The Effect of Audiosonic Waves on Microbial Activities in Yoghurt Fermentation

Yoghurt is well known dairy product that is able to help digestion process. Its value can be increased using several innovation method, such as probiotic bacteria addition and unique physical treatment. This study found that the highest glucose level observed in yoghurt without any audiosonic exposure treatment was at 0.1656%, with the addition of 2000 Hz frequency was at 0.2128%, and with the addition of 8000 Hz frequency was at 0.114%. The highest protein content in yoghurt without any audio sonic treatment was found at 0.418%, with the addition of Zymomonas mobilis bacteria and 2000 Hz frequency was at 0.333%, and with the addition of Streptomyces sp. and 8000 Hz frequency was 0.328%. The highest fat content in yoghurt with Zymomonas mobilis bacteria was 18.29%, with 2000 Hz audiosonic treatment was at 10.58%, and with 8000 Hz frequency was at 9.333%. Based on the research, it can be concluded that the nutritional value of yoghurt with Zymomonas mobilis bacteria and Streptomyces sp. can be increased with audisonic exposure treatment.