The assessment of the antioxidant and antibacterial activity of Mandarin peel powder and its impact on the symbiotic soft cheese quality

Abstract

Abstract Mandarin peel powder (MPP), which has a higher polyphenol concentration than edible parts, is the major source of bioactive ingredients. The total phenolic content (TPC), antioxidant content, and antibacterial activity of several mandarin peel extracts were evaluated. A starter containing Lactobacillus acidophilus LA5 and Streptococcus thermophilus as a mixed strain (1:1) with the addition of 1, 3 and 5% of MPP and a control without MPP, was used to make UF soft cheese. The viability, antioxidant value, total solid (TS) content, pH values, acidity, protein and fat contents, and organoleptic properties during storage at 5±2 °C for 21 days of soft cheeses were evaluated. The results revealed that the TPC in methanol extract was the highest and the lowest recorded in acetone extraction, the same trend found in antioxidant and antibacterial activity. The inclusion of both probiotic strains and MPP improved antioxidant activity and cheese quality; symbiotic cheese had considerably higher relative degrees of titratable acidity (TA) and TS than control cheese. The sensory examination revealed that adding the MPP at a ratio of 1% increased the score. Finally, it is proposed that probiotic soft cheese supplemented by MPP as functional food has acceptable composition and good sensory features.