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The tick Rhipicephalus microplus is a parasite of great importance in cattle breeding. It is responsible for huge economic losses. The application of synthetic acaricides is used as a form of control. However, resistant strains have been selected over the years, making it necessary to search for new alternative formulations. The present study aimed to formulate biodegradable films impregnated with the terpenes carvacrol and thymol and evaluate their efficacy on larvae and adults of R. microplus through in vitro tests. The following formulations were prepared: Film 1 (starch based); Film 2 (based on starch and glycerol); Film 1 + Carvarcol or Thymol; Film 2 + Carvarcol or Thymol. Terpenes had a final concentration of 5.0 mg/mL. To evaluate the formulations on larvae, the immersion test was performed by dividing into six groups according to the concentration of terpenes: 5.0, 2.5, 1.25, 0.625, 0.313, 0.156 mg/mL and the control groups: 1% ethanol solution; 10% ethanol solution; Film 1; and Film 2. For the evaluations on adult ticks, ten experimental groups (n = 10) were used: 1) Carvacrol; 2) Film 1 + Carvacrol; 3) Film 2 + Carvacrol; 4) Thymol; 5) Film 1 + Thymol; 6) Film 2 + Thymol; 7) Distilled water; 8) 10% ethanol solution; 9) Film 1; and 10) Film 2. In experimental groups 1-6, carvacrol and thymol (free or incorporated in two different biodegradable film formulations) were evaluated at the same concentration (5.0 mg/mL). Each group of ticks was immersed in their respective solutions for five minutes. The results of the tests on larvae showed that the Film 1 + thymol and Film 2 + carvacrol formulations had the lowest lethal concentrations (0.076 and 0.255 mg/mL, respectively), values up to 9.0-fold lower than the monoterpenes tested outside the formulation. Carvacrol and thymol at the concentrations tested were effective in controlling engorged females with a percentage of 32.2% and 63.8%, respectively. When incorporated into biodegradable film formulations, these monoterpenes showed much greater efficacy. Film 1 + carvacrol and Film 2 + carvacrol with control percentages of 71.6% and 97.2%, respectively, while the formulations Film 1 + thymol and Film 2 + thymol showed values of 96.9% and 100.0%. The tick control activity of the biopolymer formulations with thymol and carvacrol was demonstrated through the high mortality rates of larvae and engorged females of the tick R. microplus. Therefore, the results obtained indicate that these formulations have great potential for tick control mainly because of the percentage of control up to 100% in engorged females in in vitro tests.

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Films based on poly(vinyl alcohol) (PVA) and cationic starch (CS) were combined with different percentages of sorbitol (S; 15.0, 22.5, and 30.0% w v-1) to assess the effect of plasticizer on the films. Spectroscopic analyses confirmed the interaction between them. However, micrographs indicated the formation of sorbitol crystals on the surface of the films, especially at higher sorbitol concentrations. The blends presented low water vapor transmission rate values, reaching (7.703 ± 0.000) g h-1 m-2 (PVA75CS25S15), and low solubility values for the films containing higher CS amounts. The lack of statistical differences in most parameters suggests that no significant gain comes from increasing the amount of sorbitol at percentages higher than 15%. As a coating, the blend PVA75CS25S15 successfully decreased the loss of moisture content in acerolas by 1.15 times (compared to the control), confirming the suitability of this matrix as a fruit coating.

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Cassava starch is one of the most available and cost-effective biopolymers. This work aimed to apply a bibliometric methodology to identify the most impactful scientific data on cassava starch and its residues for food packaging in the last ten years. As a result, an increasing interest in this subject has been observed, mainly in the past five years. Among the 85 selected scientific publications, Brazil and China have been leading the research on starch-based films, accounting for 39 % of the total. The International Journal of Biological Macromolecules was the main scientific source of information. Besides cassava starch, 41.18 % of these studies added other biopolymers, 5.88 % added synthetic polymers, and 4.71 % added a combination of both. Studies analyzed suggested that different modifications in starch can improve films' mechanical and barrier properties. In addition, 52.94 % of articles evaluated the film's bioactivity. Still, only 37.65 % assessed the performance of those films as food packaging, suggesting that more studies should be conducted on assessing the potential of these alternative packages. Future research should consider scale-up methods for film production, including cost analysis, assessment life cycle, and the impact on the safety and quality of a broader range of foods.

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Packaging materials play an essential role in the preservation and marketing of food and other products. To improve their conservation capacity, antimicrobial agents that inhibit bacterial growth are used. Biopolymers such as starch and chitosan are a sustainable alternative for the generation of films for packaging that can also serve as a support for preservatives and antimicrobial agents. These substances can replace packaging of synthetic origin and maintain good functional properties to ensure the quality of food products. Films based on a mixture of corn starch and chitosan were developed by the casting method and the effect of incorporating cellulose nanocrystals (CNC) at different concentrations (0 to 10% w/w) was studied. The effect of the incorporation of CNC on the rheological, mechanical, thermal and barrier properties, as well as the antimicrobial activity of nanocomposite films, was evaluated. A significant modification of the functional and antimicrobial properties of the starch-chitosan films was observed with an increase in the concentration of nanomaterials. The films with CNC in a range of 0.5 to 5% presented the best performance. In line with the physicochemical characteristics which are desired in antimicrobial materials, this study can serve as a guide for the development this type of packaging for food use.

RESUMO

This study aimed to produce and characterized active biodegradable packages by extrusion of cassava starch, biodegradable polyester, plasticizer, and acai extract (EA 0, 1, 2, 3 and 4%) and to evaluate its effects on extra virgin olive oil (EVOO) for 120 days. All analyses were performed at the beginning (day 0) and the end of the experiment (day 120). The oil was characterized for acidity index (IA), peroxide index (IP), thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD), phenolic compounds (PC) and color parameters. The incorporation of EA at the initial time caused increased thickness, mechanical properties, solubility in water and oil in all formulations. The some values of properties increased or decreased, due to the interaction of the stored product and packaging. At the end of the storage period, the values of IA and IP were below the limits established by current legislation. The EVOO showed a gradual decrease in PC from day 1 to day 120, for all treatments.

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Developing biodegradable active films has been a promising green approach to overcoming global concerns over the environmental pollution and human health caused by plastic utilization. This study aimed to develop active films based on chitosan (CS), produced from waste crayfish (Procambarus clarkii) shells enriched with bioactive extract (5-20%) of propolis (PS) and to characterize its properties, envisaging food packaging applications. The chromatographic profile of PS extract confirmed its richness, with 41 phenolic compounds. With increasing extract addition to the chitosan, the thickness of the films increased from 61.7 to 71.7 µm, causing a reduction in the light transmission rate, along with a greenish colour shift. The interactions between PS extract and CS was confirmed by infrared spectroscopy, at the same time that the microstructural integrity of the films was checked on the scanning electron microscopy micrographs. The findings also showed that addition of PS enhanced the films thermal stability and mechanical properties e.g., tensile modulus, yield strength, and stress at break. Besides, it improved the antioxidant and antimicrobial activities. Overall, CS-based composite films seem a promising green alternative to petroleum-based synthetic plastics allowing to extend the shelf life of food products due to their eco-friendly nature.

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Starch is a biopolymer with enormous potential for generating new biodegradable packages due to its easy availability and low cost. However, due to its weak functional properties, limitation of its interaction with some hydroxyl groups and evaluation of blends with other polymers are necessary in order to improve its performance. Glycerol-plasticized acetylated corn starch films were developed using the casting method, and the impact of incorporating chitosan (TPS:CH) in various proportions (75:25, 50:50, and 25:75 v/v) was studied in the present research. The effect of chitosan ratios on the physical, mechanical, water-vapor barrier, and thermal properties of the film was studied. Chitosan-protonated amino groups promoted the formation of intermolecular bonds, improving tensile strength, thermal stability, hydrophobicity, water adsorption capacity, and the gas barrier of starch films. The results show that the film composed of TPS25-CH75 proved to be the best barrier to water vapor; thus, these composite films are excellent choices for developing biodegradable packaging for the food industry.

RESUMO

The objective of this study was to evaluate the application of a biodegradable film, based on grape seed flour extract, for raisin packaging. Physico-chemical characteristics (moisture, total soluble solids, total acidity, pH), total phenolic content and antioxidant activity were evaluated during 182 days of storage at 20 °C, compared to a poly(ethylene) film packaging. After 182 days, the use of biodegradable film increased raisin moisture and pH, decreased total soluble solids and total acidity of raisin compared to the use of poly(ethylene) film. The total phenolic content and antioxidant activity of raisin packed in the biodegradable film were 60.0 and 51.8% higher, respectively, than in poly(ethylene) film. The results showed that the biodegradable film based on seed flour extract is a potential material for active packaging due its contribution to the maintenance of the antioxidant activity of raisin and can be used for their conservation.

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The production of fruit-film packaging has attracted increasing attention in scientific research due to the packaging's environmentally friendly, nontoxic, and edible characteristics. The development of alternative packaging contributes to both minimizing the environmental impacts caused by the large consumption of non-biodegradable plastics and favoring the reduction of postharvest loss/waste of fruit. In addition, these fruit films have the potential to be functional packages due the presence of antioxidant and antimicrobial compounds that can migrate to the food matrix, acting as natural additives. The use of fruit puree to develop biodegradable films can be simpler and more practical than the developed of films from fruit flour or extracts, reducing the time, energy, and resources necessary to prepare the film-forming solution. A better understanding of the mechanical properties, bioactive compounds, and potential applications is interesting in terms of prospecting new specific ways to produce and use these films. In this study, we briefly review the general aspects of fruit puree films, highlighting their characterization for use as food packaging.

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Starch is an excellent alternative to produce packaging materials, however, due to its high hydrophilicity, it is necessary to mix it with other polymers. Chitosan (CTS) is a polymer extracted from shrimp shells and crabs, which can be used to make biodegradable materials. The principal component of biodegradable was corn starch and chitosan, the copolymer pluronic F127 was incorporated in several concentrations and its effect on the water vapor barrier, morphological, thermal, and mechanical properties of the films was evaluated, because its incorporation in the formulation of biodegradable materials could increase its hydrophobicity. The surface of starch-chitosan composite films obtained was more homogeneous and smoother with the increase in the content of pluronic F127. The %S and WVP of the starch-chitosan films decreased from 42 to 3%, and 21 × 10-11 to 3 × 10-14 g. m-1s-1 Pa-1, respectively, with the incorporation of pluronic from 3%, which makes these materials a good alternative for product packaging.

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The incorporation of plant-based extracts into polymer-based coatings is an efficient alternative to increase the shelf-life of stored fruit and to decrease or even prevent bacterial growth. Considering strawberries, it is also important to preserve their high antioxidant activity. Hence, this work evaluated the efficiency of a coating based on native cassava starch (NCS), gelatin, and sorbitol, containing different concentrations of Tetradenia riparia extract, in delaying the ripening process of strawberries stored under refrigerated conditions, and in preventing bacterial growth and antioxidant activity losses. Both concentrations of extract (500 or 1000 µg mL-1) increased the thickness, opacity, and water vapor transmission rate (WVTR) of the films when compared to the film without extract, but decreased the solubility. Even though the film without extract was expected to create a more efficient barrier to the coated fruits, the films containing the extract led to similar results of soluble solids (SS), titratable acidity (TA), and vitamin C. Nevertheless, the extract incorporation improved the control over bacterial growth, and preserved the high antioxidant activity of the strawberries within ten days of storage.

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Cellulose nanofibers (CNFs) were isolated from unripe banana peel by acid hydrolysis, with different acid concentrations (0.1%, 1.0% and 10% v/v), followed by mechanical treatment with high-pressure homogenizer. Banana starch-based films added with CNFs (0.2% w/w) as a reinforcing agent were produced by the casting method. The rheological behavior of aqueous dispersions of CNFs (1.0% w/w) and their effects on the properties of nanocomposite films were investigated. All aqueous dispersions of CNFs showed gel-like behavior and, when incorporated to the films, CNFs improved their water barrier properties and mechanical resistance as demonstrated by the increase in tensile strength and Young's modulus. Moreover, CNFs were well dispersed in the composite matrix. CNFs prepared at higher concentration, followed by mechanical treatment (FNM1 and FNM10), formed films with low moisture (13.66%) and solubility in water (24.1%). Whereas, CNFs prepared at the lowest acid concentration without mechanical treatment (FN0.1) led to films with high elongation at break (30.6%) and good tensile strength (12.3 MPa). Regardless of the used CNFs, all the nanocomposites displayed lower UV/light transmission than control film. The nanocomposite has potential use in food packaging, since the use of CNFs can promote improvements on barrier, optical and mechanical properties. Cellulose nanofibers isolated from agro-industrial residues offer the potential to reinforce composites of biodegradable polymers, producing a value-added material.

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In this study, the effect of chia mucilage (CM) and protein concentrate (CPC) contents on the physicochemical, thermal, mechanical, and optical characteristics of developed films was evaluated. Films were prepared dissolving CM:CPC mixtures (1% w/v) in seven ratios (0:1, 1:4, 1:2, 1:1, 2:1, 4:1, 1:0). Microstructure of treatments with higher CM revealed the formation of polysaccharide granules. A semicrystalline behavior was manifested in 1:0, which decreased as CPC content in the formulations increased. Contact angle values obtained for 1:1 and 2:1 were the highest (61.24° and 62.44°), evidencing less affinity to water than other films. TGA analysis suggest that films showed thermal stability at less than 225 °C. Melting temperatures above 85 °C were found for all films in the evaluated range (50 °C to 200 °C) of DSC analysis. Higher CM concentrations in films increased the force required to break them (13.5 MPa) and their elongation capacity (5.20%). As the CM ratio in formulations was increased, the color difference was lower (ΔE = 27.45), water vapor permeability was higher (10.9 × 10-11  g/m·s·Pa), but transparency was statistically the same for all treatments (6.62 to 7.26). After analyzing all films properties, 2:1 formulation corresponding to 25:75% w/v mixtures of CM:CPC would be the best option for use in food packaging.

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One of the newest areas of using the potential of a microbial association of kefir grains is obtaining a biodegradable film. The research was aimed at creating a packaging material with new properties of suppressing the development of concomitant microflora in dried berries and fruits.

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Water molecules modify the properties of biodegradable films obtained from hydrophilic materials. Most studies dealing with thermal, mechanical and barrier properties of hydrophilic films are carried out under one relative humidity (RH) condition. The objective of this work was to evaluate the effect of the moisture content on the thermal, mechanical and barrier properties of chitosan films under several RH conditions. Microclimates, obtained with saturated salt solutions were used for conditioning samples and the properties of the films were evaluated under each RH condition. Chitosan films absorbed up to 40% of moisture at the higher RH studied. The percentage of elongation and the water vapour permeability increased while tensile strength, Young's modulus and glass transition temperature decreased, when the moisture content increased. The results suggest that the water molecules plasticized the polymer matrix, changing the properties when the films were in contact with high RH environments.

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BACKGROUND: This study aimed to produce and characterize edible films and coatings from fruit and vegetable residue (FVR) flour and potato peel (P) flour. Two coating approaches (immersion and film) were studied on the quality of acerolas. RESULTS: Film-forming solutions (FFS) presented a viscoelastic behavior and a gelation process occurring at 70 °C. Maximum density (1.018 g cm(-3) ), viscosity (44.404 cP) and starch content were obtained for FFS based on 8% FVR flour with 4% P flour. This same film presented enhanced mechanical properties such as tensile strength and elongation at break (0.092 MPa and 36% respectively). Solubility of the films averaged 87%, demonstrating high hydrophilicity. Improved performance was obtained for film-packaged acerolas, which exhibited an increase in shelf life of 50% compared with control fruits. A lower loss of weight was observed for these samples by about 30-57% compared with control fruits, but minor modifications of pH, titratable acidity and soluble solid content occurred during storage. CONCLUSION: This study demonstrated the potential of FVR flour for edible coating and film formulation. Practical application on acerolas constituted a motivating route to evaluate and optimize this process; however, microbiological and sensory analyses are necessary to assess the material acceptability and safety.

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Objetivando reduzir os impactos ambientais decorrentes do acúmulo de plásticos sintéticos, estão sendo desenvolvidas embalagens derivadas de polímeros renováveis, os chamados filmes biodegradáveis. Empregados na cobertura de produtos desidratados e frescos são capazes de conservar suas características sensoriais, valor nutritivo e evitar o desenvolvimento de micro-organismos (MO). Com este intuito, foram produzidos filmes com amido acetilado, gelatina e plastificante impregnados com óleos essenciais de Tetradenia riparia (Hochst.) Codd e Rosmarinus officinalis nas concentrações de 0,25; 0,5; 1; 2 e 3% (em relação à massa total do filme). Os parâmetros avaliados foram a espessura, solubilidade, opacidade e a capacidade de inibição microbiana frente aos micro-organismos Escherichia coli, Staphylococcus aureus e Candida albicans. Após a adição do óleo, observou-se redução na espessura nos filmes contendo R. officinalis quando comparados ao controle negativo (CN). Já nos filmes com T. riparia, os valores foram semelhantes ao CN, indicando melhor compatibilidade entre reagentes dos filmes a esse óleo. As solubilidades desses filmes aumentaram ao incorporar os óleos, exceto nos filmes com 0,25 e 1% do óleo de T. riparia, em que os valores ficaram próximos ao CN. A opacidade dos filmes com óleo de R. officinalis aumentou com o aumento da concentração deste óleo na composição do filme, porém nos filmes com T. Riparia, ocorreu o contrário a opacidade diminuiu com o acréscimo deste óleo nos filmes. Quanto ao filme incorporado com cloranfenicol, nos três parâmetros não houve diferenças significativas ao compará-lo com o CN. No teste microbiológico, para todos os filmes analisados, os MO demonstraram resistência comparados aos halos formados pelo controle positivo. Portanto, novos estudos deverão ser realizados, objetivando aumentar a compatibilidade dos filmes com os óleos, bem como novos óleos poderão ser analisados.

In order to reduce the environmental impacts resulting from the accumulation of synthetic plastic, packaging derived from renewable polymers are being developed, which are known as biodegradable films. Used in dried and fresh products, they are able to retain their sensory characteristics and nutritional value, as well as preventing the development of microorganisms (MO). For this purpose, films with acetylated starch, gelatin and plasticizer impregnated with Tetradenia riparia (Hochst.) Codd and Rosmarinus officinalis essential oils at concentrations of 0.25, 0.5, 1, 2 and 3% (relative to the total weight of the film) have been developed. This paper assessed the thickness, solubility, opacity and the capacity to inhibit Escherichia coli, Staphylococcus aureus and Candida albicans in these films. After the addition of oil, a decrease in the thickness of film incorporated with R. officinalis could be observed when compared to the negative control (NC). However, the film incorporated with T. riparia, the values were similar to the NC, indicating better compatibility between the film reagents and this oil. The solubility of these films increased when the oils were incorporated, except for the films with concentration of 0.25 and 1% of T. riparia oil, in which the values were close to the NC. The opacity of the films with R. officinalis oil increased with the increase in the concentration of oil in the composition of the film. However, in the films with T. riparia, the opposite could be noticed, that is, the opacity decreased with the addition of this oil in the films. For the films with chloramphenicol, there were no significant differences for the three parameters measured when compared to the NC. In the microbiological test, for all films analyzed, the MO showed resistance compared to the inhibition formed by the positive control. Therefore, further studies should be conducted in order to increase the compatibility of the films with the oils, as well as analyzing new oils;

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Biodegradable films were produced using the blown extrusion method from blends that contained cassava thermoplastic starch (TPS), poly(butylene adipate-co-terephthalate) (PBAT) and poly(lactic acid) (PLA) with two different extrusion processes. The choice of extrusion process did not have a significant effect on the mechanical properties, water vapor permeability (WVP) or viscoelasticity of the films, but the addition of PLA decreased the elongation, blow-up ratio (BUR) and opacity and increased the elastic modulus, tensile strength and viscoelastic parameters of the films. The films with 20% PLA exhibited a lower WVP due to the hydrophobic nature of this polymer. Morphological analyses revealed the incompatibility between the polymers used.

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Objetivando reduzir os impactos ambientais decorrentes do acúmulo de plásticos sintéticos, estão sendo desenvolvidas embalagens derivadas de polímeros renováveis, os chamados filmes biodegradáveis. Empregados na cobertura de produtos desidratados e frescos são capazes de conservar suas características sensoriais, valor nutritivo e evitar o desenvolvimento de micro-organismos (MO). Com este intuito, foram produzidos filmes com amido acetilado, gelatina e plastificante impregnados com óleos essenciais de Tetradenia riparia (Hochst.) Codd e Rosmarinus officinalis nas concentrações de 0,25; 0,5; 1; 2 e 3% (em relação à massa total do filme). Os parâmetros avaliados foram a espessura, solubilidade, opacidade e a capacidade de inibição microbiana frente aos micro-organismos Escherichia coli, Staphylococcus aureus e Candida albicans. Após a adição do óleo, observou-se redução na espessura nos filmes contendo R. officinalis quando comparados ao controle negativo (CN). Já nos filmes com T. riparia, os valores foram semelhantes ao CN, indicando melhor compatibilidade entre reagentes dos filmes a esse óleo. As solubilidades desses filmes aumentaram ao incorporar os óleos, exceto nos filmes com 0,25 e 1% do óleo de T. riparia, em que os valores ficaram próximos ao CN. A opacidade dos filmes com óleo de R. officinalis aumentou com o aumento da concentração deste óleo na composição do filme, porém nos filmes com T. Riparia, ocorreu o contrário a opacidade diminuiu com o acréscimo deste óleo nos filmes. Quanto ao filme incorporado com cloranfenicol, nos três parâmetros não houve diferenças significativas ao compará-lo com o CN. No teste microbiológico, para todos os filmes analisados, os MO demonstraram resistência comparados aos halos formados pelo controle positivo. Portanto, novos estudos deverão ser realizados, objetivando aumentar a compatibilidade dos filmes com os óleos, bem como novos óleos poderão ser analisados.(AU)

In order to reduce the environmental impacts resulting from the accumulation of synthetic plastic, packaging derived from renewable polymers are being developed, which are known as biodegradable films. Used in dried and fresh products, they are able to retain their sensory characteristics and nutritional value, as well as preventing the development of microorganisms (MO). For this purpose, films with acetylated starch, gelatin and plasticizer impregnated with Tetradenia riparia (Hochst.) Codd and Rosmarinus officinalis essential oils at concentrations of 0.25, 0.5, 1, 2 and 3% (relative to the total weight of the film) have been developed. This paper assessed the thickness, solubility, opacity and the capacity to inhibit Escherichia coli, Staphylococcus aureus and Candida albicans in these films. After the addition of oil, a decrease in the thickness of film incorporated with R. officinalis could be observed when compared to the negative control (NC). However, the film incorporated with T. riparia, the values were similar to the NC, indicating better compatibility between the film reagents and this oil. The solubility of these films increased when the oils were incorporated, except for the films with concentration of 0.25 and 1% of T. riparia oil, in which the values were close to the NC. The opacity of the films with R. officinalis oil increased with the increase in the concentration of oil in the composition of the film. However, in the films with T. riparia, the opposite could be noticed, that is, the opacity decreased with the addition of this oil in the films. For the films with chloramphenicol, there were no significant differences for the three parameters measured when compared to the NC. In the microbiological test, for all films analyzed, the MO showed resistance compared to the inhibition formed by the positive control. Therefore, further studies should be conducted in order to increase the compatibility of the films with the oils, as well as analyzing new oils;(AU)

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The minimal processing of horticultural products endears the raw material and is convenient to the consumer due to the facility for preparing and consuming. The objective of this work was to develop an active packaging for fresh-cut iceberg lettuce (Lactuca sativa L.) to increase its shelf life. Minimally processing methodology was defined and the product quality was determined by sensorial, physico-chemical and microbiological analysis. The lettuce tree was selected, trimmed, pre-washed, soaked in sanitized water (100ppm of active chlorine) for 15 minutes and centrifuged. The lettuce leafs were packed in polypropylene pots with a sachet containing 1-methylcyclopropene (1-MCP) and sealed with biodegradable starch film. Soon after the processing, the product was stored at 4oC for 12 days. Periodically samples were evaluated in terms of appearance and purchase intention, soluble solids and vitamin C contents, pH, texture, color, weight loss and total count of mesophilic and psicotrofic microorganisms, lactic bacteria, mould and yeast. Using 1-MCP in sachet format did not increase the lettuce shelf life but the minimal processing combined with packaging sealed with biodegradable film is practicable as the product showed good sensorial acceptance, low microbiological counts and shelf life of 5 days at 4oC.

O processamento mínimo de produtos hortícolas agrega valor à matéria-prima e são convenientes ao consumidor, devido à facilidade de preparo e consumo. O objetivo do trabalho foi desenvolver uma embalagem ativa para alface americana (Lactuca sativa L.) minimamente processada visando o aumento da vida útil. Foi definida uma metodologia de processamento mínimo e a qualidade do produto foi acompanhada através de avaliação sensorial, físico-química e microbiológica. As cabeças de alface foram desfolhadas, selecionadas, pré-lavadas, sanificadas (100 ppm de cloro ativo) por 15 minutos e centrifugadas. As folhas foram acondicionadas em potes de polipropileno contendo sachês com 1-metilciclopropeno (1-MCP) e seladas com filme biodegradável de amido. Logo após o processamento, o produto foi armazenado a 4ºC por 12 dias. Periodicamente amostras foram avaliadas sensorialmente (aparência e intenção de compra) e foram determinados os teores de sólidos solúveis e vitamina C, pH, textura, cor, perda de massa e contagem total de microrganismos mesófilos, psicrotróficos, bactérias láticas, bolores e leveduras. O uso de 1-MCP na forma de sachê não aumentou a vida útil da alface em relação ao controle, mas o processamento mínimo associado à embalagem selada com filme biodegradável é uma técnica viável, pois o produto apresentou boa aceitação sensorial, contaminação microbiológica baixa e vida de p