Penentuan Suhu dan Lama Penyimpanan Recovery Milk untuk Efisiensi Sistem Pendinginan Ice Water PT XYZ

Abstract

Recovery milk merupakan produk susu hasil pengalihan dari proses fill to drain dan divert to drain pada unit UHT yang masih memiliki nilai gizi dan dapat dimanfaatkan kembali setelah penyimpanan sementara. Namun, belum diketahui batas waktu dan suhu penyimpanan optimal yang mampu menjaga mutu serta efisiensi energi pendinginan. Penelitian ini bertujuan untuk menentukan suhu dan lama penyimpanan optimal recovery milk serta menganalisis pengaruhnya terhadap mutu fisik-kimia (pH, total solid, protein, dan lemak) dan mikrobiologi (TPC, spora mesofilik, spora termofilik, dan bakteri psikrotrofik), serta mengevaluasi konsumsi energi sistem pendinginan berbasis ice water. Penelitian menggunakan rancangan faktorial dua faktor, yaitu suhu penyimpanan (5°C, 8°C, dan 10°C) dan lama penyimpanan (0, 24, 48, 72, dan 96 jam). Data dianalisis dengan ANOVA dan uji lanjut DMRT (a = 0,05), sedangkan konsumsi energi dihitung menggunakan neraca panas. Hasil menunjukkan bahwa penyimpanan pada suhu 10°C mampu mempertahankan mutu recovery milk selama 5 hari dengan penghematan energi sebesar 16% (energi yang digunakan sebesar 52 kWh) dibandingkan suhu 5°C. Penelitian ini menjadi dasar strategi efisiensi energi tanpa menurunkan mutu dan keamanan produk di PT XYZ.

Recovery milk is a milk product diverted from the fill-to-drain and divert-to-drain processes in a UHT unit that still has nutritional value and can be reused after temporary storage. However, the optimal storage time and temperature limits that can maintain quality and energy efficiency of cooling are unknown. This study aimed to determine the optimal temperature and storage duration of recovery milk, to analyze their effects on physical-chemical (pH, total solids, protein, and fat) and microbiological (TPC, mesophilic spore, thermophilic spore, and psychrotrophic bacteria), as well as to evaluate the energy consumption of an ice water-based cooling system. The study used a factorial design with two factor, namely storage temperature (5°C, 8°C, and 10°C) and storage duration (0, 24, 48, 72, and 96 hours). Data were analyzed using ANOVA and DMRT (a = 0.05), while energy consumption was calculated using a energy balance. The results showed that storage at 10°C was able to maintain the quality of recovery milk for 5 days with energy savings of 16% (energy used was 52 kWh) compared to a temperature of 5°C. This research serves as the basis for an energy efficiency strategy without reducing product quality and safety at PT XYZ.