Using Some Essential Oils and Chitosan Nanoparticles to Preserve Soft Cheese

Our current study focused on utilizing natural preservatives as essential oils (clove, thyme, and rosemary) and EOs-chitosan nanoparticles (NPs) that exhibit antimicrobial effects against several bacteria, yeast, and mold). The electrical charge and particle size of NPs were determined. The EOs and EO-chitosan NPs antimicrobial action against some spoilage, pathogenic bacteria, and fungi were detected for MIC, MBC, and MFC. Then, EOs and EOs-chitosan NPs were inoculated separately in examined soft cheese samples. They were analyzed for titraTable acidity (T.A%), microbiological examination, and sensory evaluation at production time and weekly until signs of spoilage were detected. The EO-chitosan NPs showed higher antimicrobial activity than crude forms, especially clove-chitosan NPs recorded highest, followed by thyme and rosemary EO-chitosan NPs, clove EO was recorded lowest MIC (0.1 mg/mL) as relative to other crude EOs while (0.01 mg/mL) for clove and thyme-chitosan NPs recorded lowest as relative to others. TitraTable acidity increased gradually during storage time. Total coliform, aerobic spore formers, psychotropics, and listeria monocytogenes could not be found in every examined sample. The cheese group fortified with rosemary-chitosan NPs at 0.04% showed highest sensory scores with extending cheese shelf life up to 84 days, while cheese groups fortified with clove-chitosan NPs at 0.04% extended their shelf life up to 105 days with accepted organoleptic scores. unlike control and crude oil-fortified cheese groups, EOs-chitosan NPs showed better antimicrobial activity than crude ones and could be applied for soft cheese preservation and extending shelf life without affecting sensory quality.