Effect of frequency and length of time of electrical pulses on cow milk treated with high-pulsed electric field and ultraviolet (UV) technology

¹ Food Engineering Technology Department, Politeknik Negeri Jember
² Food Technology Industry Department, Politeknik Negeri Jember
³ Agriculture Engineering Department, Politeknik Negeri Jember

Abstract

Milk is a nutrient-rich animal product but is prone to contamination by spoilage and pathogenic microbes due to its high protein content. Non-thermal sterilization using UV and high-pulsed electric fields (HPEF) offers a solution. This compact system includes a processing chamber with a stirrer, UV lamp, PEF electrodes, and control devices for efficient sterilization. The system operates without damaging the quality of the beverage, making it superior to conventional methods. This study aims to determine the appropriate frequency and length of time to be applied to cow’s milk. The research was conducted using a Factorial Randomized Block Design (FRBD) with two factors: frequency (10, 20, and 30 Hz) and duration (10, 15, and 20 minutes). The parameters tested in this study included total dissolved solids, solid non-fat, protein, fat, and total plate count (TPC). The results showed that increasing the frequency and duration effectively reduced the levels of total dissolved solids, TPC, and fat, while increasing protein and solid non-fat contents. Based on the analysis, HPEV-UV Milk contains TDS 7.30% - 7.80%, SNF 7.59% - 7.79%, protein 2.79% to 2.84%, fat 1.39% - 1.70%, and TPC 5.10 to 18.23 × 10⁶ CFU/g.