Production of Biodegradable Film from Soy Protein and Essential Oil of Lemon Peel and Use it as Cheese Preservative

Soy protein with essential oil of lemon peel was used to produce abiodegradable film, which showed inhibition activity against some species of selectedbacterial strains. The films were white cheese coating and studied for its biodegradationin the soil. The percentage of soy protein extract was 15% (W: W) while the percentageof lemon peel essential oil was 3% (V: W). The GC-MS result of lemon peel essentialoil consisted of 38 compounds, of which the main compound is D-Limonene in 63.43%.The films produced showed inhibition activity against both Gram-positive and Gramnegativebacteria. Inhibition activity was highest against Staphylococcus aureus (22 mmzone), while E. coli O157: H7 had the lowest inhibition (18mm) when 0.1mL ofessential oil with 10mL film mixed. The coating process of white cheese reduced thetotal microbial population (CFU/g) during 30 days of storage time. The TCB, TC, STand MY of cheese coating were 4.28, 1.53, 1.62 and 1.33 log. CFU/g respectively after30 days compared to the cheese non-coating samples, with 6.53, 2.51, 3.17 and 1.81log. CFU/g, respectively. The biodegradation in soil was 97 and 72% for soy proteinfilm and soy protein film with lemon peel essential oil after 35 days.