[Microbiological studies of spiced beef burgers in Tripoli city, Libyan Arab Jamahiriya]

We investigated the microbiological quality of uncooked and cooked spiced beef burger in restaurants and fast food places in Tripoli city and surrounding areas. Thus 151 samples [92 cooked and 59 uncooked] were analysed microbiologically. The results showed that all samples were highly contaminated with bacteria; 74.5%, 28.8%, 27.1% and 18.6% of the uncooked samples were contaminated with Escherichia coli, Aeromonas spp., Staphylococcus aureus and E. coli O157:H7 respectively. Additionally 11.9%, 9.9%, 5.4% and 3.2% of the cooked samples were contaminated with E. coli, Aeromonas spp., E. coli O157:H7 and S. aureus respectively

Effect of calcium and nucleotide on the degradation and water holding capacity of myofibrillar proteins.

Beef chicken myofibrollar proteins were used as substrates to study the effect of CaC1[2], ATP and beef musclc lysosomal enzymes on protein degradation. Degradation of beef and chicken myofibrillar proteins was measured using sodium dodecyl sulfate polyacrylamide gel electrophoresis [SDS-PAGE], water holding capacity [WHC] and non-protein nitrogen [NPN]. The reaction were carried out at pH 5.5 and 7.0 at 4° and 37° for 1.5,6,24 and 96 hr. The influence of CaC1[2], ATP and lysosomal enzymes independently and in combination on WHC of myofibrillar proteins was studied. CaC1[2] or ATP decreased WHC at both pH 5.5 and 7.0. The WHC of the treated sample with a mixture of CaCl[2] and ATP was less than that of untreated proteins. The WHC of samples reached with lysosomal enzymes was enhanced by adding ATP, CaC1[2], and a mixture of both