EFFECT OF MICROWAVE AND SOME TREATMENTS ON MICROBIAL INACTIVATION RATE OF MILK | ||
| Misr Journal of Agricultural Engineering | ||
| Article 20, Volume 27, Issue 2, April 2010, Pages 737-745 PDF (418.69 K) | ||
| Document Type: Original Article | ||
| DOI: 10.21608/mjae.2010.105941 | ||
| Authors | ||
| T.H. Ghanem1; M.A.M Omar2 | ||
| 1Associate Prof., Agric. Eng.. Fac. of Agric., Al-Azhar Univ. (Cairo), Egypt. | ||
| 2Associate Prof., Dairy Science Dept. Faculty of Agric.,Al-Azhar Univ.(Cairo), Egypt. | ||
| Abstract | ||
| The aim of the present work is to study the effect of three different microwave power levels of 285, 385 and 470 W and alternating mixed treatments (20 seconds in microwave and 20 seconds sudden cooling) repeated one, two and three times on the total microbial counts (CFU/g) of milk . It was found that as the microwave power increases the total microbial counts decreases from 3.6x1010 to 2.4x104 CFU/g. Insignificant differences were found between 385 and 470 W for the pure microwave treatments. The decimal reduction time were 10.36 s, 7.87 and 7.49 s for the three power levels respectively. For the mixed alternating treatments the power level of 470 gives the least total bacterial count of 3.3x103 CFU/g compared to 3.5x103 for the power level of 385W at 2450 MHz. The decimal reduction times were 39.23 and 38.90 s for 385 and 470 W for the three times treatments respectively. Semi-logarithmic models were satisfied for the pure microwave and alternating mixed treatments with coefficient of determination of 0.98. | ||
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