Effect of Kinnow (Citrus nobilis × C. deliciosa) Peel Oil Coating on the Shelf Stability and Antioxidant Potential of Cheddar Cheese

Abstract

Kinnow peel oil has been reported to possess antimicrobial and antioxidant activities due to presence of many bioactive compounds. Therefore, the experiments reported in this research paper aimed to investigate the shelf stability and antioxidant potential of Cheddar cheese coated with Kinnow peel oil at various concentrations (0.2%, 0.4%, and 0.6%). The physicochemical characteristics, microbial counts, antioxidant potential, and sensory acceptability of Cheddar cheese were evaluated during ripening (up to 9 months, 4°C). The titratable acidity (%), pH, moisture (%), fat (%), protein contents (%), and soluble nitrogen (SN, %) of Cheddar cheese investigated in the present study showed significant $\left(p<0.05\right)$ variations among treatments during ripening. The maximum plate counts (8.36 Log cfu·g−1) were observed in control cheese (T0) ripened for 3 months whereas T3 (9 months ripened) showed the minimum counts (5.04 Log cfu·g−1) among all the treatments. The maximum (3.76 Log cfu·g−1) yeast and mold counts were observed in T0 cheese ripened for 9 month whereas the respective samples of T3 showed the lowest values (2.89 Log cfu·g−1) among all the treatments. The surfaces of Cheddar cheese coated with 0.6% Kinnow peel (T3) did not show any visible signs of yeast and molds. The maximum (366.56 mg GAE/100 g) total phenolic contents were observed in T3 ripened for 6 months. The maximum values (1995.02 mM TE/100 g) of DPPH radical scavenging activity were observed in T3 ripened for 6 months. Similarly, T3 obtained the highest sensory scores among all the treatments. Hence, it was concluded that Kinnow peel oil significantly improved antioxidant potential, sensory perception, and shelf stability of Cheddar cheese.