Variasi Suhu Dan Metode Pencampuran Terhadap Karakteristik Mutu Fisikokimia Dan TPC Susu Di PT XYZ

Abstract

Susu UHT adalah susu cair dari susu segar, rekonstitusi, atau rekombinasi yang disterilisasi pada suhu 135°C selama setara 3 menit. Di PT XYZ, ditemukan permasalahan mutu seperti susu pecah dan rasa asam yang diduga berasal dari ketidaksempurnaan proses pencampuran. Penelitian ini mengkaji pengaruh variasi suhu, yaitu 15°C dan 45°C, serta metode pencampuran langsung dan bertahap terhadap mutu susu, yang mencakup karakteristik fisikokimia (pH dan total padatan terlarut) serta mikrobiologis (total plate count/tpc). Penelitian dilakukan pada skala industri dan laboratorium menggunakan RAL dengan tiga perlakuan dan empat ulangan. Hasil penelitian menunjukkan bahwa suhu pencampuran berpengaruh signifikan terhadap pH dan TPC, namun tidak terhadap TPT. Perlakuan P3 (45°C, pencampuran langsung) menghasilkan pH 6,8, nilai TPT stabil yaitu (±10°Brix), dan TPC terendah sebesar 8,5 × 105 CFU/mL. Dengan demikian, kombinasi suhu 45°C dan metode pencampuran langsung direkomendasikan sebagai perlakuan optimal untuk menjaga mutu fisikokimia dan keamanan mikrobiologis susu UHT.

UHT milk is liquid milk derived from fresh, reconstituted, or recombined milk that is sterilized at 135°C for an equivalent of 3 minutes. At PT XYZ, quality issues such as milk curdling and sour taste were identified, which are suspected to result from improper mixing processes.This study examines the effect of temperature variation (15°C and 45°C) and mixing methods (direct and gradual) on milk quality, covering physicochemical characteristics (pH and total soluble solids) and microbiological aspects (total plate count/TPC).The research was conducted at industrial and laboratory scale using a Completely Randomized Design (CRD) with three treatments and four replications.Results showed that mixing temperature significantly affected pH and TPC, but not total soluble solids.Treatment P3 (45°C, direct mixing) yielded optimal results with pH 6.8, stable TSS (±10°Brix), and the lowest TPC of 8.5 × 105 CFU/mL.Therefore, the combination of 45°C temperature and direct mixing is recommended as the optimal treatment to maintain the physicochemical quality and microbiological safety of UHT milk.