DETERMINATION OF OPTIMUM PH AND TEMPERATURE FOR PASTEURIZATION OF CITRUS JUICES BY RESPONSE-SURFACE METHODOLOGY

1993-01-01
Ülgen, Neşe
Özilgen, Mustafa
Optimization of microbial death, enzyme inactivation and vitamin C retention during pasteurization of pH-adjusted orange juice is discussed free of equipment-dependent parameters such as the heating lag. The pH-temperature optimum was determined by response surface methodology in the range of 65-degrees-C-75-degrees-C and pH 2.5 4.0. The results implied that there was no pectin-esterase activity below pH 3.5. Leuconostoc mesenteroides had its maximum and minimum thermal resistance at pH 3.5 and pH 2.7, respectively. For an ideal theoretical process requiring four log cycles of microbial reduction the optimum pasteurization conditions were 12 min at 75-degrees-C and pH 2.7.
ZEITSCHRIFT FUR LEBENSMITTEL-UNTERSUCHUNG UND-FORSCHUNG

Suggestions

Efficiency of pulse pressure treatment for inactivation of Escherichia coli and Listeria innocua in whole milk
BUZRUL, Sencer; Alpas, Hami; LARGETEAU, Alain; DEMAZEAU, Gerard (Springer Science and Business Media LLC, 2009-05-01)
Escherichia coli ATCC 11775 and Listeria innocua ATCC 33090 in whole milk were inactivated by single- and multi-pulsed (up to 10 pulses) high hydrostatic pressure (HHP) treatments. Both bacteria showed similar resistance to single- and multi-pulsed HHP. The efficiency of pulsed pressure treatment depends on the combination of holding time of each pulse and number of pulses. It was observed that multi-pulsed pressure treatment instead of traditional single-pulsed HHP could be used to pasteurize milk at a low...
Functional properties of microwave-treated wheat gluten
Yalcin, Erkan; Sakiyan, Ozge; Şümnü, Servet Gülüm; Celik, Sueda; KÖKSEL, HAMİT (Springer Science and Business Media LLC, 2008-09-01)
In this study, the effects of microwave treatments on solubility, foaming and emulsifying properties of gluten were investigated. The solubility of microwave-heated gluten proteins gradually decreased as the treatment time increased, at all power levels applied. The highest solubility values were obtained for gluten samples microwave treated at 50% power level. The lowest emulsifying capacity values were obtained with the samples heated at 100% power level at all treatment times. The emulsifying stability v...
Studies on an inhibitor produced by lactic acid bacteria of wines on the control of malolactic fermentation
Yurdugul, S; Bozoglu, F (Springer Science and Business Media LLC, 2002-07-01)
Malolactic fermentation is the microbiological process in wines, where lactic acid bacteria (LAB) govern the process of converting L-malic acid into L-lactic acid. During this process a high microbial load of LAB may lead to an unwanted spoilage phenomena by formation of excessive amounts of undesirable flavor compounds. This study is mainly focused on the isolation of LAB from the native flora of the wine, which has an inhibitory potential against malolactic activity of LAB inherent in wines. An isolate of...
Optimization of microwave frying of osmotically dehydrated potato slices by using response surface methodology
Öztop, Halil Mecit; Şahin, Serpil; Şümnü, Servet Gülüm (Springer Science and Business Media LLC, 2007-04-01)
Microwave frying of osmotically dehydrated potatoes was optimized by using response surface methodology. Osmotic dehydration was applied prior to microwave frying in order to reduce oil uptake and to evaluate the effect of osmotic dehydration on quality of microwave fried potatoes. Moisture content, oil content, hardness and color of the fried potatoes were used as quality parameters. Microwave power level (400, 550, 700 W), frying time (1.5, 2.0, 2.5 min) and osmotic dehydration time (15, 30, 45 min) were ...
Modeling high pressure inactivation of Escherichia coli and Listeria innocua in whole milk
Buzrul, Sencer; Alpas, Hami; Largeteau, Alain; DEMAZEAU, Gerard (Springer Science and Business Media LLC, 2008-06-01)
The survival curves of Escherichia coli and Listeria innocua inactivated by high hydrostatic pressure (HHP) were obtained at room temperature (similar to 22 degrees C) and at five pressure levels (400, 450, 500, 550 and 600 MPa) in whole milk. These curves were described by the Weibull model and parameters of this model were reduced from two to one with slight loss of goodness-of-fit. The logarithm of the time constant parameter (delta) of the reduced Weibull model was described with respect to high pressur...
Citation Formats
N. Ülgen and M. Özilgen, “DETERMINATION OF OPTIMUM PH AND TEMPERATURE FOR PASTEURIZATION OF CITRUS JUICES BY RESPONSE-SURFACE METHODOLOGY,” ZEITSCHRIFT FUR LEBENSMITTEL-UNTERSUCHUNG UND-FORSCHUNG, pp. 45–48, 1993, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/64615.