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Nonaqueous Phase (nonaqueou + phase)
Selected AbstractsINVOLVEMENT OF PEROXIDASE AND POLYPHENOL OXIDASE IN MANGO SAP-INJURYJOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2002K. SABY JOHN ABSTRACT Sap (latex) that oozes out from mango during harvest, upon contact with the fruit, causes dark spots (sap-injury) on the peel and reduces consumer acceptance and shelf-life of fruit. In this investigation different components responsible for sap-injury were identified. Mango saps from four Indian varieties were collected and separated into aqueous and nonaqueous phases. Whole sap, aqueous phase and nonaqueous phase were tested for their ability to cause sap-injury (browning) on mangoes. The nonaqueous phase caused maximum injury and the extent of injury caused by nonaqueous phases from different varieties was varied. Limonene, ocimene and ,-myrcene, the major terpenoids identified in saps of Indian varieties, caused injury. Similar type of injury on mangoes was also caused by organic solvents. Damage on Totapuri mango fruit was significantly lower compared to other varieties, whereas Totapuri nonaqueous phase caused injury on all other varieties. The peel of Totapuri variety had very low level of polyphenol oxidase, peroxidase and polyphenols compared to other varieties. Thus, a clear relation was found between the peel polyphenol oxidase, peroxidase activities, the polyphenol content in the peel and the extent of injury. Further, nonaqueous phase applied on peels previously heat-treated at 95C for 5 min, neither caused injury nor showed any enzyme activity. Thus, the results indicated that the terpenoid components of sap and polyphenol oxidase, peroxidase, polyphenols of peel are involved in sap-injury. [source] Cubic-plus-association equation of state for water-containing mixtures: Is "cross association" necessary?AICHE JOURNAL, Issue 7 2009Zhidong Li Abstract We have recently proposed an accurate version of the cubic-plus-association (CPA) equation of state (EOS) for water-containing mixtures which combines the Peng-Robinson equation (PR) for the physical interactions and the thermodynamic perturbation theory for the hydrogen bonding of water molecules. Despite the significant improvement, the water composition in the nonaqueous phase is systematically underestimated for some systems where the nonwater species are methane and ethane at very high pressures, unsaturated hydrocarbons, CO2, and H2S. We attribute the deficiency to the neglect of the "cross association" between water and those nonwater molecules. In this work, the accuracy is drastically improved by treating methane, ethane, unsaturated hydrocarbons, CO2 and H2S as "pseudo-associating" components and describing the cross association with water in the framework of the perturbation theory. It is shown that the cross association is more significant for the nonaqueous phase. In addition to binary mixtures, reliable predictions are achieved for H2O/C1/CO2/H2S quaternary mixture in two and three phases. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] INVOLVEMENT OF PEROXIDASE AND POLYPHENOL OXIDASE IN MANGO SAP-INJURYJOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2002K. SABY JOHN ABSTRACT Sap (latex) that oozes out from mango during harvest, upon contact with the fruit, causes dark spots (sap-injury) on the peel and reduces consumer acceptance and shelf-life of fruit. In this investigation different components responsible for sap-injury were identified. Mango saps from four Indian varieties were collected and separated into aqueous and nonaqueous phases. Whole sap, aqueous phase and nonaqueous phase were tested for their ability to cause sap-injury (browning) on mangoes. The nonaqueous phase caused maximum injury and the extent of injury caused by nonaqueous phases from different varieties was varied. Limonene, ocimene and ,-myrcene, the major terpenoids identified in saps of Indian varieties, caused injury. Similar type of injury on mangoes was also caused by organic solvents. Damage on Totapuri mango fruit was significantly lower compared to other varieties, whereas Totapuri nonaqueous phase caused injury on all other varieties. The peel of Totapuri variety had very low level of polyphenol oxidase, peroxidase and polyphenols compared to other varieties. Thus, a clear relation was found between the peel polyphenol oxidase, peroxidase activities, the polyphenol content in the peel and the extent of injury. Further, nonaqueous phase applied on peels previously heat-treated at 95C for 5 min, neither caused injury nor showed any enzyme activity. Thus, the results indicated that the terpenoid components of sap and polyphenol oxidase, peroxidase, polyphenols of peel are involved in sap-injury. [source] | ||||||||||