RESUMO
Polyglycerol polyricinoleate (PGPR) is a synthetic food additive containing a complex mixture of various esters. In recent years, there has been a growing trend to use PGPR-stabilized water-in-oil (W/O) emulsions to replace fat in order to produce low-calorie food products. In this respect, it is essential to comprehensively characterize the PGPR molecular species composition, which might enable to reduce its required amount in emulsions and foods based on a better understanding of the structure-activity relationship. This review presents the recent research progress on the characterization and quantitative analysis of PGPR. The influencing factors of the emulsifying ability of PGPR in W/O emulsions are further illustrated to provide new insights on the total or partial replacement of PGPR. Moreover, the latest progress on applications of PGPR in food products is described. Current studies have revealed the complex structure of PGPR. Besides, recent research has focused on the quantitative determination of the composition of PGPR and the quantification of the PGPR concentration in foods. However, research on the quantitative determination of the (poly)glycerol composition of PGPR and of the individual molecular species present in PGPR is still limited. Some natural water- or oil-soluble surfactants (e.g., proteins or lecithin) have been proven to enable the partial replacement of PGPR in W/O emulsions. Additionally, water-dispersible phytosterol particles and lecithin have been successfully used as a substitute of PGPR to create stable W/O emulsions.
Assuntos
Glicerol , Lecitinas , Glicerol/química , Ácidos Ricinoleicos/química , Emulsões/química , Água/químicaRESUMO
An improved fish smoking oven called FAO-Thiaroye Technique (FTT) has been introduced in Ghana and other countries in the Global South as a technical intervention for the high levels of polycyclic aromatic hydrocarbons (PAHs) in traditionally smoked fish produced in those regions. This study evaluated the extent to which the intervention reduces consumer exposure to PAHs (considering benzo(a)pyrene [BaP] as a marker) in smoked fish, using Ghana as a case. Smoked Sardinella sp. were sampled from two traditional ovens (Chorkor smoker and metal drum oven) and the FTT and their PAH levels were determined by gas chromatography-mass spectrometry. Samples of the product were also purchased from informal markets in three selected regions of Ghana and analyzed for their PAH levels. Cross-sectional consumer surveys were conducted in the selected regions to determine intakes of the commodity. A probabilistic risk assessment of PAH was then done by the margin of exposure (MoE) approach. BaP MoE as low as 1,060 and 752 were obtained for products from the traditional ovens and the informal markets, respectively, whereas the lowest value for FTT products was approximately 161,000. MoE values less than 10,000 were considered to denote a serious public health concern requiring risk management action. Therefore, the findings suggest that there is a potential health concern of high consumer exposure to PAHs in traditionally smoked fish in Ghana, and that the FTT is a technically viable intervention for the problem.
Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Animais , Estudos Transversais , Peixes , Contaminação de Alimentos/análise , Gana , Hidrocarbonetos Policíclicos Aromáticos/análise , Saúde Pública , Medição de Risco , Fumaça/análiseRESUMO
BACKGROUND: Smoked fish is a major source of animal protein in developing countries. It is largely produced by hot-smoking on traditional kilns using fuelwood. This practice is associated with high polycyclic aromatic hydrocarbon (PAH) contamination in products, with consequences for public health. An improved kiln, comprising the FAO-Thiaroye Technique (FTT), has been introduced by the Food and Agriculture Organization of the United Nations to address such a concern. The present study investigated the efficacy of the FTT in Ghana through comparative fish smoking experiments with traditional kilns followed by determination of PAH levels [benzo(a)pyrene (BaP) and PAH4] in the products by gas chromatography-mass spectrometry. For each kiln, the effect of smoking fuel type on PAH contamination was determined. The impact of the design characteristics of the FTT on the levels of the compounds was also determined. RESULTS: Mean BaP and PAH4 levels in the FTT products were up to 1.8 and 7.6 µg kg-1 , respectively, whereas the corresponding levels in traditional kiln products were up to 70 and 395 µg kg-1 . PAH levels in FTT products were below European Union regulatory limits, whereas levels in traditional kiln products exceed such limits by up to 33-fold. Across kiln types, the use of wood fuels caused higher PAH contamination compared to the use of fully-lit charcoal as an alternative fuel. CONCLUSION: The improved kiln (FTT) is efficacious in yielding smoked fish with a PAH content lower than the levels in traditional kiln products and also below current regulatory limits. Kiln design and type of processing fuel have significant impacts on PAH contamination during fish smoking. © 2019 Society of Chemical Industry.
Assuntos
Produtos Pesqueiros/análise , Contaminação de Alimentos/análise , Conservação de Alimentos/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Animais , Benzo(a)pireno/análise , Carvão Vegetal/efeitos adversos , Carvão Vegetal/análise , Contaminação de Alimentos/prevenção & controle , Conservação de Alimentos/instrumentação , Cromatografia Gasosa-Espectrometria de Massas , Gana , Madeira/efeitos adversos , Madeira/químicaRESUMO
BACKGROUND: Black soldier fly larvae are converters of organic waste into edible biomass, of which the composition may depend on the substrate. In this study, larvae were grown on four substrates: chicken feed, vegetable waste, biogas digestate, and restaurant waste. Samples of prepupae and substrates were freeze-dried and proximate, amino acid, fatty acid and mineral analyses were performed. RESULTS: Protein content of prepupae varied between 399 and 431 g kg-1 dry matter (DM) among treatments. Differences in amino acid profile of prepupae were small. On the other hand, the ether extract (EE) and ash contents differed substantially. Prepupae reared on digestate were low in EE and high in ash (218 and 197 g kg-1 DM, respectively) compared to those reared on vegetable waste (371 and 96 g kg-1 DM, respectively), chicken feed (336 and 100 g kg-1 DM, respectively) and restaurant waste (386 and 27 g kg-1 DM, respectively). Prepupal fatty acid profiles were characterised by high levels of C12:0 in all treatments. CONCLUSION: Since protein content and quality were high and comparable for prepupae reared on different substrates, black soldier fly could be an interesting protein source for animal feeds. However, differences in EE and ash content as a function of substrate should be considered. © 2016 Society of Chemical Industry.
Assuntos
Pupa/crescimento & desenvolvimento , Simuliidae/metabolismo , Resíduos/análise , Ração Animal/análise , Ração Animal/parasitologia , Animais , Galinhas , Esterco/parasitologia , Pupa/metabolismo , Simuliidae/crescimento & desenvolvimentoRESUMO
Infants less than 6 months of age receiving foods other than breast milk are at a high risk of exposure to mycotoxins. We surveyed food intake and estimated the risk of exposures to aflatoxin and fumonisin mycotoxins for infants less than 6 months of age in Northern Tanzania. A total of 143 infants were progressively recruited and three follow-up visits were made at 1, 3 and 5 months of age. A 24-h dietary recall technique was used to estimate flour intake of infants who had been introduced to maize foods. Aflatoxins and fumonisins in the flours were analysed using high-performance liquid chromatography technique. Exposure to aflatoxins or fumonisins was estimated using the deterministic approach. By the age of 3 months, 98 infants had started taking food; 67 of them, maize flours at levels ranging from 0.57 to 37.50 g per infant per day (average 8 g per infant per day). Fifty-eight per cent of 67 maize flour samples contained detectable aflatoxins (range 0.33-69.47 µg kg(-1) ; median 6 µg kg(-1) ) and 31% contained detectable fumonisins (range 48-1224 µg kg(-1) ; median 124 µg kg(-1) ). For infants who consumed contaminated flours, aflatoxin exposure ranged from 0.14 to 120 ng kg(-1) body weight (BW) per day (all above the health concern level of 0.017 ng kg(-1) BW per day as recommended by the European Food Safety Agency) and fumonisin exposure ranged from 0.005 to 0.88 µg kg(-1) BW per day. Insignificant association was observed between exposure to fumonisins or aflatoxins and stunting or underweight. Reducing aflatoxin and fumonisin contamination of maize and dietary diversification can prevent infants and the public, in general, from exposure to the toxins.
Assuntos
Aflatoxinas/administração & dosagem , Dieta , Contaminação de Alimentos/análise , Fumonisinas/administração & dosagem , Peso Corporal , Cromatografia Líquida de Alta Pressão , Farinha/microbiologia , Seguimentos , Análise de Alimentos , Microbiologia de Alimentos , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Fatores de Risco , Tanzânia , Zea mays/química , Zea mays/microbiologiaRESUMO
Se bioavailability in commercial pet foods has been shown to be highly variable. The aim of the present study was to identify dietary factors associated with in vitro accessibility of Se (Se Aiv) in pet foods. Se Aiv is defined as the percentage of Se from the diet that is potentially available for absorption after in vitro digestion. Sixty-two diets (dog, n 52; cat, n 10) were in vitro enzymatically digested: fifty-four of them were commercially available (kibble, n 20; pellet, n 8; canned, n 17; raw meat, n 6; steamed meat, n 3) and eight were unprocessed (kibble, n 4; canned, n 4) from the same batch as the corresponding processed diets. The present investigation examined if Se Aiv was affected by diet type, dietary protein, methionine, cysteine, lysine and Se content, DM, organic matter and crude protein (CP) digestibility. Se Aiv differed significantly among diet types (P< 0·001). Canned and steamed meat diets had a lower Se Aiv than pelleted and raw meat diets. Se Aiv correlated positively with CP digestibility in extruded diets (kibbles, n 19; r 0·540, P =0·017) and negatively in canned diets (n 16; r - 0·611, P =0·012). Moreover, the canning process (n 4) decreased Se Aiv (P =0·001), whereas extrusion (n 4) revealed no effect on Se Aiv (P =0·297). These differences in Se Aiv between diet types warrant quantification of diet type effects on in vivo Se bioavailability.
Assuntos
Ração Animal/análise , Dieta/veterinária , Selênio/farmacocinética , Fenômenos Fisiológicos da Nutrição Animal , Animais , Disponibilidade Biológica , Gatos , Proteínas Alimentares/metabolismo , Digestão , Cães , Manipulação de Alimentos/métodos , Alimentos em Conserva/análise , Carne , Selênio/análiseRESUMO
Chocolate confectionery fillings are generally regarded as microbiologically stable. The stability of these fillings is largely due to the general practice of adding either alcohol or preservatives. Consumer demands are now stimulating producers to move away from adding alcohol or other preservatives to their confectionery fillings and instead to search for innovative formulations. Such changes in composition can influence the shelf life of the product and may lead to spoilage by xerophilic fungi. The aim of this study was to test whether the production environment of Belgian chocolate confectionery factories and common ingredients of chocolate confectioneries could be potential sources of contamination with xerophilic fungal species. In the factory environment, the general and strictly xerophilic fungal spore load was determined using an RCS Air Sampler device in combination with DG18 and MY50G medium, respectively. Four basic ingredients of chocolate confectionery fillings were also examined for fungal spore levels using a direct plating technique. Detected fungi were identified to species level by a combination of morphological characterization and sequence analysis. Results indicated a general fungal spore load in the range of 50-250 colony forming units per cubic meter of air (CFU/m(3) air) and a more strict xerophilic spore load below 50 CFU/m(3) air. These results indicate rather low levels of fungal spores present in the factory environment. The most prevalent fungi in the factory environment were identified as Penicillium spp., particularly Penicillium brevicompactum. Examination of the basic ingredients of confectionery fillings revealed nuts to be the most likely potential source of direct contamination. In nuts, the most prevalent fungal species identified were Eurotium, particularly Eurotium repens.
Assuntos
Microbiologia do Ar , Cacau/microbiologia , Manipulação de Alimentos/instrumentação , Fungos/isolamento & purificação , Fungos/classificação , Fungos/genética , Esporos Fúngicos/classificação , Esporos Fúngicos/genética , Esporos Fúngicos/isolamento & purificaçãoRESUMO
A liquid chromatography triple quadrupole tandem mass spectrometry method was developed and validated to determine mycotoxins, produced by fungal isolates grown on malt extract agar (MEA). All twenty metabolites produced by different fungal species were extracted using acetonitrile/1% formic acid. The developed method was applied to assess the toxigenic potentiality of Aspergillus flavus (n = 11) and Aspergillus parasiticus (n = 6) strains isolated from black peppers (Piper nigrum L.) following their growth at 22, 30 and 37 °C. Highest mean radial colony growth rates were observed at 30 °C for A. flavus (5.21 ± 0.68 mm/day) and A. parasiticus (4.97 ± 0.33 mm/day). All of the A. flavus isolates produced aflatoxin B1 and O-methyl sterigmatocystin (OMST) while 91% produced aflatoxin B2 (AFB2) and 82% of them produced sterigmatocystin (STERIG) at 30 °C. Except one, all the A. parasiticus isolates produced all the four aflatoxins, STERIG and OMST at 30 °C. Remarkably high AFB1 was produced by some A. flavus isolates at 22 °C (max 16-40 mg/kg). Production of mycotoxins followed a different trend than that of growth rate of both species. Notable correlations were found between different secondary metabolites of both species; R(2) 0.87 between AFB1 and AFB2 production. Occurrence of OMST could be used as a predictor for AFB1 production.
Assuntos
Aspergillus flavus/isolamento & purificação , Aspergillus/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Micotoxinas/química , Piper nigrum/microbiologia , Espectrometria de Massas em Tandem/métodos , Aspergillus/química , Aspergillus/genética , Aspergillus/metabolismo , Aspergillus flavus/química , Aspergillus flavus/genética , Aspergillus flavus/metabolismo , Micotoxinas/metabolismoRESUMO
PGPR is an emulsifier (E476) widely used in the food industry. In this study, a gas chromatography-flame ionisation detection (GC-FID) method was developed for the quantitative characterisation of the polyglycerol composition of PGPR. The method was validated to analyse quantitatively the polyglycerol species in neat PGPR products and in PGPR samples present in a lipid matrix. This method consists of saponification, acidification and petroleum ether extraction to remove interfering fatty acids, neutralisation, silylation and finally GC-FID analysis. Phenyl ß-D-glucopyranoside was used as internal standard as sorbitol proved unsuitable due to its susceptibility to interference from Na/K chloride during silylation. The response factors of glycerol and diglycerol towards phenyl ß-D-glucopyranoside were determined using pure standards, while response factors of polyglycerols with a degree of polymerisation of at least 3 could be reliably estimated according to an effective carbon number (ECN) approach. The validity of the method applied to PGPR samples was further supported on the basis of a mass balance considering the experimentally determined polyglycerol and fatty acid content. Moreover, recoveries of di-, tri-, tetra- and pentaglycerol were more than 95% for various PGPR samples added to two different lipid matrices at 2 wt% and 5 wt% concentrations. Furthermore, the method proved to be very repeatable (with relative standard deviation values below 2.2%). On the other hand, the inevitable presence of glycerol in the lipid samples caused fouling of the detector and column overloading, requiring frequent cleaning of the detector and trimming off part of the column.
Assuntos
Glicerol , Lipídeos , Polímeros , Glicerol/análise , Glicerol/análogos & derivados , Polímeros/química , Cromatografia Gasosa , Lipídeos/análise , Lipídeos/química , Ácidos Ricinoleicos/análise , Ácidos Ricinoleicos/química , Ionização de ChamaRESUMO
Zamnè is a wild legume and a famine food that attracts interest for its health benefits and has become a delicacy in Burkina Faso. This study aimed to determine the nutritional quality of the traditionally cooked Zamnè, appreciate the effectiveness of the traditional cooking process, and compare the properties of the traditionally used cooking alkalis (i.e., potash or plant ash leachate and sodium bicarbonate). Yet, as shown, the traditional cooking of Zamnè is a very aggressive process that results in high disintegration of cell walls and membranes and leaching of most water-soluble constituents and nutrients (i.e., free amino acids, soluble nitrogen, sugars, soluble dietary fibers, and soluble phenolics). In addition, the extensive boiling and the cooking alkalis induced the sequestration of calcium, iron, magnesium, and zinc, significantly impairing their bioaccessibility. Despite the difference in the modus operandi of the cooking alkalis, there was no significant difference in the cooking outcomes. The traditionally cooked Zamnè presented high dietary protein (4.8 g), lipid (3.3 g), fiber (6.7-7.7 g), and metabolizable energy (63-65 kcal) contents (per 100 g fresh weight). Most antinutritional factors (i.e., non-protein nitrogen, tannins, and trypsin inhibitors) were eliminated. The proteins were relatively well preserved despite the aggressive alkaline processing. They demonstrated an appreciable digestibility (75%) and predicted PER (1.5) and a fairly balanced essential amino acid composition - which should completely meet the requirements for adults. The lipid content and composition were also well preserved and contained predominantly linoleic (C18:2n-6), oleic (C18:1c9), stearic (C18:0), and palmitic (C16:0) acids (33, 34, 10, and 15% total fatty acids, respectively). Overall, though extensive alkaline cooking seems a straightforward option to overcome the hard-to-cook problem of Zamnè, processing alternatives might be useful to reduce nutrient losses, improve the digestibility of the final product, and capture its full nutritional value.
Assuntos
Fabaceae , Fabaceae/química , Burkina Faso , Culinária , Valor Nutritivo , Verduras , Lipídeos , NitrogênioRESUMO
The non-thermal plasma (NTP) treatment of food products as an alternative for thermal processing has been investigated over the last few years. This quasi-neutral gas contains a wide variety of reactive oxygen and nitrogen species (RONS), which could be lethal for bacterial cells present in the product. However, apart from only targeting bacteria, the RONS will also interact with components present in the food matrix. Therefore, these food components will protect the microorganisms, and the NTP treatment efficiency will decrease. This effect was investigated by supplementing a plain agar medium with various representative food matrix components. After inoculation with Escherichia coli O157:H7 (STEC) MB3885, the plates were treated for 30 s by a multi-hollow surface dielectric barrier discharge (MSDBD) generated in either dry air or air at 75% humidity, at constant power (25.7 ± 1.7 W). Subsequently, the survival of the cells was quantified. It has been found that the addition of casein hydrolysate (7.1 ± 0.2 m%), starch (2.0 m%), or soybean oil (4.6 m%) decreased the inactivation effect significantly. Food products containing these biomolecules might therefore need a more severe NTP treatment. Additionally, with increasing humidity of the plasma input gas, ozone levels decreased, and the bactericidal effect was generally less pronounced.
RESUMO
Skim milk powder (SMP) as well as aqueous dispersions were subjected to dry and wet heat pre-treatment, respectively, to improve the heat stability of recombined filled evaporated milk (RFEM) derived therefrom. However, microrheological analysis revealed that prolonged incubation caused detrimental effects on the heat stability of RFEM, which were thought to be due to protein interactions. SDS-PAGE results indicated that protein aggregation via non-disulfide covalent bonds occurred upon long-time dry or wet heat incubation. This was probably related to some Maillard reaction products, which is sustained by the increase in lactulose and protein carbonyl content. Considerable protein aggregation via disulfide bonds in the serum was found upon wet heat incubation at temperatures of at least 80 °C. Principal component analysis (PCA) revealed that the negative effects of overprocessing on the heat stability of RFEM were predominantly related to protein cross-linking via non-disulfide covalent bonds related to protein carbonylation.
Assuntos
Temperatura Alta , Leite , Animais , Leite/química , Pós/análise , Agregados Proteicos , Carbonilação Proteica , Proteínas do Leite/químicaRESUMO
Coffee is a relevant source of dietary exposure for neoformed furan, alkyl furans and acrylamide. In this study, different statistical methods (hierarchical cluster analysis, correlation analysis, partial least squares regression analysis) were used for characterizing the formation of these process contaminants in green coffee beans roasted under the same standardized conditions. The results displayed a strong correlation between sucrose levels and furans in relation to the other sugars analyzed, while acrylamide formation was strongly related to the free asparagine. The data suggest that a sufficiently large amino acid pool in green coffee favors Maillard-induced acrylamide formation from asparagine, while reactions amongst the carbonyl-containing sugar fragmentation products leading to furan formation are suppressed. If the pool of free amino acids is small, it is depleted faster during roasting, thus favoring the formation of furans by caramelization, basically a sugar degradation process in which reactive carbonyl substances are generated and react together.
Assuntos
Coffea , Manipulação de Alimentos , Manipulação de Alimentos/métodos , Asparagina/química , Furanos/análise , Aminoácidos , Açúcares , Acrilamida/análise , Temperatura Alta , Coffea/químicaRESUMO
Drying is a common technique in the agrifood industry, but insufficient control in the drying process can result in changes to the fruit's appearance due to physiological damage during processing. The aim of this study was to investigate the impact of pretreatment and drying process parameters on Moroccan raisins' quality and safety. The experimental levels of pretreatment factors (blanching, browning agents) and drying temperature were defined at the beginning. Subsequently, a 24-factorial design was employed to provide a simple and reliable model capable of relating directly the response factor (drying time, color intensity change (E∗), chromaticity (C∗), and browning rate) to the variables (NaOH concentration, antibrowning agent concentration, temperature, and relative humidity). All four parameters had a statistically considerable effect on studied responses. Blanching for 5 minutes at 1% of NaOH solution, using an appropriate concentration of antibrowning agent (5% Na2S2O5), and drying at 70°C with 30% of relative moisture can lead to better preservation of grapes' appearance and quality (chromaticity (C∗) and color change (E∗)). Also, in these conditions, a lower browning rate (14.48%), a lower 5-hydroxymethylfurfural content (12.40 mg/100 g DW), and a higher level of polyphenols (135.79 ± 13.17 mg GAE/100 g DW) and flavonoid content (57.81 ± 3.08 mg Qeq/100 g DW) have been recorded while meeting international standards for SO2 content and microbial quality.
RESUMO
Crabs are an outstanding source of many essential nutrients. Little research has been performed on the nutritional quality of the red mangrove crab (Ucides occidentalis). In this research we investigated the proximate composition, fatty acid profile, amino acid composition, and mineral concentrations of red mangrove crabs sampled at two reserves within the Guayas estuary in Ecuador. Furthermore, we evaluated the influence of spatial variation. We found that the red mangrove is a good source of nutrition for a balanced diet and can contribute to the recommended intake of essential nutrients. Also, the red mangrove crab obtained better lipid nutritional quality indices compared to other shellfish species, apart from the EPA + DHA index values. Current research indicated that the final nutritional quality indices of the red crab were not influenced by harvest site. More research into the influence of environmental and ecological factors on the nutritional composition of crabs is suggested.
Assuntos
Braquiúros , Rhizophoraceae , Animais , Braquiúros/metabolismo , Estuários , Valor Nutritivo , Ácidos Graxos/metabolismo , Aminoácidos/metabolismo , LipídeosRESUMO
Nonthermal plasma is a mild processing technology for food preservation. Its impact on lipid oxidation was investigated in this study. Stripped methylesters were considered as a basic lipid model system and were treated by a multihollow surface dielectric barrier discharge. In dry air plasma, O3, ·NO2, ·NO3, and 1O2 were identified as the main reactive species reaching the sample surface. Treatment time was the most prominent parameter affecting lipid oxidation, followed by the (specific) power input and the plasma-sample distance. In humid air plasma, less O3 was detected, but ONOOH and O2NOOH were generated and presumed to play a role in lipid oxidation. Ozone mainly resulted in the formation of carbonyl substances via the trioxolane pathway, while reactive nitrogen species (i.e., ·NO2, ·NO3, ONOOH, and O2NOOH) led to the formation of hydroperoxides. The impact of short-living radicals (e.g., ·O, ·N, ·OH, and ·OOH) was restricted in general, since they dissipated too fast to reach the sample.·NO, HNO3, H2O2, and UV radiation did not induce lipid oxidation. All the reactive species identified in this study were associated with the presence of O2 in the input gas.
Assuntos
Peróxido de Hidrogênio , Dióxido de Nitrogênio , Metabolismo dos Lipídeos , Plasma , LipídeosRESUMO
Among all dietary proteins, dairy proteins are the most important source of bio-active peptides which can, however, be affected by modifications upon processing and storage. Since it is still unknown to which extent the biological activity of dairy proteins is altered by chemical reactions, this study focuses on the effect of photo-induced molecular changes on the angiotensin I converting enzyme (ACE) inhibitory activity. Milk proteins were dissolved in phosphate buffer containing riboflavin and stored under light at 4 °C for one month during which the molecular changes and the ACE-inhibitory activity were analysed. An increase in the total protein carbonyls and the N-formylkynurenine content was observed, besides a decrease in the free thiol, tryptophan, tyrosine and histidine content. These changes were more severe in caseins compared with whey proteins and resulted moreover in the aggregation of caseins. Due to these photo-induced molecular changes, a significant loss of the ACE-inhibitory activity was observed for casein peptides. A peptide analysis moreover illustrated that the decreased activity was not attributed to a reduced digestibility but to losses of specific ACE-inhibitory peptides. The observed molecular changes, more specifically the degradation of specific amino acids and the casein aggregation, could be assigned as the cause of the altered peptide pattern and as such of the loss in ACE-inhibitory activity.
Assuntos
Inibidores da Enzima Conversora de Angiotensina/química , Caseínas/química , Proteínas do Leite/química , Peptidil Dipeptidase A/química , Sequência de Aminoácidos , Aminoácidos/química , Cinurenina/análogos & derivados , Cinurenina/química , Oxidantes Fotoquímicos/química , Oxirredução , Fragmentos de Peptídeos/química , Processos Fotoquímicos , Carbonilação Proteica , Proteólise , Riboflavina/química , Análise de Sequência de Proteína , Compostos de Sulfidrila/química , Triptofano/química , Proteínas do Soro do LeiteRESUMO
Hazelnuts are widely used nowadays, and can pose a serious threat to allergic consumers due to cross-contamination that may occur during processing. This might lead to the presence of hidden hazelnut in foods. Therefore, reliable tests are needed to detect hazelnut, especially in processed foods. A hazelnut-specific indirect competitive ELISA based on polyclonal chicken antibodies was developed. The polyclonal antibodies were raised against modified hazelnut proteins in order to improve the detectability of hazelnut proteins in processed foods. The assay showed a detection limit of 1.36 microg hazelnut protein/mL of 5 mM urea in phosphate-buffered saline buffer (pH 7.4). Limited cross-reactivity with walnut and pecan nut was observed; no cross-reactivity was observed with other food ingredients. Blank cookies spiked before analysis showed recoveries of 73-107%. However, cookies spiked before baking showed that the detectability was severely decreased. Addition of lactose to the cookies, which led to more severe modification through the Maillard reaction, led to an increase in the detectability. These results indicate that using antibodies developed toward allergens modified through food processing-simulating reactions is a better approach for detection.
Assuntos
Corylus/química , Algoritmos , Animais , Anticorpos/análise , Anticorpos/isolamento & purificação , Soluções Tampão , Calibragem , Galinhas , Corylus/imunologia , Reações Cruzadas , Gema de Ovo/química , Gema de Ovo/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Análise de Alimentos/métodos , Manipulação de Alimentos , Hipersensibilidade Alimentar , Nozes/química , Proteínas de Plantas/análise , Reprodutibilidade dos TestesRESUMO
Feeding infants with maize can expose them to fumonisin mycotoxins. We assessed fumonisin exposure from complementary foods in rural Tanzania and determined strategies to reduce the exposure. We conducted a cross-sectional study in four villages of Tarakea division, Northern Tanzania. We used a repeat 24-hour dietary recall to collect data of maize consumption as complementary food for 254 infants aged 6-8 months. Fumonisin concentrations in the maize were also estimated. Fumonisin exposure was assessed using @risk analysis software. With the software, several maximum fumonisin contamination and maize consumption patterns were combined in order to determine effective strategies for minimizing fumonisin exposure. Of the infants, 89% consumed maize at amounts up to 158g/person/day (mean; 43g/person/day±28). The maize was contaminated with fumonisins at levels up to 3201µgkg(-1) . Risk of fumonisin intake above the provisional maximum tolerable daily limit of 2µgkg(-1) body weight was 15% (95% confidence interval; 10-19). The risk was minimized when the maximum contamination was set at 150µgkg(-1) . The risk was also minimized when the maximum consumption was set at 20g/child/day while keeping the maximum contamination at the European Union (EU) maximum tolerated limit (MTL) of 1000µgkg(-1) . Considering the economical and technological limitations of adopting good agricultural practices in rural Tanzania, it is practically difficult to reduce contamination in maize to 150µgkg(-1) . We suggest adoption of the EU MTL of 1000µgkg(-1) for fumonisins in maize and reduction, by replacement with another cereal, of the maize component in complementary foods to a maximum intake of 20g/child/day.
Assuntos
Contaminação de Alimentos/análise , Fumonisinas/efeitos adversos , Alimentos Infantis/efeitos adversos , Zea mays/química , Feminino , Contaminação de Alimentos/prevenção & controle , Fumonisinas/análise , Humanos , Lactente , Alimentos Infantis/análise , Masculino , Dose Máxima Tolerável , Saúde da População Rural , Tanzânia , DesmameRESUMO
This paper provides an estimation of the hazard related to the presence of furan and five alkyl furans (2- and 3-methylfuran, 2-ethylfuran, 2,5- and 2,3-dimethylfuran) in foodstuffs available in the Belgian market. To achieve this objective, a specific sampling plan was designed to ensure that the samples collected (n = 1003) represent the diversity of the Belgian food chain. Herein, the concepts of the Hazard Ratio of a sample (HRs) and the Hazard Index of a sample (HIs) were introduced to primarily characterize the hazard related to the co-occurrence of these compounds. The HRs was measured as the ratio of the potential daily exposure to a substance (expressed in mg/Kg of food) to both the 10% reference dose level for chronic effects (expressed in mg/(kg b.w*day)) and the human standard weight (expressed in kg). Whereas the HIs is the sum of the HRs of compounds that affect the same target organ/system, a hazard index greater than one indicates a highly contaminated matrix that could induce a hazard. It is an alarm indicating that additional attention should be given to this matrix. This may involve additional analyses to confirm the high level, to identify sources, etc. It is also an alarm for the risk assessor to be very careful with flagged matrices and to avoid combination with other matrices. The HIs highlight a relatively low concern for all foods analyzed (HI median < 1.0) with a relatively higher suspected hazard for coffee drinks (HI median = 0.068, HI max = 0.57). This preliminary estimation of the potential hazard suggests that coffee beverages should be examined in more detail in a full risk assessment and that coffee consumption should be taken with caution given the levels of furan and alkylfurans reported in this study.