Studies On The Characteristics Of Salted Egg In The Presence Of Garlic Oil

The salted egg is a diversified product that has longer storage period than fresh egg. Storage of eggs in a long period of time can cause a decline in egg quality. The physical, biological, and chemical damage will affect the nutrient changes in the egg. An effort to minimize egg damage is store the egg in a relatively long time by addition of subtances that serves as a barrier of damage. The use of spices such as garlic is predicted can inhibit the growth of bacteria in the salted egg. The literature indicated that the allicin compound in garlic inhibit the growth of bacteria. Some identified bacteria in the egg are Staphylococcus aureus, Escherichia coli, and Salmonella. These bacteria not only spoil the eggs, but also dangerous for human health because of their enteropathogenic effect. This study aims to examine the influences of garlic oil, salting and storage time in the microbial, chemical, and physical characteristics of salted egg. The benefit of this research was to provide information about the effect of garlic oil on antibacterial activity and the characteristics of salted egg.This research is conducted in several parts:at the first part on cultures of bacteria, determination of the antibacterial activity of garlic oil by MIC (Minimum Inhibitory Concentration) for both Gram positive and Gram negative bacteria in the egg, and inhibitory activity of garlic oil on nutrient broth. The second stage was making salted egg in the presence of garlic oil and subsequently evaluate the characteristics of microbiological, chemical (water content, total solids, pH of egg white, salt concentration, oil exudation by yolk, and sensory evaluation), and physical (egg white viscosity, yolk index, Haugh units, and texture profile analysis) of salted eggs every7days of salting time (28days). The third stage was evaluating characteristics of storage properties with two differents packaging method (vacuum and non vacuum) of salted egg in the presence of garlic oil and tested for total viable counts of bacteria, pH, TVB-N (Total Volatile Base Nitrogen) of salt eggs are performed during the storage time, every20days and are continued for at least180days for vacuum packaging method, every5days and are continued for at least20days for non vacuum packaging methods. And the fourth stage was evaluating physical characteristic of salted egg with different cooking methods and times (boiling with pressure for15;20;25minutes, boiling without pressure for15;20;25minutes and steaming for15;20;25minutes). The experimental design for in this study was completely randomized design with factorial factor for three replications (Gomez and Gomez,1995). For second stages was used completely randomized design with factorial factor A x B (3x5) with three replications. Factor A were supplementation of garlic oil with different concentration (0%;0.1%;0.5%) and factor B were different time for salting process (0;7;14;21;28days). For third stages which is storage properties with two differents packaging method (vacuum and non vacuum). Completely randomized design with factorial factor A x B (2x10) with three replications used for vacuum method. Factor A were supplementation of garlic oil with different concentration (0%;0.5%) and factor B were different time for storage process (0;20;40;60;80;100;120;140;160;180days). Completely randomized design with factorial factor A x B (2x5) with three replications used for non vacuum method. Factor A were supplementation of garlic oil with different concentration (0%;0.5%) and factor B were different time for storage process (0;5;10;15;20days). Tests for antibacterial activity were analyzed descriptively according to the mean of test results.The main results were as follows:antibacterial activity has been studied by incorporation of garlic oil as a natural antibacterial agent. The presence of0.2%v/v garlic oil in the nutrient broth decreased viable cell counts for Escherichia coli, Salmonella enteritidis, and Staphylococcus aureus. S. aureus growth was8.02log cycles decreases up to6.20log cycles after36h incubation. E. coli and S. enteritidis growth was8.44and8.10log cycles decreases up to6.40and6.39log cycles after24h incubation. MIC and MBC (Minimum Bactericidal Concentration) for this study were0.05%and0.1%v/v of garlic oil.Changes in chemical composition, physical and microbiology properties of duck egg were determined by supplementation of garlic oil and salting time. As the salting time increased, water content decreased and salt content increased (p<0.05). Viscosity and pH of egg white decreased with increasing salting time (p<0.05). Yolk index increased with increasing salting time (p<0.05). Oil exudation of cooked yolk increased as salting proceeded (p<0.05). As the salting times increased, decreased of the hardness, springiness, cohesiveness, gumminess, chewiness and resilience were generally found in cooked salted egg yolk (p<0.05). However, no differences in hardness, cohesiveness, gumminess, and chewiness were observed in supplementation0.5%v/v of garlic oil samples (p>0.05).Combine effects of garlic oil on salt egg and vacuum packaging methods on salted egg were determined and store at room temperature. Total Volatile Base Nitrogen (TVB- N) in egg white increased during storage time (p<0.05). The pH of egg yolk increased during storage time (p<0.05), and the pH of egg white with the supplementation0.5%v/v of garlic oil decreased during storage time (p<0.05) but for control samples no pH differences were found on egg white (p>0.05). No bacterial growth found on salt egg during storage time.Salted egg with different cooking methods and times showed that steam and boiling methods could be the best methods for cooking of salted eggs. Furthermore, these treatments improved the appearance and maintain the flavour of salted egg.