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The characterization and quantification of phenolic compounds in bearberry leaves were performed using hyphenated ion mobility spectroscopy (IMS) and a quadrupole time-of-flight mass spectrometer. A higher identification confidence level was obtained by comparing the measured collision cross section (TWCCSN2) with predicted values using a machine learning algorithm. A total of 88 compounds were identified, including 14 arbutin derivatives, 33 hydrolyzable tannins, 6 flavanols, 26 flavonols, 9 saccharide derivatives, and glycosidic compounds. Those most reliably reproduced in all samples were quantified against respective standards. Arbutin (47-107 mg/g), 1,2,3,4,6-pentagalloylglucose (6.6-12.9 mg/g), and quercetin 3-galactoside/quercetin 3-glucoside (2.7-5.7 mg/g) were the most abundant phenolic components in the leaves. Quinic acid and ellagic acid were also detected at relatively high concentrations. The antioxidant activity of the most abundant compounds was evaluated. A critical view of the advantages and limitations of traveling wave IMS and CCS for the discovery of natural products is given.

Toward a more rigorous inspection of food contact materials, the importance of sample preparation for nontarget screening should be addressed. Direct immersion-solid-phase microextraction coupled to gas chromatography mass spectrometry (DI-SPME-GC-MS) was optimized for nontarget screening of migrants in 3% acetic acid, 10% ethanol, and 95% ethanol food simulants by response surface methodology (RSM) in the present study. Optimum conditions were DVB/CAR/PDMS fiber, no pH adjustment for 10% and 95% ethanol simulant but pH adjustment to 7 for 3% acetic acid simulant, no salt addition, 5 min preincubation, 55 min extraction at 70 °C, and 8 min desorption at 250 °C. In addition, 9.5 times dilution of 95% ethanol samples prior to extraction was required. pH modification of 3% acetic acid samples was found to be critical for the extraction of amines. The proposed methodology was then evaluated by determining the limit of detection (LOD) as well as repeatability of 35 food contact materials-related substances. Except for those amines and diols which have a relatively high LOD, the LODs of the rest of the substances were 0.1-14.1 μg/kg with a precision of 1.9-23.0% in 10% ethanol and were 0.1-20.2 μg/kg with a precision of 2.5-19.6% in 3% acetic acid simulant. The LOD and precision in 95% ethanol simulant were 0.7-163.7 μg/kg and 1.4-26.8%, respectively. The proposed method can be applied for an overall screening of migrants from these three simulants at even trace levels, though attention should be paid to some specific analytes, e.g., diols and amines, which could have a high LOD and toxicity.

The oxygen radical absorbance capacity (ORAC) method was used to characterize the antioxidant capacity of natural extracts of green tea, green coffee, and grapefruit. These natural extracts were incorporated into a plastic film layer, which was subsequently subjected to a free radical gas stream in order to determine the antioxidant capacity directly in the active film. The green tea extract (GTE) afforded the strongest antioxidant activity. To identify the active compounds in the extract, concentration of the diverse catechins in samples were determined by HPLC-UV analysis. The results showed that the content of catechins in the GTE is around 77% (w/w), the major components being (-)-epigallocatechin gallate, (-)-epicatechin gallate, and (-)-epicatechin. A variation in the concentration profile of catechins was detected during the oxidation process. The chromatographic study demonstrated that (-)-gallocatechin, (-)- epigallocatechin, (+)-catechin, and (-)-catechin gallate exhibited the most radical scavenging.

Active packaging is an emerging food technology to improve the quality and safety of food products. Many works have been developed to study the antimicrobial activity of essential oils. Essential oils have been traditionally used as flavorings in food, so they have an important odor impact but they have as well antimicrobial properties that could be used to protect the food. Recent developments in antimicrobial active packaging showed the efficiency of essential oils versus bread and bakery products among other applications. However, one of the main problems to face is the odor and taste they could provide to the packaged food. Using some aromas to mask the odor could be a good approach. That is why the main objective of this paper is to develop an antimicrobial packaging material based on the combination of the most active compounds of essential oils (hydrocinnamaldehyde, oregano essential oil, cinnamaldehyde, thymol, and carvacrol) together with some aromas commonly used in the food industry. A study of the concentration required to get the antimicrobial properties, the organoleptic compatibility with typical aroma present in many food systems (vanilla, banana, and strawberry), and the right combination of both systems has been carried out. Antimicrobial tests of both the mentioned aromas, the main components of some essential oils, and the combination of both groups were carried out against bacteria (Enterococcus faecalis, Listeria monocytogenes, Bacillus cereus, Staphylococcus aureus, Salmonella choleraesuis, Yersinia enterocolitica, Escherichia coli), yeasts (Candida albicans, Debaryomyces hansenii, Zygosaccharomyces rouxii), and molds (Botrytis cinerae, Aspergillus flavus, Penicillium roqueforti, Eurotium repens, Penicillium islandicum, Penicillium commune, Penicillium nalgiovensis). The sensory properties of the combinations were evaluated with a triangular test and classification was by an order test; the odor threshold of the aroma compounds was also studied. The results reveal that none of the aromas had antimicrobial properties. The most antimicrobial compounds are thymol, carvacrol, and cinnamaldehyde, but none of them could be combined with banana aroma, whereas only thymol with strawberry aroma gave the right combined organoleptic profile. All of the antimicrobials under study could be combined with vanilla aroma, providing both antimicrobial property and the odor expected.

A new active paper package based on the incorporation of cinnamon essential oil to solid wax paraffin as an active coating is proposed, developed, and evaluated. The antifungal activity of the active paper is tested against Rhizopusstolonifer, and the results demonstrate that 6% (w/w) of the essential oil in the active coating formulation completely inhibits the growth of R. stolonifer, whereas 4% still has strong antimicrobial activity in in vitro conditions. Then, active paper is evaluated with actual food, sliced bread, using different storage times. After 3 days of storage, almost complete inhibition is obtained with 6% cinnamon essential oil. Qualitative analysis by solid-phase microextraction and determination of cinnamaldehyde in the sliced bread were also performed and confirmed the strong correspondence between the inhibition of the mold and the amount of cinnamaldehyde in the bread.

The antimicrobial activity in the vapor-phase of laboratory-made flexible films of polypropylene (PP) and polyethylene/ethylene vinyl alcohol copolymer (PE/EVOH) incorporating essential oil of cinnamon ( Cinnamomum zeylanicum), oregano ( Origanum vulgare), clove ( Syzygium aromaticum), or cinnamon fortified with cinnamaldehyde was evaluated against a wide range of microorganisms: the Gram-negative bacteria Escherichia coli, Yersinia enterocolitica, Pseudomonas aeruginosa, and Salmonella choleraesuis; the Gram-positive bacteria Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, and Enterococcus faecalis; the molds Penicillium islandicum, Penicillium roqueforti, Penicillium nalgiovense, Eurotium repens, and A spergillus flavus and the yeasts Candida albicans, Debaryomyces hansenii, and Zigosaccharomyces rouxii. Films with a nominal concentration of 4% (w/w) of fortified cinnamon or oregano essential oil completely inhibited the growth of the fungi; higher concentrations were required to inhibit the Gram-positive bacteria (8 and 10%, respectively), and higher concentrations still were necessary to inhibit the Gram-negative bacteria. PP films were more effective than PE/EVOH films. The atmospheres generated by the antimicrobial films inside Petri dishes were quantitatively analyzed using headspace-single drop microextraction (HS-SDME) in combination with gas chromatography-mass spectrometry (GC-MS). The analyses showed that the oregano-fortified PP films released higher levels of carvacrol and thymol, and the cinnamon-fortified PP films released higher levels of cinnamaldehyde, during the first 3-6 h of incubation, than the corresponding PE/EVOH films. Shelf-life tests were also performed, demonstrating that the antifungal activities of the films persisted for more than two months after their manufacture. In addition, migration tests (overall and specific) were performed, using both aqueous and fatty simulants, to ensure that the films meet EU regulations regarding food contact materials. Following contact with the tested films, the substances that had migrated into the aqueous simulants were recovered by direct immersion-single drop extraction (DI-SDME) and then analyzed by GC-MS. The fatty stimulant (isooctane) was directly injected into the chromatographic system.

The aim of the study presented here was to gain knowledge about the vapor-phase antimicrobial activity of selected essential oils and their major putatively active constituents against a range of foodborne bacterial and fungal strains. In a first step, the vapor-phase antimicrobial activities of three commercially available essential oils (EOs)-cinnamon (Cinnamomum zeylanicum), thyme (Thymus vulgaris), and oregano (Origanum vulgare)-were evaluated against a wide range of microorganisms, including Gram-negative bacteria (Escherichia coli, Yersinia enterocolitica, Pseudomonas aeruginosa, and Salmonella choleraesuis), Gram-positive bacteria (Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, and Enterococcus faecalis), molds (Penicillium islandicum and Aspergillus flavus), and a yeast (Candida albicans). The minimum inhibitory concentrations (MICs) were generally lower for oregano EO than for the thyme and cinnamon EOs, especially against the relatively resistant Gram-negative. The persistence of the EOs' antimicrobial activities over time was assessed, and changes in the composition of the atmosphere they generated over time were determined using single-drop microextraction (SDME) in combination with gas chromatography-mass spectrometry (GC-MS) and subsequent analysis of the data by principal component analysis (PCA). More relevant chemicals were selected. In addition, the vapor-phase activities of putatively key constituents of the oils were screened against representative Gram-positive (L. monocytogenes) and Gram-negative (S. choleraesuis) bacteria, a mold (A. flavus), and a yeast (C. albicans). Of the tested compounds, cinnamaldehyde, thymol, and carvacrol showed the strongest antimicrobial effectiveness, so their MICs, defined as the minimum vapor concentrations that completely inhibited detectable growth of the microorganisms, were calculated. To check for possible interactions between components present in the EOs, cinnamon EO was fortified with cinnamaldehyde and thyme EO with thymol, and then the antimicrobial activities of the fortified oils were compared to those of the respective unfortified EOs using fractional inhibitory concentration (FIC) indices and by plotting inhibition curves as functions of the vapor-phase concentrations. Synergistic effects were detected for cinnamaldehyde on A. flavus and for thymol on L. monocytogenes, S. choleraesuis, and A. flavus. In all other cases the fortification had additive effects, except for cinnamaldehyde's activity against S. choleraesuis, for which the effect was antagonistic. Finally, various microorganisms were found to cause slight changes over time to the atmospheres generated by all of the EOs (fortified and unfortified) except the fortified cinnamon EO.

A new antioxidant active packaging material for food has been designed and developed, consisting of a polypropylene film in which some natural antioxidants have been immobilized. The antioxidant properties of the new material have been tested by using both pure myoglobin and fresh beef steaks. Two different cell configurations (glass vial and Petri dish) and four different myoglobin concentrations-according to the common content of this compound in fresh meat and meat derivatives (1080, 1995, 3332, and 4414 microg g(-1), respectively)-have been evaluated in oxidation studies. Furthermore, three different concentrations of natural antioxidants in the film (designated as PR1, PR2, and PR3) were evaluated. Once myoglobin samples and the active films were introduced in the cell, they were exposed to cool white fluorescent light to accelerate oxidation for a period of time ranging from 5 to 30 days. Remaining myoglobin concentration was measured by molecular absorption UV-vis spectrophotometry at 409 nm. Organoleptic properties and color, texture, and physical characteristics of fresh meat packaged with the new active film have also been measured to evaluate the shelf life of the packaged meat. Results showed that, compared to normal polypropylene, the active film containing natural antioxidants efficiently enhanced the stability of both myoglobin and fresh meat against oxidation processes, thus being a promising way to extend the shelf life of fresh meat.

The antimicrobial activity of essential oils (EOs) of cinnamon (Cinnamon zeylanicum), clove (Syzygium aromaticum), basil (Ocimum basillicum), rosemary (Rosmarinus officinalis), dill (Anethum graveolens), and ginger (Zingiber officinalis) was evaluated over a range of concentrations in two types of contact tests (solid and vapor diffusion). The EOs were tested against an array of four Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus, Enterococcus faecalis, and Listeria monocytogenes), four Gram-negative bacteria (Escherichia coli, Yersinia enterocolitica, Salmonella choleraesuis, and Pseudomonas aeruginosa), and three fungi (a yeast, Candida albicans, and two molds, Penicillium islandicum and Aspergillus flavus). The rationale for this work was to test the possibility of creating a protective atmosphere by using natural compounds that could extend the shelf life of packaged foodstuffs while minimizing organoleptic alterations. In the solid diffusion tests, cinnamon and clove gave the strongest (and very similar) inhibition, followed by basil and rosemary, with dill and ginger giving the weakest inhibition. The fungi were the most sensitive microorganisms, followed by the Gram-positive bacterial strains. The Gram-negative strain P. aeruginosa was the least inhibited. The composition of the atmosphere generated by the EOs, and their minimum inhibitory concentrations (MICs), were determined using a disk volatilization method, in which no inhibition from rosemary or basil was observed. Cinnamon and clove, once again, gave similar results for every microorganism. As a general rule, MIC (fungi)MIC (bacteria) with no clear differences between Gram-positive or -negative strains except for P. aeruginosa, which was not inhibited by any of the EOs in the vapor phase. The atmosphere generated from the EOs was analyzed by means of solid-phase microextraction combined with gas chromatography-ion trap mass spectrometry. Differences among the volatiles in the EOs, which may be responsible for the differences in their antimicrobial performances, were found.

Both specific and overall migration tests have been applied to new experimental food packaging-active plastic films with antioxidant properties, including in its composition a natural rosemary extract. Determination of volatile and semivolatile compounds migrating from plastic to the four established simulants showed that both specific and overall migration was very low. The results obtained gave values 20 times lower than the established limits in the worst case. So, from the point of view of health risk, the new active packaging can be considered as safe. Analytical procedure used provided the necessary information about the migration behavior, with good analytical characteristics and detection limits in the sub μg kg-1 range. Besides, no significant difference was found between laboratory and factory-made samples, which is an important issue for industrial production, the next step in the development of the new antioxidant active film. Keywords: Active packaging; migration; antioxidant; rosemary; polyp...

The behavior of two synthetic adsorbents, Tenax and Porapak, as food simulants in contact with some plastic containers commercially available, recommended to be used for heating food in microwave ovens, has been studied. Containers of polycarbonate (PC), polypropylene (PP), polypropylene random (PP-random), polypropylene−20% talcum (PP%T), and the copolymer styrene−acrylonytrile (SAN) have been studied at 150 °C (PC) and 120 °C (the others). The volatile compounds released from the plastics and trapped into Tenax and Porapak have been analyzed by thermal desorption−gas chromatography−mass spectrometry (TD-GC-MS). The results obtained from these migration studies at high temperature are shown and discussed. Tenax performs better than Porapak at low temperature since the former desorbs the compounds at high temperature. Keywords: Migration; solid simulants; food analysis; volatile compounds; packaging.

The optimization of supercritical fluid extraction using CO2 for the extraction of contaminants in 15 samples of recycled paper and board (P&B) has been studied. An experimental design was used for simultaneous optimization of the variables involved in both the extraction step and the collection of the extract. Methanol was used as modifier. Several plastisizers such as diethyl phthalate, diisobutyl phthalate, di-n-butyl phthalate, dioctyl adipate, and diethylhexyl phthalate (from 2 to 100 microg/g of paper) were found in the recycled P&B samples. A discriminate analysis applied to all results obtained allow us to classify the samples in three different groups according to the content of recycled pulp (0, 10-30, and > 80% of recycled pulp), the sample thickness (from 600 microm), and the surface treatment of the paper. The analytical behavior and the results are discussed.

The main objective of this paper is to study the conversion of mineral waste oils (MWO) containing heavy metals into valuable products via pyrolysis. The pyrolysis of the MWO has been carried out in a continuous-mode preparative scale pyrolysis unit containing a bed of char obtained from the Samca coal, a low-rank coal. Temperature of 625 °C and 700 °C and pressures of 0.1 and 1 MPa have been used. High yields of valuable light olefins as ethylene and propylene and light aromatics as BTX and naphthalene derivatives have been obtained. Special attention has been paid to the fate of the metals contained in the MWO during pyrolysis and their distribution into the pyrolysis products. In particular, the distribution of six metals (Cd, Ni, Pb, Cu, Cr, V) has been studied. The data show that the Samca coal chars used has the ability to take up some of the metals under study, but the behavior of each metal is different. So, while Pb and Cu are mostly retained in the coal char bed, V is not affected, and Cd, Ni, a...

The supercritical fluid extraction (SFE) of several organochlorine and organophosphorus pesticides and two metabolites, o,p-DDE and 4,4‘-dichlorobenzophenone, from recycled plastics was studied. The recycled plastics, used as agricultural soil covers, were a mixture of low-density polyethylene (∼90% w/w) and ethylene−vinyl acetate copolymer (∼10% w/w). The SFE was optimized and compared to the classical sonication and total dissolution extraction methods. The plastic was extracted with supercritical CO2 at different extraction conditions, depending on the physical matrix characteristics. Average recoveries of the 11 chemicals under study ranged from values greater than 90% with an overall relative standard deviation of 4.3% for plastic film to values lower than 40% with an overall standard deviation of 7.2% for plastic pellets. The variables affecting the whole extraction process, and the results obtained in the comparison between the three extraction methods were discussed.

The absorption of some organochlorine and organophosphorus pesticides on low-density polyethylene (LDPE) films used as agricultural soil covers is studied. Four different types of LDPE films (black, normal, thermic, and extra low density) and a copolymer of ethylene and vinyl acetate (EVA) were selected to do the kinetic study. Temperature ranged from 24 to 50 °C, and contact time between plastic films and a standard solution of pesticides in aqueous phase varied between 3 and 20 days. As pesticides the following were studied: dicloran, malathion, procymidone, folpet, α- and β-endosulfan, chlorothalonil, chlorpyriphos, and methylchlorpyriphos. Kinetic equations of first order were obtained in all cases having kinetic constants from 6.5 × 10-4 to 1 × 10-4 days-1. Most of the pesticides studied were completely absorbed on the plastic films after 15 days of contact time. No degradation of pesticides was observed once they were absorbed on the plastic. Both the absorption process and the capacity of absorpti...

A new procedure to determine styrene in olive oil, a simulant of fatty food, is presented. The method is bred on the coevaporation of styrene with a solvent of low boiling point at 90 o C. The vapors obtained are condensed in a frozen syringe, and this liquid is injected in GC/MS/SIM mode. The method hr been validated using deuterated styrene (d s ) and α-methylstyrene as internal standards. The detection limit is 10 μg/kg with a relative standard deviation (RSD) of 5% for 50 μg/kg styrene in olive oil

A new method of extraction of DEHA, bis(2-ethylhexyl) adipate, plasticizer from a matrix containing a high amount of fat matter, such as cheese, has been developed. By using an ultrasonic bath and hexane as the extracting solvent, the cleanup step to separate the fat matter before the analysis of DEHA is unnecessary. The method is successfully applied in the study of migration of DEHA to several cheeses

A study was carried out with atomic absorption spectrometry (AAS), using a silica tube, to determine whether lead hydride could be generated in organic medium, using solvents N,N-dimethylformamide, formamide, and dimethyl sulfoxide. Pb(NO/sub 3/)/sub 2/ was used as standard of Pb(II) and PbO/sub 2/, Pb(C/sub 2/H/sub 3/O/sub 2/)/sub 4/, and PbR/sub 4/ (where R = CH/sub 3/ or C/sub 2/H/sub 5/) were used as standards for Pb(IV). It was found that even with wide ranges of NaBH/sub 4/ concentrations, type and concentration of the acid medium, and various oxidants, no plumbane is generated. However, the hydrogen given out in the decomposition of NaBH/sub 4/ carries the tetraalkyl compound to the silica tube. This tetraalkyl compound can be carried to the silica tube by CO/sub 2/, generated in situ by adding NaHCO/sub 3/ in acid medium, instead of using NaBH/sub 4/. This permits the determination of volatile organometallic lead. The optimal conditions for direct volatilization of PbR/sub 4/, delivery to the silica tube, and AAS measurement were determined. The detection limit was found to be 17 ppb of Pb in a 20-ml sample. The relative standard deviation is 2.31%. Pb was directly determined in several gasoline samples.