ASSAY AND STORAGE-CONDITIONS AFFECT YIELD OF SALT SOLUBLE-PROTEIN FROM MUSCLE

Pork and beef muscles were used to evaluate assay and storage conditio n effects on yields of salt soluble protein (SSP). Assay conditions in cluded pH (5.5, 6.0 or 6.5), extraction volume (6, 9, 12 or 15 X sampl e weight), homogenization time (30, 60, 90 or 120 sec) and centrifugal force (2500, 4000 or 5500 x g). Storage conditions included postmorte m aging (4-degrees-C for 0, 7 or 14 days) and freezing conditions (rap id freezing, slow freezing, and freezing-thawing-freezing). Highest yi eld of SSP was obtained using pH 6.0, extraction volume 15 X sample we ight, centrifugation at 4000 x g and homogenization time 90 to 120 sec for both pork- and beef. Freezing conditions did not affect measureme nt of SSP. Aging beef for 7 and 14 days post-mortem reduced the yield of SSP; however, such differences were not observed for pork.