THE EFFECTS OF BEEF FAT REPLACEMENT WITH GEL AND MULTIPLE EMULSIONS FORMULATED WITH COMBINATION OF VEGETABLE OILS AND DIFFERENT ANTIOXIDANTS ON OXIDATION MECHANISMS OF SAUSAGE FORMULATION
Project no. 20131 · Status: Kapanmış · 2018
Summary
In this thesis, it was aimed to produce healthier beef sausages by using water-in-oil-in-water (W1/O/W2) double emulsion and oil-in-water (O/W) gelled emulsion as beef fat replacer and investigate the effects of replacement on quality and oxidative changes. This study is consisted of two main trials: In Trial I double emulsion was prepared with peanut oil (PO) and linseed oil (LO); In Trial II gelled emulsion was prepared with peanut oil and linseed oil was used as beef fat replacer in different ratios (50% and 100%) in beef sausages. PO and LO are susceptible to oxidative changes due to their rich content of unsaturated fatty acids. For this reason, ?-tocopherol, rosemary extract and ?-tocopherol-rosemary extract combination was used in emulsion formulation to inhibit oxidative changes. Within both trials, the characteristics of the emulsions were examined and the physical, chemical, technological, and sensory quality parameters of sausages were analyzed in both final products and during storage. In Trial I and Trial II, use of emulsions improved the technological characteristics of beef sausages and resulted higher emulsion stability than control samples. With respect to emulsion addition pH, L* and b* values increased while a* values decreased. Microstructure of samples were found smooth and homogenous due to emulsion addition. Use of PO and LO resulted sausages with higher MUFA and PUFA contents, and lowered the n6/n3 ratio as well as atherogenic and trombogenic indexes. Due to high amount of unsaturated fatty acids and effects during emulsion preparation, such as heat, mechanical effects and pressure, higher lipid oxidation results were found in products formulated with emulsions. However, use of antioxidants in emulsion formulation decreased oxidative changes; the best results were found in sausages with ?-tocopherol-rosemary extract in formulation. Purge loss was found higher in sausages formulated with only gelled or double emulsions. Generel acceptability of sausages formulated with double emulsion were found higher than control; however contradictory result was found in sausages formulated with gelled emulsion. As conclusion, use of different emulsions as beef fat replacer in beef sausages resulted sausages with higher technological characteristics and offered a potential to produce meat products with healthier fatty acid composition. Use of antioxidants can inhibit the oxidative changes due to unsaturated fatty acid content increment in sausage formulations.