Changes in quality of pineapple juice concentrate during heating and storage : kinetics and prediction | |
| Author | Ting, Cesar Chow |
| Call Number | AIT Thesis no. AE-89-18 |
| Subject(s) | Fruit juices, Concentrated Food--Storage |
| Note | A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | Quality changes of food materials during heat processing and storage with interpretation by kinetics were studied. Steady state and unsteady state heating were considered for non-enzymatic browning and ascorbic acid degradation . Accelerated storage test was done , for analysis of non-enzymatic browning, color change and ascorbic ac id degradation. Quality study was done for pineapple juice concentrate with important consideration on color change or browning development . Determination of kinetic parameters by steady state method was done u sing thermal death time tubes (TDT) and come up time tubes (CUT) . Effect of factors 0 Brix , ascorbic acid , pH, a nd container material on color stability was e valuated , during storage. Kinetic parameter d e termination by unsteady method involved the development of a computer program for predicting the temperature distribution in the can. Th e temperature distribution was determined by a modified numerical finite difference method solution. Quality retention program during unsteady state h eating process was developed based on kinetics and temperature distribution. The standard reaction rate k and activation energy Ea, for browning and ascorbic acid were determined by steady state procedure. For color change , standard reaction rate k a nd activation energy Ea, were obtained by minimization of residuals. It was concluded that for h eating study, kinetic reaction rate at 97°C and activation energy was 0 . 0112 min- 1 and 62.88 KJ/mole, respectively; 0 . 0158 min- 1 a nd 64.359 KJ/mole for non -enzymatic browning a nd ascorbic acid degradation. During storage kinetic reaction rate at 30° C and activation energy were 0 .1197 min- 1 and 32.64 KJ/mole, respectively ; 0 . 00018 min- 1 a nd 34.8 7 KJ/mole for non-enzymatic browning and color change. |
| Year | 1989 |
| Type | Thesis |
| School | School of Environment, Resources, and Development |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Athapol Noomhorm; |
| Examination Committee(s) | Illangantileke, Sarath G. ;Tran, Francis T. ;Panda, T. ; |
| Scholarship Donor(s) | Government of Australia ; |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 1989 |