Risk ranking priority of carcinogenic and/or genotoxic environmental contaminants in food in Belgium.

This paper focuses on the risks of environmental carcinogenic and/or genotoxic contaminants in food. It describes, for each contaminant studied, the carcinogenicity and genotoxicity, the toxicological reference values, the exposure and the risk characterisation. The compounds studied were classified into 3 categories based on a risk assessment. Effects others than carcinogenicity and/or genotoxicity (e.g. endocrine disruption activity) were also taken into account for the classification. Given the low margin of exposure values for arsenic and lead, these two compounds are classified as priority 1 (high concern) for food safety and as a first priority to take actions to reduce exposure. Cadmium, methylmercury, dioxins and dioxin-like polychlorinated biphenyls (PCB), non-dioxin-like PCB and toxaphene are classified as priority 2 (medium concern). Polybrominated biphenyls, chlordane, heptachlor, dichlorodiphenyltrichloroethane (DDT) and metabolites, hexachlorobenzene, hexachlorocyclohexane (lindane included), polychlorophenols and their salts are classified as priority 3 (low concern).

Dietary cadmium intake by the Belgian adult population.

The aim of this study was to estimate the dietary cadmium (Cd) intake of the Belgian adult population, to compare this dietary Cd exposure to the tolerable weekly intake (TWI) recently established by the European Food Safety Authority (EFSA) and to determine the major food groups that contribute to dietary Cd exposure in Belgium. Food consumption data were derived from the 2004 Belgian food consumption survey (two 24 h recalls, 3083 participants). Cadmium concentrations in food items (n = 4000) were gathered from the control program of the Belgian Federal Agency for the Safety of the Food Chain for the period 2006-2008. Dietary intake per individual was calculated from consumption data and median Cd concentrations. The population mean, median and 95th percentile of the dietary intake values were 0.98, 0.85 and 2.02 µg kg⁻¹ body weight per week respectively. Two percent of the Belgian adult population has a dietary Cd intake above the recent TWI of 2.5 µg kg⁻¹ body weight established by EFSA in 2009. Cereal products and potatoes contribute for more than 60% to Cd intake.

Assessment of the acrylamide intake of the Belgian population and the effect of mitigation strategies.

The acrylamide (AA) intake of the Belgian consumer was calculated based on AA monitoring data of the Belgian Federal Agency for the Safety of the Food Chain (FASFC) and consumption data of the Belgian food consumption survey coordinated by the Scientific Institute for Public Health (3214 participants of 15 years or older). The average AA exposure, calculated probabilistically, was 0.4 microg kg(-1) body weight (bw) day(-1) (P97.5 = 1.6 microg kg(-1) bw day(-1)), the main contributors to the average intake being chips (23%), coffee (19%), biscuits (13%), and bread (12%). Additionally, the impact of a number of AA mitigation scenarios was evaluated (German minimization concept, scenarios for mitigation from the literature, signal values), which is an important issue for public health as well as for policy-makers. Specific actions in cooperation with the food industry to reduce the AA content of foods seems to be a more efficient strategy than mere implementation of signal values. Considering that an important share of the AA intake is due to prepared meals, the catering industry as well as consumers need to be better informed on the various possibilities for keeping the AA content of meals as low as possible.

Cadmium in the food chain near non-ferrous metal production sites.

Dietary cadmium (Cd) exposure was estimated for adults living in Cd-contaminated areas close to non-ferrous metal plants and compared with dietary Cd exposure in the general Belgian adult population. To evaluate the contamination levels of locally produced food items, 35 fruit samples, 97 vegetable samples, 98 samples of potatoes and 53 samples of meat, liver and kidney of cattle, which had resided for more than 18 months in the contaminated area, were analyzed for Cd. Mean Cd concentrations in fruit and vegetables were 1.1- to 9-fold higher than in samples from other regions at ambient Cd levels. Mean Cd concentrations in bovine meat, liver and kidney were 2-fold higher compared to samples from animals in other regions of Belgium. The estimated dietary intake was 31.3 and 63.3 microg day(-1) for average and large consumers, respectively, in the contaminated area, compared to 17 and 38.3 microg day(-1), respectively, for the general adult population. Excessive consumption of locally produced food items in areas close to non-ferrous metal plants could result in Cd intake levels exceeding the provisional tolerable weekly intake (PTWI).

On-farm contamination of animals with chemical contaminants.

Food products should not contain unsafe levels of chemical contaminants. However, it is not possible to monitor each and every one of the many thousands of chemicals that are used in our advanced societies. Chemical contaminants in foodstuffs of animal origin may be classified into three categories: natural contaminants (e.g. mycotoxins), environmental contaminants linked to industrialisation and/or urbanisation (e.g. dioxins and dioxin-like compounds) and authorised chemical products (e.g. residues of veterinary medical products). Chemical hazards may contaminate foodstuffs of animal origin all the way from farm to fork. Contamination may occur in any of the different production systems, and it is difficult to make comparisons between production systems (e.g. extensive versus intensive farming systems) with regard to food safety. Even when we take into account the latest analytical methods, which can detect ever-smaller quantities of residues, the relative importance of chemical contaminants seems to have declined during recent decades due to improvements in information and prevention. Nonetheless, individual incidents can never be ruled out and may have serious economic, health or social repercussions. Particular attention must be paid to chemical hazards, in order to reduce as much as possible the risks to livestock and to the consumer. Continued monitoring and periodic reassessment of risks posed by these contaminants (at the national level) are needed to detect or anticipate new problems, so that appropriate actions can be taken in the interest of public health. More attention should be paid to the production of detailed information, especially with regard to background data (e.g. the objectives of the monitoring, sampling methods, chemicals to be analysed, analytical methods, detection limits, raw data and specified units), in order to obtain a better basis for risk assessment. Such risk assessment provides control authorities with an effective tool for the exchange of information and measures to be taken to ensure food safety.

Protective influence of several packaging materials on light oxidation of milk.

Light-induced degradation reactions in milk create a serious problem for the dairy industry because of the development of off-flavors, the decrease in nutritional quality, and the severity and speed by which these phenomena develop. Packaging materials are essential to avoid this particular deterioration of milk. Therefore, efforts are being made to design protective polyethylene terephthalate (PET) packages. In the present study, a number of PET bottles were compared for their ability to avoid photo-oxidation in UHT semi-skimmed milk. The milk was packed in 3 types of PET bottles: one transparent bottle provided with an active oxygen-binding inner layer, one bottle with perfect light barrier, and one transparent bottle provided with a UV-absorbing additive. During 2 storage experiments, running parallel to each other for 2 mo, chemical milk quality parameters such as fat oxidation, vitamin and protein degradation, oxygen consumption, and color change were monitored. A trained taste panel compared the sensory quality of the illuminated milk stored in these bottles, with milk perfectly protected against light and oxygen. In the first study, milk was continuously illuminated at room temperature. A comparison was made for milk under storage conditions that simulated those expected during display in retail and supermarkets. The results of the 2 shelf-life studies showed that an adequate light barrier was apparently sufficient to avoid the light-induced oxidation of milk during extended storage. Oxygen barriers, on the other hand, did not provide a significant protection, nor did bottles with UV filter. If wavelengths detrimental to riboflavin were not completely excluded by the packaging material, incoming light could still give rise to photo degradation of milk. Accordingly, riboflavin and vitamin A were gradually degraded, milk fat was photo-oxidized, oxygen dissolved in the milk was consumed, and the sensorial quality decreased significantly.

Modeling of alpha-tocopherol loss and oxidation products formed during thermoxidation in triolein and tripalmitin mixtures.

The degradation of alpha-tocopherol and the formation of alpha-tocopherol and triacylglycerol oxidation products at high temperatures (150-250 degrees C) over a heating period (0-4 h) for a model system ranging between triolein and tripalmitin were modeled by use of an experimental design. The oxidation products of alpha-tocopherol formed under these conditions were alpha-tocopherolquinone (1 .4-7.7%) and epoxy-alpha-tocopherolquinones (4.3-34.8%). The results indicate a very high susceptibility of alpha-tocopherol to capture peroxyl radicals upon oxidation, leading to the formation of polar tocopherol oxidation products. Both alpha-tocopherolquinone and epoxy-alpha-tocopherolquinones were not stable upon prolonged heating and were further degraded to other unknown oxidation products. The kinetics of alpha-tocopherol oxidation were significantly influenced by the triolein/tripalmitin ratio. By increasing the level of triacylglycerol unsaturation the rate of alpha-tocopherol recovery after heating increased significantly from 2.2 to 44.2% whereas in the meantime triacylglycerol polymerization increased from 0 to 3.7%.

Gas chromatographic characterization of vegetable oil deodorization distillate.

Because of its complex nature, the analysis of deodorizer distillate is a challenging problem. Deodorizer distillate obtained from the deodorization process of vegetable oils consists of many components including free fatty acids, tocopherols, sterols, squalene and neutral oil. A gas chromatographic method for the analysis of deodorizer distillate without saponification of the sample is described. After a concise sample preparation including derivatization and silylation, distillate samples were injected on column at 60 degrees C followed by a gradual increase of the oven temperature towards 340 degrees C. The temperature profile of the oven was optimized in order to obtain a baseline separation of the different distillate components including free fatty acids, tocopherols, sterols, squalene and neutral oil. Good recoveries for delta-tocopherol, alpha-tocopherol, stigmasterol and cholesteryl palmitate of 97, 94.4, 95.6 and 92%, respectively were obtained. Repeatability of the described gas chromatographic method was evaluated by analyzing five replicates of a soybean distillate. Tocopherols and sterols had low relative standard deviations ranging between 1.67 and 2.25%. Squalene, mono- and diacylglycerides had higher relative standard deviations ranging between 3.33 and 4.12%. Several industrial deodorizer distillates obtained from chemical and physical refining of corn, canola, sunflower and soybean have been analyzed for their composition.

Identification of alpha-tocopherol oxidation products in triolein at elevated temperatures.

The effect of high-temperature treatment on the stability of alpha-tocopherol (1) in triolein was assessed under a reduced-pressure atmosphere (4-40 mbar) simulating the deodorization step of the refining of vegetable oils. A marked degradation of 1 was observed, which increased with increasing temperature (180-260 degrees C) and heating time (20-80 min). The degradation of 1 in triolein at 240 degrees C was inhibited by the addition of the synthetic antioxidant TBHQ or when heating was performed under nitrogen atmosphere, indicating oxidative degradation. The oxidation products were isolated and identified as alpha-tocopherolquinone (2), 4a,5-epoxy-alpha-tocopherolquinone (3), and 7,8-epoxy-alpha-tocopherolquinone (4).

Reduction of Bacillus subtilis, Bacillus stearothermophilus and Streptococcus faecalis in meat batters by temperature-high hydrostatic pressure pasteurization.

People have a growing preference for fresh, healthy, palatable and nutritious meals and drinks. However, as food deterioration is a constant threat along the entire food chain, food preservation remains as necessary now as in the past. High pressure processing is one of the emerging technologies being studied as an alternative to the classical pasteurization and sterilization treatments of food. Samples of fried minced pork meat were inoculated with strains of Streptococcus faecalis and with sporulating microorganisms like Bacillus subtilis and stearothermophilus. The samples were subjected to several combined temperature-high pressure treatments predicted by the mathematical model applied in Response Surface Methodology. Using the "Box-Behnken" concept, the number of tests for a whole area of pressure-temperature-time-combinations (pressure variation: 50-400 MPa, temperature variation 20-80°C, time variation 1-60 min) could be limited to 15. In the center point of the model, the experimental combination was performed in triple to estimate the experimental variance. All the tests were executed in a randomized order to exclude the disturbing effect of environmental factors. Microbial analysis revealed for each microorganism an important reduction in total plate count, demonstrating a superior pressure resistance of the sporulating microorganisms in comparison with the most pressure resistant vegetative species Streptococcus faecalis. The effect of the medium composition could be neglected, showing little protective effect of, e.g. the fat fraction as seen in heat preservation techniques.

Combined liquid and gas chromatographic characterisation of polyglycerol fatty acid esters.

In the present study a combined liquid and gas chromatographic technique is described for the analysis of polyglycerol fatty acid esters. Liquid chromatographic fractionation of samples resulted in pure standards of monoesters of di- and triglycerols and diesters of di- and triglycerols. Confirmation of their identity was achieved by LC-MS analysis. Moreover, a chromatographic identification of the mono- and diesters of cyclic diglycerol was proposed. From the isolation of pure esters and their gas chromatographic analysis, it was revealed that co-elution of several compounds occurred. Thus it was shown that prefractionation of the sample using a simplified liquid chromatographic separation, was necessary in order to characterise the esters correctly. In combination with some other chemical analyses, a complete profile of the chemical composition of polyglycerol fatty acid esters can be obtained.

Substituting enzymatically interesterified butter for native butter has no effect on lipemia or lipoproteinemia in Man.

The aim of this study was to determine whether substituting enzymatically interesterified butter for native butter in the usual diet affects lipid and lipoprotein levels in man. Parameters studied were serum total cholesterol, LDL-cholesterol, HDL-cholesterol, free cholesterol, phospholipids, triglycerides, apoA1 and apoB and the fatty acid composition of serum triglycerides, free fatty acids, phospholipids and cholesterol esters. Subjects were healthy volunteers and a controlled design was used. The only mathematically significant difference found when interesterified butter was substituted for butter was an about 7% lower fraction of oleic acid in the serum cholesterol esters (p = 0.005). In contrast to an earlier study where chemically interesterified butter fat was substituted for native butter, no indications are found in this study that replacing native butter by enzymatically interesterified butter, in amounts normally consumed, may have any beneficial effect on health.

Amino acid profiles after sprouting, autoclaving, and lactic acid fermentation of finger millet (Eleusine coracan) and kidney beans (Phaseolus vulgaris L.).

Seeds of finger millet (Eleucine coracan (L.) Gaertner) and kidney beans (Phaseolus vulgaris L.) were sprouted, autoclaved, and fermented during the processing of a weaning (complementary) food for children. Relative changes in individual amino acids with processing were evaluated. Finger millet and kidney beans both showed a good percentage of essential to total amino acids, with 44. 2-44.9% in finger millet and 44.2-45.1% in kidney beans, when compared to 33.9% for the FAO/WHO reference protein for 2-5 year old children. Sprouting resulted in a significant decrease in lysine in kidney beans. Autoclaving caused significant decreases in histidine, while fermentation significantly decreased phenylalanine and increased tryptophan in finger millet. The leucine-to-lysine ratio, which is an indicator of the pellagragenic character of a protein, was significantly improved in finger millet by both sprouting and fermentation.

Effect of irradiation, packaging, and postirradiation cooking on the thiamin content of chicken meat.

The effect of irradiation with X rays or electrons, irradiation and storage temperature, and postirradiation cooking on the thiamin content of vacuum- or air-packaged minced chicken meat was examined. Samples irradiated with 3-kGy X rays (50 Gy/min) or electrons (5 kGy/min) contained less thiamin than the control specimens, but no differences between both irradiation methods were detected. The thiamin content in samples stored and/or irradiated at 5 degrees C was between 13 and 24 microg per 100-g product lower than in samples stored and/or ionized at -18 degrees C. The same difference in thiamin content was found for specimens packaged in a vacuum or air package, respectively. Vacuum packaging lead to a greater loss of drip than air-packaged samples. The biggest loss of thiamin, 31.1 and 28.0% for X rays and electron beams, respectively, was measured for vacuum-packaged specimens stored and irradiated at 5 degrees C. Compared with the cooked minced chicken breast meat, a higher thiamin content (6 to 17 microg of thiamin per 100-g product) was obtained for the raw samples. When irradiation and vacuum packaging were compared as two separate preservation techniques, the two methods had approximately the same effect on the thiamin content of the minced chicken meat. The mean temperature of the samples after cooking was 87.2 +/- 4.9 degrees C. However, significant differences in internal temperature after cooking of the samples were measured between air- and vacuum-packaged samples.