Enumeration of Psychrotrophic Bacteria in Raw Milk Inoculated with Lactic Acid Bacteria by the Agar Droplet Method.

Selected cultures of lactic acid bacteria (LAB) can be added to raw milk with the aim of inhibiting growth of pyschrotrophic bacteria. We compared the standard pour plate method (7°C/10 d) and a rapid surface plate method (18°C/45 h) with the agar droplet method for enumeration of psychrotrophs in raw milks seeded with LAB. The LAB did not interfere with the standard method or the 7°C/5 d agar droplet method, but interfered with the surface plate method.

Comparison of the amino acid composition of the intracellular and extracellular matrix protein fractions isolated from avian skeletal muscles.

Intracellular and extracellular skeletal muscle protein fractions were isolated from the legs and breasts of young and adult White Leghorn chickens and quantified by detailed amino acid analysis. This involved repeated homogenization in the presence of 50 mM CaCl2, neutral phosphate-buffered saline (pH 7.4), solubilization by 2% sodium dodecyl sulfate (SDS), and centrifugation to separate all intracellular muscle proteins from the extracellular matrix.