核磁共振光谱分析
<ol start="15"><li>样品准备<ol>
<li>在光谱之前, 离心机 aquafaba 样品在 9200 x g 10 分钟。离心后, 通过0.45 µm 注射器过滤器 (25 毫米注射器过滤器与聚四氟乙烯 (PTFE) 膜) 通过上清。将 aquafaba 样品 (0.4 毫升) 转移到核磁共振管中, wuth 50 毫克, 加入氘氧化物内, 并对样品进行核磁共振分析。</li>
		<li>对于先前所描述的干泡沫样品, 样品 (25 毫克) 是氘氧化物 (500 毫克), 而溶液则受核磁共振分析。</li>
		<li>将13C 核磁共振和1H 核磁共振的所有样本放置在5毫米的核磁共振管中。将氘氧化物和 3 (三甲基硅) 丙-22, 33 维4酸钠盐 (第三次会议) 添加到每个核磁共振管中, 以提供溶剂锁信号, 并分别作为内部标准。</li>
	</ol>
</li>
	<li>核磁共振条件<ol>
<li>用500兆赫核磁共振或类似的高场核磁共振光谱仪获得质子核磁共振谱), 每频谱至少有16次扫描, 使用的是双脉冲场梯度自旋回波质子核磁共振 (DPFGSE nmr) 脉冲序列16的水抑制程序。</li>
		<li>调整光谱变换, 将第三次会议峰值放在 0 ppm, 然后使用集成软件来确定存在的化合物的相对数量。</li>
	</ol>
</li>
</ol>电泳
注: 对于这一步骤, aquafaba, 产生了最稳定的泡沫 (品牌 H) 被选中。这个牌子不含盐。
<ol start="17"><li>样品准备<ol>
<li>介绍了 aquafaba 三离心再生纤维素超滤装置的上部储层, 各有3、10、50 kDa 的不同分子量切断 (MWCOs)。</li>
		<li>将离心过滤器单元放置在适当的离心机中, 4 °c, 离心机在 3900 x g 处为2小时, 获得上清和 retentate 馏分。在没有较高分子量 (兆瓦) 种的情况下, 将上清分数用于1H-核磁共振分析小分子。3 kDa 膜 retentate 分数用于电泳分离, 因为它被认为这膜将保留大多数蛋白质。</li>
		<li>采用改良的布拉德福德方法, 用牛血清白蛋白作为标准的17, 估计上清和 retenate 的蛋白质含量。</li>
		<li>将上清和 retentate 分数的样品放在离心管中, 并将这些分数置于适当的振动筛18的频率为 25 (10 分钟) 的震动。观察震动的溶液, 以确定泡沫是否由震动形成。</li>
		<li>将2.0 毫升蒸馏水添加到超滤装置中, retentate 二次离心处理, 以达到 diafilteration。将超滤装置以4°c 和 3900 x g 为 2 h 的第二离心机为准。</li>
		<li>将 retentate (0.025 克) 与1毫升0.02 米的三磷酸 ph 值7.4 或磷酸盐缓冲盐 (PBS) 的 ph 7.4 混合, 以溶解蛋白质。</li>
		<li>离心 21000 x g 的混合物1分钟。</li>
		<li>使用上清液, 用先前提到的修改后的布拉德福德来确定蛋白质含量。</li>
	</ol>
</li>
	<li>电泳分离 注: 3 kDa 截留分子量膜 retentate (上文所述) 采用月桂酸钠-聚丙烯酰胺凝胶电泳 (SDS) 进行电泳分离。<ol>
<li>用15% 聚丙烯酰胺溶液凝胶和5% 聚丙烯酰胺堆积凝胶制备聚丙烯酰胺凝胶。</li>
		<li>将20µg 蛋白样品应用于凝胶和 PageRuler Prestained 蛋白阶梯的一条车道上, 其范围为 10-170 kDa 到单独的聚丙烯酰胺凝胶车道。</li>
		<li>将凝胶与 Laemmli (1970)19中的小蛋白四细胞系统中的电流进行了调整。对于电泳操作条件, 凝胶染色和脱色遵循 Ratanapariyanuch et 。(2012)20。</li>
	</ol>
</li>
</ol>肽质指纹图谱
注: 从 SDS 页凝胶 3 kDa retentate (MWs 约 8, 10, 13, 14, 15, 20, 22, 31, 37, 55 和 100 kDa), 根据 Ratanapariyanuch et的胰蛋白酶消化剪切带。(2012)20并执行质谱分析。
<ol start="19"><li>凝胶消化<ol>
<li>在50% 乙腈 (ACN) 中浸泡100µL 200 毫米的碳酸氢铵 (NH4HCO3), 并在30°c 上孵育20分钟, 使带色变色两次。</li>
		<li>完成脱染后, 用 ACN (100 µL) 处理凝胶样品10分钟, 然后在真空下干燥, 使用离心真空蒸发器, 室温15分钟。</li>
		<li>将干燥的凝胶样品浸泡在100毫米 NH4HCO3溶液中100µL 10 毫米 dithiothreitol (德勤) 中, 并在56摄氏度孵化1小时。</li>
		<li>去除多余的减少缓冲, 并用100µL 烷基化缓冲器 (质谱 (MS) 级水中的100毫米 iodoacetamide) 替换。</li>
		<li>在室温下将凝胶样品在黑暗中孵化30分钟。</li>
		<li>两次洗涤凝胶样品200毫米 NH4HCO3 (100 µL), 将凝胶浸泡在 ACN (100 µL) 中, 用200毫米 NH4HCO3 (100 µL) 重新膨胀凝胶, 再用 ACN (100 µL) 治疗, 再收缩。</li>
		<li>将离心真空蒸发器中的 ACN 和干燥的凝胶样品排出15分钟。</li>
		<li>使用20µL 胰蛋白酶缓冲器 (50 ng/µL 胰蛋白酶 1:1, 200 毫米 nh4HCO3: 胰蛋白酶库存解决方案) 重新膨胀干胶样品, 随后增加30µL 200 毫米 NH4HCO3到每个样品。</li>
		<li>在30摄氏度的 Thermomixer 上孵化样品, 在300转每分钟晃动。</li>
		<li>通过在 0.1% ACN 中加入1/10 的最终体积 (混合物的体积) 和胰蛋白酶的 1% trifluoracetic 酸, 从凝胶样品中提取8肽, 并利用离心法在真空下干燥, 以防止胰蛋白酶消化反应。真空蒸发器。</li>
		<li>在质谱分析前-80 °c 储存胰蛋白酶肽。</li>
	</ol>
</li>
	<li>质谱<ol>
<li>通过添加12µL 的 MS 级水来重建胰蛋白酶肽: ACN: 甲酸 (97:3: 0.1, v/v), 然后涡旋1至2分钟以溶解肽。</li>
		<li>离心机的结果解决方案在1.8万克10分钟4摄氏度。</li>
		<li>转移解决方案整除数 (10 µL) 到 MS 瓶的液相色谱-串联质谱 (LC-ms/毫秒) 分析的四极飞行时间 (QTOF) 质谱仪配备了液相色谱仪器和 LC MS 接口。</li>
		<li>用高容量高效液相色谱芯片进行色谱肽分离: 由 360 nL 富集柱和75µm x 150 毫米分析柱组成, 既装满 C18-A、180Å、3µm 固定相。</li>
		<li>将样品装载到富集柱上, 在水中0.1% 甲酸, 流速为2.0 µL/分钟。</li>
		<li>将样品从浓缩柱转移到分析柱上。</li>
		<li>肽分离条件为: 由溶剂 a (水中0.1% 甲酸) 和溶剂 B (ACN 中0.1% 甲酸) 组成的线性梯度溶剂体系。线性梯度开始与3% 溶剂 b 增加到25% 溶剂 b 50 分钟。随后, 溶剂 B 在流速为0.3 µL/分钟时, 从25增加到 90% 10 分钟。</li>
		<li>获得正离子电喷雾质谱数据, 使用毛细管电压设置在 1900 v, 片段离子设置在 360 v, 干燥气体 (氮气) 设置在225°c, 流速为12.0 升/分。</li>
		<li>收集光谱结果的质量范围为 250-1700 (质量/电荷;m/z)扫描率为8谱/秒. 收集 ms/毫秒数据, 其范围为50-1700 个m/z , 设置隔离宽度为1.3 个原子质量单位。选择前20最强的前体离子为每 ms 扫描的串联 ms 与0.25 分钟的积极排斥。</li>
	</ol>
</li>
	<li>蛋白质鉴定<ol>
<li>使用安捷伦 MassHunter 定性分析软件将光谱数据转换为质量/电荷数据格式。</li>
		<li>根据 UniProt Cicer arietinum (鹰嘴豆) 数据库处理数据, 使用 SpectrumMill 作为数据库搜索引擎。</li>
		<li>包括搜索参数, 如片段质量误差 50 ppm, 父母质量误差为 20 ppm, 胰蛋白酶裂解特异性, 和 carbamidomethyl 作为固定修饰半胱氨酸。</li>
	</ol>
</li>
</ol>

<ol>
	<li>Janssen, M., Busch, C., R&#246;diger, M., Hamm, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Motives+of+consumers+following+a+vegan+diet+and+their+attitudes+towards+animal+agriculture.">Motives of consumers following a vegan diet and their attitudes towards animal agriculture.</a> Appetite. 105, 643-651 (2016).</li><li>. Egg Replacement Ingredient Market: Global Industry Analysis and Opportunity Assessment, 2016-2026 Available from: <a target="_blank" href="https://www.prnewswire.com/news-releases/egg-replacement-ingredient-market-global-industry-analysis-and-opportunity-assessment-2016-2026-300370861.html">https://www.prnewswire.com/news-releases/egg-replacement-ingredient-market-global-industry-analysis-and-opportunity-assessment-2016-2026-300370861.html</a> (2016)</li><li>Joshi, P. K., Parthasarathy Rao, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Global+and+regional+pulse+economies+current+trends+and+outlook.">Global and regional pulse economies current trends and outlook.</a> IFPRI Discussion Paper 01544. , 149 (2016).</li><li>Oomah, B. D., Patras, A., Rawson, A., Singh, N., Compos-Vega, R., Tiwari, B. K., Gowen, A., Mckenna, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chemistry+of+pulses.">Chemistry of pulses.</a> Pulse Foods. , 9-55 (2011).</li><li>Gugger, E. T., Galuska, P., Tremaine, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Legume-based+dairy+substitute+and+consumable+food+products+incorporating+same.">Legume-based dairy substitute and consumable food products incorporating same.</a> United States Patent Application. , (2016).</li><li>Tetrick, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plant-based+egg+substitute+and+method+of+manufacture.">Plant-based egg substitute and method of manufacture.</a> World Patent. , (2013).</li><li>Singh, G. D., Wani, A. A., Kaur, D., Sogi, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterisation+and+functional+properties+of+proteins+of+some+Indian+chickpea+(Cicer+arietinum)+cultivars.">Characterisation and functional properties of proteins of some Indian chickpea (Cicer arietinum) cultivars.</a> J. Sci. Food Agric. 88 (5), 778-786 (2008).</li><li>Nleya, T. M., Arganosa, G. C., Vandenberg, A., Tyler, R. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genotype+and+environment+effect+on+canning+quality+of+kabuli+chickpea.">Genotype and environment effect on canning quality of kabuli chickpea.</a> Can. J. Plant Sci. 82 (2), 267-272 (2002).</li><li>Vaz Patto, M. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Achievements+and+Challenges+in+Improving+the+Nutritional+Quality+of+Food+Legumes.">Achievements and Challenges in Improving the Nutritional Quality of Food Legumes.</a> Crit. Rev. Plant Sci. 34, 105-143 (2015).</li><li>Ratanapariyanuch, K., Clancy, J., Emami, S., Cutler, J., Reaney, M. J. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physical,+chemical,+and+lubricant+properties+of+Brassicaceae+oil.">Physical, chemical, and lubricant properties of Brassicaceae oil.</a> Eur. J. Lipid Sci. Technol. 115, 1005-1012 (2013).</li><li>Hunter, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photoelectric+color-difference+meter.">Photoelectric color-difference meter.</a> J. Opt. Soc. Am. 48, 985-995 (1958).</li><li>Sweeney, R. A., Rexroad, P. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+LECO+FP-228+'N+Determinator'+with+AOAC+copper+catalyst+Kjeldahl+method+for+crude+protein.">Comparison of LECO FP-228 'N Determinator' with AOAC copper catalyst Kjeldahl method for crude protein.</a> JAOAC. 70, 1028-1032 (1987).</li><li>Boye, J. I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+the+functional+properties+of+pea,+chickpea+and+lentil+protein+concentrates+processed+using+ultrafiltration+and+isoelectric+precipitation+techniques.">Comparison of the functional properties of pea, chickpea and lentil protein concentrates processed using ultrafiltration and isoelectric precipitation techniques.</a> Food Res Int. 43, 537-546 (2010).</li><li>Ratanapariyanuch, K., Shim, Y. Y., Emami, S., Reaney, M. J. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protein+concentrate+production+from+thin+stillage.">Protein concentrate production from thin stillage.</a> J. Agric. Food Chem. 64, 9488-9496 (2016).</li><li>Ratanapariyanuch, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+NMR+method+for+the+quantification+of+organic+compounds+in+thin+stillage.">Rapid NMR method for the quantification of organic compounds in thin stillage.</a> J. Agric. Food Chem. 59, 10454-10460 (2011).</li><li>Bradford, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+rapid+and+sensitive+method+for+the+quantitation+of+microgram+quantities+of+protein+utilizing+the+principle+of+protein-dye+binding.">A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding.</a> Anal. Biochem. 72, 248-254 (1976).</li><li>Burnett, P. G. G., Olivia, C. M., Okinyo-Owiti, D. P., Reaney, M. J. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Orbitide+composition+of+the+flax+core+collection+(FCC).">Orbitide composition of the flax core collection (FCC).</a> J. Agric. Food Chem. 64, 5197-5206 (2016).</li><li>Laemmli, U. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cleavage+of+structural+proteins+during+the+assembly+of+the+head+of+bacteriophage+T4.">Cleavage of structural proteins during the assembly of the head of bacteriophage T4.</a> Nature. 227, 680-685 (1970).</li><li>Ratanapariyanuch, K., Tyler, R. T., Shim, Y. Y., Reaney, M. J. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biorefinery+process+for+protein+extraction+from+oriental+mustard+(Brassica+juncea+L.,+Czern.)+meal+using+ethanol+stillage.">Biorefinery process for protein extraction from oriental mustard (Brassica juncea L., Czern.) meal using ethanol stillage.</a> AMB Express. 2, 1-9 (2012).</li><li>Lv, Q., Yang, Y., Zhao, Y., Gu, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+study+on+separation+and+purification+of+isoflavones+from+the+seeds+and+sprouts+of+chickpea+by+HSCCC.">Comparative study on separation and purification of isoflavones from the seeds and sprouts of chickpea by HSCCC.</a> J. Liq Chromatogr Relat. Technol. 32, 2879-2892 (2009).</li><li>Behera, M. R., Varade, S. R., Ghosh, P., Paul, P., Negi, A. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Foaming+in+micellar+solutions:+effects+of+surfactant,+salt,+and+oil+concentrations.">Foaming in micellar solutions: effects of surfactant, salt, and oil concentrations.</a> Ind. Eng. Chem. Res. 53, 18497-18507 (2014).</li><li>Tan, S. H., Mailer, R. J., Blanchard, C. L., Agboola, S. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Canola+proteins+for+human+consumption:+Extraction,+profile,+and+functional+properties.">Canola proteins for human consumption: Extraction, profile, and functional properties.</a> J. Food Sci. 76, R16-R28 (2011).</li><li>Thiede, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peptide+mass+fingerprinting.">Peptide mass fingerprinting.</a> Methods. 35, 237-247 (2005).</li><li>Hwang, H. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Application+of+NMR+spectroscopy+for+foods+and+lipids.">Application of NMR spectroscopy for foods and lipids.</a> Advances in NMR spectroscopy for lipid oxidation assessment. , 11-13 (2017).</li></ol>

作者没有什么可透露的。

在这项研究中, 我们发现, 来自不同商业来源的鹰嘴豆 aquafaba 产生的泡沫, 两者的性质 (体积和稳定性的泡沫) 和化学成分。aquafaba 粘度与含水率呈正相关。泡沫体积增大 (Vf100) 与这些参数无关。添加剂, 如盐和 EDTA 二钠可以抑制粘度和泡沫稳定性, 因为 aquafaba 从鹰嘴豆罐头与这些添加剂有较低的粘度和产生泡沫的低泡沫稳定性。此结果与 Behera et al不同。(2014)22在报告中, 在有盐的情况下, 胶束泡沫体积减少, 泡沫破裂率因盐而减慢。鹰嘴豆 aquafaba 从加盐煮熟的样品中得到的水分和含盐量比 aquafaba 鹰嘴豆的低碳含量还高。在烹调鹰嘴豆之前加入盐可能有有限的淀粉和蛋白质肿胀23。
蛋白质分离的膜过滤后, SDS 页和肽的质量指纹图谱表明, aquafaba 蛋白是众所周知的热溶性亲水物种。奇怪的是, 也有证据表明, 胰蛋白酶的碎片, 表明这一材料被污染的 ascochyta 疫病。核磁共振分析发现多达20小有机溶质, 包括醇, 醋酸, 乳酸和琥珀酸。结果表明, 发酵产物在 aquafaba 中积累。这些化合物可能是微生物在浸泡种子之前产生的。泡沫和果汁的质子核磁共振谱表明, 果汁中存在异黄酮和挥发性成分, 而泡沫主要含有多糖、蔗糖和蛋白质。也感兴趣的1H 核磁共振表明存在核酸 (可能脱氧核糖核酸)。
明确的过程中使用的罐头影响 aquafaba 的性能和质量。消费者有可能根据溶液浓度来识别更好的 aquafaba 来源。主要来源可以被选择罐头, 不用增加盐或 EDTA。在罐头被打开之后, 消费者可以测量鹰嘴豆和 aquafaba 质量的比值来确定浓度。但是, 制造商可以标准化加工条件, 并生产标准化的 aquafaba 作为商业产品。
本研究采用肽质指纹图谱和1h-核磁共振分析 aquafaba 的组成。肽质指纹识别 aquafaba 蛋白对发泡性能的贡献。已知的蛋白质的热稳定性是众所周知的。这项技术有足够的洞察力来识别与种子真菌生物体相关的蛋白质的存在。但是, 各种因素可能会影响结果24。关键步骤是样品制备, 蛋白质纯化, 分离之前的凝胶电泳, 胰蛋白酶消化和大规模搜索, 导致鉴定。胰蛋白酶片段的软件数据库搜索考虑到许多肽的修改, 包括 carbamylated 赖氨酸, 氧化蛋氨酸, 焦谷氨酸酸, deamidated 天门冬, 磷酸化丝氨酸, 苏氨酸, 和酪氨酸为变量修改.然后用半胰蛋白酶非特异 C 终点和半胰蛋白酶非特异 N 终点搜索两阶段分析的验证命中。在迭代分析之后, 为肽和蛋白质提供了1% 错误发现率的验证。
质子核磁共振用于测定 aquafaba 中有机小分子的存在。它们的光谱识别出了几种化合物。对 aquafaba 样品进行过滤和离心处理, 以消除不溶性微粒, 干扰核磁共振峰值形状, 降低灵敏度。此外, 采用溶剂抑制方法提高了与强水共振引起的广义基线重叠的分子的核磁共振探测器灵敏度。
质子核磁共振是食品质量控制中的一个既定工具。与 GC/ms、lc/UV 和 lc/ms 等色谱方法相比, 1h-核磁共振方法通常不太敏感。但是, 这种方法只需要很少的样本准备, 就能在一个测量25中实现快速结果和广泛的信息。如果存在足够的材料, 则1H 核磁共振也是一种非常可靠的方法, 用于定量分析和澄清未知化合物的化学结构。

越来越多的素食产品正在开发, 模仿肉类, 牛奶和鸡蛋的性质。脉冲的功能特性对其在食品中的应用具有重要的意义, 在动物蛋白替代品的开发中正在探索它们的性质。例如, 乳品替代品销售额在2015年为88亿美元, 这个市场正在迅速增长。预计到 2024年, 这个市场将增长到350.6亿美元。此外, 以植物为基础的牛奶替代品需求上升的趋势, 部分原因是消费者对牛奶生产中经常使用的胆固醇、抗生素和生长激素的关注, 这是1。同样, 蔬菜蛋白和胶体蛋乳粉市场也在迅速扩大, 预计在未来8年内, 这些材料的年增长率将达到 5.8%, 预计在 2026年2将销售15亿美元。越来越多的消费者喜欢素食蛋白来源, 过敏原减少了饮食, 减少了食品的碳足迹。由于高蛋白质含量、膳食纤维和脉冲的低饱和脂肪含量3, 对脉冲基产品的需求, 特别是从扁豆、鹰嘴豆和蚕豆的需求量正在稳步增长。脉冲还含有具有潜在有益的生物活性的植物化学物质4。
商业实体、科学家和个人已经采取不同的方法来交流鹰嘴豆的鸡蛋和牛奶替代品的质量特性。Gugger et al。5从高淀粉谷物 (包括小豆和鹰嘴豆) 生产出一种类似牛奶的产品。在他们描述的方法中, 拥护者试图表明他们的产品是独一无二的, 不同于 "aquafaba"6。在另一种商业方法 Tetrick et . 阐明。7开发了一种基于植物的卵子替代品。他们的专利申请描述了将脉冲面粉与已知的增稠剂相结合的方法, 模拟了烘烤材料中蛋清的作用。典型配方包括80-90% 脉粉和10-20% 增稠剂。
同行评审的文献也表明了鹰嘴豆的功能, 并表明从 kabuli 和鹰嘴豆面粉中获得的白蛋白组分具有良好的乳化性能。他们还发现鹰嘴豆源对白蛋白产量和性能的显著影响8。
在最初的互联网报告描述了法国厨师若埃尔·瓦西·阿德奇门林格尔的 "aquafaba" 之后, 一个开源运动显示了 aquafaba 在许多食品应用中取代蛋清和乳制品蛋白的效用。有许多高度被观看的网页和 YouTube 视频显示, aquafaba 在食品中的加入, 模仿冰淇淋, 蛋白酥皮, 奶酪, 蛋黄酱, 炒鸡蛋, 和生奶油的品质。大多数开拓者提供开源 aquafaba 应用 (食谱) 获得他们的材料, 通过紧张的罐装鹰嘴豆和使用的液体在他们的食谱。这些人大多不是训练有素的科学家。视频评论部分表明, 被调查者复制了食谱, 有些人未能复制 aquafaba 倡导者的成功。
所有三种方法 (公司、科学和开源) 开发鸡蛋和牛奶替代品都有优点, 但缺少一个重要的方面。应用科学家, 基础科学家和个人发布脉冲产品已经不完全的特征和标准化他们的输入材料。对某一特定用途的产品进行标准化是一项正常的工业实践。鹰嘴豆品种没有标准化的 aquafaba 质量和工业罐头做法标准化, 以生产一致的鹰嘴豆不 aquafaba。
在对其他商品进行研究的基础上, 基因型和环境对脉冲 aquafaba 质量的影响是可以预测的。众所周知, 基因型和环境都影响 kabuli 鹰嘴豆罐头性能9。典型地, 基因型效应在相关物种之间很大, 在物种的成员中较小。通过身份保护可以最大限度地减少物理和化学性质的变化, 允许选择具有所需属性的品种。环境影响也可以很大, 并通过质量评估和混合到特定测试中的标准性能来管理10。
鹰嘴豆在商业生产中有许多不同的基因品种。举例来说, 萨斯喀彻温省大学作物发展中心是商业鹰嘴豆种质资源的主要来源, 自1980年以来已发布了23鹰嘴豆品种, 其中6是目前推荐在加拿大种植的。虽然科学手稿经常描述研究中所使用的品种, 但所调查的专利和互联网页面并没有表明所使用的品种或鹰嘴豆的来源。标准化的品种和处理可以帮助用户提高其使用鹰嘴豆的成功, 但这些信息是不可用的罐装鹰嘴豆产品。
本研究的目的是确定贡献起泡性的 aquafaba 成分。本文对商业鹰嘴豆品牌 aquafaba 的流变特性进行了比较, 用核磁共振、电泳、肽质指纹图谱对其化学性质进行了研究。根据我们的知识, 这是第一个描述 aquafaba 增粘剂成分的化学成分和功能特性的研究。

<table border="0" cellpadding="0" cellspacing="0" width="803">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Freeze Dryer</td>
			<td style="width:217px;"></td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Stoppering Tray Dryer</td>
			<td style="width:217px;">Labconco Inc.</td>
			<td style="width:100px;">7948040</td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Mixer&#160;</td>
			<td style="width:217px;"></td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Stainless steel hand mixer&#160;</td>
			<td style="width:217px;">Loblaws</td>
			<td style="width:100px;">PC2200MR</td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Viscosity Measurement&#160;</td>
			<td style="width:217px;"></td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:219px;">Shell cup No. 2&#160;</td>
			<td style="width:217px;">Norcross Corp.</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Color Measurement&#160;</td>
			<td style="width:217px;"></td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Colorflex HunterLab spectrophotometer&#160;</td>
			<td style="width:217px;">Hunter Associates Laboratory Inc.</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Protein and Carbon Contents&#160;</td>
			<td style="width:217px;"></td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Elemental analyzer&#160;&#160;</td>
			<td style="width:217px;">LECO Corp.</td>
			<td style="width:100px;">CN628</td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">NMR Spectrometry</td>
			<td style="width:217px;"></td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Spectrafuge 24D&#160;&#160;</td>
			<td style="width:217px;">Labnet International Inc.</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Syringe filters&#160;</td>
			<td style="width:217px;">VWR International</td>
			<td style="width:100px;">CA28145-497</td>
			<td style="width:267px;">25 mm, with 0.45 &#181;m PTFE membrane</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Deuterium oxide&#160;</td>
			<td style="width:217px;">Cambridge Isotope Laboratories Inc.</td>
			<td style="width:100px;">7789-20-0</td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">3-(trimethylsilyl)propionic-2,2,3,3-d4 acid sodium salt</td>
			<td style="width:217px;">Sigma-Aldrich</td>
			<td style="width:100px;">169913-1G</td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Bruker Avance 500 MHz NMR spectrometer&#160;</td>
			<td style="width:217px;">Bruker BioSpin</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">TopSpin 3.2 software&#160;</td>
			<td style="width:217px;">Bruker BioSpin GmbH</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Electrophoresis&#160;</td>
			<td style="width:217px;"></td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Regenerated cellulose membrane&#160;</td>
			<td style="width:217px;">Millipore Corp.</td>
			<td style="width:100px;"></td>
			<td style="width:267px;">3, 10, 50 kDa (MWCO)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Centrifugal filter unit&#160;</td>
			<td style="width:217px;">Millipore Corp.</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Benchtop centrifuge&#160;</td>
			<td style="width:217px;">Allegra X-22R, Beckman Coulter Canada Inc.</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Mixer Mill MM 300&#160; bead mill&#160;</td>
			<td style="width:217px;">F. Kurt Retsch GmbH &#38; Co. KG</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Eppendorf centrifuge 5417C</td>
			<td style="width:217px;">Eppendorf</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Phosphate buffered saline, pH 7.4</td>
			<td style="width:217px;">Sigma-Aldrich</td>
			<td style="width:100px;">P3813-10PAK</td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Tris-HCl buffer pH 7.4&#160;</td>
			<td style="width:217px;">Sigma-Aldrich</td>
			<td style="width:100px;">T6789-10PAK</td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="29">
			<td height="29" style="height:29px;width:219px;">PageRuler Prestained Protein Ladder&#160;</td>
			<td style="width:217px;">Fisher Scientific</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Mini-Protein Tetra Cell system</td>
			<td style="width:217px;">BioRad</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Peptide Mass Fingerprinting</td>
			<td style="width:217px;"></td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Thermo-Savant SpeedVac</td>
			<td style="width:217px;">BioSurplus</td>
			<td style="width:100px;"></td>
			<td style="width:267px;">Centrifugal vacuum evaporator&#160;</td>
		</tr>
		<tr height="46">
			<td height="46" style="height:46px;width:219px;">Trypsin buffer&#160;</td>
			<td style="width:217px;"></td>
			<td style="width:100px;"></td>
			<td style="width:267px;">20 &#181;L trypsin in 1 mM hydrochloric acid and 200 mM NH4HCO3</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Iodoacetamide</td>
			<td style="width:217px;">Sigma-Aldrich</td>
			<td style="width:100px;">I1149-5 g</td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Trifluoroacetic acid&#160;</td>
			<td style="width:217px;">Fluka</td>
			<td style="width:100px;">BB360P050</td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Acetonitrile</td>
			<td style="width:217px;">Fisher Scientific&#160;</td>
			<td style="width:100px;">L14734</td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">Formic acid&#160;</td>
			<td style="width:217px;">Sigma-Aldrich</td>
			<td style="width:100px;">33015-500mL</td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Mass spectrometry vial&#160;</td>
			<td style="width:217px;">Agilent Technologies Canada Ltd.</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:219px;">Agilent 6550 iFunnel quadrupole time-of-flight mass spectrometer&#160;</td>
			<td style="width:217px;">Agilent Technologies Canada Ltd.</td>
			<td style="width:100px;"></td>
			<td style="width:267px;">Agilent 1260 series LC instrument and Agilent Chip Cube LC-MS interface</td>
		</tr>
		<tr height="64">
			<td height="64" style="height:64px;width:219px;">HPLC-Chip II: G4240-62030 Polaris-HR-Chip_3C18&#160;</td>
			<td style="width:217px;"></td>
			<td style="width:100px;"></td>
			<td style="width:267px;">360 nL enrichment column and 75 &#181;m &#215; 150 mm analytical column, both packed with Polaris C18-A, 180&#197;, 3 &#181;m stationary phase.&#160;</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Agilent MassHunter Qualitative Analysis Software</td>
			<td style="width:217px;">Agilent Technologies Canada Ltd.</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">SpectrumMill data extractors</td>
			<td style="width:217px;">Agilent Technologies Canada Ltd.</td>
			<td style="width:100px;"></td>
			<td style="width:267px;"></td>
		</tr>
	</tbody>
</table>

composition and properties of aquafaba: water recovered from commercially canned chickpeas

鹰嘴豆和其他脉冲通常被出售为罐装产品包装在一个厚的溶液或盐水。这一解决方案最近被证明可以产生稳定的泡沫和乳液, 并可作为一个增稠剂。最近, 通过互联网提高了对该产品的兴趣, 建议该解决方案 (现在被越来越多的社区称为 aquafaba) 可以用来替代鸡蛋和牛奶蛋白。由于 aquafaba 是新的和正在开发的基于互联网的社区很少知道它的组成或性质。Aquafaba 从10个商用罐头鹰嘴豆产品中回收, 研究了 Aquafaba 成分、密度、粘度和发泡性能之间的相关性。质子核磁共振用于表征超滤前后的 aquafaba 成分, 通过不同分子量切割的膜 (MWCOs 3、10或 50 kDa)。文中还介绍了一种电泳和多肽质量指纹图谱。这些方法提供了有关负责 aquafaba 功能属性的组件的宝贵信息。这些信息将允许开发的做法, 以生产标准的商业 aquafaba 产品, 并可能帮助消费者选择的产品的优越或一致的效用。

Watch this Scientific Journal Video about Composition and Properties of Aquafaba: Water Recovered from Commercially Canned Chickpeas at JoVE.com

Composition and Properties of Aquafaba: Water Recovered from Commercially Canned Chickpeas

Aquafaba 是从罐装鹰嘴豆的粘性果汁, 当搅拌旺盛, 产生一个相对稳定的白色泡沫或泡沫。主要的研究目标是通过核磁共振 (NMR)、超滤、电泳和多肽质量指纹 aquafaba 来识别贡献 viscosifying/增稠性的成分。

Aquafaba 的成分和性质: 从商用罐装鹰嘴中回收的水

Chickpea and other pulses are commonly sold as canned products packed in a thick solution or a brine. This solution has recently been shown to produce ...

composition-properties-aquafaba-water-recovered-from-commercially

Nanyang Technological University

Research

JoVE Journal

Environment

33.2K 次观看.  University of Saskatchewan. Aquafaba 是从罐装鹰嘴豆的粘性果汁, 当搅拌旺盛, 产生一个相对稳定的白色泡沫或泡沫。主要的研究目标是通过核磁共振 (NMR)、超滤、电泳和多肽质量指纹 aquafaba 来识别贡献 viscosifying/增稠性的成分。

视频: Composition and Properties of Aquafaba: Water Recovered from Commercially Canned Chickpeas

Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading

Eutrophication is a water quality issue in lakes worldwide, and there is a critical need to identify and control nutrient sources. Internal phosphorus (P) loading from lake sediments can account for a substantial portion of the total P load in eutrophic, and some mesotrophic, lakes. Laboratory determination of P release rates from sediment cores is one approach for determining the role of internal P loading and guiding management decisions. Two principal alternatives to experimental determination of sediment P release exist for estimating internal load: in situ measurements of changes in hypolimnetic P over time and P mass balance. The experimental approach using laboratory-based sediment incubations to quantify internal P load is a direct method, making it a valuable tool for lake management and restoration.
Laboratory incubations of sediment cores can help determine the relative importance of internal vs. external P loads, as well as be used to answer a variety of lake management and research questions. We illustrate the use of sediment core incubations to assess the effectiveness of an aluminum sulfate (alum) treatment for reducing sediment P release. Other research questions that can be investigated using this approach include the effects of sediment resuspension and bioturbation on P release.
The approach also has limitations. Assumptions must be made with respect to: extrapolating results from sediment cores to the entire lake; deciding over what time periods to measure nutrient release; and addressing possible core tube artifacts. A comprehensive dissolved oxygen monitoring strategy to assess temporal and spatial redox status in the lake provides greater confidence in annual P loads estimated from sediment core incubations.

Lake eutrophication is a water quality issue worldwide, making the need to identify and control nutrient sources critical. Laboratory determination of phosphorus release rates from sediment cores is a valuable approach for determining the role of internal phosphorus loading and guiding management decisions.

实验室确定的磷通量湖泊沉积物作为内部磷载入一个测量

Eutrophication is a water quality issue in lakes worldwide, and there is a critical need to identify and control nutrient sources. Internal phosphorus (P) ...

科研

环境科学

EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. I. Collection of Virus Samples

EPA Method 1615 was developed with a goal of providing a standard method for measuring enteroviruses and noroviruses in environmental and drinking waters. The standardized sampling component of the method concentrates viruses that may be present in water by passage of a minimum specified volume of water through an electropositive cartridge filter. The minimum specified volumes for surface and finished/ground water are 300 L and 1,500 L, respectively. A major method limitation is the tendency for the filters to clog before meeting the sample volume requirement. Studies using two different, but equivalent, cartridge filter options showed that filter clogging was a problem with 10% of the samples with one of the filter types compared to 6% with the other filter type. Clogging tends to increase with turbidity, but cannot be predicted based on turbidity measurements only. From a cost standpoint one of the filter options is preferable over the other, but the water quality and experience with the water system to be sampled should be taken into consideration in making filter selections.

EPA Method 1615 uses an electropositive filter to concentrate enteroviruses and noroviruses in environmental and drinking waters. This manuscript describes the procedure for collecting samples for Method 1615 analyses.

EPA方法1615测量肠道病毒和诺瓦克病毒发生水由文化和RT-qPCR的了。病毒样本的收集I.

EPA Method 1615 was developed with a goal of providing a standard method for measuring enteroviruses and noroviruses in environmental and drinking waters. ...

EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. Part III. Virus Detection by RT-qPCR

EPA Method 1615 measures enteroviruses and noroviruses present in environmental and drinking waters. This method was developed with the goal of having a standardized method for use in multiple analytical laboratories during monitoring period 3 of the Unregulated Contaminant Monitoring Rule. Herein we present the protocol for extraction of viral ribonucleic acid (RNA) from water sample concentrates and for quantitatively measuring enterovirus and norovirus concentrations using reverse transcription-quantitative PCR (RT-qPCR). Virus concentrations for the molecular assay are calculated in terms of genomic copies of viral RNA per liter based upon a standard curve. The method uses a number of quality controls to increase data quality and to reduce interlaboratory and intralaboratory variation. The method has been evaluated by examining virus recovery from ground and reagent grade waters seeded with poliovirus type 3 and murine norovirus as a surrogate for human noroviruses. Mean poliovirus recoveries were 20% in groundwaters and 44% in reagent grade water. Mean murine norovirus recoveries with the RT-qPCR assay were 30% in groundwaters and 4% in reagent grade water.

Here we present a procedure to quantify enterovirus and norovirus in environmental and drinking waters using reverse transcription-quantitative PCR. Mean virus recovery from groundwater with this standardized procedure from EPA Method 1615 was 20% for poliovirus and 30% for murine norovirus.

EPA方法1615测量肠道病毒和诺瓦克病毒发生水由文化和RT-qPCR的了。第三部分。病毒检测用RT-qPCR的

EPA Method 1615 measures enteroviruses and noroviruses present in environmental and drinking waters. This method was developed with the goal of having a ...

Protocol for Measuring the Thermal Properties of a Supercooled Synthetic Sand-water-gas-methane Hydrate Sample

Methane hydrates (MHs) are present in large amounts in the ocean floor and permafrost regions. Methane and hydrogen hydrates are being studied as future energy resources and energy storage media. To develop a method for gas production from natural MH-bearing sediments and hydrate-based technologies, it is imperative to understand the thermal properties of gas hydrates.
The thermal properties' measurements of samples comprising sand, water, methane, and MH are difficult because the melting heat of MH may affect the measurements. To solve this problem, we performed thermal properties' measurements at supercooled conditions during MH formation. The measurement protocol, calculation method of the saturation change, and tips for thermal constants' analysis of the sample using transient plane source techniques are described here.
The effect of the formation heat of MH on measurement is very small because the gas hydrate formation rate is very slow. This measurement method can be applied to the thermal properties of the gas hydrate-water-guest gas system, which contains hydrogen, CO2, and ozone hydrates, because the characteristic low formation rate of gas hydrate is not unique to MH. The key point of this method is the low rate of phase transition of the target material. Hence, this method may be applied to other materials having low phase-transition rates.

We present a protocol for measuring the thermal properties of synthetic hydrate-bearing sediment samples comprising sand, water, methane, and methane hydrate.

协议测量过冷的合成砂水 - 气 - 甲烷水合物样品的热性能

Methane hydrates (MHs) are present in large amounts in the ocean floor and permafrost regions. Methane and hydrogen hydrates are being studied as future ...

Screening for Endocrine Activity in Water Using Commercially-available In Vitro Transactivation Bioassays

In vitro transactivation bioassays have shown promise as water quality monitoring tools, however their adoption and widespread application has been hindered partly due to a lack of standardized methods and availability of robust, user-friendly technology. In this study, commercially available, division-arrested cell lines were employed to quantitatively screen for endocrine activity of chemicals present in water samples of interest to environmental quality professionals. A single, standardized protocol that included comprehensive quality assurance/quality control (QA/QC) checks was developed for Estrogen and Glucocorticoid Receptor activity (ER and GR, respectively) using a cell-based Fluorescence Resonance Energy Transfer (FRET) assay. Samples of treated municipal wastewater effluent and surface water from freshwater systems in California (USA), were extracted using solid phase extraction and analyzed for endocrine activity using the standardized protocol. Background and dose-response for endpoint-specific reference chemicals met QA/QC guidelines deemed necessary for reliable measurement. The bioassay screening response for surface water samples was largely not detectable. In contrast, effluent samples from secondary treatment plants had the highest measurable activity, with estimated bioassay equivalent concentrations (BEQs) up to 392 ng dexamethasone/L for GR and 17 ng 17&#946;-estradiol/L for ER. The bioassay response for a tertiary effluent sample was lower than that measured for secondary effluents, indicating a lower residual of endocrine active chemicals after advanced treatment. This protocol showed that in vitro transactivation bioassays that utilize commercially available, division-arrested cell &#34;kits&#34;, can be adapted to screen for endocrine activity in water.

Screening for Endocrine Activity in Water Using Commercially-available In Vitro Transactivation Bioassays

A protocol to screen for endocrine activity in organic extracts of water samples, including treated wastewater effluent and surface (receiving) water, was adapted using commercially available division-arrested ("freeze and thaw") in vitro transactivation bioassays.

在用水筛查内分泌活动市售的<em&gt;体外</em&gt;式激活生物测定

In vitro transactivation bioassays have shown promise as water quality monitoring tools, however their adoption and widespread application has been ...

Extraction of Organochlorine Pesticides from Plastic Pellets and Plastic Type Analysis

Plastic resin pellets, categorized as microplastics (&#8804;5 mm in diameter), are small granules that can be unintentionally released to the environment during manufacturing and transport. Because of their environmental persistence, they are widely distributed in the oceans and on beaches all over the world. They can act as a vector of potentially toxic organic compounds (e.g., polychlorinated biphenyls) and might consequently negatively affect marine organisms. Their possible impacts along the food chain are not yet well understood. In order to assess the hazards associated with the occurrence of plastic pellets in the marine environment, it is necessary to develop methodologies that allow for rapid determination of associated organic contaminant levels. The present protocol describes the different steps required for sampling resin pellets, analyzing adsorbed organochlorine pesticides (OCPs) and identifying the plastic type. The focus is on the extraction of OCPs from plastic pellets by means of a pressurized fluid extractor (PFE) and on the polymer chemical analysis applying Fourier Transform-InfraRed (FT-IR) spectroscopy. The developed methodology focuses on 11 OCPs and related compounds, including dichlorodiphenyltrichloroethane (DDT) and its two main metabolites, lindane and two production isomers, as well as the two biologically active isomers of technical endosulfan. This protocol constitutes a simple and rapid alternative to existing methodology for evaluating the concentration of organic contaminants adsorbed on plastic pieces.

Microplastics act as vector of potentially toxic organic contaminants with unpredictable effects. This protocol describes an alternative methodology for assessing the levels of organochlorine pesticides adsorbed on plastic pellets and identifying the polymer chemical structure. The focus is on pressurized fluid extraction and attenuated total reflectance Fourier transform infrared spectroscopy.

从塑料颗粒中提取有机氯农药和塑料类型分析

Plastic resin pellets, categorized as microplastics (&#8804;5 mm in diameter), are small granules that can be unintentionally released to the environment ...

Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events

The purpose of this study is to describe the methods used to capture flow-weighted water and suspended particulates from farm canals during drainage discharge events. Farm canals can be enriched by nutrients such as phosphorus (P) that are susceptible to transport. Phosphorus in the form of suspended particulates can significantly contribute to the overall P loads in drainage water. A settling tank experiment was conducted to capture suspended particulates during discrete drainage events. Farm canal discharge water was collected in a series of two 200 L settling tanks over the entire duration of the drainage event, so as to represent a composite subsample of the water being discharged. Imhoff settling cones are ultimately used to settle out the suspended particulates. This is achieved by siphoning water from the settling tanks via the cones. The particulates are then collected for physico-chemical analyses.

Nutrients present in particulate form can contribute significantly to the overall loads in agricultural drainage waters. This study describes a novel method to capture flow-weighted water and suspended particulates from farm canal drainage over the entire duration of the drainage event.

在排水过程中捕获农用运河中的流动加权水和悬浮颗粒

The purpose of this study is to describe the methods used to capture flow-weighted water and suspended particulates from farm canals during drainage ...

Construction of a Low-cost Mobile Incubator for Field and Laboratory Use

Incubators are essential for a range of culture-based microbial methods, such as membrane filtration followed by cultivation for assessing drinking water quality. However, commercially available incubators are often costly, difficult to transport, not flexible in terms of volume, and/or poorly adapted to local field conditions where access to electricity is unreliable. The purpose of this study was to develop an adaptable, low-cost and transportable incubator that can be constructed using readily available components. The electronic core of the incubator was first developed. These components were then tested under a range of ambient temperature conditions (3.5 &#176;C - 39 &#176;C) using three types of incubator shells (polystyrene foam box, hard cooler box, and cardboard box covered with a survival blanket). The electronic core showed comparable performance to a standard laboratory incubator in terms of the time required to reach the set temperature, inner temperature stability and spatial dispersion, power consumption, and microbial growth. The incubator set-ups were also effective at moderate and low ambient temperatures (between 3.5 &#176;C and 27 &#176;C), and at high temperatures (39 &#176;C) when the incubator set temperature was higher. This incubator prototype is low-cost (&lt; 300 USD) and adaptable to a variety of materials and volumes. Its demountable structure makes it easy to transport. It can be used in both established laboratories with grid power or in remote settings powered by solar energy or a car battery. It is particularly useful as an equipment option for field laboratories in areas with limited access to resources for water quality monitoring.

This paper describes a method for building an adaptable, low-cost and transportable incubator for microbial testing of drinking water. Our design is based on widely available materials and can operate under a range of field conditions, while still offering the advantages of higher-end laboratory-based models.

建造供野外和实验室使用的低成本移动孵化器

Incubators are essential for a range of culture-based microbial methods, such as membrane filtration followed by cultivation for assessing drinking water ...

Composition and Distribution Analysis of Bioaerosols Under Different Environmental Conditions

Variable microorganisms in particulate matter (PM) under different environmental conditions may have significant impacts on human health. In this study, we described a protocol for multiple analyses of the biological compositions in environmental PM. Five experiments are presented: (1) PM number monitoring by using a laser particle counter; (2) PM collection by using a cyclonic aerosol sampler; (3) PM collection by using a high-volume air sampler with filters; (4) culturable microbes collection by the Andersen six-stage sampler; and (5) detection of biological composition of environmental PM by bacterial 16SrDNA and fungal ITS region sequencing. We selected hazy days and a livestock farm as two typical examples of the application in this protocol. In this study, these two sampling methods, cyclonic aerosol sampler and filter sampler, showed different sampling efficiency. The cyclonic aerosol sampler performed much better in terms of collecting bacteria, while these two methods showed the same efficiency in collecting fungi. Filter samplers can work under low temperature conditions while cyclonic aerosol samplers have a sampling limitation for temperature. A solid impacting sampler, such as an Andersen six-stage sampler, can be used to sample bioaerosols directly into the culture medium, which increases the survival rate of culturable microorganisms. However, this method mainly relies on culture while more than 99% of microbes cannot be cultured. DNA extracted from the culturable bacteria collected by the Andersen six-stage sampler and samples collected by cyclonic aerosol sampler and filter sampler were detected by bacterial 16S rDNA and fungal ITS region sequencing.All the methods above may have wide application in many fields of study, such as environmental monitoring and airborne pathogen detection. From these results, we can conclude that these methods can be used under different conditions and may help other researchers further explore the health impacts of environmental bioaerosols.

Understanding the biological composition of environmental particulate matter is important for the study of its significant impacts on human health and disease spread. Here, we used three types of bioaerosol sampling methods and a biological analysis of airborne microbes to better explore airborne microbial communities under different environmental conditions.

不同环境条件下生物气溶胶的组成及分布分析

Variable microorganisms in particulate matter (PM) under different environmental conditions may have significant impacts on human health. In this study, ...

Xylem Water Distribution in Woody Plants Visualized with a Cryo-scanning Electron Microscope

A scanning electron microscope installed cryo-unit (cryo-SEM) allows specimen observation at subzero temperatures and has been used for exploring water distribution in plant tissues in combination with freeze fixation techniques using liquid nitrogen (LN2). For woody species, however, preparations for observing the xylem transverse-cut surface involve some difficulties due to the orientation of wood fibers. Additionally, higher tension in the water column in xylem conduits can occasionally cause artifactual changes in water distribution, especially during sample fixation and collection. In this study, we demonstrate an efficient procedure to observe the water distribution within the xylem of woody plants in situ&#160;by using a cryostat and cryo-SEM. At first, during sample collection, measuring the xylem water potential should determine whether high tension is present in the xylem conduits. When the xylem water potential is low (&#60; ca. &#8722;0.5 MPa), a tension relaxation procedure is needed to facilitate better preservation of the water status in xylem conduits during sample freeze fixation. Next, a watertight collar is attached around the tree stem and filled with LN2&#160;for freeze fixation of the water status of xylem. After harvesting, care should be taken to ensure that the sample is preserved frozen while completing the procedures of sample preparation for observation. A cryostat is employed to clearly expose the xylem transverse-cut surface. In cryo-SEM observations, time adjustment for freeze-etching is required to remove frost dust and accentuate the edge of the cell walls on the viewing surface. Our results demonstrate the applicability of cryo-SEM techniques for the observation of water distribution within xylem at cellular and subcellular levels. The combination of cryo-SEM with non-destructive in situ observation techniques will profoundly improve the exploration of woody plant water flow dynamics.

Observing the water distribution within the xylem provides significant information regarding water flow dynamics in woody plants. In this study, we demonstrate the practical approach to observe xylem water distribution in situ&#160;by using a cryostat and cryo-SEM, which eliminates artifactual changes in the water status during sample preparation.

木本植物的赛莱默水分布,用低温扫描电子显微镜可视化

A scanning electron microscope installed cryo-unit (cryo-SEM) allows specimen observation at subzero temperatures and has been used for exploring water ...