Ph.D. Dissertation:

mization of extraction conditions and characterization of physical ٫mechanical and Antimicrobial properties of edible film incorporated with caryophillum aromaticcus essential oil ( CAO ) from Caspian White fish (Rutilus frisii Kutum) scale

SALAMGelatin represents a major source of high quality protein with many applications in food, pharmaceutical and cosmetics industries. By-products from fish processing are potential sources of collagen. The physical, chemical and rheological properties of gelatin or collagen depend on their sources as well as the extraction conditions. Response surface methodology (RSM) with three parameters was conducted to determine the optimum extraction conditions of gelatin from caspian white fish scale. A Box-Behnken design was used to study the combined effects of NaOH concentration (0.3-0.9 %, X1), soaking time (60-180 minute, X2) and extraction temperature (30-50 oC, X3) were determined. Gel strength (g) and viscosity (cP) were chosen as responses. The results showed the optimum conditions at NaOH of concentration 0/42 %, a treatment time of 120/94 minutes and extraction temperature of 37/20 oC. The predicted responses including gel strength and viscosity were 145 g and 2.20 cP respectively.Biodegradable protein-based film was developed by incorporating clove essential oil (CAO) into caspian white fish scale (CWFS) at level of 0.5%, 1% and 1.5% v/v. Gelatin ?lms incorporated with clove essential oil (CAO) at various concentrations were prepared and characterised. Incorporation of CAO at 0-1/5% (w/w protein) resulted in the decreases in tensile strength (TS) of the ?lms. Water vapour permeability (WVP) was increased in ?lm added with CAO at level higher than 0/5 % (P < 0.05). In other hand, film solubility and L* values decreased, and the ?lms had the lowered light transmission in the visible range when CAO were incorporated. Films incorporated with CAO showed inhibitory effect in a concentration dependent manner against Escherichia coli, Listeria monocytogenes, Staphylococcus aureus and Salmonella typhimurium. Scanning electron micro- scopic (SEM) images revealed the presence of micro-pores in the essential oil incorporated ?lms, which contributed to physical properties of the resulting ?lms. Thus, gelatin ?lms incorporated with CAO can be used as active packaging, but the properties must be modi?ed.

Keywords: vity Gelatin, Biodegradable protein-based film, Caspian white fish scale (CWFS), Antimicrobial ac,