PENGARUH PAPARAN MEDAN MAGNET EXTREMELY LOW FREQUENCY (ELF) TERHADAP pH ROTI TAWAR

ABSTRAKRoti tawar adalah sumber karbohidrat memiliki umur simpan yang sangat pendek yakni empat sampai enam hari terhitung dari proses masa produksi. Penelitian ini bertujuan menyelidiki pengaruh paparan medan magnet Extremely Low Frequency (ELF) intensitas 500 µT dan 700 µT selama 60, 90, dan 120 menit terhadap pH roti tawar. Jenis penelitian yang digunakan yaitu eksperimen dengan desain penelitian Rancang Acak Lengkap (RAL). Ada dua kelompok dalam penelitian ini, yakni kelompok kontrol dan kelompok eksperimen dimana kelompok kontrol yang tidak dipapari medan magnet dan kelompok eksperimen diberi paparan medan magnet. Sampel yang digunakan dalam penelitian ini adalah roti tawar sari roti kupas sebanyak 126 sisir dimana kelompok kontrol sebanyak 18 sisir roti tawar dan kelompok eskperimen sebanyak 108 sisir roti tawar yang dibagi menjadi enam kelompok yang diberi perlakukan berupa paparan medan magnet ELF dengan intensitas 500 µT dan 700 µT selama 60, 90 dan 120 menit. Teknik analisis data dilakukan menggunakan SPSS 22 dengan uji Kruskal-Wallis. Berdasarkan hasil penelitian yang diperoleh paparan medan magnet ELF berpengaruh terhadap perubahan pH pada roti tawar. Dengan memaparkan medan magnet intensitas 500 µT lama paparan 60 menit dan 700 µT lama paparan 60 menit dapat menghambat penurunan pH roti tawar. Kata kunci: Medan Magnet ELF; Roti Tawar; pH. ABSTRACTBread is a source of carbohydrates that has a very short shelf life of four to six days from the production process. This study aims to examine the effect of exposure to an Extremely Low Frequency (ELF) magnetic field with an intensity of 500 µT and 700 µT for 60, 90, and 120 minutes on the pH of white bread. This research uses an experimental research type with the research design used is Completely Randomized Design (CRD). There were two groups in this study, namely the control group and the experimental group where the control group was not exposed to a magnetic field and the experimental group was exposed to a magnetic field. The samples used in this study were 126 combs of peeled white bread, where the control group consisted of 18 white bread combs and the experimental group consisted of 108 white bread combs which were divided into six groups which were treated in the form of exposure to the ELF magnetic field with an intensity of 500 µT and 700 µT for 60, 90 and 120 minutes. The data analysis technique was carried out using SPSS 22 with the Kruskal-Wallis test. The results of the study stated that exposure to the ELF magnetic field had an effect on changes in pH in white bread as shown by a graphic diagram. Exposure to a magnetic field intensity of 500 µT with an exposure time of 60 minutes and 700 µT with an exposure duration of 60 minutes can inhibit the decrease in the pH of white bread. Keywords: Magnetic Field; White Bread; pH.

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Pengaruh Paparan Medan Magnet Extremely Low Frequency (ELF) terhadap Perubahan pH Pada Proses Fermentasi Biji Kopi Lanang (Peaberry) Kering

Jurnal Kumparan Fisika ◽

10.33369/jkf.4.2.129-136 ◽

2021 ◽

Vol 4 (2) ◽

pp. 129-136

Author(s):

Mamik Purbawati ◽

Sudarti Sudarti ◽

Firdha Kusuma A A

Keyword(s):

Magnetic Field ◽

Fermentation Process ◽

Low Frequency ◽

Control Group ◽

Extremely Low Frequency ◽

Coffee Beans ◽

Post Test ◽

Frequency Magnetic Field ◽

Group Variation ◽

Elf Magnetic Field

ABSTRAK Kopi lanang (Peaberry) merupakan jenis kopi yang mempunyai biji berkeping satu (monokotil) dengan kafein yang kadarnya lebih tinggi jika dibandingkan dengan kopi jenis lain. Kadar kafein yang tinggi pada biji kopi bisa diturunkan dengan proses fermentasi kopi. Penelitian ini mempunyai tujuan untuk mengetahui pengaruh paparan medan magnet ELF (Extremely Low Frequency) terhadap perubahan pH pada proses fermentasi biji kopi lanang (Peaberry) kering jenis robusta dengan penambahan enzim -amilase. Jenis penelitian yang digunakan yaitu penelitian eksperimen dengan desain Rancangan Acak Lengkap (RAL) bertujuan mengkaji pengaruh perlakuan dengan pengulangan percobaan. Penelitian ini memiliki tujuh kelompok sampel meliputi kelompok kontrol dan kelompok eksperimen variasi intensitas paparan medan manet ELF sebesar 200 µT dan 300 µT dan variasi lama pemaparan 30 menit, 60 menit dan 90 menit. Pengukuran data hasil penelitian diambil setelah pemaparan yaitu pada hari ke-1 sampai hari ke-5 selama proses fermentasi berlangsung. Hasil penelitian menyatakan bahwa paparan medan magnet ELF berpengaruh terhadap perubahan pH pada proses fermentasi biji kopi lanang (Peaberry) kering jenis robusta yang ditunjukkan dengan variasi bentuk grafik. Pemaparan medan magnet ELF dengan intensitas 200 µT dan lama pemaparan 30 menit dapat menurunkan pH secara signifikan, sedangkan intensitas 200 µT dan lama waktu paparan 90 menit dapat menaikkan pH secara signifikan pada proses fermentasi biji kopi lanang (Peaberry) kering jenis robusta. Kata kunci : Medan magnet ELF, Fermentasi, Kopi Lanang (Peaberry), pH ABSTRACT Peaberry coffee is a type of coffee that has a single bean (monocotyle) with a higher levels of caffeine if compared whith other types of coffee. High levels of caffeine in coffee beans can be reduced by the coffee fermentation process. The study aims to examine the effect of exposure to the ELF (Extremely Low Frequency) magnetic field on changes of pH in the fermentation process of robusta peaberry dray coffee beans with the addition of -amylase enzyme. The type of research that use in the experimental reseacrh with a randomized subject post test only control grup design, it aiming to examine the effect of treatment by repeating the experiment. This study include seven sample groups covering the control group and the experimental group variation in the intensity of ELF magnetic field with 200 µT and 300 µT and variation of a length 30, 60, 90 minutes. Meansurement of the data research taken after exposure that is on the day one to day five during the fermentation process. The result of the study suggest that exposure to ELF magnetic field has an effect on the pH fermentation prosess of dried peaberry coffee beans, which was shown variations of the shape of the graph. Exposure to the ELF magnetic field with an intensity of 200 µT and the length of 30 minutes can significantly decrease the pH, while the intensity of 200 µT and the length of 30 minutes can significantly increase the pH in the fermentation process of dried robusta paberry coffee beans. Keywords : ELF magnetic field, Fermentation, Peaberry Coffee, pH

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Effect of 50 Hz magnetic field on chicken embryo development and course of hatching

Science Technology and Innovation ◽

10.5604/01.3001.0013.2877 ◽

2019 ◽

Vol 5 (2) ◽

pp. 44-49

Author(s):

Marcin Lis

Keyword(s):

Magnetic Field ◽

Chick Embryo ◽

Chicken Embryo ◽

Low Frequency ◽

Quality Analysis ◽

Control Group ◽

Control Groups ◽

Extremely Low Frequency ◽

Helmholtz Coils ◽

Elf Magnetic Field

The effect of additional extremely low frequency (ELF) magnetic field (50 Hz) on the development of chick embryo was investigated. The experiment was carried out in three variants for induction values 15 μT, 10 μT and 5 μT. Magnetic field (MF) in the experimental incubator was generated by a set of three Helmholtz coils. The following analyses were performed: embryopathological analysis; evaluation of the hatched chicks for quality; analysis of the course and synchronization of hatching. Increased embryo mortality was found between 1 and 6 days of incubation in 15 μT MF and between 18 and 20 days of incubation in 5 μT MF. In each group exposed to MF, the principal stage of hatching was completed earlier. Increased degree of chick hatching synchronization was observed in MF of 5 μT and 10 μT. Hatching results in the control group were higher than in MF exposed groups. Statistically significant (p≤0.05) differences were found for chick malpositions in the groups incubated with exposure to additional MF of 10 μT and 5 μT compared to the control groups.

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PENGARUH PAPARAN MEDAN MAGNET EXTREMELY LOW FREQUENCY (ELF) TERHADAP pH DAN DAYA HANTAR LISTRIK PADA PROSES FERMENTASI BASAH KOPI LIBERIKA (Coffea liberica) DENGAN PENAMBAHAN α-AMILASE

ORBITA Jurnal Kajian Inovasi dan Aplikasi Pendidikan Fisika ◽

10.31764/orbita.v6i2.3294 ◽

2020 ◽

Vol 6 (2) ◽

pp. 315

Author(s):

Nanda Rizky Fitrian Kanza ◽

Sudarti Sudarti ◽

Maryani Maryani

Keyword(s):

Magnetic Field ◽

Electrical Conductivity ◽

Fermentation Process ◽

Low Frequency ◽

Control Group ◽

Control Group Design ◽

Extremely Low Frequency ◽

Post Test ◽

Wet Fermentation ◽

Elf Magnetic Field

ABSTRAKPenelitian ini bertujuan untuk mengkaji pengaruh paparan medan magnet Extremely Low Frequency (ELF) terhadap pH dan daya hantar listrik pada proses fermentasi basah kopi liberika dengan penambahan α-amilase. Jenis penelitian ini merupakan penelitian eksperimen dengan randomized subjects post test only control group design. Pada penelitian ini terdapat 7 perlakuan yang terdiri dari kelompok kontrol dan kelompok eksprimen yang dipapar medan magnet ELF dengan variasi intensitas 300 µT dan 400 µT dan variasi lama paparan 30 menit, 60 menit, dan 90 menit. Pengambilan data dilakukan pada jam ke-24, jam ke-48, hari ke-3, hari ke-4, dan hari ke-5 setelah proses fermentasi. Hasil penelitian menunjukkan bahwa paparan medan magnet Extremely Low Frequency (ELF) berpengaruh terhadap pH dan daya hantar listrik pada proses fermentasi basah kopi liberika dengan penambahan α-amilase yang ditunjukkan dengan bervariasinya grafik. Pengukuran kopi liberika dengan paparan medan magnet ELF intensitas 400 µT selama 30 menit paling berpengaruh terhadap pH kopi liberika. Sedangkan, pengukuran kopi liberika dengan paparan medan magnet ELF intensitas 300 µT selama 30 menit dan 90 menit paling berpengaruh terhadap daya hantar listrik kopi liberika yang telah difermentasi secara basah dengan penambahan α-amilase. Kata kunci: medan magnet ELF; pH; daya hantar listrik; fermentasi; kopi. ABSTRACTThe purpose of the research is to examine the effect of Extremely Low Frequency (ELF) magnetic field to pH and electrical conductivity in the wet fermentation process of liberica coffee with the addition of α-amylase. Type of the research is an experimental research with randomized subjects post test only control group design. There is seven treatments consist of control group and experimental group exposed to ELF magnetic field with 300 µT and 400 µT intensity variation and for 30, 60, and 90 minutes for long variations. For hours 24, 48, day 3, day 4, and day 5, can make data retrieval after fermentation process. The result explain is effect of Extremely Low Frequency (ELF) magnetic field to pH and electrical conductivity in the wet fermentation process of liberica coffee with the addition of α-amylase was take effect to indicated by the variation of the graph. The process ELF magnetic field with 400 µT intensity for 30 minutes most influential on pH of liberica coffee. Meanwhile, the process ELF magnetic field with 300 µT intensity for 30 and 90 minutes most influential on electrical conductivity of liberica coffee in the wet fermentation with the addition of α-amylase. Keywords: ELF magnetic field; pH; electrical conductivity; fermentation; coffee.

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Superconducting Extremely Low Frequency (ELF) Magnetic Field Sensors for Submarine Communications

IRE Transactions on Communications Systems ◽

10.1109/tcom.1974.1092212 ◽

1974 ◽

Vol 22 (4) ◽

pp. 549-554 ◽

Cited By ~ 17

Author(s):

S. Wolf ◽

J. Davis ◽

M. Nisenoff

Keyword(s):

Magnetic Field ◽

Low Frequency ◽

Magnetic Field Sensors ◽

Extremely Low Frequency ◽

Submarine Communications ◽

Elf Magnetic Field

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Optimizing lactobacillus growth in the fermentation process of artificial civet coffee using extremely- low frequency (ELF) magnetic field

Journal of Physics Conference Series ◽

10.1088/1742-6596/1465/1/012010 ◽

2020 ◽

Vol 1465 ◽

pp. 012010

Author(s):

Sudarti ◽

S Bektiarso ◽

S H B Prastowo ◽

T Prihandono ◽

Maryani ◽

...

Keyword(s):

Magnetic Field ◽

Fermentation Process ◽

Low Frequency ◽

Extremely Low Frequency ◽

Elf Magnetic Field

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Correlation between the Lunar Phase and Tail-Lifting Behavior of Lizards (Pogona vitticeps) Exposed to an Extremely Low-Frequency Electromagnetic Field

Animals ◽

10.3390/ani9050208 ◽

2019 ◽

Vol 9 (5) ◽

pp. 208 ◽

Cited By ~ 1

Author(s):

Tsutomu Nishimura ◽

Harue Tada ◽

Masanori Fukushima

Keyword(s):

Magnetic Field ◽

Full Moon ◽

Low Frequency ◽

Control Group ◽

Lunar Phase ◽

Extremely Low Frequency ◽

K Index ◽

Field Sensitivity ◽

Pogona Vitticeps ◽

New Moon

We previously showed that the agamid lizard Pogona vitticeps responded to an extremely low-frequency electromagnetic field (ELF-EMF; frequency: 6 and 8 Hz; peak magnetic field: 2.6 µT; peak electric field: 10 V/m) with tail-lifting behavior. In addition, the tail-lifting response to ELF-EMF disappeared when the parietal eyes of the lizards were covered by small round aluminum caps. This result suggests that the parietal eye contributes to light-dependent magnetoreception. In the present study, we set up an ELF-EMF group to evaluate the long-term effect of the ELF-EMF on lizards’ behavior and examine our hypothesis that exposure to ELF-EMFs increases the magnetic field sensitivity in lizards. We therefore include the lunar phase (full moon/new moon) and K index as environmental factors related to the geomagnetic field in the analysis. The number of tail lifts per individual per day was the response variable while calendar month, daily mean temperature, daily mean humidity, daily mean atmospheric pressure, full moon, new moon, and K index were the explanatory variables. We analyzed an ELF-EMF group and a control group separately. In a multiple linear regression analysis, the independent determinants associated with the number of tail lifts were the full moon, the temperature, February, March, April, and May in the ELF-EMF group and March, April, May, and June in the control group. The P. vitticeps in the ELF-EMF group responded to the full moon whereas those in the control group did not. In addition, in the ELF-EMF group, the number of tail lifts was higher on days when the K index was higher (P = 0.07) in the first period whereas there was no such tendency in either period in the control group. There is the possibility that the exposure to ELF-EMFs may increase magnetic-field sensitivity in lizards.

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