Viscosity of the Emulsion 13 Emulsion Stability 14 Muscle Proteins 20 Effect of Fat in Emulsions 30 Role of Water 33 The Role of Salts 35 Effect of pH 41 Effect of Temperature in Emulsification 42 Beneficial Effects of Air Reduction 43 EXPERIMENTAL 45 The Model System 45 The Sausage Emulsion 52 Experimental Design and Statistical Analysis 56 RESULTS AND DISCUSSION 58 The Model System 58

Meat emulsion formation under vacuum was studied in a model system and in a sausage emulsion. Sarcoplasmic and myofibrillar extracts from beef and pork infraspinatus muscle were used to compare emulsification of vegetable oil with or without vacuum. Vacuum treatment permitted more oil to be emulsified by all protein extracts. The proportional increase was greater for water-soluble than for salt-soluble extracts. Sausage emulsion was evaluated using frankfurters prepared in a vacuum chopper with or without vacuum. Product stability was improved by application of vacuum only for the entire chopping procedure. Cured color development was more rapid and more complete in the vacuum treatment. Without vacuum chopping, frankfurters showed more obvious cavitation and less density, confirming presence of air within the emulsion.