Physical and Sensory Characteristics of Synbiotic Yogurt with the Addition of Pomegranate Peel (Punica granatum L.) Extract

¹ Animal Science Study Program, Faculty of Agriculture, Universitas Sumatera Utara, Prof. A. Sofyan Street No.3, Medan, 20155, Indonesia
² Bachelor Program of Animal Science, Faculty of Agriculture, Universitas Sumatera Utara, Prof. A. Sofyan Street No.3, Medan, 20155, Indonesia
³ Animal Science Study Program, Faculty of Agriculture, Universitas Tanjungpura, Prof. Hadari Nawawi Street, Pontianak, 78121, Indonesia
⁴ Animal Science Study Program, Faculty of Agriculture, Universitas Tidar, Barito 1, Kedungsari, Magelang, 56116, Indonesia

^* Corresponding author: windafransisca@usu.ac.id

Abstract

Pomegranate peels are agricultural waste that still contains bioactive compounds, such as polyphenols and polysaccharides, which act as natural antioxidants and prebiotics. Polysaccharides exert prebiotic effects by promoting the growth and activity of beneficial lactic acid bacteria. In this study, we aimed to develop a new yogurt product by utilizing pomegranate peel (Punica granatum L.) extract. The yogurt was made using skim milk powder and the lactic acid bacteria strains Lactobacillus bulgaricus and Streptococcus thermophilus as the main ingredients. The synbiotic yogurt was made using different concentrations of pomegranate peel extract at T0 (control), T1 (0.5%), T2 (1%), and T3 (1.5%). Physical characteristic tests include the pH, syneresis, and water holding capacity. Sensory analysis was conducted on 30 panelists using a 5-point Likert scale with test parameters including aroma, taste, color, and overall acceptability. The results revealed significant differences (p<0.05) in the pH, syneresis, and sensory aroma values of synbiotic yogurt. The addition of pomegranate peel extract to yogurt resulted in an average pH between 4.07 – 4.30, syneresis between 34.80 – 44.38% and aroma value of 3.77 – 4.12. In terms of sensory quality, yogurt with the addition of pomegranate peel extract was almost identical to the control, except for T2 due to its strong sour aroma. In conclusion, synbiotic yogurt with 0.5% pomegranate peel extract was the best of all the treatments. Thus, the pomegranate peel extract formulated into yoghurt can be considered as a functional ingredient to improve yogurt’s physical and sensory characteristics.