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Wang X.,China Agricultural University | Xiao X.,China Agricultural University | Zhu Z.,National Engineering Technology Research Center for Preservation of Agricultural Products | Zhang Y.,China Agricultural University | And 2 more authors.
Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery | Year: 2016

Modified atmosphere techniques and preservation technologies, coupling with cold-chain have been approved themselves as key tools to prevent spoilage and prolong shelflife for the fruit storage and transportation. Taking table grape as example, modified atmosphere techniques create gaseous microenvironments which usually consist of reduced O2, elevated CO2 concentrations compared to air and fresh keeping agent of sulfur dioxide which commonly used to release SO2 and strongly retard the growth of these pathogenic fungis. Thus, there is an increasing concern about gas monitoring to improve the transparency and traceability during cold-chain. However, the existed industrial gas sensor can not meet the demand of cold-chain logistics in scale and precision. Then, the paper aimed to extract the static and dynamic response characteristics of gas sensors for table grape cold-chain logistics, which developed the method of characteristic parameter extraction based on time domain, and the carbon dioxide, oxygen and sulfur dioxide were developed as basic parameters. The method of linear regression was used to optimize characteristics of gas sensors, so the best feature parameters were got for gas sensing signal, which contain the response of gas sensor in the air, steady response of gas sensor, the speed of response and response recovery, time of response and response recovery, and response integrated signal respectively. The best feature parameters can be used to analyze the characteristics of gas sensing signal which has a cumulative effect on the quality in cold-chain. It is possible to improve the application and monitoring precision, monitoring sensitivity and monitoring stability of gas sensor in the cold-chain logistics further more. © 2016, Chinese Society of Agricultural Machinery. All right reserved.


Chen X.,China Agricultural University | Mu W.,China Agricultural University | Peter S.,University of Trnava | Zhang X.,China Agricultural University | Zhu Z.,National Engineering Technology Research Center for Preservation of Agricultural Products
Journal of Food and Nutrition Research | Year: 2016

In this work, 10 treatments of Kyoho grapes were preserved to analyse the effects of constant concentrations of sulfur dioxide (SO2) and temperature on the quality evolution of table grapes to provide references for the preservation technology improvement and the shelf life prediction. With the increase in SO2 concentration and the decrease in temperature, the peak time of soluble solids content was delayed or the rising stage disappeared. The addition of SO2 elevated the apparent activation energy of brown stain, which made the rate of the increase in brown stain more sensitive to temperature. The addition of SO2 showed an effect of inhibition and delay, together with low temperature, on the accumulation of saccharides in table grapes in the early storage. The change in pH value in an environmental range, which is a common situation in actual cold-chain logistics, showed a trend of monotone decrease and could be described by using a unified model. The evolution of pH value and brown stain could be used as reference indices for the shelf life prediction of table grapes in corresponding surroundings. © 2016 National Agricultural and Food Centre (Slovakia).


Chen X.,China Agricultural University | Zhu Z.,National Engineering Technology Research Center for Preservation of Agricultural Products | Zhang X.,China Agricultural University | Mu W.,China Agricultural University | Fu Z.,China Agricultural University
Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery | Year: 2015

As an important research direction of food sector, shelf life prediction has become a hot topic worldwide. The related research literatures were summarized, the research mechanism and research progress of food shelf life prediction were reviewed, and the related research ideas and research methods were clarified. Five types of research methods were analyzed and compared, including the method based on chemical kinetics, the method based on growth kinetics of microbial, the method of back propagation (BP) neural networks, the method of Weibull hazard analysis and the method based on temperature such as Q10 model. Quality indexes and research models used in different kinds of foods' shelf life prediction, such as meat, aquatic product, fruits and vegetables, which were proved to be available to achieve good results, were summarized. Finally, the status of food shelf life prediction research was analyzed and its development tendency was presented in the respects of research mechanism, study object and its surroundings, research applications and dynamic monitoring. Analysis indicates that food shelf life prediction tends to be more accurate and utility. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.


Huang Y.-F.,Nankai University | Huang Y.-F.,National Engineering Technology Research Center for Preservation of Agricultural Products | Li Y.,Nankai University | Jiang Y.,Nankai University | Yan X.-P.,Nankai University
Journal of Analytical Atomic Spectrometry | Year: 2010

The use of magnetic microspheres and nanoparticles for sample extraction in analytical chemistry has received increasing interest. However, previous magnetic particle-based solid-phase extraction (SPE) is usually performed in a batch mode. In this work, we report magnetic immobilization of amine-functionalized magnetite (Fe3O4) microspheres (AF-MMPs) onto the inner walls of a knotted reactor (KR) for on-line SPE coupled with ICP-MS for speciation analysis of trace chromium. A tubular magnet is sufficient to immobilize AF-MMPs onto the inner walls of a KR without the need for any frits or plugs. Sensitive speciation analysis of trace CrIII and CrVI in water was achieved based on selective on-line SPE of either CrIII and CrVI under controlled pH conditions on an AF-MMPs magnetically immobilized KR integrated into a flow injection system with on-line ICP-MS detection without the need for extra oxidation/reduction. On-line SPE of 2.4 mL aqueous solution gave an enhancement factor of 96 for CrIII and 47 for CrVI, a detection limit of 1.5 ng L -1 for CrIII and 2.1 ng L-1 for CrVI at a sample throughput of 23 h-1. The precision (RSD) for eleven replicate measurements of 100 ng L-1 CrIII and Cr VI was 1.9% and 4.5%, respectively. The batch-to-batch reproducibility (RSD) for three parallel prepared AF-MMPs packed KRs for the SPE of CrIII and CrVI at 100 ng L-1 was less than 5.5%. One AF-MMPs packed KRs can be used for at least 75 cycles of preconcentration without significant loss of extraction efficiency. The developed method was successfully applied to the speciation analysis of trace CrIII and CrVI in drinking water samples. © 2010 The Royal Society of Chemistry.


Kou X.,Tianjin University | Liu X.,Tianjin University | Li J.,National Engineering Technology Research Center for Preservation of Agricultural Products | Xiao H.,Tianjin University | Wang J.,Tianjin University
Journal of the Science of Food and Agriculture | Year: 2012

Background: Aroma is one important fruit sensory attribute influenced by the volatile constituents related to species, variety and technological treatments. We analysed the variations of volatile compounds in five pear cultivars and investigated their changes related to different pear organs, different ripening stages, 1-MCP treatment and ultra-high-pressure pasteurisation. Results: Considerable variations exist in the quantity of 10 volatile compounds among five pear cultivars. Their levels generally showed an increasing trend when collected at later harvest time in Ya pear. In Whangkeumbae pear, most volatile compounds reached their maximum levels in skin and pulp. After treating pears with 42 μmol L -1 1-methylcyclopropene (1-MCP), the levels of volatiles remained basically unchanged or only slightly increased in Ya pear during a shelf life of 21 days. When Huangguan pear juice was pasteurised by using ultra-high pressure, the levels of volatiles significantly changed during the shelf life. Conclusion: The volatile compositions of five different Chinese pear cultivars differ considerably. The levels of these volatiles vary along with ripening stages and pear tissues. A moderate concentration of 1-MCP could keep the levels of volatile compounds basically unchanged during storage and ultra-high-pressure pasteurisation could change the levels of volatiles significantly during the following shelf life. © 2011 Society of Chemical Industry.


Zhang P.,ShenYang Agricultural University | Li J.,National Engineering Technology Research Center for Preservation of Agricultural Products | Meng X.,ShenYang Agricultural University | Zhang P.,National Engineering Technology Research Center for Preservation of Agricultural Products
Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery | Year: 2011

In order to seek an effective deastringency and crispness-keeping technique for astringent persimmons, the effects of different 1-MCP concentration, polyvinylhloride(PVC) and vacuum packaging methods on physiology and storage of Mopan persimmons under ambient temperature were investigated. Results showed that 1-MCP combined with individual vacuum packaging effectively inhibited the decline of fruit firmness, the increase of ethylene production and respiration intensity, malondialdehyde (MDA) content and peel tissue relative conductance, prevented the evaporation of fruit moisture during storage, promoted the change of the soluble tannin content to insoluble tannin content and prolonged ambient shelf life time to 14d. Therefore, 0.5 to 1.0 μL/L 1-MCP of combined with individual vacuum packaging was a suitable treatment method for Mopan persimmons.


Huang Y.-F.,Nankai University | Huang Y.-F.,National Engineering Technology Research Center for Preservation of Agricultural Products | Wang Y.-F.,Tianjin University of Science and Technology | Yan X.-P.,Nankai University
Environmental Science and Technology | Year: 2010

Interest in magnetic nanoparticles for capturing bacteria arises from a variety of attributes, including the similar size of nanoparticles, magnetic behavior, and attached biomolecules such as proteins and nucleotide probes. Here we report the application of amine-functionalized magnetic nanoparticles (AF-MNPs) for rapid and efficient capture and removal of bacterial pathogens. The AF-MNPs are used without the need for any further modifications with affinity biomolecules. The positive charges on the surface of AF-MNPs can promote strong electrostatic interaction with negatively charged sites on the surface of bacterial pathogens to exhibit efficient adsorptive ability. The hydrophobic interaction between the pendant propyl group of the amine functionality and the bacteria also plays a supplementary role. The amine groups on the surface of the magnetic nanoparticle are robust and inexpensive ligands to ensure a high binding affinity to at least eight different species of Gram-positive and Gram-negative bacteria. The amount of AF-MNPs, pH of phosphate buffer solution, and ionic strength are crucial in mediating fast and effective interactions between AF-MNPs and bacteria. The AF-MNPs allow rapid removal of bacteria from water samples, food matrixes, and a urine sample with efficiency from 88.5% to 99.1%. Though amino group offers less specificity/selectivity than biomolecules such as antibodies, AF-MNPs are attractive for capturing a wide range of bacteria. © 2010 American Chemical Society.


Liu B.,Tianjin University of Commerce | Zhu L.,Tianjin University of Commerce | Ye Q.,Tianjin University of Commerce | Yuan R.,National Engineering Technology Research Center for Preservation of Agricultural Products
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2012

The compensated water in the vacuum cooling is helpful to reduce the water loss of the cooled products. The effects of packed rate and the compensated water before cooling on storage period of King oyster mushroom were investigated by experiments. The packed rate was 20%, 40% and 60% respectively. The compensated water was 0, 12 and 18 g/kg respectively. The initial temperature was 11°C and 16°C respectively. The results show that the pressure of boiling point will increase with the increasing of the packed rate, and precooling time of mushroom in the vacuum slot will prolong. The compensated water has little influence on the pressure of vacuum cooling, but has influences on water loss and precooling time of mushroom in the vacuum cooling process. After 14 days storage at 0°C, the mushrooms can keep good quality under the condition of 18 g/kg compensated water and 20% packed rate.


Ma H.,Northwest Agriculture and Forestry University | Song S.,Northwest Agriculture and Forestry University | Ma Y.,Northwest Agriculture and Forestry University | Liu F.,Northwest Agriculture and Forestry University | And 2 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2012

In order to provide basis of a new simple effective technology for green walnut fruit storage, the effect of modified atmosphere package on refrigerated storage of the fruit was investigated. Green walnut fruit of variety Liaoning No.4 were stored under 0~1°C with different packages of plastic film, i.e. improved polyvinyl chloride (mPVC), modified polyethylene (thn-PE, thk-PE) and complex treatment of 1-MCP fumigation plus mPVC to test the effect of modified atmosphere (MA) packages on gas concentrations in each bag, postharvest physiology as well as storability of the fruit. Results showed that among all packages tested thk-PE bags showed strongest MA-effect, which adjusted inner-bag O 2 and CO 2 volume fraction during storage to 10.1%~13.0%, 4.3%~6.5%, respectively. Both the respiration intensity and ethereal production rate of green walnut fruit showed two-peak type trend during the storage. MA package delayed appearance of each peak and significantly (p < 0.01) decreased peak values. Soluble solids content of fruit from both treatment and control all increased during early storage phase and then decreased, but the decrease from each treatment occurred earlier than that from control. MA package significantly (p < 0.01) reduced fruit weight loss and thk-PE bag had the best effect. MA packages also reduced the decay rate of fruit. Rotting index of fruit in thk-PE bag was 30.0% after 66 days storage and 68.6% after 95 days, which were significant (p < 0.01) lower than that in other packages. Therefore, thk-PE bag can be selected as the suitable MA approach for the storage of green walnut fruit, which can keep 100% preservation rate of walnut after a storage period of about 95 days.


Jiang Z.-T.,Tianjin University of Commerce | Wang Y.,Tianjin University of Commerce | Chen S.-H.,Tianjin University of Commerce | Guan W.-Q.,National Engineering Technology Research Center for Preservation of Agricultural Products
Journal of Essential Oil-Bearing Plants | Year: 2011

Volatile oil of Origanum majorana L. grown in China was separated by using hydrodistillation (HD). The chemical components of the oil were identified by GC-MS technique and comparison of retention indices with those of C8-C40 standard alkanes. Forty components were characterized, representing 94.5 % of total volatile oil. Major components are terpinen-4-ol (33.0 %), caryophyllene oxide (11.9 %), p-cymene (6.8 %), α-terpineol (6.7 %) and spathulenol (6.0 %). © 2011, Har Krishan Bhalla & Sons.

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