Inovasi pengembangan pangan fungsional salah satunya dengan yoghurt susu kedelai (soyghurt) yang diperkaya bahan alami bernilai kesehatan. Stroberi
(Fragaria sp.) dipilih karena mengandung senyawa bioaktif antosianin dan fenolik. Formulasi ini memanfaatkan ekstrak daun
Stevia rebaudiana untuk menghasilkan rasa manis non-gula karena kandungan senyawa bioaktifnya juga bersifat antioksidatif. Penelitian ini mengevaluasi karakteristik mikrobiologis dan fisikokimia, menentukan aktivitas antimikroba dan antioksidan, serta mengetahui karakteristik sensori soyghurt dengan penambahan
pulp stroberi (10%, 15%, 20%, dan 30%) dan ekstrak daun stevia (0,5%). Penelitian menggunakan lima formulasi yaitu kontrol (Y1), 10% pulp stroberi + 0,5% stevia (Y2), 15% (Y3), 20% (Y4), dan 30% (Y5). Evaluasi mutu soyghurt meliputi Total Plate Count (TPC); Total Bakteri Asam Laktat (BAL); Angka Kapang Khamir (AKK); Total
Enterobacteriaceae; nilai pH; total asam laktat; kadar protein; uji aktivitas antimikroba terhadap
Escherichia coli, Staphylococcus aureus, dan
Candida albicans; uji antioksidan metode DPPH (presentase inhibisi); serta uji sensori oleh panelis tidak terlatih dengan analisis Friedman. Hasil penelitian menunjukkan bahwa nilai TPC soyghurt pada seluruh perlakuan (Y1–Y5) berada pada kisaran 2,65×10?–9,3×10? CFU/mL dan total BAL sebesar 1,85×10?–3,45×106 CFU/mL, sedangkan nilai AKK dan total
Enterobacteriaceae berada di bawah batas hitung (<2>E. coli dan
S. aureus diperoleh pada Y3 (1,60 ± 0,00 mm dan 1,20 ± 0,00 mm), sedangkan aktivitas antijamur tertinggi terhadap
C. albicans terdapat pada Y2 (9,10 ± 0,14 mm). Penambahan
pulp stroberi dan ekstrak daun stevia pada seluruh perlakuan cenderung menurunkan pH soyghurt dari 3,81 ± 0,05 menjadi 3,46 ± 0,01, meningkatkan total asam laktat dari 1,10 ± 0,03% menjadi 1,49 ± 0,09%, serta menurunkan kadar protein dari 5,51 ± 0,43% menjadi 4,37 ± 0,14%; namun tidak signifikan (p>0,05) pada ketiga parameter. Aktivitas antioksidan berdasarkan persentase DPPH Radical Scavenging Activity berbeda signifikan antar perlakuan (p<0>
One of the innovations in developing functional food is soy milk yogurt (soyghurt) enriched with natural ingredients with health value. Strawberries
(Fragaria sp.) were chosen because they contain bioactive anthocyanin and phenolic compounds. This formulation utilizes
Stevia rebaudiana leaf extract to produce a non-sugar sweet taste because the bioactive compounds also have antioxidative properties. This study evaluated the microbiological and physicochemical characteristics, determined the antimicrobial and antioxidant activities, and determined the sensory characteristics of soyghurt with the addition of strawberry pulp (10%, 15%, 20%, and 30%) and stevia leaf extract (0.5%). The study used five formulations, namely control (Y1), 10% strawberry pulp + 0.5% stevia (Y2), 15% (Y3), 20% (Y4), and 30% (Y5). Evaluation of soyghurt quality includes Total Plate Count (TPC); Total Lactic Acid Bacteria (LAB); Yeast Mold Number (YMN); Total
Enterobacteriaceae; pH value; total lactic acid; protein content; antimicrobial activity test against
Escherichia coli, Staphylococcus aureus, and
Candida albicans; antioxidant test using the DPPH method (inhibition percentage); and sensory testing by untrained panelists using Friedman analysis. The results showed that the TPC value of soyghurt in all treatments (Y1–Y5) was in the range of 2.65×10?–9.3×10? CFU/mL and total LAB was 1.85×10?–3.45×106 CFU/mL, while the YMN and total
Enterobacteriaceae values were below the counting limit (<2>E. coli and
S. aureus was obtained in Y3 (1.60 ± 0.00 mm and 1.20 ± 0.00 mm), while the highest antifungal activity against
C. albicans was found in Y2 (9.10 ± 0.14 mm). The addition of strawberry pulp and stevia leaf extract in all treatments tended to reduce the pH of soyghurt from 3.81 ± 0.05 to 3.46 ± 0.01, increase total lactic acid from 1.10 ± 0.03% to 1.49 ± 0.09%, and reduce protein content from 5.51 ± 0.43% to 4.37 ± 0.14%; but not significant (p>0.05) in all three parameters. Antioxidant activity based on the percentage of DPPH Radical Scavenging Activity differed significantly between treatments (p<0>
Kata Kunci : Soyghurt, Stroberi, Daun Stevia, Antimikroba, Antioksidan
