Thermal processing of milk is an important unit operation to inactivate the spoilage organism and enzymes and thus increase the storage life of milk, It was very difficult to find out the temperature distribution insi...Thermal processing of milk is an important unit operation to inactivate the spoilage organism and enzymes and thus increase the storage life of milk, It was very difficult to find out the temperature distribution inside the cans during thermal processing. A Computational Fluid Dynamics (CFD) model was developed for thermization of milk in the can heating at 65℃ for the first time to determine the temperature distribution in the canned milk at stationary position. This developed CFD model was validated with the experimental measurements of temperature. The effects of thermization temperature on milk flow profile (velocity), milk temperature and viscosity profiles inside the can during thermal process were investigated. Temperature profiles of milk in can at three different planes (i.e. top, middle and bottom plane) were studied. Moreover, thermization unit was calculated by correlating with temperature and it was found that maximum thermization unit was achieved at 540 s of thermal processing of milk in can.展开更多
Neera is the sweet juice or sap, obtained by tapping the unopened inflorescence of the coconut palm and is rich in minerals. In order to improve the nutritional quality and acceptability of the product a trial was car...Neera is the sweet juice or sap, obtained by tapping the unopened inflorescence of the coconut palm and is rich in minerals. In order to improve the nutritional quality and acceptability of the product a trial was carried out to combine aloe cubes and strawberry flavour with neera. Aloe vera is a flavourless and translucent white soft gel with bland taste and rich in phytonutrients and electrolytes. Standard neera (SN) was prepared with neera alone (100%) and compared against experimental neera (EN) prepared with neera (87%), aloe vera cubes (10%) and strawberry extract (3%). The processed neera was packed in presterilized bottles and stored at 5 ℃. Organoleptic acceptability and storage stability study were carried out every week. Physicochemical characteristics and selected nutrient content were analysed on 0th day and at the end of storage period. Overall acceptability of EN (8.5 ± 0.53) was higher than SN (8 ± 0.82) on 0th day and over different storage periods. There was a gradual decrease in the organoleptic scores of both EN and SN on storage and it was unacceptable on 56th day of storage. The sodium, potassium and vitamin C content of EN were significantly higher than SN. The TSS of SN and EN were 14 ± 0°B/100 mL and 15.6 ± 0 °B/100 mL respectively on 0th day. Significant (p ≤0.01) increase in the microbial count in EN was noticed on storage.展开更多
At the molecular mechanic level, the capability of a set of 24 molecular cage-like structures, the spherophanes, to store hydrogen molecules has been studied. Two main factors have been found to govern their storage c...At the molecular mechanic level, the capability of a set of 24 molecular cage-like structures, the spherophanes, to store hydrogen molecules has been studied. Two main factors have been found to govern their storage capacity: the volume of their cavity and the potential energy barriers at the different openings at the surface of the cage. Calculations have shown that 13H2 molecules could be stored inside the thiaspherophane, Th4S, whose mean radius is 10A and the resulting complex (H2)I3@Th4S is found to be stable. The results show that it would be very difficult to store more than 2H2 inside the smallest spherophane, Sp4, whose mean radius is 7.7A. The mean intermolecular distance Hz-Hz and the mean bond length H-H have been found to decrease when the number of imprisoned hydrogen molecules increases. It has also been found that the encapsulated H2 molecules form clusters of different symmetries on which the formation energy depends strongly. Even with 13H2 molecules inside Th4S, the weight percentage is still small, 2.57%. The largest obtained wt% is 3.22% in the case of Th5S(CH3)10.展开更多
文摘Thermal processing of milk is an important unit operation to inactivate the spoilage organism and enzymes and thus increase the storage life of milk, It was very difficult to find out the temperature distribution inside the cans during thermal processing. A Computational Fluid Dynamics (CFD) model was developed for thermization of milk in the can heating at 65℃ for the first time to determine the temperature distribution in the canned milk at stationary position. This developed CFD model was validated with the experimental measurements of temperature. The effects of thermization temperature on milk flow profile (velocity), milk temperature and viscosity profiles inside the can during thermal process were investigated. Temperature profiles of milk in can at three different planes (i.e. top, middle and bottom plane) were studied. Moreover, thermization unit was calculated by correlating with temperature and it was found that maximum thermization unit was achieved at 540 s of thermal processing of milk in can.
文摘Neera is the sweet juice or sap, obtained by tapping the unopened inflorescence of the coconut palm and is rich in minerals. In order to improve the nutritional quality and acceptability of the product a trial was carried out to combine aloe cubes and strawberry flavour with neera. Aloe vera is a flavourless and translucent white soft gel with bland taste and rich in phytonutrients and electrolytes. Standard neera (SN) was prepared with neera alone (100%) and compared against experimental neera (EN) prepared with neera (87%), aloe vera cubes (10%) and strawberry extract (3%). The processed neera was packed in presterilized bottles and stored at 5 ℃. Organoleptic acceptability and storage stability study were carried out every week. Physicochemical characteristics and selected nutrient content were analysed on 0th day and at the end of storage period. Overall acceptability of EN (8.5 ± 0.53) was higher than SN (8 ± 0.82) on 0th day and over different storage periods. There was a gradual decrease in the organoleptic scores of both EN and SN on storage and it was unacceptable on 56th day of storage. The sodium, potassium and vitamin C content of EN were significantly higher than SN. The TSS of SN and EN were 14 ± 0°B/100 mL and 15.6 ± 0 °B/100 mL respectively on 0th day. Significant (p ≤0.01) increase in the microbial count in EN was noticed on storage.
文摘At the molecular mechanic level, the capability of a set of 24 molecular cage-like structures, the spherophanes, to store hydrogen molecules has been studied. Two main factors have been found to govern their storage capacity: the volume of their cavity and the potential energy barriers at the different openings at the surface of the cage. Calculations have shown that 13H2 molecules could be stored inside the thiaspherophane, Th4S, whose mean radius is 10A and the resulting complex (H2)I3@Th4S is found to be stable. The results show that it would be very difficult to store more than 2H2 inside the smallest spherophane, Sp4, whose mean radius is 7.7A. The mean intermolecular distance Hz-Hz and the mean bond length H-H have been found to decrease when the number of imprisoned hydrogen molecules increases. It has also been found that the encapsulated H2 molecules form clusters of different symmetries on which the formation energy depends strongly. Even with 13H2 molecules inside Th4S, the weight percentage is still small, 2.57%. The largest obtained wt% is 3.22% in the case of Th5S(CH3)10.