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101.
D. K. Antala A. K. Varshney P. R. Davara V. P. Sangani 《Packaging Technology and Science》2015,28(6):557-564
Fully matured fresh guava fruits (Lucknow‐49) were precooled at 10 °C for 1 h and pretreated with 500‐ppm benomyl for 5 min. The fruits were packed in 25‐µm and 50‐µm LDPE bags with active modified atmosphere packaging of 3% O2 + 5% CO2, 6% O2 + 5% CO2 and 9% O2 + 5% CO2 gas concentrations and stored at 5 ± 1 °C and 10 ± 1 °C temperatures as well as non‐packaged as control. The shelf life of guava could be increased up to 42 days by packaging in 50‐µm LDPE bags with a gas concentration of 9% O2 + 5% CO2 and stored at 10 °C without much change in physical, biochemical and sensory characteristics. Physico‐chemical changes viz., PLW, pulp to peel ratio, firmness, TSS, total sugar, ascorbic acid and titratable acidity were observed minimum for fruits packed in 50‐µm LDPE bags at 3% O2 + 5% CO2 gas concentration at 5 °C storage temperature, but sensory score decreased drastically after 21 days of storage. Chilling injury was observed for the fruits packed at 5 °C storage temperature after 21 days of storage, and it was severe in 25‐µm LDPE bag at later stage. Control fruits over‐ripened with the highest weight loss (12.47%) on 6 days of storage and discarded from the storage. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
102.
Use of Sodium Lactate and Modified Atmosphere Packaging for Extending the Shelf Life of Ready‐to‐Cook Fresh Meal
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D. Gammariello A. L. Incoronato A. Conte M. A. Del Nobile 《Packaging Technology and Science》2015,28(2):101-112
In this work, the combined effects of sodium lactate and modified atmosphere packaging (MAP) in extending the shelf life of a ready‐to‐cook fresh skewer, made up of raw pork chops and semi‐dried vegetable mix (i.e. zucchini, peppers and tomatoes), were investigated. In the first experimental step, a sodium lactate solution was used to dip pork chops at three different concentrations: 20, 40 and 60% w/w. The second part of the work was focused on the use of MAP. In particular, the following MAPs were tested: MA1 (50%O2/30%CO2/20%N2), MA2 (70%O2/30%CO2), MA3 (30%O2/70%CO2) and MA4 (30%O2/30%CO2/40%N2). Finally, the optimal concentration of sodium lactate and the best gas composition were combined. The samples were stored at 4 °C; their microbial and sensory qualities were monitored along the entire observation period. The results indicate that the shelf life of the investigated ready‐to‐cook meal can be extended by approximately 83%, if compared with the control skewer packaged in air. The best preservation strategy is the combination of dipping of meat pieces in 40% sodium lactate solution and packaging under MA1. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
103.
104.
校企合作是高职专业教育发展的基础。只有让企业走进高职院校,让学生与教师走进企业,才能实现共同获利。让高职教学质量提高,学生轻松就业,企业拥有优秀的人才。但是校企合作不能表面化。高职院校要真正实现校企合作,要为企业展现合作将给企业带来的效益。要进行看得见摸得着的,切实可行的合作方案。本文主要就如何实现校企之间的合作,把校企合作落实到实处进行了研究。 相似文献
105.
《Food Control》2015
This study was conducted to investigate the antibacterial effects of various essential oils (EOs) against pathogens using the disc volatilization method. Also, combined effects of EOs in vapor phase and MAP were evaluated for reducing levels of total mesophilic microorganisms on fresh cabbage. The vapor phase activities of EOs (thyme-1, oregano-1, lemongrass-1, and lemongrass-2 oils) observed strong inhibitory effects. The MAP results showed that 100% CO2 gas packaging reduced significantly levels of total mesophilic microorganisms on cabbage and radish sprouts, and their reduction level was 1.55 and 2.26 log10 CFU/g compared to control after 21 days of storage (p ≤ 0.05). Based on previous results, combined effects of EOs in vapor phase and MAP (100% CO2) showed that lemongrass-2 oil with 20 discs showed complete inactivation by <1.0 log10 CFU/g after 14 days of storage. These results could provide useful information for developing alternative preservation method to improve the freshness and shelf-life of fresh produce using natural antimicrobials. 相似文献
106.
以广西白色强膨胀土为研究对象,利用MATLAB软件编制程序对土体裂隙图片进行二值化处理,获得裂隙率与含水率的线性回归关系。现场试验观测表明,雨季前裂隙长期平均宽度0.005 m,利用等效模型,获得表层土体含水率与裂隙间距的相关关系。按照雨水在裂隙中渗流的过程建立裂隙影响下的雨水入渗计算模型,利用不同裂隙间距,来描述裂隙分布。基于裂隙描述的雨水入渗膨胀土堑坡稳定性计算结果表明,是否考虑裂隙对膨胀土边坡稳定性的计算结果影响较大。当裂隙率较高时边坡持续降雨后安全系数会大幅度降低,同时边坡大气剧烈影响深度的加深也会引起安全系数的迅速降低。根据研究结果,对膨胀土边坡治理提出了具体建议。 相似文献
107.
Effect of microwave radiation on processing characteristics of sulphide minerals in inert atmosphere
N. Metin Can 《分离科学与技术》2016,51(7):1248-1258
The influence of microwave radiation on sulphide minerals in inert atmosphere has been investigated with respect to their processing characteristics such as magnetic susceptibility and floatability. Pure sulphide mineral samples were prepared in different size fractions. Microflotation tests were performed and magnetic susceptibilities of samples were measured after treating with microwave energy in inert atmosphere at three power levels for six time intervals. Possible modifications on the mineral surfaces due to microwave energy and exposure time were evaluated by XRD and optical microscopy. The results showed that selective separation of sulphide minerals in terms of floatability and magnetic separation could be possible. 相似文献
108.
109.
为了对CO2和H2O两种气氛的脱碳效果进行对比,将碳质量分数约为4.2%的Fe-C合金薄带分别在两种气氛中进行脱碳处理。通过热力学分析结合试验保证碳被脱除且铁不氧化的气氛条件分别为:Ar-CO-CO2(气体流量为850 mL/min,CO的体积分数为25%,$P_{CO_2}$/(PCO+$P_{CO_2}$)为0.26),Ar-H2-H2O(气体流量为500 mL/min,H2体积分数为15%,水浴温度为313 K)。当脱碳温度为1 413 K时,Ar-H2-H2O气氛下,脱碳时间为50 min时,脱碳后的平均碳质量分数为0.6%,Ar-CO-CO2气氛下,脱碳时间为70 min时,脱碳后的平均碳质量分数为0.92%。当脱碳时间相同时,Ar-H2-H2O的脱碳效果优于Ar-CO-CO2的脱碳效果,由于随着脱碳反应的进行薄带表面与氧化气体反应达到平衡,Ar-H2-H2O反应平衡时薄带的碳活度要低于Ar-CO-CO2气氛条件的碳活度,导致Ar-H2-H2O气氛条件下薄带的碳浓度梯度高于Ar-CO-CO2气氛条件,进而导致Ar-H2-H2O气氛条件的扩散通量大,脱碳效果好。 相似文献
110.
采用超音速等离子喷涂技术在纯铜基体上制备Cr2O3-Ni-5%A(l质量分数)陶瓷涂层。利用XRD、SEM、激光共聚焦显微镜(LSCM)、显微硬度仪对涂层进行表征与分析,通过Image-pro Plus图形软件计算涂层的孔隙率,并通过摩擦磨损试验评价涂层的耐磨性能。结果表明:除了喷涂过程中出现了少量铬的氧化外,起始粉末和涂层的物相没有发生变化;陶瓷涂层表面呈双态组织,其表面粗糙度(Ra)为4.763μm;涂层断口形貌为典型的片层状组织,在涂层的抛光截面上可见紧密的富铬带均匀分布;Cr2O3涂层的孔隙率为1.2%,显微硬度为1 640HV0.3;涂层在室温下的摩擦因数约为0.4,其磨损机制为磨粒磨损。 相似文献