Antimicrobial effects of edible nano-composite based on bean pod shell gum, nano-TiO2, and Mentha pulegium essential oil

Natural antioxidants in edible coatings can modify the structure and improves the functionality and applicabilityof the film in food industries. This study was done to determine the antimicrobial effect of nano-compositebased on bean pod shell gum (4% w/v), TiO2 nano-particles (NPs) (1%–2% w/v) and Mentha pulegiumessential oil (EO) (2%–4% v/v) on five food-borne pathogens in two categories, including Gram positives andthree Gram-negatives bacteria. The antimicrobial activity was tested using disk diffusion test. According to theresults, Gram-positive bacteria were more susceptible than Gram-negative bacteria. Increasing M. pulegiumEO and TiO2 NPs content increased the antimicrobial activity of the edible film based on bean pod shell gum,so that the treatment containing 4% v/v M. pulegium EO and 2% w/v TiO2 NPs led to the highest inhibitionzone (11.8–15.2 mm) compared to treatment containing 2% v/v M. pulegium EO and 1% w/v TiO2 NPs withinhibition zone range of 9.8–11.5 mm. In general, TiO2 NPs and M. pulegium EO improved the functionalproperties, including antimicrobial activity of the edible film based on bean pod shell gum which increases thepotential of films to be used for fresh products.

Impact of Aluminum Oxide and Silica Oxide Nanocomposite on Foodborne Pathogens in Chicken Fillets

Nanotechnology is an innovative technology for improving food quality and safety. Aims: The aim of this study was to evaluate the efficacy of hydroxy propyl methyl cellulose (HPMC) films containing nanoparticles against three foodborne pathogens. Design of the Study: *This study was designed using two nanoparticles i.e. (Al2O3-NPs and SiO2-NPs), edible film (HPMC), and three foodborne pathogens i.e. Bacillus cereus, Staphylococcus aureus, and Salmonella Typhimurium. Both nanoparticles were evaluated against foodborne pathogens as well applied in chicken fillets. Place and Duration: All experiments were done in the Food Technology Department, Benha University, Egypt; Nanomaterial Laboratory, Beni-Suef University, Egypt; and Agricultural Research Center, Egypt and were done within three months. Methodology: The preparation of edible films, the antimicrobial activity, mode of antimicrobial action, challenge study, and scanning electron microscopy had been carried out in different laboratories. As well the mechanical properties of the HPMC films were evaluated. Results: The results obtained from this study showed that the nanoparticles (~80 nm) at 80 ppm were active against Bacillus cereus, Staphylococcus aureus, and Salmonella Typhimurium compared with 20 and 40 ppm. The HPMC films including Al2O3-NPs were active against B. cereus than S. aureus and S. typhimurium, while the SiO2-NPs were more effective against S. typhimurium and B. cereus compared with S. aureus. In challenge studies, HPMC films including Al2O3-NPs and SiO2-NPs at 80 ppm decreased the viability of the three-foodborne pathogens associated with chicken fillets stored at 4±1°C for 15 days, as compared with the control sample. HPMC films incorporated with nanoparticles inhibited the microbial population ~ 2-3 log10 CFU/cm2 over the chicken fillets during storage period. Conclusion: This work indicated that, HPMC films incorporated with Al2O3-NPs and SiO2-NPs (~80 nm) at 80 ppm could be reduce the microbiological loads of the refrigerated chicken fillets.

Desempenho de filmes comestíveis em comparação ao filme de policloreto de vinila na qualidade pós-colheita de mexericas 'Poncã' / Performance of edible films in comparison to the polyvinyl chloride film in the post-harvest tangerines 'Ponkan'

O objetivo do trabalho foi avaliar o efeito de diferentes concentrações de fécula de mandioca na vida útil pós-colheita de frutos 'Mexerica Poncã' durante o armazenamento em temperatura ambiente em substituição ao filme de policloreto de vinila (PVC). Os frutos foram imersos em suspensões aquosas de fécula de mandioca a 0; 1; 2 e 3% (m:v) acrescidas de 0,5mL L-1 de óleo mineral Assist (Bayer Cropscience, da empresa Hoechst Schering AgrEvo UK Ltd. - Inglaterra) ou recobertos com PVC de 14µm de espessura, e armazenados a temperatura ambiente. As amostragens foram realizadas no tempo zero (início do experimento) e a cada dois dias, por oito dias. Foram avaliadas a perda de massa fresca, rendimento de suco, sólidos solúveis (SS), acidez titulável (AT), relação SS/AT e teor de ácido ascórbico. A perda de massa fresca aumentou durante o armazenamento, sendo mais acentuada na dose de 2%. A redução no teor de ácido ascórbico foi maior nos frutos recobertos com filme de PVC. A concentração de fécula de mandioca a 1% foi a que proporcionou melhores resultados quanto à manutenção da qualidade físico-química de frutos de 'Mexerica Poncã' durante oito dias de armazenamento.

The objective of this study was to evaluate the effect of different concentrations of cassava starch in postharvest life of fruits 'Tangerine Poncã' during storage at room temperature instead the film of polyvinyl chloride (PVC). The fruits were immersed in aqueous suspensions of cassava starch at 0, 1, 2 and 3% (m/v) plus 0.5mL L-1 a mineral oil Assist (Bayer CropScience, company Hoechst Schering AgrEvo UK Ltd. - Inglaterra) and the film of polyvinyl chloride (PVC) of 14µm thick, and stored at room temperature. The samples were collected at time zero (day of the assembly of the experiment) and then every two days. We evaluated the weight loss, juice yield, soluble solids (SS), titratable acidity (TA), SS / TA and ascorbic acid. The weight loss increased during storage, being more pronounced at a dose of 2%. The reduction in ascorbic acid content was higher in fruits covered with PVC film. The concentration of cassava starch to 1% was the highest values for the maintenance of physical and chemical quality of fruits of 'Mexerica Poncã' during eight days of storage.