眼临界充体萃取过程的优化选择

在对超临界流体技术概述的基础上,就影响萃取效率的诸多因素,如预处理方式、萃取温度、压力、ＣＯ２流量、萃取时间、夹带剂、分离压力、温度作了系统的综述,有助于更好的组织超临界流体提取实验,获得物料最佳的萃取条件。     

超临界CO2纯化辣椒色素的研究

研究了用超临界ＣＯ２流体纯化溶剂法提取辣椒色素的方法．用超临界ＣＯ２流体作萃取剂，从液体或固体物料中实现萃取、分离和纯化物料从而制备高纯度辣椒色素是可行的．使产品符合ＦＡＯ／ＷＨＯ残留溶剂标准要求（已烷含量２５ｍｇ／ｋｇ）的最佳工艺参数是：萃取压力１８ＭＰａ，萃取温度２５℃，萃取剂流量２．０Ｌ／ｍｉｎ，萃取时间３ｈ．     

超临界二氧化碳富集提纯鱼油中EPA和DHA的研究进展（I）

鱼油中的特征脂肪酸ＥＰＡ（甘二碳六烯酸）对人体的医疗保健作用受到越来越广泛的重视。综述了近年来人们对超临界二氧化碳（ＳＣ－ＣＯ２）与鱼油脂肪酸相平衡的研究概况，分析了温度、压力、夹带刺等对ＳＣ－ＣＯ２从鱼油脂肪酸混合物中萃取提纯ＥＰＡ和ＤＨＡ的影响。     

超临界二氧化碳富集提纯鱼油中EPA和DHA的研究进展（Ⅰ）──超临界二氧化碳与鱼油脂肪酸的相平衡研究

鱼油中的特征脂肪酚ＥＰＡ（廿碳五烯酸）和ＤＨＡ（廿二碳六烯酸）对人体的医疗保健作用受到越来越广泛的重视。综述了近年来人们对超临界二氧化碳（ＳＣ－Ｃ０２）与鱼油脂肪酸相平衡的研究概况，分析了温度、压力、夹带剂等对ＳＣ－ＣＯ２从鱼油脂肪酸混合物中萃取提纯ＥＰＡ和ＤＨＡ的影响。     

植物油品种鉴别方法的研究─—分光光度法

采用饱和Ｎａ２ＣＯ３溶液，对芝麻油等六种植物油进行萃取，测定提取液的５００ｎｍ～２４０ｎｍ吸收曲线，各种油脂的吸收谱图存在显著差异，依此进行油脂品种鉴别及掺伪油脂的分析。     

超临界CO2萃取茶籽油

提出了用超临界ＣＯ２萃取茶籽油的方法，考察了压力、温度对茶籽油在ＣＯ２中溶解度的影响，分析了萃取条件与油品质量的关系，并综合得到了超临界ＣＯ２萃取茶籽油的最佳萃取条件。     

超临界CO_2萃取法从月见草种子和丝状真菌中提取含γ－亚麻酸油脂

本文研究了用超临界ＣＯ_２从月见草种子和丝状真菌中提取含γ－亚麻酸油脂时，物料水分、粉碎粒度以及萃取条件（压力／温度）对萃取过程的影响。进一步探讨了对萃取成分进行选择分离的方法。     

超临界CO2萃取辣椒红色素的研究

本文着重研究了以传统溶剂萃取法得到的辣椒油树脂为原料，以无毒、易得、价廉的ＣＯ２为萃取剂，采用超临界萃取的方法提取辣椒红色素。通过对萃取压力、萃取温度、萃取时间、ＣＯ_２流量等条件的试验，获得了最佳的工艺参数。试验结果表明，超临界萃取法具有工艺简单、操作安全、产品质量好、萃取效率高等优点。     

超临界CO2萃取法从月见草种子和丝状真菌中提取含γ—亚麻酸油脂

本文研究了用超临界ＣＯ２从月见草种子和丝状真中提取含γ－亚麻酸油脂时，物料水分、粉碎粒度以及萃取条件（压力／温度）对萃取过程的影响。进一步探讨了对萃取成分进行选择分离的方法。     

以光卤石为原料制取磷酸二氢钾的工艺

以天然光卤石为原料生产ＫＨ２ＰＯ４,提出了最佳工艺条件．采用高氯酸铵（ＮＨ４ＣｌＯ４）加入光卤石饱和溶液,经沉淀、过滤得高氯酸钾（ＫＣｌＯ４）,再将此ＫＣｌＯ４ 加入磷酸中,以叔胺类萃取剂萃取去除高氯酸（ＨＣｌＯ４）获得ＫＨ２ＰＯ４．萃出的ＨＣｌＯ４ 经氢氧化铵水溶液反萃所得的ＮＨ４ＣｌＯ４ 可循环使用．光卤石中钾的回收率达９４％ ,所得ＫＨ２ＰＯ４ 的纯度为９９．１％ ．     

大米蛋白渣除脂方法的研究

探究大米蛋白渣除脂的方法和条件。以余脂、油脂提取率为评价指标,分别采用密度分离法、溶剂复合法、超临界CO2萃取法对米渣中油脂进行萃取分离。结果表明密度分离法脱脂效果最差;溶剂复合法脱脂效果较好,油脂提取率达85.12%;超临界CO2萃取的脱脂效果最好,其最佳条件为:萃取温度45℃、萃取压力25MPa、萃取时间60min、夹带剂无水乙醇用量200mL,油脂提取率可达98.62%。     

不同提取方法对新疆薄皮核桃油酸价和过氧化值的影响

探讨不同提取方法对新疆薄皮核桃油酸价和过氧化值的影响。分别采用索氏抽提有机溶剂(石油醚)法、超临界CO_2萃取法、冷榨法提取薄皮核桃油,用容量分析法测定油脂中的酸价和过氧化值,并比较三种方法提取的油脂的氧化稳定性。结果表明,提取方法对核桃油脂的色泽、气味、氧化稳定性影响较大。索氏抽提法操作简便、成本低,但得到的核桃油脂有溶剂残留,需脱溶,且提取时间较长。超临界CO_2萃取精密度可靠,得到的油脂品质和纯度高,但生产成本高。结合实际生产,冷榨法更适合用于核桃油的提取。     

顶空-气相色谱-质谱法分析牡丹鲜花精油中的挥发性成分

选用TG-5MS毛细管柱作为色谱分离柱,并采用顶空-气相色谱-质谱法分析由超临界CO2流体萃取、亚临界流体萃取、水蒸气蒸馏、有机溶剂萃取4 种方法制得的6 种凤丹牡丹精油中的挥发性成分,共鉴定出32 种挥发物,包括芳香烃类、醇类、酯类、烷烃类、醚类、酮类、醛类7 类物质,不同精油挥发物组成及相对含量均有明显差异,共有成分为1,3,5-三甲氧基苯、γ-壬内酯和十六烷,且1,3,5-三甲氧基苯在6 种牡丹精油中的相对含量均最高。超临界CO2流体萃取的牡丹精油花香浓郁,得率最高,适宜制备牡丹精油;水蒸气蒸馏提取的牡丹精油得率最低,但其天然香味物质最丰富,适宜制备牡丹花水。     

Oil Absorption During Frying of Frozen Parfried Potatoes

A tracer method was used to assess the uptake of oil by commercial frozen parfried potatoes fried (180 °C, 150 s) in colza oil (CO) involving a short post-frying immersion in hot coconut fat (CF). CO and CF were determined directly in the crust by differential scanning calorimetry (crystallization temperature and enthalpy −42.7 °C/50 J/g and 10 °C/71 J/g, respectively). Oil uptake by the crust during frying in CO or CF was similar (average 25.3%). Potato samples transferred immediately after frying in CO to the CF bath had most of the CO absorbed replaced by CF after a 10 s post-frying, meaning that CO was readily accessible in the crust structure. Samples fried in CO and cooled for up to 60 s before transfer to hot CF showed only partial replacement of CO. Oil wetting the surface of the sample at the end of frying was estimated as 70 to 80% of the total oil uptake. Formation of the crust (frying time > 1 min) was required for oil to migrate into intercellular spaces that are dynamically formed during frying and thus accessible to CF and solvents.     

异丙醇提取稻米油动力学特性

采用溶剂浸出法从米糠中提取油脂,以提油率为指标,对不同工艺条件下稻米油提取过程进行动力学分析,研究溶剂、料液比、提取温度以及辅助处理方法对米糠提油率的影响。结果表明：稻米油提取过程符合菲克第二定律,且该动力学方程能较为准确地模拟溶剂法提取稻米油的过程;提取条件不同时,提油率及提取速率差异较明显。相比无水乙醇和正己烷,异丙醇作为提取溶剂时,米糠总提油率Me和传质系数k均较高。适当地增加溶剂用量、提高提取温度以及动态处理均有助于提高总提油率和传质系数。动态处理增大了油脂扩散的传质驱动力,以异丙醇为溶剂,在提取温度为50 ℃、料液比为1∶7.5、动态处理的条件下,米糠提油率达到90.12%,比静态处理提高了0.54 倍,最大有效扩散系数达到5.172 6×10―12 m2/s。     

花椒风味成分的提取

对比研究了用有机溶剂和超临界CO2 提取花椒风味成分的方法 ,结果表明 :无水乙醚是提取花椒风味成分 (香气和麻味 )的最适宜的有机溶剂 ,超临界CO2 提取花椒风味成分的效果明显优于有机溶剂法 ,其最佳提取工艺条件为 ,原料粒度 40目 ,萃取时间 2h ,流量 2 5kg/h ,温度 45℃ ,压力 3 2MPa ,油树脂得率可达 12 63 %。     

不同方法提取胡麻油性质的对比研究

采用Schaal烘箱法对不同方法提取的胡麻油的氧化性质进行了对比研究。试验结果表明:由3种方法提取的胡麻油的自氧化试验可知,过氧化值变化由大到小为冷榨胡麻油、超临界CO2提油、溶剂提油。碘值变化从大到小的顺序为超临界提油、冷榨胡麻油、溶剂提油;酸值变化从大到小的顺序为超临界提油、溶剂提油、冷榨胡麻油;黏度变化从大到小的是超临界提油、冷榨胡麻油、溶剂提油。3种胡麻油中特征值变化最大的是超临界CO2提取的胡麻油。     

Effect of temperature of CO2 injection on the pH and freezing point of milks and creams

The objectives of this study were to measure the impact of CO2 injection temperature (0 degree C and 40 degrees C) on the pH and freezing point (FP) of (a) milks with different fat contents (i.e., 0, 15, 30%) and (b) creams with 15% fat but different fat characteristics. Skim milk and unhomogenized creams containing 15 and 30% fat were prepared from the same batch of whole milk and were carbonated at 0 and 40 degrees C in a continuous flow CO2 injection unit (230 ml/min). At 0 degree C, milk fat was mostly solid; at 40 degrees C, milk fat was liquid. At the same total CO2 concentration with CO2 injection at 0 degree C, milk with a higher fat content had a lower pH and FP, while with CO2 injection at 40 degrees C, milks with 0%, 15%, and 30% fat had the same pH. This indicated that less CO2 was dissolved in the fat portion of the milk when the CO2 was injected at 0 degree C than when it was injected at 40 degrees C. Three creams, 15% unhomogenized cream, 15% butter oil emulsion in skim milk, and 15% vegetable oil emulsion in skim milk were also carbonated and analyzed as described above. Vegetable oil was liquid at both 0 and 40 degrees C. At a CO2 injection temperature of 0 degree C, the 15% vegetable oil emulsion had a slightly higher pH than the 15% butter oil emulsion and the 15% unhomogenized cream, indicating that the liquid vegetable oil dissolved more CO2 than the mostly solid milk fat and butter oil. No difference in the pH or FP of the 15% unhomogenized cream and 15% butter oil emulsion was observed when CO2 was injected at 0 degree C, suggesting that homogenization or physical dispersion of milk fat globules did not influence the amount of CO2 dissolved in milk fat at a CO2 injection temperature of 0 degree C. At a CO2 injection temperature of 40 degrees C and at the same total CO2 concentration, the 15% unhomogenized cream, 15% vegetable oil emulsion, and 15% butter oil emulsion had similar pH. At the same total concentration of CO2 in cream, injection of CO2 at low temperature (i.e., < 4 degrees C) may produce a better antimicrobial effect during refrigerated shelf life due to the higher concentration of CO2 in the skim portion of the cream.     

超临界CO_2萃取黄瓜籽油

应用超临界CO2萃取技术提取了黄瓜籽油。采用正交试验,考察了萃取压力、萃取温度、萃取时间及CO2流量对黄瓜籽油收率的影响。利用GC-MS分析了所得黄瓜籽油的脂肪酸组成。结果表明:影响黄瓜籽油收率的顺序为萃取压力>萃取温度>萃取时间>CO2流量;最佳萃取条件为压力35 MPa,温度35℃,时间120min,CO2流量45 L/min,在此条件下出油率可达26%。黄瓜籽油中含有4种脂肪酸,亚油酸含量高达77.81%。     

超声波法提取猕猴桃籽油工艺研究

通过超声波技术提取猕猴桃籽油工艺研究,探讨不同提取剂,提取剂用量、提取时间、次数及超声波功率对提取效果影响;采用正交法确定最佳工艺条件:超声波功率250W,石油醚作为提取剂、物料比1:8、提取2次,每次20 min。