Hemp (Cannabis sativa) stalk fibres from industry residues were incorporated into polybutylene ad... more Hemp (Cannabis sativa) stalk fibres from industry residues were incorporated into polybutylene adipate terephthalate, a synthetic biodegradable polyester, to produce films and paper coatings. The lignocellulosic components and the chemical composition of the fibres were analysed, and the results highlight the bioactivity due to cannabinoids, alkanoids, and lignin, among others, making the fibres attractive for active food packaging. The incorporation, without chemical modification, of 2% (w/w) hemp in the PBAT matrix increased the water vapour permeability of PBAT around 22%. The impact on mechanical properties was determined, and the results show that the PBAT/hemp film is less stretchable but stronger than the pure PBAT film. The incorporation of hemp enhanced significantly the compostability of PBAT. The PBAT/hemp films and paper coatings composted two times faster than those using pure PBAT.
Background: In recent years there have been significant advancements in the understanding of mine... more Background: In recent years there have been significant advancements in the understanding of mineral oil hydrocarbons (MOH) in foods and their potential risk to health. However, important gaps in knowledge remain, such as the lack of validated and standardized analytical methods for relevant food matrices and gaps in assessing the risk for consumers' health. Scope & approach: A workshop was organized by the European Branch of the International Life Science Institute to identify knowledge gaps in analytical methods, assessment of exposure, hazard characterisation, and risk assessment of MOH. This work captures the outcome of the workshop and builds upon it by combining the perspectives of the participants with an updated review of the literature to provide a roadmap for future management of the topic. Key findings and conclusions: Most participants to the workshop agreed that the key issue underlying many of the knowledge gaps in the field of MOH risk analysis and management is the lack of standardized, validated analytical methods able to assure good inter-laboratory reproducibility and to enable understanding of MOH occurrence in foods. It has been demonstrated that method EN 16995 used for MOH determination in vegetable oils and fats is not reliable below 10 mg/kg of food. There is also a need for confirmatory methods that provide a detailed characterization of the unresolved complex mixture observed from one-dimensional chromatographic methods. This is required to enable adequate substance identification and quantification for input into risk assessment. A major gap in the exposure estimation is the limited number of surveys covering a wide range of foods and enough samples to detect major sources of contamination other than packaging in paperboard. Data on concentration of MOH fractions in human body needed to determine internal exposure estimates is scarce. Data relating concentration in tissues with personal data, lifestyle, food intake and the use of cosmetics are needed to clarify the complex system of distribution of MOSH in the body and to possibly establish relationship between external and internal exposure. Additional toxicological studies to better characterize the hazards of relevant MOH are required for a better human health risk assessment.
This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Pro... more This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process PKR, EC register number RECYC009. The input of the PKR is washed and dried PET flakes originating from collected post-consumer PET bottles containing no more than 5 % of PET from non-food consumer applications. Through this process, dried flakes are extruded into pellets which are then pre-crystallised before being fed to a batch solid state polymerization (SSP) reactor where high temperature and long residence time are applied under vacuum. After having examined the challenge test provided, the Panel concluded that the decontamination at SSP batch reactor is the critical step that determine the decontamination efficiency of the process. The operating parameters to control the performance of this critical step are well defined and are the temperature, the pressure and the residence time. The operating parameters of th...
This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Pro... more This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process Holfeld Diamat (EC register number RECYC076) which is based on the Diamat ® technology. The input of the process is washed and dried PET flakes originating from collected post-consumer PET containers, mainly bottles, containing no more than 5 % of PET from nonfood consumer applications. Through this process, post-consumer washed and dried PET flakes are mixed up to 50 % with virgin PET flakes before being heated in a crystallisation reactor (step 2) and extruded under vacuum into sheets (step 3). After having examined the challenge tests provided, the Panel concluded that the decontamination in the two consecutive extruders step 3 is the critical step for the decontamination efficiency of the process. The operating parameters to control its performance are well defined and are the temperature, the pressure and the residence time. The operating parameters of these steps in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.15 μg/kg food derived from the exposure scenario for toddlers. Therefore, the recycled PET obtained from the process Holfeld Diamat intended for the manufacture of recycled thermoformed trays and containers made with up to 50 % recycled post-consumer PET and intended for contact for long term storage at room temperature with all types of foodstuffs except packaged water is not considered of safety concern.
This paper provides an overview of the fundamental aspects pertaining an effective circular packa... more This paper provides an overview of the fundamental aspects pertaining an effective circular packaging. The main challenges of food packaging systems to comply with the principles of circular economy are addressed. A perspective of the technical issues that drive packaging developments is given, and the main barriers and limiting factors for packaging waste reduction, reusing, and recycling are discussed, particularly as applied to plastic packaging. The state-of-art of recycling plastics for food contact is presented, as well as the gaps for safety assurance. The relevance of consumer and the impact on the whole chain is discussed under the framework of citizens motivation, ability, and opportunity to engage the different measures. Finally, the main measures under the scope of the packaging and waste regulation, and foreseen amendments, and of the plastics recycling directive are briefly presented.
Smart Packaging Technologies for Fast Moving Consumer Goods, 2008
Traditional packaging has contributed greatly to the early development of food distribution syste... more Traditional packaging has contributed greatly to the early development of food distribution systems. However, it is no longer sufficient because today's society became increasingly complex. Innovative packaging with enhanced functions is constantly being sought in response to the consumer demands for minimally processed foods with fewer preservatives, increased regulatory requirements, market globalization, concern for food safety and the recent threat of food bioterrorism [1]. Active packaging (AP) and intelligent (smart) packaging (IP) are becoming increasingly popular among researchers and industry. Apparently there is no common, clear and unequivocal definition of these two types of system. The legislation [2] presents the following definitions: 'Active food contact materials and articles means materials and articles that are intended to extend the shelf-life or to maintain or improve the condition of packaged food; they are designed to deliberately incorporate components that would release or absorb substances into or from the packaged food or the environment surrounding the food'. 'Intelligent food contact materials and articles means materials and articles which monitor the condition of packaged food or the environment surrounding the food'. Active packaging is associated with the preservation and protection function and it refers to systems that are able to change the conditions the product is exposed to. Examples include oxygen absorbers, materials with permeability depending on temperature, antimicrobial materials, etc. Smart or intelligent packaging is associated with communication: a system capable of detecting, sensing, recording, tracing, communicating, and applying science logic, to facilitate
Strawberries purées are incorporated in foods and subjected to pH modulation according to the exp... more Strawberries purées are incorporated in foods and subjected to pH modulation according to the expected final food matrix. The effect of pH on strawberry polyphenols stored at 4 and 23°C for 90 days was evaluated. Total antioxidant activity and total phenolics content were only affected by time according to a first order model. The pH 4.5 induced higher decrease in (À)-epigallocatechin gallate (71% and 79%) and quercetin-3-glucoside (29% and 36%), for both storage temperatures. For pH 2.5 and 3.0, ellagic acid increased 84% for 4°C and 185% for 23°C. Anthocyanins concentration changes along storage were well described by first order model. The pH value of 2.5 presented the lower kinetic constant rate where cyanidin-3-glucoside, pelargonidin-3-glucoside and pelargonidin-3-rutinoside had a k = 0.04, 0.05 and 0.03 day À1. Lower storage temperature (4°C) and lower pH (2.5) were the best condition for the preservation of polyphenols in pasteurized strawberry during a 90-day storage period.
It is recognised that chemicals from packaging and other foodcontact materials can migrate into t... more It is recognised that chemicals from packaging and other foodcontact materials can migrate into the food itself and thus be ingested by the consumer. The monitoring of this migration has become an integral part of ensuring food safety. This article reviews the current knowledge on the food safety hazards associated with packaging materials together with the methodologies used in the assessment of consumer exposure to these hazards. Special attention is given to the most promising approaches for exposure assessment and to the technical and other barriers which need addressing.
The use of probabilistic approaches in exposure assessments of contaminants migrating from food p... more The use of probabilistic approaches in exposure assessments of contaminants migrating from food packages is of increasing interest but the lack of concentration or migration data is often referred as a limitation. Data accounting for the variability and uncertainty that can be expected in migration, for example, due to heterogeneity in the packaging system, variation of the temperature along the distribution chain, and different time of consumption of each individual package, are required for probabilistic analysis. The objective of this work was to characterize quantitatively the uncertainty and variability in estimates of migration. A Monte Carlo simulation was applied to a typical solution of the Fick's law with given variability in the input parameters. The analysis was performed based on experimental data of a model system (migration of Irgafos 168 from polyethylene into isooctane) and illustrates how important sources of variability and uncertainty can be identified in order to refine analyses. For long migration times and controlled conditions of temperature the affinity of the migrant to the food can be the major factor determining the variability in the migration values (more than 70% of variance). In situations where both the time of consumption and temperature can vary, these factors can be responsible, respectively, for more than 60% and 20% of the variance in the migration estimates. The approach presented can be used with databases from consumption surveys to yield a true probabilistic estimate of exposure.
ABSTRACT Respiratory behavior of fresh-cut ‘Rocha’ pear suggests that optimization of O2 concentr... more ABSTRACT Respiratory behavior of fresh-cut ‘Rocha’ pear suggests that optimization of O2 concentration inside modified atmosphere packages (MAP) is of limited benefit. To test this hypothesis, packages were designed to achieve three equilibrium O2 partial pressures. Fresh-cut ‘Rocha’ pear was treated with 250 mM calcium ascorbate solutions buffered at pH 3.0 and pH 7.0, packaged under the three MAP conditions, and stored at 5 °C for 20 d. Actual O2 levels (mean ± confidence interval at 95%) during the experiment were 16.7 ± 0.2, 1.8 ± 0.2 and 0.25 ± 0.04 kPa with corresponding CO2 levels of 1.3 ± 0.1, 4.3 ± 0.2 and 6.5 ± 0.4 kPa. Changes in quality attributes related to fruit metabolism, namely firmness, titratable acidity, pH, and soluble solids content were not affected by O2 levels. Overall changes in water activity, levels of ascorbate, and microbial growth were also independent of O2 levels. Oxygen partial pressure inside the packages affected browning, which was more intense at 16.7 kPa O2. Sensory analyses performed after 8 d in storage confirmed that panelists perceived the differences in color but did not detect differences in firmness or taste among the samples under different O2 levels. Browning was more intense at pH 3.0 than at pH 7.0 but the kinetics of other quality attributes were not affected by pH. No significant improvements of quality attributes dependent on the physiology of respiration of fresh-cut ‘Rocha’ pear can be obtained by reducing O2 partial pressure inside the packages.
The determination of the oxygen transmission rate (OTR) through closures in glass bottles is beco... more The determination of the oxygen transmission rate (OTR) through closures in glass bottles is becoming increasingly important for quality control of different batches and for development purposes. The Mocon method for measuring OTR is globally accepted and used in different applications. However, one of the major drawbacks this method presents when applied to bottle/closures systems is the long time required to obtain stable measurements when 40 mm long closures are tested. This paper describes a method to obtain OTR values with samples of reduced thickness with much shorter measurements time, since the condition of steady state during measurements is achieved faster and compares the estimated full-length commercial closure OTR with experimental values.
The mathematical modeling of migration of additives from plastics to food simulants was studied u... more The mathematical modeling of migration of additives from plastics to food simulants was studied using experimental data published in the literature, following two routes: the conventional approach using the solution of Fick's 2nd law, and a kinetic model based on the Weibull distribution function. The objective of this comparison was to permit using a mathematically simpler model equally able to describe migration data, and that could have a generally wider applicability by describing situations more complex than those that simple diffusional phenomena can describe. The relationship between the parameters of the two models was analyzed by regression of data generated by Fick's law using the Weibull model. The results show that the time constant parameter is related to the diffusion coefficient and the material thickness.
The goal of this research effort was to assess the efficacy of edible films produced from whey pr... more The goal of this research effort was to assess the efficacy of edible films produced from whey protein isolate (WPI) and glycerol, including incorporation of lactic acid (LA) and propionic acid (PRO), chitooligosaccharides with nominal MW of 3 kDa (COS) and natamycin (NA) as antimicrobial agents. Their features were evaluated in vitro via agar diffusion and viable cell counting, against spoilage microflora often found contaminating cheese surfaces. The effect of incorporating the aforementioned compounds upon thickness, moisture content (MC), solubility (S), density (ρ s), water activity (a w) and water vapor permeability (WVP), as well as upon tensile and optical properties of those films were also evaluated. Films formulated with LA, PRO or COS exhibited antimicrobial activity against all microorganisms tested, yet the viable cell count assay was more sensitive and reproducible. COS was the most active against Gram-negative bacteria, whereas LA was the most active against Gram-positive ones. NA was not active against bacteria, but displayed the strongest effect against yeasts. Incorporation of said antimicrobial compounds did not significantly (pN 0.05) affect film thickness, yet it significantly (p b 0.05) reduced tensile strength (TS). Incorporation of LA and NA in particular did not significantly (pb 0.05) affect MC, S, ρ s , WVP, elongation at break (EB) and Young's modulus (YM) values; however, a statistically significant increase (pb 0.05) of MC, S and WVP, together with a statistically significant decrease (p b 0.05) of ρ s were attained upon incorporation of PRO or COS. Moreover, PRO produced the highest variation (pb 0.05) in EB, TS and YM, whereas COS produced the highest change (pb 0.05) in optical properties.
The migration of chemicals from packaging materials into foods is an important issue in food safe... more The migration of chemicals from packaging materials into foods is an important issue in food safety and quality. European legislation sets specific migration limits which compliance must be assessed, surveyed and controlled by industry and authorities. Recently, the new Regulation UE 10/2011 included a new simulant-the Modified Polyphenylene Oxide (Tenax Ò) for solid dry foods. The objective of this work was to compare the migration kinetics of two antioxidants into Tenax Ò as compared to rice at 3 temperatures: 23, 40 and 70 C. The application of two different solutions of the 2nd Fick's law to describe and simulate the migration of the migrants to the present systems was studied. Diffusion coefficients ranged between 4.80E-13 and 2.84E-11 cm 2 /s for the migration into Tenax Ò and between 6.90E-18 and 4.33E-17 cm 2 /s for the migration into rice. The partition coefficients ranged between 6 and 29 for Tenax Ò and were over 1000 for rice. The activation energy for the migration into rice was half of that for Tenax Ò. The models described relatively well the experimental data (ε < 12% and < 30% for rice and Tenax Ò , respectively). Results indicate that the food simulant tends to overestimate migration values and thus can be safely used to assess materials compliance when materials are intended to contact with rice. However, results also indicate that Tenax Ò is a much more severe simulant in representing rice.
The migration of components from paper into Tenax Ò was studied to determine the influence of mol... more The migration of components from paper into Tenax Ò was studied to determine the influence of molecular size and chemical character of the migrant and the influence of paper characteristics in the migration process. The Weibull model was applied because Fick's 2nd law of diffusion gave poor fits in some cases. The migration pattern depended on the migrants molecular size and was independent of temperature in the studied range. The migration rate decreased with the migrant molecular size. The influence of the migrants character (polarity and vapour pressure) on the migration behaviour was also studied: nonpolar migrants with high vapour pressure presented low relative migration values and polar migrants presented high values of relative migration. Results indicated that the apparent partition coefficient between paper and the simulant Tenax Ò increased with the migrant vapour pressure and with both the paper grammage and the recycled pulp content.
and-conditions-of-access.pdf This article may be used for research, teaching and private study pu... more and-conditions-of-access.pdf This article may be used for research, teaching and private study purposes. Any substantial or systematic reproduction, redistribution , reselling , loan or sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material.
This paper presents an integrated approach to estimate exposure of Portuguese population to phtha... more This paper presents an integrated approach to estimate exposure of Portuguese population to phthalates as a contaminant originating from paperboard packaging. The approach combined data of migrant concentration in the foods resulting from a stochastic simulation, with consumption data of food packaged in paperboard. The results from the exposure model were validated with experimental values actually found in the food. A short surveillance exercise was conducted with samples collection from the market shelves to identify and quantify the phthalates present in the packages and in the food. The distribution of values for the di-butyl phthalate concentration in the packages was used as input of the initial concentration in the Weibull model to estimate the concentration of this phthalate in the foods. This distribution of occurrence data was then combined with the packaging usage data in a probabilistic simulation with the Monte Carlo sampling method. Exposure values ranged between 0 and 8.95 µg/day.Kg bw , a value close to the tolerable daily intake established by EFSA-10 µg/day.Kg bw. However, the 97.5 th percentile and the average were, respectively, 1.82 and 0.44 µg/day.Kg bw , indicating that further refinement of the estimates is not necessary. Other phthalates were also detected in the packaging samples: di-isobutyl phthalate and di-ethylhexyl phthalate. This latter was present in all packaging samples collected and was detected in a few food samples at values requiring further investigation.
Critical Reviews in Food Science and Nutrition, 2008
The migration of chemicals from food contact materials into foods is an important issue in food s... more The migration of chemicals from food contact materials into foods is an important issue in food safety. The assessment of materials compliance with regulations includes migration monitoring for many monomers and additives. However, it is recognized that predictive mathematical modelling can be used in many cases, to avoid or to reduce the effort on migration experiments. This article reviews the approaches followed to apply mathematical models to migration, particularly the models used, the approaches to estimate model parameters, and the systems used to experimentally validate the models. Conclusions on the issues requiring further research are drawn.
Hemp (Cannabis sativa) stalk fibres from industry residues were incorporated into polybutylene ad... more Hemp (Cannabis sativa) stalk fibres from industry residues were incorporated into polybutylene adipate terephthalate, a synthetic biodegradable polyester, to produce films and paper coatings. The lignocellulosic components and the chemical composition of the fibres were analysed, and the results highlight the bioactivity due to cannabinoids, alkanoids, and lignin, among others, making the fibres attractive for active food packaging. The incorporation, without chemical modification, of 2% (w/w) hemp in the PBAT matrix increased the water vapour permeability of PBAT around 22%. The impact on mechanical properties was determined, and the results show that the PBAT/hemp film is less stretchable but stronger than the pure PBAT film. The incorporation of hemp enhanced significantly the compostability of PBAT. The PBAT/hemp films and paper coatings composted two times faster than those using pure PBAT.
Background: In recent years there have been significant advancements in the understanding of mine... more Background: In recent years there have been significant advancements in the understanding of mineral oil hydrocarbons (MOH) in foods and their potential risk to health. However, important gaps in knowledge remain, such as the lack of validated and standardized analytical methods for relevant food matrices and gaps in assessing the risk for consumers' health. Scope & approach: A workshop was organized by the European Branch of the International Life Science Institute to identify knowledge gaps in analytical methods, assessment of exposure, hazard characterisation, and risk assessment of MOH. This work captures the outcome of the workshop and builds upon it by combining the perspectives of the participants with an updated review of the literature to provide a roadmap for future management of the topic. Key findings and conclusions: Most participants to the workshop agreed that the key issue underlying many of the knowledge gaps in the field of MOH risk analysis and management is the lack of standardized, validated analytical methods able to assure good inter-laboratory reproducibility and to enable understanding of MOH occurrence in foods. It has been demonstrated that method EN 16995 used for MOH determination in vegetable oils and fats is not reliable below 10 mg/kg of food. There is also a need for confirmatory methods that provide a detailed characterization of the unresolved complex mixture observed from one-dimensional chromatographic methods. This is required to enable adequate substance identification and quantification for input into risk assessment. A major gap in the exposure estimation is the limited number of surveys covering a wide range of foods and enough samples to detect major sources of contamination other than packaging in paperboard. Data on concentration of MOH fractions in human body needed to determine internal exposure estimates is scarce. Data relating concentration in tissues with personal data, lifestyle, food intake and the use of cosmetics are needed to clarify the complex system of distribution of MOSH in the body and to possibly establish relationship between external and internal exposure. Additional toxicological studies to better characterize the hazards of relevant MOH are required for a better human health risk assessment.
This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Pro... more This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process PKR, EC register number RECYC009. The input of the PKR is washed and dried PET flakes originating from collected post-consumer PET bottles containing no more than 5 % of PET from non-food consumer applications. Through this process, dried flakes are extruded into pellets which are then pre-crystallised before being fed to a batch solid state polymerization (SSP) reactor where high temperature and long residence time are applied under vacuum. After having examined the challenge test provided, the Panel concluded that the decontamination at SSP batch reactor is the critical step that determine the decontamination efficiency of the process. The operating parameters to control the performance of this critical step are well defined and are the temperature, the pressure and the residence time. The operating parameters of th...
This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Pro... more This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process Holfeld Diamat (EC register number RECYC076) which is based on the Diamat ® technology. The input of the process is washed and dried PET flakes originating from collected post-consumer PET containers, mainly bottles, containing no more than 5 % of PET from nonfood consumer applications. Through this process, post-consumer washed and dried PET flakes are mixed up to 50 % with virgin PET flakes before being heated in a crystallisation reactor (step 2) and extruded under vacuum into sheets (step 3). After having examined the challenge tests provided, the Panel concluded that the decontamination in the two consecutive extruders step 3 is the critical step for the decontamination efficiency of the process. The operating parameters to control its performance are well defined and are the temperature, the pressure and the residence time. The operating parameters of these steps in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.15 μg/kg food derived from the exposure scenario for toddlers. Therefore, the recycled PET obtained from the process Holfeld Diamat intended for the manufacture of recycled thermoformed trays and containers made with up to 50 % recycled post-consumer PET and intended for contact for long term storage at room temperature with all types of foodstuffs except packaged water is not considered of safety concern.
This paper provides an overview of the fundamental aspects pertaining an effective circular packa... more This paper provides an overview of the fundamental aspects pertaining an effective circular packaging. The main challenges of food packaging systems to comply with the principles of circular economy are addressed. A perspective of the technical issues that drive packaging developments is given, and the main barriers and limiting factors for packaging waste reduction, reusing, and recycling are discussed, particularly as applied to plastic packaging. The state-of-art of recycling plastics for food contact is presented, as well as the gaps for safety assurance. The relevance of consumer and the impact on the whole chain is discussed under the framework of citizens motivation, ability, and opportunity to engage the different measures. Finally, the main measures under the scope of the packaging and waste regulation, and foreseen amendments, and of the plastics recycling directive are briefly presented.
Smart Packaging Technologies for Fast Moving Consumer Goods, 2008
Traditional packaging has contributed greatly to the early development of food distribution syste... more Traditional packaging has contributed greatly to the early development of food distribution systems. However, it is no longer sufficient because today's society became increasingly complex. Innovative packaging with enhanced functions is constantly being sought in response to the consumer demands for minimally processed foods with fewer preservatives, increased regulatory requirements, market globalization, concern for food safety and the recent threat of food bioterrorism [1]. Active packaging (AP) and intelligent (smart) packaging (IP) are becoming increasingly popular among researchers and industry. Apparently there is no common, clear and unequivocal definition of these two types of system. The legislation [2] presents the following definitions: 'Active food contact materials and articles means materials and articles that are intended to extend the shelf-life or to maintain or improve the condition of packaged food; they are designed to deliberately incorporate components that would release or absorb substances into or from the packaged food or the environment surrounding the food'. 'Intelligent food contact materials and articles means materials and articles which monitor the condition of packaged food or the environment surrounding the food'. Active packaging is associated with the preservation and protection function and it refers to systems that are able to change the conditions the product is exposed to. Examples include oxygen absorbers, materials with permeability depending on temperature, antimicrobial materials, etc. Smart or intelligent packaging is associated with communication: a system capable of detecting, sensing, recording, tracing, communicating, and applying science logic, to facilitate
Strawberries purées are incorporated in foods and subjected to pH modulation according to the exp... more Strawberries purées are incorporated in foods and subjected to pH modulation according to the expected final food matrix. The effect of pH on strawberry polyphenols stored at 4 and 23°C for 90 days was evaluated. Total antioxidant activity and total phenolics content were only affected by time according to a first order model. The pH 4.5 induced higher decrease in (À)-epigallocatechin gallate (71% and 79%) and quercetin-3-glucoside (29% and 36%), for both storage temperatures. For pH 2.5 and 3.0, ellagic acid increased 84% for 4°C and 185% for 23°C. Anthocyanins concentration changes along storage were well described by first order model. The pH value of 2.5 presented the lower kinetic constant rate where cyanidin-3-glucoside, pelargonidin-3-glucoside and pelargonidin-3-rutinoside had a k = 0.04, 0.05 and 0.03 day À1. Lower storage temperature (4°C) and lower pH (2.5) were the best condition for the preservation of polyphenols in pasteurized strawberry during a 90-day storage period.
It is recognised that chemicals from packaging and other foodcontact materials can migrate into t... more It is recognised that chemicals from packaging and other foodcontact materials can migrate into the food itself and thus be ingested by the consumer. The monitoring of this migration has become an integral part of ensuring food safety. This article reviews the current knowledge on the food safety hazards associated with packaging materials together with the methodologies used in the assessment of consumer exposure to these hazards. Special attention is given to the most promising approaches for exposure assessment and to the technical and other barriers which need addressing.
The use of probabilistic approaches in exposure assessments of contaminants migrating from food p... more The use of probabilistic approaches in exposure assessments of contaminants migrating from food packages is of increasing interest but the lack of concentration or migration data is often referred as a limitation. Data accounting for the variability and uncertainty that can be expected in migration, for example, due to heterogeneity in the packaging system, variation of the temperature along the distribution chain, and different time of consumption of each individual package, are required for probabilistic analysis. The objective of this work was to characterize quantitatively the uncertainty and variability in estimates of migration. A Monte Carlo simulation was applied to a typical solution of the Fick's law with given variability in the input parameters. The analysis was performed based on experimental data of a model system (migration of Irgafos 168 from polyethylene into isooctane) and illustrates how important sources of variability and uncertainty can be identified in order to refine analyses. For long migration times and controlled conditions of temperature the affinity of the migrant to the food can be the major factor determining the variability in the migration values (more than 70% of variance). In situations where both the time of consumption and temperature can vary, these factors can be responsible, respectively, for more than 60% and 20% of the variance in the migration estimates. The approach presented can be used with databases from consumption surveys to yield a true probabilistic estimate of exposure.
ABSTRACT Respiratory behavior of fresh-cut ‘Rocha’ pear suggests that optimization of O2 concentr... more ABSTRACT Respiratory behavior of fresh-cut ‘Rocha’ pear suggests that optimization of O2 concentration inside modified atmosphere packages (MAP) is of limited benefit. To test this hypothesis, packages were designed to achieve three equilibrium O2 partial pressures. Fresh-cut ‘Rocha’ pear was treated with 250 mM calcium ascorbate solutions buffered at pH 3.0 and pH 7.0, packaged under the three MAP conditions, and stored at 5 °C for 20 d. Actual O2 levels (mean ± confidence interval at 95%) during the experiment were 16.7 ± 0.2, 1.8 ± 0.2 and 0.25 ± 0.04 kPa with corresponding CO2 levels of 1.3 ± 0.1, 4.3 ± 0.2 and 6.5 ± 0.4 kPa. Changes in quality attributes related to fruit metabolism, namely firmness, titratable acidity, pH, and soluble solids content were not affected by O2 levels. Overall changes in water activity, levels of ascorbate, and microbial growth were also independent of O2 levels. Oxygen partial pressure inside the packages affected browning, which was more intense at 16.7 kPa O2. Sensory analyses performed after 8 d in storage confirmed that panelists perceived the differences in color but did not detect differences in firmness or taste among the samples under different O2 levels. Browning was more intense at pH 3.0 than at pH 7.0 but the kinetics of other quality attributes were not affected by pH. No significant improvements of quality attributes dependent on the physiology of respiration of fresh-cut ‘Rocha’ pear can be obtained by reducing O2 partial pressure inside the packages.
The determination of the oxygen transmission rate (OTR) through closures in glass bottles is beco... more The determination of the oxygen transmission rate (OTR) through closures in glass bottles is becoming increasingly important for quality control of different batches and for development purposes. The Mocon method for measuring OTR is globally accepted and used in different applications. However, one of the major drawbacks this method presents when applied to bottle/closures systems is the long time required to obtain stable measurements when 40 mm long closures are tested. This paper describes a method to obtain OTR values with samples of reduced thickness with much shorter measurements time, since the condition of steady state during measurements is achieved faster and compares the estimated full-length commercial closure OTR with experimental values.
The mathematical modeling of migration of additives from plastics to food simulants was studied u... more The mathematical modeling of migration of additives from plastics to food simulants was studied using experimental data published in the literature, following two routes: the conventional approach using the solution of Fick's 2nd law, and a kinetic model based on the Weibull distribution function. The objective of this comparison was to permit using a mathematically simpler model equally able to describe migration data, and that could have a generally wider applicability by describing situations more complex than those that simple diffusional phenomena can describe. The relationship between the parameters of the two models was analyzed by regression of data generated by Fick's law using the Weibull model. The results show that the time constant parameter is related to the diffusion coefficient and the material thickness.
The goal of this research effort was to assess the efficacy of edible films produced from whey pr... more The goal of this research effort was to assess the efficacy of edible films produced from whey protein isolate (WPI) and glycerol, including incorporation of lactic acid (LA) and propionic acid (PRO), chitooligosaccharides with nominal MW of 3 kDa (COS) and natamycin (NA) as antimicrobial agents. Their features were evaluated in vitro via agar diffusion and viable cell counting, against spoilage microflora often found contaminating cheese surfaces. The effect of incorporating the aforementioned compounds upon thickness, moisture content (MC), solubility (S), density (ρ s), water activity (a w) and water vapor permeability (WVP), as well as upon tensile and optical properties of those films were also evaluated. Films formulated with LA, PRO or COS exhibited antimicrobial activity against all microorganisms tested, yet the viable cell count assay was more sensitive and reproducible. COS was the most active against Gram-negative bacteria, whereas LA was the most active against Gram-positive ones. NA was not active against bacteria, but displayed the strongest effect against yeasts. Incorporation of said antimicrobial compounds did not significantly (pN 0.05) affect film thickness, yet it significantly (p b 0.05) reduced tensile strength (TS). Incorporation of LA and NA in particular did not significantly (pb 0.05) affect MC, S, ρ s , WVP, elongation at break (EB) and Young's modulus (YM) values; however, a statistically significant increase (pb 0.05) of MC, S and WVP, together with a statistically significant decrease (p b 0.05) of ρ s were attained upon incorporation of PRO or COS. Moreover, PRO produced the highest variation (pb 0.05) in EB, TS and YM, whereas COS produced the highest change (pb 0.05) in optical properties.
The migration of chemicals from packaging materials into foods is an important issue in food safe... more The migration of chemicals from packaging materials into foods is an important issue in food safety and quality. European legislation sets specific migration limits which compliance must be assessed, surveyed and controlled by industry and authorities. Recently, the new Regulation UE 10/2011 included a new simulant-the Modified Polyphenylene Oxide (Tenax Ò) for solid dry foods. The objective of this work was to compare the migration kinetics of two antioxidants into Tenax Ò as compared to rice at 3 temperatures: 23, 40 and 70 C. The application of two different solutions of the 2nd Fick's law to describe and simulate the migration of the migrants to the present systems was studied. Diffusion coefficients ranged between 4.80E-13 and 2.84E-11 cm 2 /s for the migration into Tenax Ò and between 6.90E-18 and 4.33E-17 cm 2 /s for the migration into rice. The partition coefficients ranged between 6 and 29 for Tenax Ò and were over 1000 for rice. The activation energy for the migration into rice was half of that for Tenax Ò. The models described relatively well the experimental data (ε < 12% and < 30% for rice and Tenax Ò , respectively). Results indicate that the food simulant tends to overestimate migration values and thus can be safely used to assess materials compliance when materials are intended to contact with rice. However, results also indicate that Tenax Ò is a much more severe simulant in representing rice.
The migration of components from paper into Tenax Ò was studied to determine the influence of mol... more The migration of components from paper into Tenax Ò was studied to determine the influence of molecular size and chemical character of the migrant and the influence of paper characteristics in the migration process. The Weibull model was applied because Fick's 2nd law of diffusion gave poor fits in some cases. The migration pattern depended on the migrants molecular size and was independent of temperature in the studied range. The migration rate decreased with the migrant molecular size. The influence of the migrants character (polarity and vapour pressure) on the migration behaviour was also studied: nonpolar migrants with high vapour pressure presented low relative migration values and polar migrants presented high values of relative migration. Results indicated that the apparent partition coefficient between paper and the simulant Tenax Ò increased with the migrant vapour pressure and with both the paper grammage and the recycled pulp content.
and-conditions-of-access.pdf This article may be used for research, teaching and private study pu... more and-conditions-of-access.pdf This article may be used for research, teaching and private study purposes. Any substantial or systematic reproduction, redistribution , reselling , loan or sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material.
This paper presents an integrated approach to estimate exposure of Portuguese population to phtha... more This paper presents an integrated approach to estimate exposure of Portuguese population to phthalates as a contaminant originating from paperboard packaging. The approach combined data of migrant concentration in the foods resulting from a stochastic simulation, with consumption data of food packaged in paperboard. The results from the exposure model were validated with experimental values actually found in the food. A short surveillance exercise was conducted with samples collection from the market shelves to identify and quantify the phthalates present in the packages and in the food. The distribution of values for the di-butyl phthalate concentration in the packages was used as input of the initial concentration in the Weibull model to estimate the concentration of this phthalate in the foods. This distribution of occurrence data was then combined with the packaging usage data in a probabilistic simulation with the Monte Carlo sampling method. Exposure values ranged between 0 and 8.95 µg/day.Kg bw , a value close to the tolerable daily intake established by EFSA-10 µg/day.Kg bw. However, the 97.5 th percentile and the average were, respectively, 1.82 and 0.44 µg/day.Kg bw , indicating that further refinement of the estimates is not necessary. Other phthalates were also detected in the packaging samples: di-isobutyl phthalate and di-ethylhexyl phthalate. This latter was present in all packaging samples collected and was detected in a few food samples at values requiring further investigation.
Critical Reviews in Food Science and Nutrition, 2008
The migration of chemicals from food contact materials into foods is an important issue in food s... more The migration of chemicals from food contact materials into foods is an important issue in food safety. The assessment of materials compliance with regulations includes migration monitoring for many monomers and additives. However, it is recognized that predictive mathematical modelling can be used in many cases, to avoid or to reduce the effort on migration experiments. This article reviews the approaches followed to apply mathematical models to migration, particularly the models used, the approaches to estimate model parameters, and the systems used to experimentally validate the models. Conclusions on the issues requiring further research are drawn.
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