北美海蓬子的真空渗透脱盐方法研究

以含盐量、叶绿素含量、VC含量为指标参数,对北美海蓬子脱盐脱水后感官进行评定,探索北美海蓬子真空渗透脱盐的技术指标.试验结果表明,采用漂烫6 min,水料比15∶1,真空渗透脱盐6 h,既能在最短时间内达到脱盐的目的,又能最大限度地保持产品品质,最终脱盐后北美海蓬子干基含盐率4.82%,叶绿素含量2.21 mg/g,VC含量49.85 mg/100 g.     

不同真空干燥温度对海南番木瓜粉香气成分SPME/GC-MS分析的影响

运用顶空固相微萃取结合气质联用技术对不同温度下真空干燥制得的番木瓜粉中香气成分进行分析。结果表明:共确定了121种挥发性成分,主要包括醇、酸、酮、酯、醛、烃等化合物。芳樟醇相对含量在室温(25℃)干燥时最高,为14.382%,但在真空热干燥条件(大于室温,50~100℃)下未检出;乙酸的相对含量会随着干燥温度的升高而升高;大部分酮类物质在25℃和60℃干燥时相对含量最高;在25℃下干燥的产品中异硫氰酸苄酯的相对含量高达34.617%,但在真空热干燥条件下均未检出;真空热干燥会使一些具有不良气味的醛类如糠醛、5-羟甲基糠醛的相对含量升高。     

干燥过程对海参内脏功能成分含量的影响

干燥过程是海产品加工中的一个关键环节,以含水量、海参总皂苷和海参黏多糖作为检测指标,比较鼓风干燥技术和真空干燥技术对海参功能成分的影响.鼓风干燥技术获得的产品中功能活性的含量略低于真空干燥技术样品,但是干燥时间短,能耗低.鼓风干燥技术烘干效果优良、成本低廉,可以适应大规模生产应用的需要.     

Insecticidal efficacy of phosphine fumigation at low pressure against major stored-product insect species in a commercial dried fig processing facility

We investigated the application of phosphine at low pressure for various exposure durations against major stored-product insects in a commercial dried fig processing facility in Central Greece. Trials were carried out inside a chamber, in which phosphine, in the form of aluminium phosphide pellets, was introduced with the use of a phosphine generator. The generator unit was also equipped with a vacuum pump to achieve low pressure inside the chamber. The chamber was filled with pallets with boxes containing figs. The insects tested were Tribolium confusum (all life stages), Ephestia elutella (eggs and larvae), Sitophilus oryzae (adults), Sitophilus granarius (adults), Rhyzopertha dominica (adults), Oryzaephilus surinamensis (adults) and Prostephanus truncatus (adults). Moreover, wheat grains containing immature stages of S. oryzae were also used. All insect-life stage combinations were exposed to phosphine at low pressure for 18, 48 and 72 h. In most cases, significant differences in mortality of insects treated with phosphine at low pressure compared to the control treatments were recorded. However, complete control (100%) was recorded only in the case of O. surinamensis adults and T. confusum larvae after exposure for 48 and 72 h, respectively. We conclude that the combined application of phosphine and low pressure at short exposure durations (up to 72 h) cannot provide sufficient control at least against the stored-product insect species and life stages tested in the present study.     

真空制脯技术的研究

本文论述了在果脯制作过程中,采用真空渗糖取代旧工艺的糖煮,井且改浸糖抽空为喷糖抽空,以及增加一道没有抽空液的空抽工序和涮糖工序,同时在浸糖前后利用温差加强渗糖的综合速制果脯的新工艺.指出由这种新工艺制作的果脯,色、香、味、型、营养均优于旧工艺制作的果脯,配方合理,甜酸适口,在真空中能连续化机械生产,省工、省料,成本低,利润大。     

冻干草莓的工业化生产工艺研究

以干燥面积为250 m2的JDG-230型真空冷冻干燥生产线为实验平台, 以提高冻干草莓产品质量和经济效益为目标,对冻干草莓生产的工艺参数进行了工业化生产试验,结果表明:①工业化生产适宜工艺参数为:装盘量10.5 kg/m2、速冻温度-30℃、速冻时间2.5 h、升华干燥时干燥仓压力110～130 Pa、干燥解析时干燥仓压力30～50 Pa、解析时的物料温度45～50℃;②获得可应用于大工业化生产控制的草莓冻干过程曲线.     

升华干燥理论的研究

本文从理论上以及通过数学求解，得出升华干燥过程应属传质调控，即在真空状态下，使预先冻结的物料中的水分不经冰的融化直接以冰态升华为蒸汽被传出，从而使物料得以干燥。     

负压空化法提取虾青素

对负压空化法提取虾青素的各项工艺条件进行了初步探讨,研究了负压空化法提取的溶剂、溶剂质量分数、时间、通气量对虾青素提取效果的影响。得出最佳提取工艺参数为:提取溶剂为质量分数80%的乙醇溶液、提取时间为35min、通气量为0.2m3/h。并且对提取前后法夫酵母细胞的形态进行了显微观察,得到了显微照片。     

汽车真空助力器性能测试装置的研制

本文从汽车真空助力器的工作原理出发,利用80C51单片机完成了汽车真空助力器性能测试装置的数据采集、数据处理、测试结果显示和控制系统的软硬件设计.根据汽车真空助力器在各种工作条件下控制驱动装置的动作.完成了汽车真空助力器密封性、输入-输出特性、空行程等主要性能指标的测试.