Analisis Dinamika Populasi Bakteri dan Fisikokimia Susu UHT Selama Penyimpanan pada Suhu Refrigerator

Abstract

Susu merupakan produk pangan yang banyak dijumpai dan disajikan dalam berbagai varian produk dengan komposisi dan ukuran kemasan yang berbeda. Penyimpanan dalam suhu refrigerator biasa dilakukan dalam menyimpan produk susu. Populasi bakteri serta fisikokimia diyakini berubah selama periode penyimpanan meskipun dinamika perubahan populasi bakteri masih kurang dipelajari. Penelitian ini bertujuan mengetahui perubahan populasi bakteri dan fisikokimia susu UHT komersial pada varian produk full cream dan low fat dengan merek produk yang sama selama penyimpanan pada suhu refrigerator. Produk susu UHT komersial yang digunakan berasal dari merek Greenfields yang disimpan dalam refrigerator selama 15 hari serta diamati perkembangan populasi bakteri dan perubahan fisikokimia. Percobaan dilakukan dengan rancangan acak lengkap dan lama penyimpanan (0, 7, dan 15 hari). Hasil penelitian menunjukkan bahwa susu UHT tidak memiliki perbedaan yang signifikan selama penyimpanan. Susu dengan penyimpanan 7 hari sudah tidak baik lagi untuk dikonsumsi, meskipun pH dan kandungan nutrisinya masih cukup baik dikarenakan oleh berkembangnya bakteri terutama bakteri E. coli yang jumlahnya telah melebihi SNI.

Milk is a food product that is often found and is presented in various product variants with different compositions and packaging sizes. Storage in the refrigerator temperature is usually done in storing dairy products. The bacterial population as well as physicochemistry is believed to change during the storage period although the dynamics of bacterial population change are still poorly studied. This study aims to determine the changes in bacterial population and physicochemistry of commercial UHT milk in full cream and low fat product variants with the same product brand during storage at refrigerator temperature. The commercial UHT milk products used were from the Greenfields brand which was stored in the refrigerator for 15 days and observed bacterial population development and physicochemical changes. The experiment was conducted in a completely randomized design and storage time (0, 7, and 15 days). The results showed that UHT milk did not have a significant difference during storage. Milk with 7 days of storage is no longer good for consumption, even though the pH and nutritional content are still quite good due to the development of bacteria, especially E. coli bacteria whose number has exceeded SNI.