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Dioxins include polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and part of polychlorinated biphenyls (PCBs). Only the compounds that are chlorinated at the 2,3,7, and 8 positions have characteristic dioxin toxicity. PCDDs, PCDFs and PCBs accumulate in the food chain due to their high lipophilicity, high stability, and low vapor pressure. They are not metabolized easily; however their hydroxylated metabolites are detected in feces. They cause a wide range of endocrine disrupting effects in experimental animals, wildlife, and humans. Endocrine related effects of PCDDs, PCDFs and PCBs on thyroid hormones, neurodevelopment and reproductive development were referenced. In addition, some studies of contamination of foods, bioaccumulation, dietary exposure assessment, as well as challenges of scientific research in these compounds were reviewed. [ABSTRACT FROM AUTHOR]

Flavonoids are a large and diverse group of polyphenolic compounds with antioxidant effects. While the flavonoid content and composition profile clearly reflect the genetic background of the cultivar, environmental conditions and agronomic practices are also determinants for the composition of crops at harvest. Considerable research has been directed toward understanding the nature of polyphenols in different products and the factors influencing their accumulation. This review examines the flavonoids as a class of compounds, the role these compounds play in the plant, their contributions to product quality, and recent research on the impacts of environmental factors and cultural practices on flavonoid content in onions, highlighting how this knowledge may be used to modulate their polyphenolic composition at harvest or during post-harvest handling. [ABSTRACT FROM PUBLISHER]

Some polycyclic aromatic hydrocarbons (PAHs), particularly those with a high molecular mass, have been classified as probably being carcinogenic to humans by the International Agency for Research on Cancer (IARC). The significance of the determination of PAHs is reflected by the special attention the European Union is paying to regulating their maximum allowed levels in various types of foodstuffs. Like tobacco and smoked meats, alcoholic drinks can also contain these carcinogenic chemicals, as the latter have been detected in the charred insides of barrels, some ingredients such as caramel or the smoke released during the drying of germinated barley in beer or whisky. This paper determined the contents of seven PAHs in alcoholic beverages of variable alcoholic strength that had been aged in charred barrels for different times (months, years). The aim was to elucidate the dependence of the formation of seven PAHs on the type of charring (traditional or convective) used and the charring intensity (light, medium or heavy). Based on the results, the way the tree raw material is toasted strongly influences PAH levels in alcoholic drinks; thus, traditional charring produces increased amounts of PAHs from the wood relative to convective toasting. The sum of the analysed PAH concentrations in the aged alcoholic beverages studied ranged from zero for a white wine to 172  ng l –1 for a ‘brandy de jerez solera’. The carcinogenic indicator benzo[ a ]pyrene was found at concentrations below 10  ng l –1 . These PAH concentrations in alcoholic beverages are very low relative to those in smoked and char-broiled foodstuffs. Any health hazards, however, can be minimized by using convective toasting to manufacture the barrels where the drinks are to be aged. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs), at least those with high molecular mass, are classified as probable human carcinogens by the US Environmental Protection Agency. The importance of the material used to generate smoke is indicated by the attention that the European Union is paying to list the wood that can be used to produce smoking flavour agents. The paper examines the dependence on the nature of the wood used for smoking on the formation of eight PAHs (selected as markers of PAHs) and transfer of these PAHs into traditional Spanish smoked chorizo sausages with collagen and tripe casings. The results showed that the kind of combustion performed on different materials seriously affected the PAH levels in the smoke generated. Ignition and firing of the material with a flame compared with heating produced more PAHs in the smoke. The levels of PAHs found in the meat and in the collagen and tripe casings of the smoked chorizo samples suggest that the collagen-based casings behave as a better barrier to PAHs. [ABSTRACT FROM AUTHOR]

Methods of analysis for four additives (two antioxidants, IRGANOX 245 and 1035; an ultraviolet absorber, CHIMMASORB 81; and an optical brightening agent, UVITEX OB) in olive oil are reported. These additives have the potential to migrate from food-contact materials into the European Union fatty food simulant olive oil, which is the most difficult matrix for analysis. The additives were chosen because they differed in their chemically active groups, had different functions within the polymer, have low proposed specific migration limits and are commonly used in food-contact materials such as polystyrenes and polyolefins. The proposed analytical methods for the additives are simple, rapid, inexpensive and also broadly applicable to the aqueous food simulants. All methods were evaluated by constructing calibration curves, measurement of recovery and precision, and determining the limits of detection. Most of the methods involve direct injection of an olive oil solution for high-performance liquid chromatography analysis with ultraviolet-visible or fluorescence detection. The methods allowed establishment of additive stability and measurement of migration of the selected additives into olive oil at different time-temperature conditions used in migration studies into food simulants. [ABSTRACT FROM AUTHOR]

A simple, rapid, sensitive and inexpensive method has been developed for the determination of ethylenediamine (EDA) in European Union food simulants. The method involves precolumn derivatization with orthophthaldehyde (OPA) and 2-mercaptoethanol (ME) to obtain a fluorescent derivative. Liquid chromatographic (HPLC) elution was achieved with methanol-ultrapure water (65:35) as mobile phase with a Waters Spherisorb 5 μm ODS 2 column. Fluorescence detection (FD) was performed at 330 nm (excitation wave-length) and 450 nm (emission). Total chromatographic analysis time was <10 min. The proposed method was validated by checking linearity, detection and quantification limits, and precision. Relative recovery rates were of about 100% because samples and standard-spiked blanks were processed in the same way. Method precision (RSD <6%) was satisfactory and the quantification limit (0.25 mg l[SUP-1]) indicated that specific migration limit for EDA in EU food simulants (12 mg kg[SUP-1]) can be easily controlled. When the validated method was applied to epoxy-amine formulations used for can coatings under different curing conditions, EDA migration was <1.4 mg l[SUP-1]. [ABSTRACT FROM AUTHOR]

Different techniques and methods have been used to preserve foods. As long as scientific knowledge and technology have improved, new systems were discovered and applied in order to preserve foods. Pressurisation is a very recent technology in the food industry. It has been applied by this purpose since 1990. In this review after a brief historic description about high pressure technology; systems, methods and pressurisation equipment applied in foods are also described. Characteristics related to lethal effects and inactivation degree on pressurised microorganisms are extensively discussed and physic-chemist factors (temperature, pH, water activity and concentration of other compounds in food media) implied in high pressure treatments are also reviewed. Pressurisation is an excellent technique to sterilize foods and food ingredients, and it is already possible to get pressurised products in the food market. In general, it can be state that high pressure treatments help to maintain and improve the sensorial quality and foods preservation. © 2001 Altaga All rights reserved. Resumen Se han utilizado diferentes técnicas y métodos para la conservación de los alimentos. A medida que avanzaba el conocimiento científico y tecnológico, se han descubierto y aplicado nuevas formas para conservar los alimentos. La presurización es una técnica muy reciente en el campo alimentario, empleado desde 1990. En este trabajo, tras una breve descripción histórica de la tecnología de la alta presión; se describen también los sistemas, métodos y equipos generadores de alta presión empleados en la industria alimentaria. Se discuten de forma exhaustiva aspectos acerca de los efectos letales y del grado de inactivación que provoca la presurización sobre los microorganismos. Se revisan los factores físico-químicos más importantes (temperatura, pH, actividad del agua, concentración de solutos y composición del medio). La presurización es una buena técnica de esterilización de alimentos y es ya una realidad comercial. En líneas generales, se puede afirmar que la alta presión favorece y mejora la calidad sensorial y la conservación de los alimentos. © 2001 Altaga. Todos los derechos reservados. Palabras clave: Alta presión hidrostática, alimentos presurizados, inactivación de microorganismos Resumo Utilizáronse diferentes técnicas e métodos pra conservación dos alimentos. A medida que avanzaba o coñecemento científico e tecnolóxico, íbanse descubrindo e aplicando novas formas para conservar-los alimentos. A presurización é unha técnica moi novedosa no campo alimentario, empregada desde 1990. Neste traballo, tras uhna breve descripción histórica da tecnoloxía da alta presión, describense os sistemas, métodos e equipos xeneradores de alta presión empregados na industria alimentaria. Discutense de forma exhaustiva aspectos acerca dos efectos letales e do grado de inactivación que provoca a presurización sobre os microorganismos. Rrevisanzs os factores físico-químicos máis importantes (temperatura, pH, actividade da auga, concentración de solutos e composición do medio). A presurización é unha boa técnica de esterilización de alimentos e xa unha realidade comercial. En liñas xenais, podese afirmar que a alta presión favorece e mellora a calidade sensorial e a conservación dos alimentos. © 2001 Altaga. Todolos dereitos reservados. Palabras chave: Alta presión hidrostática, alimentos presurizados, inactivación de microorganismos [ABSTRACT FROM PUBLISHER]

El presente trabajo está principalmente enfocado en la evaluación de la migración de componentes de materiales de envasado al alimento, así como en los cambios en la calidad del alimento debidos a este fenómeno. Se realiza una revisión de la legislación europea sobre materiales para contacto alimentario, comparando esta legislación con otras fuera de la Unión Europea. La legislación europea está hoy en día centrada casi exclusivamente en materiales plásticos, dejando otros ampliamente utilizados como el papel y el cartón en situación de vacío legal. En este trabajo se resumen diferentes investigaciones realizadas para establecer una nueva normativa en el futuro para papel y cartón para contacto alimentario. Abstract The present work is mainly focused on the evaluation of the migration of components from food packaging materials into the packaged foodstuff and the changes in food quality caused by this phenomenon. A review about the European regulations dealing with food contact materials is carried out, comparing these regulations with others outside the European Union. The European regulations are nowadays focused mainly on plastic packaging, so other widespread used materials like paper and board have no regulations yet. A summary of the different investigations carried out in order to set new standards in the foreseeable future for food contact paper and board is also considered in this report. Resumo O presente traballo está principalmente dirixido á avaliación da migración de compoñentes de materiais do envase ó alimento, así como nos trocos na calidade do alimento debidos a este fenómeno. Realízase unha revisión da lexislacióu europea sobre materiais para contacto alimentario, comparando esta lexislación con outras fora da Unión Europea. A lexislación europea está hoxe en día centrada case en exclusiva nos materiais plásticos, deixando outros amplamente empregados como o papel e o cartón en situación de vacío legal. Neste traballo resúmense diferentes investigacións levadas a cabo para establecer unha normativa no futuro para papel e cartón para contacto alimentario. [ABSTRACT FROM PUBLISHER]