The potential translocation of E. coli
O157:H7 from the surface to the interior of
whole muscle by blade tenderization was evaluated.
Beef top sirloin subprimals were inoculated
with 106 or 103 cfu/cm2 and passed once
through a Ross blade tenderization unit. Core
samples showed a translocation of 3 to 4% of
surface inoculum to the geometric center of the
subprimal. A second study evaluated thermal
destruction of E. coli O157:H7 in blade tenderized
(BT) steaks compared to nontenderized
(NT) steaks of three thicknesses when ovenbroiled.
Subprimal surfaces were inoculated to
a level of 107 cfu/cm2 and blade tenderized.
Steaks cut from these subprimals were ovenbroiled
to internal temperatures from 120 to
170°F, then analyzed for surviving E. coli
O157:H7. At internal steak temperatures of
140°F and higher, all E. coli O157:H7 were
killed in both BT and NT steaks of all thicknesses.
At 130°F, about 5 log reductions were
noted for both BT and NT. With oven broiling
to even moderate internal temperatures, BT
steaks pose no greater risk of E. coli O157:H7
infection than NT steaks.
