Bioutilization of large-tonnage packaging material in the food industry (polyethylene)

Problems related to the biodeterioration processes of polyethylenes of various trademarks are considered in this work. Cultures of micromicetes from the main zonal soils of Russia are revealed, screening of microorganisms that degrade high-pressure polyethylene is performed, and the mechanism of biodeteriorations is suggested.     

Positively charged covalent organic framework and its application in the dispersive solid-phase extraction of ultraviolet-filters from food packaging material migrants

Abstract

Covalent organic frameworks (COFs) show excellent property, such as high porosity and excellent structure stability and were well applied in fields such as catalysis and adsorption, but most of the COFs showed similar structure and thus similar adsorption performance. Modification of simple COFs to enhance its adsorption performance in separation technique is an important issue. In this study, quaternary ammonium groups with long hydrophobic chain were introduced into a simple COF (TpPa-1) for the first time. The positively charged COF (PC-TpPa-1) can form electrostatic interaction and hydrophobic effect with negatively charged analytes, and showed good adsorption performance for ultraviolet-filters (UV filters). Under the optimum conditions, i.e. adsorbent amount 20?mg, pH?=?7, 1.0?mL acetonitrile as eluent, the obtained recoveries for all UV filters were in the range of 86.4–96.7%.The developed method was successfully applied to the determination of UV filters from food packaging material migrants with the aid of HPLC as a detector.     

Injector-internal thermal desorption from edible oils. Part 2: chromatographic optimization for the analysis of migrants from food packaging material

Injector-internal thermal desorption from edible oil or fat is a convenient sample preparation technique for the analysis of solutes in lipids or extracts from fatty foods. The injector temperature is selected to vaporize the solutes of interest while minimizing evaporation of the bulk material of the oil. This technique has been in routine use for pesticides for some time. Now its potential is explored for migrants from food contact materials, such as packaging, into simulant D (olive oil) or fatty/oily food, which means extending the range of application towards less volatile compounds. The performance for high boiling components was investigated for diisodecyl phthalate (DIDP) and diundecyl phthalate (DUP). Since the injector temperature needs to be as high as 260degreesC, some bulk material of the oil enters the column and must be removed after every analysis. This is achieved by a coated precolumn backflushed towards the end of each analysis. Desorption of the solutes is particularly efficient in the initial phase, when a thin sample film is spread on the liner wall, and is largely determined by the diffusion speed in the oil after the latter has contracted to droplets. An increased carrier gas flow rate during the splitless period supports the transfer into the column. It is concluded that the technique is attractive for migrant analysis, with DUP being at the upper limit of the boiling point.     

Contaminant migration from food packaging laminates used for heat and eat meals

EU legislation requires that components from food contact plastics should not migrate significantly into the food. The nature and extent of species migrating from laminated materials used for packaging 'heat and eat' meals have been investigated. Selected target analytes included additives incorporated into the polyolefin, e.g. the Irganox and Irgafos antioxidants, the diisocyanate and polyol residues from the adhesive and oligomeric material from the nylon. The results identified a wide range of migrants arising from each of the individual components of the laminate. Some of the migrants have been identified as precursors of the principal components of the laminate as well as those anticipated from a knowledge of the laminate construction. The levels of migration for those components identified and quantified has been well below the legal limits. Some significant migrant species have been however left unidentified by this investigation.     

Contaminant migration from food packaging laminates used for heat and eat meals

EU legislation requires that components from food contact plastics should not migrate significantly into the food. The nature and extent of species migrating from laminated materials used for packaging heat and eat meals have been investigated. Selected target analytes included additives incorporated into the polyolefin, e.g. the Irganox and Irgafos antioxidants, the diisocyanate and polyol residues from the adhesive and oligomeric material from the nylon. The results identified a wide range of migrants arising from each of the individual components of the laminate. Some of the migrants have been identified as precursors of the principal components of the laminate as well as those anticipated from a knowledge of the laminate construction. The levels of migration for those components identified and quantified has been well below the legal limits. Some significant migrant species have been however left unidentified by this investigation.     

The validation of a method for determining the migration of trace elements from food packaging materials into food

A new radiotracer method has been developed to measure the migration of trace elements from food contact packaging into four standard food simulants; acetic acid, ethanol, olive oil, deionised water. A sample of material is irradiated in a thermal neutron flux of 10¹⁶n·m^–2·s^–1 to activate the trace elements and produce a range of radionuclides. The sample is then placed in the food simulant and the migration of the radionuclides is monitored by performing -ray spectrometry on a sample of the simulant. Any radionuclides measured must be due entirely to the migration of the elements present in the plastic, since the simulant itself is not radioactive. Preliminary studies have shown that detection limits of around 0.2g·dm^–2 (0.002 mg/kg) can be achieved for antimony in a sample of polyethylene terephthalate. This method can now been extended to measure migration into real foods. This will highlight any differences between the standard simulants currently used and real foods. Since the method only involves irradiation of the packaging material, any food matrix can be studied.     

Application of radiometric method for element migration determination from plastic packaging to food

In the present study, a radiometric method was applied for element migration determination from food plastic packaging to simulating solutions and foodstuffs. This method consisted of irradiating plastics with neutrons, its exposure for migration and radioactivity measurements in the food or food-simulating solutions. The migration was studied for water, juice, soft drinks, acidic fatty food and dairy product plastic packages. The results indicated Co, Cr and Sb migration to the simulating solutions and food. However, the contamination of these elements in food from packaging material was lower than the maximum limit values established by the Brazilian Surveillance Agency (ANVISA) legislation.     

Oxygen indicators and intelligent inks for packaging food

The detection of oxygen using optical sensors is of increasing interest, especially in modified atmosphere food packaging (MAP), in which the package, usually containing food, is flushed with a gas, such as carbon dioxide or nitrogen. This tutorial review examines the ideal properties of an oxygen optical sensor for MAP and compares them with those developed to date, including the most recent advances. The basic technologies underpinning the different indicator types are described, examples given and their potential for application in MAP assessed. This tutorial review should be of interest to the MAP industry and researchers in optical sensors and oxygen sensing.     

Development of methods for testing barriers in food packaging materials

In some countries recycled materials are not allowed to come into contact with food without a protective layer such as plastic or virgin fiber. The purpose of this kind of barrier is to reduce migration of substances form beyond the barrier to the food. Two methods for studying a functional barrier are described. Both utilize migration cells in which one surface of the test specimen (for example a paper plate) is exposed to the food simulant. The first method involves the addition of indidcatsor substances to the non-food contact layer. The second method is to measure the migration of substances originally present in the layers beyond the functional barrier layer. Several kinds of barrier used in commercial papaer plates were studied and differences between them were found.     

Determination of bisphenol-type contaminants from food packaging materials in aqueous foods by solid-phase microextraction-high-performance liquid chromatography

A fast screening method consisting of off-line solid-phase microextraction coupled to HPLC and fluorescence detection, suitable for the analysis of several bisphenol derivatives and their degradation products in aqueous solution, has been developed. Detection limits of 0.7 ng ml(-1) for 2,2-bis[4-(glycidyloxy)phenyl]propane, 0.9 ng ml(-1) for bisphenol A bis(3-chloro-2-hydroxypropyl)ether, 1.1 ng ml(-1) for 2,2-bis(4-hydroxyphenyl)propane and 2.4 ng ml(-1) for bisphenol F diglycidyl ether have been achieved working in the linear range 10-500 ng ml(-1). The good analytical features achieved make the proposed method an interesting option for the direct determination of these compounds in aqueous canned food such as peas, tuna, olives, maize, artichokes or palm hearts. Both the optimization process and the results, including the analysis of real samples, are given and discussed.     

Applications of nanotechnology in food packaging and food safety: barrier materials, antimicrobials and sensors

In this article, several applications of nanomaterials in food packaging and food safety are reviewed, including: polymer/clay nanocomposites as high barrier packaging materials, silver nanoparticles as potent antimicrobial agents, and nanosensors and nanomaterial-based assays for the detection of food-relevant analytes (gasses, small organic molecules and food-borne pathogens). In addition to covering the technical aspects of these topics, the current commercial status and understanding of health implications of these technologies are also discussed. These applications were chosen because they do not involve direct addition of nanoparticles to consumed foods, and thus are more likely to be marketed to the public in the short term.     

MALDI-MS and colorimetric analysis of diisocyanate and polyol migrants from model polyurethane adhesives used in food packaging

The identification of the migrants, into food simulants, from a series of polyurethane adhesives used in the manufacture of plastic film laminates for use in common food packaging is described. Commercial materials, based on four different model adhesive systems, were prepared by an industrial collaborator. The MALDI-MS fingerprint patterns of the three polyether and one polyester polyol components of these adhesives were obtained for reference purposes. The decrease in the level of diisocyanate as a migrant versus time after lamination was confirmed by colorimetric measurements. The migration of the standard polyol samples through polyethylene pouches into water at 70 degrees C has been demonstrated and also the attenuation effect for different polyols. Cured laminates in the form of pouches were used to carry out the migration experiments into distilled water, inside the pouch, at 70 degrees C over a period of 2 h. Comparison of the migration results from the food packaging laminates with those from the polyethylene film confirmed the migration of unreacted polyol components for the polyether-based systems. Cyclic oligomers from the polyol starting materials were identified as the migrants from the polyester-based adhesive.     

Need for food reference material in Latin America

Summary Even if some Latin American countries still need to extend their capacity for food quality control, many do have good control laboratories and high quality research institutions. That makes the need for reference material in Latin America similar to that of other parts of the world.The region has special problems related to mail and shipment delays, and to the lack of information on available reference material. It is recommended that additional reference material being made available for vitamins in food, for polar and non-polar organophosphorus pesticides in vegetables, for organophosphorus pesticide and veterinary drugs in meat etc.Reference material should simulate real samples as closely as possible; reference samples for water should contain phthalates which in environmental samples interfere with organochlorines and reference material for organophosphates in vegetables should contain metabolites and degradation products.It is also recommended that commercial standards for trace metals should have the production date and the guaranteed stability printed on the label. Information on reference material should be included in the methods published by AOAC, AOCS and similar publications.