VALIDATION OF THE EFFECT OF INTERVENTIONS AND PROCESSES ON PERSISTENCE OF PATHOGENS ON FOODS
Location: Food Safety and Intervention Technologies
Title: Evaluation of high pressure processing, freezing, and fermentation/drying on viability of Trichinella spiralis larvae in raw pork and in Genoa salami
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: July 15, 2009
Publication Date: July 20, 2009
Citation: Call, J.,Porto-Fett,A.,Shoyer,B.,Pshebniski,C.,Cocoma,G.,Hill,D.,Luchansky,J. 2009. Evaluation of high pressure processing, freezing and fermentation/dryaing on viability of Trichinella spiralis larvae in raw pork and in Genoa salami [abstract].IAFP Annual Meeting.Grapevine,TX.p.1.
We evaluated high pressure processing (HPP), freezing, and fermentation/drying to inactivate Trichinella spiralis larvae in both infected pig muscle and in Genoa salami produced with trichinae infected pork. In part A, in each of two trials 10 gram portions (2 replicates per treatment) of fresh pig massetter muscle (ca. 3.6 log10 larvae/g) were pressurized with either 70,000 or 87,000 psi (483 or 600 mPa, respectively) for 0.5 to 5.0 min or 10 gram portions (2 trials, 2 replicates per trial) of fresh pork (ca. 3.2 log10 larvae/g) harvested from trichina infected swine were frozen at -20 degrees C. Microscopic examination and a mouse bioassay showed that all combinations of pressure and time, as well as exposure to -20 degrees C for 30 days, completely inactivated the larvae. In part B, Genoa salami prepared with trichinae infected pork (ca. 2.3 larvae/g of salami batter) was fermented at 20 degrees C for 6 hours and then at 27 degrees C for 26 hours before being dried at 20 degrees C for 40 hours and then at 17 degrees C as follows: i) for 25 days (65 mm casing; aw 0.881 + 0.012) or 35 days (105 mm casing; aw 0.918 + 0.007), or ii) to a target aw of 0.920 that was attained between 11 to 18 days (65 mm casing; aw 0.920 + 0.006) or iii) to a target aw of 0.940 that was attained between 19 to 24 days (105 mm casing; aw 0.939 + 0.004). After drying, four chubs in each of three trials for each treatment were post-processed pressurized at 70,000 or 87,000 psi for 0 to 12 min. T. spiralis was inactivated in Genoa salami by all treatments of fermentation/drying and/or HPP as confirmed by both microscopy and mouse bioassays. These findings validate that HPP of raw pork, as well as fermentation/drying or HPP of Genoa salami, are as effective as freezing at -20 degrees C for 30 days for inactivating T. spiralis larvae.