The objective of this study was to investigate the survival of coliphage MS2 as a surrogate for enteric viruses under different process conditions in the production of traditional ice cream. The results showed that heat treatment (73 8C, 10 min) decreased the recovery of coliphage MS2 to 1.33, 1.11, and 0.97 log10 (pfu/ml) in nonfrozen ice cream samples with 15%, 10%, and 5% fat, respectively. Also the homogenization process (22,000 rpm in 1 min) decreased the recovery of coliphage MS2 in nonfrozen ice cream samples with 15%, 10%, and 5% fat, to 2.33, 2.20, and 2.10 log10 (pfu/ml), respectively. All data in frozen ice cream samples was less than that of nonfrozen. Pasteurization along with homogenization decreased the recovery of MS2 coliphage to 0.85 and 0.66 (pfu/ml) in nonfrozen and frozen ice cream samples, respectively. However, these processes cannot totally eliminate all of the MS2 coliphages. During the storage time (6 weeks), ice cream samples showed the lowest recovery of coliphage MS2 in the sixth week, and highest recovery of coliphage MS2 on the first day. It was then concluded that pasteurization along with homogenization has the most marked effect on the elimination of coliphage MS2 in frozen ice cream.

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