Cyclodextrins (CDs) are cyclic oligomers widely used in the food industry as food additives, for stabilization of flavours, for elimination of undesired tastes or other undesired compounds such as ...cholesterol and to avoid microbiological contaminations and browning reactions. In this review the characteristics of the most important CDs at industrial level (α-CD, β-CD and γ-CD) and their main properties from a technological point of view, such as solubility and their capability to form inclusion complexes are described. In addition, the present state-of-the-art on the use of these compounds in the food industry was reviewed.
Since their development in 1943, artificial neural networks were extended into applications in many fields. Last twenty years have brought their introduction into winery, where they were applied ...following four basic purposes: authenticity assurance systems, electronic sensory devices, production optimization methods, and artificial vision in image treatment tools, with successful and promising results. This work reviews the most significant approaches for neural networks in winemaking technologies with the aim of producing a clear and useful review document.
► Tool for the control of mancozeb, maneb and propineb in fruits and vegetables. ► DTCs were found in all the products analysed with the exception of strawberries. ► Peppers, tomatoes and lettuces ...were the commodity with more positive samples. ► EBDCs vs. PBDCs were the main contributors to the total fungicide load. ► Residues exceeding MRLs were identified in 6% of the samples.
Derivatisation, solid–liquid extraction, solid-phase purification and HPLC–DAD separation is a simple, fast, and accurate method developed for the determination of dithiocarbamate (DTC) fungicides in fruits and vegetables. Quantification is based on external standard calibration curves made with DTCs-spiked blank-matrices. Limits of detection (LODs) and limits of quantitation (LOQs) are in the range of 0.01–0.3 and 0.02–0.5mg/kg, respectively. Recoveries higher than 78% were obtained for the target DTCs in all the commodities studied. The aim of this research was to evaluate the quality and determine the concentrations of DTC fungicide residues in plant material harvested from September to November of 2010. Several fruits and vegetables produced in Spain were collected at small shops and large food chains distributed by the four provinces of Galicia (North-Western Spain). In total, 150 samples were studied (32 apples, 12 wine grapes, 32 lettuces, 32 peppers, 32 tomatoes, and 10 strawberries). Residues of DTCs were found in all the products analysed with the exception of strawberries, being ethylenebis(dithiocarbamates) (EBDCs) vs. propylenebis (dithiocarbamates) (PBDCs) the main contributors to the total pesticide load. Moreover, fungicide residues exceeding maximum residue limits (MRLs) were identified in 6% of the samples analysed, specifically on lettuces and peppers.
Only the intake of toxicologically-significant amounts can lead to adverse health effects even for a relatively toxic substance. In the case of residues in foods this is based on two major ...aspects-first, how to determine quantitatively the presence of a pollutant in individual foods and diets, including its fate during the processes within the food production chain; and second, how to determine the consumption patterns of the individual foods containing the relevant pollutants. The techniques used for the evaluation of the fate of pesticides during food processing have been critically reviewed in this paper to determine those areas where improvements are needed or desirable. Options for improvements are being suggested, including, for example, the development of a pan-European food composition database, activities to understand better effects of processing on individual food pesticides, and harmonization of food consumption survey methods with the option of a regular pan-European survey. The ultimate aim is to obtain appropriate estimations for the presence and quantity of a given chemical in a food and in the diet in general. Existing pragmatic approaches are a first crude step to model food pollutant intake. It is recommended to extend, refine, and validate this approach in the near future. This has to result in a cost-effective exposure-assessment system to be used for existing and potential categories of pollutants. This system of knowledge (with information on sensitivities, accuracy, etc.) will guide future data collection.
The binding constants of 14 different flavors (Maltol, Furaneol, Vanillin, Methyl Cinnamate, Cineole, Citral, Menthol, Geraniol, Camphor, Nootkatone, Eugenol, p-vinil Guayacol and Limonene) to ...cyclodextrins (α-cyclodextrin and β-cyclodextrin) have been determined by an UV–Vis spectrophotometric technique. In all cases the binding constant of flavors to β-cyclodextrin are bigger than the corresponding one to α-cyclodextrin. This fact is due to the different size of cyclodextrin cavity. As well as, a relationship between log
P of each flavor and the binding constants was found, proving that the driving force for host–guest complex formation is hydrophobic/hydrophilic interactions.
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•Tetraconazole promotes a significant decrease in the sugars-to-ethanol yield.•Methionol content decreased around 24% in the presence of Tetra Form.•The most significant increases ...were for fatty acids and ethyl esters (>23%).•Tetraconazole exerts effects on methionine and ergosterol biosynthesis pathways.•Coadyuvants of Tetra Form could have an essential impact on volatile biosynthesis.
The influence of antifungal tetraconazole residues (either as an active substance or as a commercial formulation product) on the fermentative activity of Saccharomyces cerevisiae yeast was evaluated in pasteurized Garnacha red must by using laboratory-scale fermentation assays. The presence of this fungicide promoted a slight decrease in glucose consumption. Volatile fermentative-derived compounds were evaluated in deep. Statistically significant changes were found in methionol (with a mean decrease of around 24%), fatty acids (with increments ranged from 23% to 66%), and ethyl esters (with increases ranged from 23% to 145%) contents when grape musts were enriched with the commercial formulation at both contamination levels assayed. Based on protein mass fingerprinting analysis, it was possible to relate these variations on volatiles content with changes in the activity of several enzymes (Met3p, Met14p, Adh2p, Hmg1p, Erg5p, Erg6p, Erg11p, and Erg20p) involved in the secondary metabolism of yeasts.
Mancozeb is a dithiocarbamate non-systemic agricultural fungicide with multi-site, protective action. It helps to control many fungal diseases in a wide range of field crops, fruits, nuts, ...vegetables, and ornamental plants. We have investigated the stability profiles of mancozeb in aqueous solutions to determine the effect of pH, temperature and light on the degradation process of mancozeb. In addition, the toxicological risk for humans associated with the joint intake of mancoze7b and its final degradation product, ethylenethiourea (ETU), was calculated and modelled as a function of the experimental conditions. Stability study results showed a very low stability profile of mancozeb in all the aqueous solutions with rapid degradation that varied with experimental conditions. The process followed first order kinetics. The study of the degradation kinetics showed a significant effect of pH*temperature interaction on the degradation process. The results also expressed that light has a greater impact on the stability of mancozeb and the formation of ETU. The current study concludes that mancozeb is unstable in aqueous solutions, particularly at an acid pH, in addition to presenting both severe light and lower temperature sensitivity. The toxicological risk associated with mancozeb degradation increases with time and temperature, being higher at basic pH and in absence of light.
•Mancozeb hydrolysis follows a first order reaction model.•Mancozeb hydrolysis is controlled by the pH*temperature interaction.•ETU and EBIS were the main hydrolysis products.•Mancozeb conversion to ETU is minimized at pH 2, 25°C in presence of light.•Risk associated with mancozeb degradation is higher at basic pH in absence of light.
The impact of mepanipyrim (Mep) and its corresponding commercial formulation (Mep Form) on Saccharomyces cerevisiae metabolites was assessed, separately, by using laboratory-scale wine fermentation ...assays on pasteurized red must. The presence of Mep did not alter the fermentation course. With regard to volatiles formed at the intracellular level by fermenting yeast cells, Mep residues affected mainly the acetate and ethyl ester biochemical pathways. In particular, the target acetates showed a notorious increment, >90%, in presence of commercial Mep Form at the higher dose assayed. The addition of Mep and Mep Form, at both tested levels, highly increased ethyl caprylate (between 42 and 63%) and ethyl caprate (between 36 and 60%) contents as the same as their respective fatty acid precursors. No important effects were observed on colour and non-volatile pyranoanthocyanins, probably due to the low anthocyanin content characteristic of pasteurized musts.
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•The presence of Mep did not alter the fermentation course.•Mep Form at 2MRL increased the acetate content >90%.•Ethyl caprylate and ethyl caprate were the more affected ethyl esters.
A quantitative, selective and sensitive HPLC method for the analysis of 14 fungicides in white grapes for vinification is described. The proposed method is based on liquid–liquid extraction (LLE) and ...solid-phase extraction (SPE) followed by liquid chromatography and diode array detection (HPLC–DAD). Dichloromethane–acetone (75:25, v/v) was the most appropriate solvent mix for extracting fungicides in white grapes. Silica cartridges resulted the most appropriate for extract purification purposes. Quality parameters of the proposed multiresidue method presented good recovery (ca. 85% for almost all target compounds) and precision (between 1.5 and 16%), and detection limits lower than maxima residual limits set by the 76/895/ECC and 90/642/ECC Directive. Five different white grapes for vinification produced in Rı́as Baixas area in Galicia (NW Spain) were analyzed in order to assess the performance of the method with real samples and to determine whether the concentration of the pesticides used exceed their maxima residue levels (MRLs). Results showed that grape concentrations for those identified fungicides were lower than those established by European legislation.
Mancozeb was spiked in smooth and curly lettuces at two different concentrations (low and high), and lettuces were subjected to different washing treatments (with tap water, Amukine, hydrogen ...peroxide, acetic acid, and ammonium hydroxide) at varying time and temperature. The determination of residual levels was then carried out by using acetonitrile extraction and high performance liquid chromatography with diode array detection (HPLC-DAD). The study of analysis of variance among these experiments allowed identifying the main factors governing the removal of mancozeb residues from lettuces. In general, the oxidant character of the washing agent is the most important condition that affects removal of mancozeb from lettuces, being hydrogen peroxide more efficient than sodium hypochlorite. Moreover, other factors controlling mancozeb removal from lettuces are surface wax, concentration gradient, and also washing pH. The washing processing factor resulted to be a rest of 4% under the optima conditions (either Amukine solution for 10 min at 25 °C, or hydrogen peroxide solution for 5 min at water temperature of 15 °C).
•The oxidant character of the washing agent is the most important condition.•Other factors are surface wax, concentration gradient, and also washing pH.•The washing processing factor resulted to be a rest of 4% at optima conditions.•For H2O2, there is not any big difference between its use at 15 or 25 °C.•For Amukine, the efficiency is about twice higher at 25 °C, the recommended temp.
