Cinnamaldehyde, a natural preservative that can non-specifically deactivate foodborne pathogens, was successfully incorporated into fish skin gelatin (FSG) solutions and blow spun into uniform nanofibers. The effects of cinnamaldehyde ratios (5–30%, w/w FSG) on physicochemical properties of fiber-forming emulsions (FFEs) and their nanofibers were investigated. Higher ratios resulted in higher values in particle size and viscosity of FFEs, as well as higher values in diameter of nanofibers. Loss of cinnamaldehyde was observed during solution blow spinning (SBS) process and cinnamaldehyde was mainly located on the surface of resultant nanofibers. Nanofibers all showed antibacterial activity by direct diffusion and vapor release against Escherichia coli O157:H7, Salmonella typhimurium, and Listeria monocytogenes. Inhibition zones increased as cinnamaldehyde ratio increased. Nanofibers showed larger inhibition effects than films prepared by casting method when S. typhimurium was exposed to the released cinnamaldehyde vapor, although films had higher remaining cinnamaldehyde than nanofibers after preparation. Lower temperature was favorable for cinnamaldehyde retention, and nanofibers added with 10% cinnamaldehyde ratio showed the highest retention over eight-weeks of storage. Results suggest that FSG nanofibers can be prepared by SBS as carriers for antimicrobials.
11 September 2012 in International Journal of Food Science and Technology
Volatile constituents of Baikal skullcap (Scutellaria baicalensis Georgi) flowers were isolated by solid-phase microextraction (SPME) and analyzed by GC and GC-MS. A total of 64 constituents was identified (constituting 57.1 - 89.9 % of the total area), 13 of which were tentatively identified. β-Caryophyllene (22.3 - 41.5 %), germacrene D (12.4 - 27.5 %), δ-cadinene (3.1 - 5.4 %), γ-muurolene (1.9 - 3.4 %), γ-cadinene (1.6 - 3.1 %), α-humulene (1.6 - 2.6 %), α-copaene (1.4 - 2.3 %), α-muurolene (1.0 - 2.6 %), bicyclogermacrene (1.1 - 2.1 %) and 3-octanone (0.9 - 3.0 %) were the major constituents of the flower volatiles. A small amount (0.5 %) of the uncommon volatile, 2-(methylamino) benzaldehyde was detected in one of the samples.