Skip to main content
ARS Home » Pacific West Area » Albany, California » Western Regional Research Center » Healthy Processed Foods Research » Research » Publications at this Location » Publication #297413
Title: Optimization of antimicrobial and physical properties of alginate coating containing carvacrol and methyl cinnamate for strawberry application

Author
item PERETTO, GRETA - Universita Di Padova
item Du, Wen-Xian
item Avena-Bustillos, Roberto
item Berrios, Jose
item SAMBO, PAOLO - Universita Di Padova
item McHugh, Tara

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/9/2014
Publication Date: 1/9/2014
Publication URL: http://dx.doi.org/10.1021/jf4042886
Citation: Peretto, G., Du, W., Avena Bustillos, R.D., Berrios, J.D., Sambo, P., McHugh, T.H. 2014. Optimization of antimicrobial and physical properties of alginate coating containing carvacrol and methyl cinnamate for strawberry application. Journal of Agricultural and Food Chemistry. DOI: 10.1021/jf4042886.

Interpretive Summary: The effect of the natural essential oils carvacrol (0.25 – 0.5 % w/w) and methyl cinnamate (0.5 - 2.5 % w/w), were added to alginate (carbohydrate from brown algaeas) to make coating solutions with the purpose to improve the antimicrobial and physical properties of the coating. Antimicrobial activity against a pathogenic bacteria (Escherichia coli O157:H7) and a mold (Botrytis cinerea) was evaluated, as well as the turbidity, viscosity and withish index (Wi) of alginate coating. These determinations were selected as the coating was designed to be applied on fresh strawberries. The results of the study showed that the antimicrobial activity against the bacteria E. coli increased with an increase in carvacrol concentration, whereas inhibition of the mold B. cinerea growth was affected by both carvacrol and methyl cinnamate. Physical properties of the coating were also affected by the concentrations of the antimicrobial compounds. The overall optimum concentrations were found to be 0.98 % (w/w) carvacrol and 1.45 % (w/w) methyl cinnamate.

Technical Abstract: Response surface methodology (RSM) was used to evaluate the effect of different concentrations of carvacrol (0.25 – 0.5 % w/w) and methyl cinnamate (0.5 - 2.5 % w/w), natural active compounds, in alginate coating solutions to improve the antimicrobial and physical properties of the coating. Antimicrobial activity against Escherichia coli O157:H7 and Botrytis cinerea, turbidity, viscosity and withish index (Wi) of alginate coating were selected as response variables, as the coating was designed to be applied on fresh strawberries. The results from analysis of variance (ANOVA) showed the significant fitting of all responses to the quadratic model. Antimicrobial activity against E. coli increased along with carvacrol concentration, whereas inhibition of B. cinerea growth was affected by both carvacrol and methyl cinnamate. Physical properties of the coating were also affected by the concentrations of the antimicrobial compounds. The overall optimum regions, determined by desirability function, were found to be 0.98 % (w/w) carvacrol and 1.45 % (w/w) methyl cinnamate. .