Abstract:
Milk can be used as a processed food, one of which is yogurt-curd. Curd has a quality that depends
on the amount of Lactic Acid Bacteria (LAB), but the quality of the curd needs to be considered to
increase the shelf life of the long curd because many rogue producers add harmful substances to the
curd. Degradation (damage) that occurs in the curd in this study can be identified using an impedance
electronic circuit with an excitation voltage source from the Multi I/O Card PCI 6221 National
Instruments based on LabVIEW software which will measure the impedance, imaginary, and phase
angle values of the curd quality. The curd impedance measurement process is carried out by injecting
AC current using platinum electrodes, where the frequency parameters ranging from 10 Hz to 50 kHz
are varied using LabVIEW software. In addition, organoleptic tests were also carried out on the curd,
namely, taste, aroma, texture and color. Measurement of curd quality degradation was carried out for
5 days and the impedance value increased with time.
