Karakteristik Yoghurt Spirulina Bubuk dengan Starter Lactobacillus plantarum SK (5) Selama Penyimpanan

Abstract

Pembuatan yoghurt spirulina bubuk dengan metode spray drying dapat dilakukan untuk meningkatkan masa simpan produk yoghurt spirulina. Tujuan penelitian ini membandingkan karakteristik yoghurt spirulina cair dan bubuk dan menentukan pengaruh penyimpanan terhadap nilai aw, viabilitas bakteri asam laktat, dan aktivitas antioksidan yoghurt spirulina bubuk selama 28 hari di suhu ruang. Yoghurt spirulina dibuat melalui fermentasi susu dengan 15% starter L. plantarum SK (5) dan 1.5% biomassa basah S. platensis hasil kultivasi. Yoghurt spirulina bubuk disimpan dalam kemasan PET/ALU/LLDPE pada suhu ruang (27-29 oC), lalu dilakukan pengamatan setiap 7 hari. Yoghurt spirulina bubuk memiliki kadar air, kadar protein, kadar lemak, nilai pH, kadar TAT, total BAL, dan aktivitas antioksidan yang berbeda nyata dengan yoghurt spirulina cair. Yoghurt spirulina bubuk memiliki rendemen 6.42%, nilai aw 0.32, kelarutan 72.75%, dan ukuran partikel 5.818 µm. Perlakuan lama penyimpanan tidak berpengaruh secara nyata terhadap total BAL yoghurt spirulina bubuk (P<0,05), namun nilai aw dan aktivitas antioksidan yoghurt spirulina bubuk mengalami perubahan yang signifikan setelah penyimpanan 28 hari.

Spirulina yoghurt shelf life could be improved by making a powdered yoghurt with spray drying method. The aim of this study was to compare the characteristics of liquid and powdered spirulina yoghurt and the changes in water activity (aw), lactic acid bacteria (LAB) viability, and antioxidant activity of powdered spirulina yoghurt during 28 days of storage. Spirulina yoghurt was made by fermentation process of milk with 15% starter of L. plantarum SK (5) dan 1.5% wet biomass of cultivated S. platensis. Spirulina yoghurt powder was kept in PET/ALU/LLDPE pouches at room temperature (27-29 oC), and observed per 7 days. The moisture content, protein content, fat content, pH values, TAT levels, total LAB, and antioxidant activity of spirulina yoghurt powder has a significant difference with spirulina liquid yoghurt. Spirulina yoghurt powder has 6.42% of yield, 0.32 of aw level, 72.75% of solubility, and 5.818 µm of particle size. The storage time treatment did not affect the total LAB of spirulina yoghurt powder significantly (P<0,05), but the aw levels and antioxidant activity was changed significantly after 28 days storage.