Use of Weibull frequency distribution model to describe the inactivation of Alicyclobacillus acidoterrestris by high pressure at different temperatures

Alpas, Hami
Bozoglu, F
The survival curves of Alicyclobacillus acidoterrestris by high hydrostatic pressure were obtained at two pressures (350 and 450 MPa) and three temperature levels (35, 45 and 50 degreesC) in BAM broth. Tailing (upward concavity) was observed in all survival curves. Weibull model was fitted to these data and goodness of fit of this model was investigated. Regression coefficients (R-2), root mean square (RMSE) values and residual plot strongly suggested that Weibull model produced good fit to the data. A better fit was observed for the data at lower pressure (350 MPa). Shape factors of the Weibull model (n values) for 350 NMPa at 35, 45 and 50 degreesC were significantly different from each other (P < 0.05). Two linear emprical equations were obtained for scale factors (b values) at the temperature values studied for 350 and 450 MPa. Such pressure-temperature inactivation models form the engineering basis for design, evaluation and optimization of high hydrostatic pressure processes as a new preservation technique.


Thermal and chemical inactivation of lactococcal bacteriophages
BUZRUL, Sencer; OZTURK, Pinar; Alpas, Hami; AKÇELİK, Mustafa (Elsevier BV, 2007-01-01)
Ten lactococcal bacteriophages in M 17 broth were treated by heat (72 degrees C, 15 min and 90 degrees C, 5 min), ethanol and isopropanol at concentrations of 10%, 50%. 75% and 100% (v/v). The heat treatments were not sufficient to inactivate all the bacteriophages studied whereas ethanol, which was also more efficient biocide than isopropanol, at a concentration of 75% could inactivate all the phages in I min. The 50% and 75% of ethanol were more effective than 100%, which was also observed for isopropanol...
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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...
Recovery of strawberry aroma compounds by pervaporation
Isci, A; Şahin, Serpil; Şümnü, Servet Gülüm (Elsevier BV, 2006-07-01)
The main objective of this study was to determine the effects of feed temperature (30, 40, 50 degrees C), concentration (50, 100, 150 ppm), composition (different strawberry model solutions) and permeate pressure (4, 8 mbar) on recovery of strawberry aroma compounds by pervaporation. Pervaporation was performed using a hydrophobic membrane, PERVAP 1070 (PDMS). As the feed temperature increased or downstream pressure decreased, the mass flux and selectivity increased in pervaporation of methyl butyrate (MTB)...
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BUYUKCAN, Mehmet; BOZOGLU, Faruk; Alpas, Hami (Wiley, 2009-08-01)
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Dik, Tunay; Özilgen, Mustafa (Elsevier BV, 1996-11)
Rheological behaviour of bentonite – apple juice suspensions were experimentally determined at 25°C, within the shear rate range of 4.3 to 43.1 s−1with 0.90, 1.33 and 2.66 g/L bentonite mixtures and 0 to 0.25 g/L (on dry basis) gelatin concentrations. The mixtures consisted of 100%, 80%, 60%, 40% 20% and 0% Ca-bentonite and balance Na-bentonite combinations. The experimental data were described with the power law as τ =Kγ.1.56. The consistency index was related to the calcium, sodium and gelatin concentrati...
Citation Formats
S. BUZRUL, H. Alpas, and F. Bozoglu, “Use of Weibull frequency distribution model to describe the inactivation of Alicyclobacillus acidoterrestris by high pressure at different temperatures,” FOOD RESEARCH INTERNATIONAL, pp. 151–157, 2005, Accessed: 00, 2020. [Online]. Available: