No abstract

Cured and uncured turkey rolls inoculted with 10' List&u monocytogenes CFU/g were vacuum packaged and cooked to internal temperatures of 68°C and 74"C, respectively, in a steam-injected chamber. Samples were stored up to 15 wk at 4°C. Battered chicken nuggets were also inoculated internally with about 1O'L. monocyfogenes CFU/ g. Nuggets enclosed in bags were cooked under moist heating conditions in a convection oven to an internal temperature of 71°C. Nuggets were flushed with 30% COZ, 70% NZ atmosphere and sealed. Chicken nuggets were stored at 4°C up to 30 days. No Listeria monocytogenes were recovered from the cooked products suggesting that similar commercial processes are adequate to reduce populations of L. monocyfogenes below detection limits.

This report terminates a 3-year study and includes data from this past year. Previous results were reported in the 1976 and '77 Cattlemen's Day Report.

Thirty-eight crossbred steers of known background were randomly assigned to four feeding regimes. All initially were fed on a brome and bluestem pasture supplemented during winter with alfalfa and protein. Ten grass-fed animals were slaughtered directly off pasture at the end of summer. Ten steers were fed an additional 49 days (short-fed), and eight 98 days (long-fed) on 80 percent concentrate and 20 percent corn silage. In addition, ten silage-fed animals were fed 60 percent corn silage and 40 percent concentrate for 98 days. Carcass characteristics were evaluated along with shear force (tenderness) and taste panel responses.

We used 150 Angus yearling steers of similar background from the Livestock and Meat Industry Council cattle-flow project. Each was assigned to one of the 12 treatments (10 per treatment) involving low-, medium-, and high-energy rations (calculation to supply 34, 45, and 58 megacalories per 100 lbs. ration for net energy of production). Times on rations were 56, 91, 119, 147, and 175 days. Ten steers were fed a submaintenance ration of prairie hay 28 days before slaughter, and 10 served as controls (slaughtered when study started).

Ten steers of known background, approximately 18 months old, and wintered on alfalfa and protein were finished on a brome and bluestem grazing program. Carcass characteristics were measured. The influence of conditioning carcass halves at 55 F until eight hours post-mortem was compared with conventional chilling at 36 F. Finally, the effects of vacuum storage and display on beef quality were evaluated.