Edible antimicrobial films are an innovation within the biodegradable active packaging concept. They have been developed in order to reduce and/or inhibit the growth of microorganisms on the surface of foods. This study developed an edible antimicrobial film based on yam starch (Dioscorea alata) and chitosan and investigated its antimicrobial efficiency on Salmonella enteritidis. A solution of yam starch (4%) and glycerol (2%) was gelatinized in a viscoamilograph and chitosan added at concentrations of 1%, 3% and 5%. Films with and without chitosan were produced by the cast method. To evaluate the antimicrobial activity of the films, two suspensions of S. enteritidis were used in BHI medium, corresponding to counts of 2 ¥ 10 8 and 1.1 ¥ 10 6 CFU/ml. The suspensions (50 ml) were poured into flasks. The films were cut into 5 ¥ 5 and 5 ¥ 10 cm rectangles to be used at ratios of 1 : 1 (1 cm 2 /ml microorganism suspension) and 2 : 1 (2 cm 2 /ml). The film 30 mm thick on average. As a control, pure chitosan at an amount corresponding to that contained in the 3% and 5% films (5 ¥ 10 cm) was added to flasks containing the microorganism suspension. Also, flasks containing only a suspension of S. enteritidis were used as control. The suspensions, in flasks, were kept at 37°C in a waterbath with agitation. Suspension aliquots were removed every hour for reading the optic density (OD 595 ) and plating onto PCA medium. The results showed that chitosan has a bactericidal effect upon S. enteritidis. Films treated with chitosan at different concentrations showed similar antimicrobial efficiency, in addition to being dependent on diffusion. The chitosan-treated films caused a reduction of one to two log cycles in the number of microorganisms, whereas the pure chitosan presented a reduction of four to six log cycles compared with the control and starch film. The films showed good flexibility.

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A polpa de manga (Mangifera indica L.) tem grande importância como matéria-prima em indústrias de conservas de frutas, que podem produzi-las durante as épocas de safra, armazená-las e reprocessá-las em períodos mais propícios, ou segundo a demanda do mercado consumidor, como doces em massa, geléias, sucos e néctares. Ao mesmo tempo também são comercializadas para outras indústrias que utilizam a polpa de fruta como parte da formulação de iogurtes, doces, biscoitos, bolos, sorvetes, refrescos e alimentos infantis.No Brasil, a legislação (BRASIL, 2000) que trata de polpa ou purês é direcionada ao consumo como bebida, ou seja, avaliado com base nos indicadores do suco de manga. A polpa de frutas é definida como o produto não fermentado, não concentrado, não diluído, obtido de frutos polposos, através de processo tecnológico adequado, com um teor mínimo de sólidos totais proveniente da parte comestível do fruto, devendo apresentar cor amarela, sabor doce, levemente ácido, além de sabor e aroma próprios da fruta.O Regulamento Técnico para Fixação dos Padrões de Identidade e Qualidade para Polpa de Manga (BRASIL, 2000) estabelece parâmetros físico-químicos e microbiológicos como: pH mínimo de 3,30 e máximo de 4,50; sólidos solúveis totais em AbstractUbá mango (Mangifera indicates L. var. Ubá) has excellent flavor qualities and a tasty, yellow and succulent pulp. It contains a high content of soluble solids, around 14 °Brix, acidity of 0.2% as citric acid and ratio 70, besides being rich in potassium and vitamins A and C. The fruit has soft and short fibers, and can be consumed fresh or be industrialized, especially for the production of pulp and juice. This variety possesses an excellent industrialization yield, by greatly reducing processing, with a consequent reduction in the final production costs. Ubá mango supplied to a pulp and juice agroindustry in the Zona da Mata Mineira area had its quality determined through fruit and pulp analyses. During the 2003/2004 harvest period, the Dirty Mangos (DM), as were denominated the fruits that arrived at the industry, presented an average initial count of 7.34 log CFU mesophyllic aerobics/mango. After cleaning, the fruits were called Clean Mangos (CM), and had an average of 5.62 log CFU/mango, presenting an average reduction of 1.72 log cycles. In the 2004/2005 harvest period, the DM presented an average initial count of 7.02 log CFU mesophyllic aerobics/mango and the CM, an average of 5.76 log CFU/mango, with an average reduction of 1.52 log cycles. The mango pulp presented values for pH, total soluble solids, total acidity, total soluble solids/total acidity ratio, total solids and total soluble sugars, in accordance with the legislation requirements. The color coordinates presented values indicating that the pulp has a yellow-orange characteristic color. Keywords: Ubá mango; physical; physico-chemical and microbiological characterisations. ResumoA manga Ubá (Mangifera indica L. variedade Ubá) possui excelentes qualidades de sabor e aroma, além de sua polpa ser amarelada,...

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There is current interest in using biobased materials to produce food packaging that can increase the shelf-lives of fruits and vegetables and minimize food spoilage in supermarkets and at the same time not generating plastic waste that causes long-term disposal problems. A good candidate for such materials is the polysaccharide, such as carboxymethyl cellulose (CMC), which is edible and biodegradable. In this work films were produced from two CMC materials with different degrees of substitution (DS) that encapsulated four different essential oils (eugenol, rosemary oil, coriander oil, and nutmeg oil) that are known to have beneficial properties for food applications. The mechanical properties, opacity, and water vapor permeation were evaluated. In general, the essential oil-embedded CMC with the two DS values behaved rather differently. In particular, the essential oil-embedded CMC with 0.7 DS degree of substitution gave stronger and more flexible films and may be more suited for use in food packaging.