为研究含一氧化碳(carbon monoxide,CO)气调包装(modified atmosphere packaging,MAP)协同超高压对冷却猪肉杀菌护色的效果,利用含体积分数浓度为2％的CO气调包装协同超高压处理新鲜猪肉.结果表明:在0～400 MPa压力范围内,随着压力的增大亮度值L*不断增加,红度值a*逐渐变小,黄度值b*先变小后增大.200 MPa以上压力使肉颜色发白,即单独超高压处理给肉带来了色变,且压力越大色变越严重,300 MPa以上肉色变异不可接受.而含CO气调包装的协同可以提高a*值,掩盖部分色变.CO无杀菌效果,但有一定的抑菌效果,其协同超高压可以增加肉的贮藏期.总的来说2％CO协同300 MPa以内的压力可以在一定范围内对冷却肉有效杀菌的同时保证肉的颜色,且先充气包装后高压处理效果更显著.

[目的]研究高温灭菌协同不同压力的超高压处理对方便熟湿面食用品质的影响.[方法]将经过不同压力处理制成的熟湿面样品常温贮藏5 d,然后对其进行感官评分与复热烹煮品质测定,并用质构仪进行TPA试验,以测定超高压对面条的硬度、弹性、咀嚼性等指标的影响.[结果]高温灭菌协同超高压处理在使方便熟湿面可长期常温贮藏的前提下有效改善其食用品质,且处理压力控制在200～300 MPa时,熟湿面的综合食用品质最佳.[结论]该研究可为高温灭菌协同超高压在方便熟食面的生产提供指导.

This study was conducted to determine whether the application of high pressure processing (HPP) could prevent the process of rigor in fresh pork and to identify the physical and chemical changes occurring in the meat that are responsible for this effect. Pressure (0-400 MPa) and time (10 min) were applied to the pork loin and enzyme samples. The effects of treatment on shear force, myofibrillar fragmentation, enzyme activity and meat texture were measured. The results showed that, compared with untreated samples, HPP treatment inhibited the occurrence of rigor in pork. The myofibrillar fragmentation indices of HPP treated samples were higher than those of control samples and increased linearly with increasing pressure. Application of HPP prevented the process of rigor at 0-300 MPa, reduced calpain activity and markedly decreased calpastatin activity, resulting in an increase of total calpains. Above 300 MPa, the mechanical action of pressure led to continuous prevention of rigor.

This study was conducted to determine whether the application of ultrahigh pressure could modify the content of inosine 5′-monophosphate (IMP) in fresh pork and give direct detection of each relevant enzymatic activity to affirm the enzymatic mechanism. Pressure (0–400MPa) and time (10min) were applied to two types of samples: adenosine monophosphate deaminase, acid phosphatase, and alkaline phosphatase in normal saline and IMP in pork tenderloin. The results showed that varied degrees of susceptibility depended upon the pressure level. The pressure of 300MPa could promote the formation of IMP to 1250%, at which the activity of adenosine monophosphate deaminase, an enzyme catalyzing adenosine monophosphate (AMP) to IMP, was maximized. In contrast, the activities of acid phosphatase and alkaline phosphatase were suppressed at this extreme pressure, resulting in decomposition of IMP. Finally, IMP accumulated to its maximum level at 300MPa.

To achieve the commercial circulation of fresh dendrobium juice, high hydostatic pressure (HHP) technology was applied in its processing process. Fresh Dendrobium huoshanense juice with the solid-liquid ratio of 1:40 (g/mL) was processed under 300 MPa pressure for 15 min, its dissolution of polysaccharide and total alkaloid increased by 15.49％ and 3.49％ compared with that of untreated fresh juice, they ultimately reached 82.07±1.74 mg/g and 206.97±5.25 μg/g (in fresh weigh), respectively. As to dendrobium juice whether it was subjected to HHP treatment, the total alkaloid was digested in simulated gastric and intestinal fluids, and their release amount was almost equal. In addition, the bioavailability of total alkaloid using dialysis method was up to 77.34％±2.24％ in HHP processed juice, but untreated fresh juice only gave 68.30％±1.15％. Finally, HHP processed dendrobium juice could be stored at 4℃ for over six weeks, and its total bacteria, mould and yeast, coliforms conformed to the standards. The results showed that HHP treatment (300 MPa, 15 min) could effectively sterilize the microorganisms so as to prolong the storage period of Dendrobium huoshanense juice, it also promoted the dissolution of polysaccharide and the digestion and absorption of total alkaloid.

目的:利用热水协同超高压快速复鲜冷冻牛肉,抑制重结晶.方法:以汁液损失率、肉色以及硬度值为指标,通过单因素以及正交优化得出最优复鲜工艺.结果:当采用热水温度40℃,压力150 MPa,保压时间40 min时,与常压解冻后的冷冻牛肉相比汁液损失率降低了10％,硬度降低了50％,肉色与新鲜牛肉无显著(p＞0.1)色差.结论:按此复鲜工艺解冻复鲜后的牛肉显著(p＜0.05)降低了汁液损失率以及肉的硬度,提升了解冻速率,抑制了重结晶,具有广阔的市场前景.

In order to investigate the effect of high pressure combined with moderate temperature on the activity and allergenicity of pineapple juice,after treated by different pressures and temperatures,the proteolytic activity,fibrinolytic activity and allergenicity change of fresh squeezed pineapple juices were detected.The results showed that the effect of temperature on proteolytic activities were weaken and not significant under high pressure.The fibrinolytic activities increased under 400 MPa treatment combined with different temperatures,while decreased under 500 MPa treatment combined with a series of temperatures.Allergenicity decreased with the increase of pressure and temperature,and fell to 51.39％ at 500 MPa and 50 ℃.Therefore,the effect of high pressure combined with moderate temperature on proteolytic activity,fibrinolytic activity and allergenicity was different.Preserving activity and reducing allergenicity of pineapple juice could be achieved simultaneously with the selection of appropriate temperature and pressure.

目的:生产一种可常温贮藏、口感柔脆有韧性的高温卤制牛肚.方法:以硬度、脆性和咀嚼性为考察指标,通过超高压处理对牛肚进行改性.结果:经压力200 MPa、保压时间10min、蒸煮温度118℃、蒸煮时间10 min处理后,与未经处理的卤制牛肚相比,硬度和咀嚼性减小19.36％和27.46％,脆性提高了9.06％.结论:在保证商业无菌的前提下,超高压处理可以明显改善高温卤制牛肚的柔脆口感.

In order to simultaneously preserve fibrinolytic activity and reduce allergenicity of pineapple juice,effects of pressure,temperature,pH and added amount of NaC1 were investigated.Based on single factor experiments,Box-Behnken experimental design and response surface methodology were used to optimize the processing.The optimal parameters were obtained to be pressure of 425 MPa,temperature of 50 ℃C,pH 3.22 and NaC1 of 0.55％.With these conditions,the remaining fibrinolytic activity of pineapple juice was 88.34％ and the allergenicity was decreased to 33.71％.The results indicated that this processing could effectively retain fibrinolytic activity and reduce allergenicity of pineapple juice.

[Objective] In order to ensure pork tendon and pigskin all cooked well.[Method] The raw pig's trotters were taken ultra-high pressure treatment to lower the cooking temperature.[Result] The results showed that,when the pressure was 300-400 MPa,the treatment time was 10-20 min,the pigskin and pork tendon would be all cooked well when the temperature was 121 ℃ and the heating time was 10 min,and the products satisfied the commercial sterile national standard.[Conclusion] Ultra-high pressure processing can enhance the boiling resistance of pigskin and reduce the aging temperature of pork tendons,ensure the pork tendon and pigskin all cooked well in the high temperature cook processing.

[Objective] The research aimed to study the effect of ultra-high pressure treatment on the digestion characteristics of germinated brown rice.[Method] With the self-made germinated brown rice as raw material,the effects of different treatment pressure and different storage time on the digestibility of germinated brown rice were analyzed by simulating the in vitro digestion of brown rice starch.[Result] Ultrahigh pressure could increase the digestion rate of germinated brown rice and had a higher digestion rate at 300.0 MPa.The content of fast digestible starch(RDS) and resistant starch (RS) in germinated brown rice were 64.32％ and 7.29％ respectively,untreated group was 55.41％ and 11.86％;Deposit 2 days later,the content of RDS at 400.0 MPa was 61.43％ much higher than 47.47％ of the untreated group,the RS starch content was 8.50％ less than 16.68％ of the untreated group,but slightly higher than the fresh rice.[Conclusion] Ultra-high pressure treatment can enhance the digestibility of germinated brown rice,increase the content of RDS,reduce the content of RS,increase the digestibility,inhibit the retrogradation,thereby to enhance the quality of germinated brown rice.

In order to extend the shelf time of low-salt pickled lettuce by sterilization without destroying its texture,use the texture and main pathogenic microorganisms as the indicators,the optimal ultra-high pressure (UHP)process conditions are studied.The results show that E. coli and Staphylococcus aureus are all killed under the conditions of pressure 300 MPa,holding time 10 min. Under such conditions,the hardness and brittleness of product is significantly improved than the heat-treated sample,and the product could be well stored for 10 days at 25 ℃.The results indicate that the low-salt pickled lettuce could be effective sterilized by UHP treatment,and its texture is maintained well in the meantime.

Conjugated linoleic acid(CLA), a mixture of positional and geometric isomers of linoleic acid with conjugated double bonds, has attracted considerable attention since cis-9, trans- 11-CLA(c9, t11-CLA) and trans-10, cis-12-CLA(t10, c12-CLA) have a great application potential in medicines, foods and health produ cts based on anticancer, immune regulatory, anti-atherosclerosis, anti-obesity and antioxidant activities. In this study, Kunming mi ce were used as experimental subjects to evaluate the inhibitory effect of CLA(80% purity, containing 36.40% c9, t11-CLA, 36.26% t10, c12-CLA and 7.14% other CLA isomers) on the obesity of mice. The tested mice were divided into obesity model control group, normal control group and CLA treatment group, and the mice in the CLA treatment group were administered with CLA by gavage for six weeks, and then obesity indexes, such as body weight, Lee’s index, total weight of fat, fatty coefficient, and total cholesterol(TC), triglyceride(TG), low density lipoprotein cholesterol(LDL- C), high density lipoprotein cholesterol(HDL-C) in serum, fatty acid synthase(FAS) in liver and viscera of the mice, were measured. The results showed that the obesity indexes, including Lee’s index, fatty coeffi cient, TC, TG and LDL-C, in the CLA treatment groups at various dosages were signifi cantly lower than the obesity model control group(P < 0.05 or P < 0.01), and HDL-C was signifi cantly higher than the obesity model control group(P < 0.01). Lee’s index, fatty coeffi cient, TC, TG, and LDL-C decreased with increasing CLA dose, while HDL-C increased. High-dose CLA(0.15 m L/10 g) could control the obesity indexes of obesity model control group to the level of the normal control group, and CLA treatment at each dose had no signifi cant effect on the viscera of the mice; therefore, CLA cou ld inhibit obesity and had no toxic side effect on the growth of mice. The Lee’s index, fatty coefficient, TC, TG, and LDL-C had high positive correlation with FAS, while HDL-C had a highly negative correlat ion. An obvious correlation between FAS and obesity index was observed and it was further confi rmed that FAS is the potential target of obesity. CLA treatment can signifi cantly reduce FAS(P < 0.01), and this could be the mechanism of its antiobesity effect.

目的 设计合成丹参素脑靶向衍生物,并研究其在大鼠体外血浆和脑匀浆中的代谢.方法 将四甲基吡嗪及其衍生物作为载体引入丹参素设计脑靶向衍生物,借助计算软件对化合物的脂水分配系数、脑血浓度比、P-糖蛋白亲和力等参数进行预测,筛选出较优化合物DT3进行化学合成;采用HPLC-UV测定DT3及中间产物DT1在大鼠血浆和脑匀浆中的降解情况.结果 制备了两种丹参素-吡嗪酯类衍生物——DT1和DT3;建立了DT3、DT1和羟甲基川芎嗪在大鼠血浆和脑匀浆中同步检测方法;DT3在血浆和脑匀浆中均经历DT3→DT1→活性代谢物过程;DT3在血浆中降解相对于DT1有所减缓,其羟甲基川芎嗪的t1/2分别为1.71和1.68 min;DT3在脑匀浆可快速代谢出羟甲基川芎嗪,且浓度呈现平稳增加,t1/2达222.88 min.结论 本实验设计合成的丹参素-吡嗪酯类衍生物DT3延长了血浆t1/2,同时能在脑匀浆快速降解出活性代谢物.

目的:借助超高压处理改善降脂蛋黄酱的黏性、分散性与稳定性.方法:以黏度、中位径以及离心破乳率为指标,通过单因素以及正交优化得出最优试验条件.结果:当采用处理条件为压力400 MPa、保压时间10 min时,蛋黄酱加油量可降到50％,较未处理样品黏度可提高超过5倍,分散性可提高14.5％,稳定性可提高90.7％,并具有更优的感官特性.结论:超高压在保证安全的前提下,使降脂蛋黄酱加油量降低到50％,显著改善了降脂蛋黄酱的黏性、分散性、稳定性以及感官特性,具有广阔的应用前景.

The effects of ginkgolide B derivative (GBD) and GB on P-glycoprotein efflux function and expression level were studied to explain GBD's brain-targeting behavior.

Conjugated linoleic acid(CLA) has wide application potential in medicine,food,and health products,because of its anticancer,immune regulatory,anti-atherosclerosis,antiobesity,and antioxidant activities.Currently,commercial CLA is typically produced through alkali isomerisation using sunflower oil as raw material,generating a mixture of CLA with undesirable isomer by-products.Use of CLA for nutraceutical and medicinal purposes requires safe isomer-selective synthesis.Hence,CLA biosynthesis naturally attracted much attention because of its specificity and safety.The aim of the present study was to isolate and identify Lactobacillus strains from the fermented pickle brines,which can convert linoleic acid(LA) into CLA under aerobic conditions.Using serial dilutions and plate streaking in de Man Rogosa Sharpe(MRS) agar medium under aerobic conditions,16 CLA-producing Lactobacillus strains were isolated,among which PC-3 exhibited the highest production of CLA.Based on analyses using SEM,API-50 CHL,and 16 S r RNA gene sequencing,PC-3 was identified as Lactobacillus plantarum.The 16 S r DNA gene sequence(1460bp)was submitted to Gen Bank under the accession number JX270774.1.

The objective of this work was to identify the main allergenic proteins and to assess the influence of high hydrostatic pressure on the potential allergenicity of high hydrostatic pressure pineapple juice. Fresh pineapple juice was treated with different pressures and the allergenic proteins were extracted and analyzed by sodium dodecyl sulfate polyacrylamide gel electropheresis, Western bloting and liquid chromatography-tandem mass spectrometry. The main allergenic proteins were detected as 24-kDa and 14-kDa bands by serum of pineapple-allergic patients. liquid chromatography-tandem mass spectrometry analysis of these bands showed that they actually consisted of a mixture of several isotypes of cysteine proteinases. Among these, bromelain (Ananas comosus) is a known allergen named Ana c 2 and it is highly homologous to other cysteine proteinases. Enzyme-linked immunosorbent assay assay of high hydrostatic pressure pineapple juice carried out at ambient temperature (18-22 degrees C) showed that the higher the pressure, the higher the reduction in allergenicity, yielding a maximum reduction of about 20% under 500 MPa. However, in the case of 400 MPa and 50 degrees C, the reduction rate of allergenicity was higher, up to 50% compared to that of the sample at 20 degrees C without high hydrostatic pressure treatment. Taken together, the results suggested that high-pressure treatment could alter the potential allergenicity of pineapple juice allergens and identified Ana c 2 and a few other related cysteine proteinases as the main allergens.

为了明确超高压加工技术对纤维素酶活性的影响,分别研究了压力、保压时间、温度、乙醇体积分数、加压次数和pH值等对蛹虫草汁中纤维素酶的羧甲基纤维素酶活性(CMC)和滤纸酶活(FPA)的影响.结果表明,纤维素酶的最适压力、保压时间、温度、乙醇体积分数、pH值和加压次数分别为:400 MPa、10 min、35℃、30％,pH 4.0～7.0,加压1次,在最适条件下,CMC酶活比处理前分别提高了82.07％、52.41％、87.22％、54.48％、67.52％和66.67％;FPA酶活比处理前分别提高了97.37％、61.4％、69.4％、61.4％、1.31％和33.91％.因此,利用超高压处理能有效提高蛹虫草汁中的纤维素酶活性.

为了抑制陈米方便米饭的回生现象,试验以消减值为考察指标,采用正交试验优化超高压处理陈米方便米饭工艺条件,并考察陈米消减值最低时米饭中直链淀粉重结晶度变化情况.结果表明,当压力400 MPa,时间15 min,温度50℃时,超高压陈米消减值最低,其消减值为1 368cp,较未处理陈米降低了42.47％,差异显著,且陈米方便米饭的碘蓝值经此超高压条件处理后从0.223升高至0.384,超高压降低了直链淀粉的重结晶程度.通过调整超高压处理条件,可以明显降低陈米消减值,进而影响直链淀粉的重结晶,部分抑制了陈米方便米饭的回生.