The effectiveness of exposure to magnetic fields of extremely low frequency 300T and 500T in inhibiting the proliferation of pathogenic bacteria to increase physical resistance of vannamei shrimp

Abstract

Vannamei shrimp is a type of fish that rots easily, only able to survive about 6 hours at room temperature. This study aims to examine the effectiveness of exposure to an Extremely Low Frequency (ELF) magnetic field with an intensity of 300 T and 500 T in inhibiting the proliferation of pathogenic bacteria to increase the physical resistance of white vaname shrimp. The research design used a completely randomized design and was carried out at the Physics Laboratory of the Faculty of Teacher Training and Education, University of Jember. The Extremely Low Frequency (ELF) magnetic field in this study is a component of the ELF electromagnetic wave generated by the Current Transformer by minimizing the exposure to the ELF electric field to about 30 V/m. The study sample was 210 fresh vaname shrimp and divided into 7 treatment groups, namely the control group (K), the group exposed to the ELF magnetic field intensity of 300 T for 60 minutes (E-300.60’), 90 minutes (E-300.90’), 120 minutes (E-300.120’), and the group exposed to an ELF magnetic field of 500 T intensity for 60 minutes (E-500.60’), 90 minutes (E-500.90’), 120 minutes (E-500,120’). As an indicator of vaname shrimp resistance at room temperature is the population of pathogenic bacteria, color, aroma, texture, mucus, and pH. The research data were analyzed using One Way Anova analysis. The results showed that the population of Salmonella bacteria was significantly lower than the control in the vannamei shrimp sample exposed to an ELF magnetic field of 500 T, but the population of E.Coli bacteria increased significantly in the vannamei shrimp sample exposed to an ELF magnetic field of 300 T and 500 T compared to control. Naturally, vaname shrimp stored at room temperature showed the appearance of the shrimp getting paler, and the texture getting softer, smelling rotten and slimy after the 6th hour. However, the color, smell, and texture of shrimp exposed to an ELF magnetic field of 500 T intensity for 120 minutes were able to survive at a score of 8 at the 5th hour observation and 7th at the 10th hour observation. Conclusion: Exposure to an ELF magnetic field with an intensity of 500 T was effective in suppressing the proliferation of salmonella Sp bacteria but was less effective in suppressing the proliferation of E.Coli bacteria. This condition affects the physical condition of white shrimp until it lasts at the 10th hour. The results of this study serve as the basis for developing food security technology by the ELF magnetic field.