Characterization of the aroma profile of edible flowers using HS-SPME/GC-MS and chemometrics.

In recent years the consumption of edible flowers has gained new popularity, and their use seems destined to grow thanks to their potential as functional elements and their ability to impart aroma to traditional foods. In this study, the volatile profile of several edible flowers was investigated to identify characteristic compounds to be used as product markers. 85 samples belonging to four cultivars were analyzed by HS-SPME/GC-MS. A PLS-DA was used to build a model capable of differentiating the investigated classes. The resulting model correctly predicted over 95% of the validation samples, highlighting a significant difference between the four types of edible flowers. The VIP analysis highlighted 29 compounds relevant for the characterization of different flowers, many of which were biologically active. The study aims to broaden the framework of objectively measurable tools useful for enhancing the qualitative peculiarity of one product compared to another and offering growth opportunities to emerging food chains.

Effects of thermal treatments on durum wheat pasta flavour during production process: A modelling approach to provide added-value to pasta dried at low temperatures.

Pasta is a key element of the Mediterranean Diet and it has been declared by Unesco intangible cultural heritage of humanity. Despite seems a simple food, only made of semolina and water, pasta is produced following a multi-step process that strongly affect the final product. Drying stage is the one that has the greater influence on its organoleptic/nutritional characteristics. This study aimed to analyse the flavour of pasta to test whether the different drying treatments (High Temperature-Short time or Low Temperature-Long time) have a direct impact on its composition and consequently whether they could influence the end-product quality. The headspace solid-phase microextraction was optimized using an experimental design and 52 samples were analysed by HS-SPME/GC-MS and classified by PLS-DA. The resulting classification model (validated by repeated double cross-validation and permutation tests) allowed correctly predicting more than 80% of samples, confirming that drying may have a significant impact on pasta flavour.

Monitoring of contaminants in recycled paperboard for food contact applications.

BACKGROUND: The lack of harmonized European legislation on food packaging led the Confederation of European Paper Industries to the proposal of a voluntary Industry Guideline for the compliance of paper and board materials for food contact applications. In the present work, a previously established method for the simultaneous determination of contaminants commonly found in recycled paperboard was improved and its applicability as a quality control tool in the paper industry was also assessed. The method involves a sample pre-treatment followed by gas chromatography/mass spectrometry (GC/MS) analysis. RESULTS: For analysis, paperboard samples were collected both from three sections of the same reel and from different reels belonging to the same production run. Results highlighted no significant differences in terms of contaminant distribution among samples, which ensured good sampling representativeness. The performance of the method was considerably improved in terms of linearity range, limits of detection and quantification (5- to 2-fold lower) by using a quadrupole GC/MS system instead of an ion trap GC/MS system. CONCLUSION: The proposed method could offer a key strategy for analysis of benzophenone derivatives, diisopropyl naphthalene and phthalates in recycled paperboard in order to assess compliance of food packaging with the voluntary limits recommended by the Industry Guideline. © 2016 Society of Chemical Industry.

Characterization of the Authenticity of Pasta di Gragnano Protected Geographical Indication Through Flavor Component Analysis by Gas Chromatography-Mass Spectrometry and Chemometric Tools.

An authentication study based on headspace solid-phase microextraction/GC-MS was performed with a set of 60 samples representative of traditional "Pasta di Gragnano protected geographical indication (PGI)" and the most common Italian pasta brands. Multivariate chemometric tools were used to classify the samples based on the chemical information provided from 20 target flavor compounds, including Maillard reaction and lipid oxidation products. Pattern recognition by principal component analysis and linear discriminant analysis showed a natural grouping of samples according to the drying process adopted for their production (i.e., the traditional Cirillo method versus a high-temperature approach). Subsequently, soft independent modeling by class analogy (SIMCA) and unequal dispersed classes (UNEQ) were used to build class models at 95% confidence and 100% sensitivity levels (forced models) for predictive classification purposes. The good performance obtained from the models in terms of cross-validation efficiency (SIMCA, 57.01%; UNEQ, 86.60%; 100% for both forced models) highlighted that targeted analysis of flavor profiles could be used to assess the authenticity of Pasta di Gragnano PGI samples. Hence, the proposed method may help to protect Pasta di Gragnano PGI from label frauds by verifying whether samples comply with statements concerning drying process conditions as stated in the product specification.

Furosine as a pasta quality marker: evaluation by an innovative and fast chromatographic approach.

A fast and simple high-performance liquid chromatography method suitable for determining furosine level in heat-treated food samples was developed. The analysis of furosine was performed by a novel mixed-mode column that provides multiple and simultaneous retention mechanisms including cation-exchange, anion-exchange, reversed-phase, or hydrophilic interaction. Each retention mechanism could be independently controlled by setting chromatographic conditions. Adequate retention and selectivity of polar charged furosine were achieved by adjusting mobile phase pH, buffer concentration, organic content, and ionic strength. The optimized method was successfully applied to determinate furosine in durum wheat semolina pasta samples. Furosine level in pasta may be used as a reliable marker of health and nutritional damage occurring during pasta manufacture. Indeed, a low content of furosine is generally related to high nutritional quality of food and application of mild heat treatments. A wide range of dry pasta samples, collected from both supermarkets (large-scale retail trade) and shops selling local products, were analyzed. Variable amounts of furosine, ranging from 107 to 506 mg/100 g of protein, were found in pasta samples. The proposed method allows to discriminate products submitted to different time-temperature conditions during the drying process. At the same time, it may be used to highlight potential label fraud.

Direct immersion-solid phase microextraction for the determination of chlorinated pesticide residues in tomatoes by gas chromatography with an electron capture detector.

The use of pesticides in agriculture has grown dramatically over the last decades. Environmental exposure of humans to agrochemicals is common and results in both acute and chronic health effects. In this study, direct immersion-solid phase microextraction (SPME) was coupled with electron capture detection for trace determination of 19 chlorinated pesticides in tomato samples, using a 100 pm polydimethylsiloxane fiber. The experimental parameters extraction time, extraction temperature, stirring, and salting out were evaluated and optimized. The LODs ranged from 0.5 to 8 microg/kg, and the LOQs from 5 to 30 microg/kg. A linear response was confirmed by correlation coefficients ranging from 0.97 to 0.9985. The developed method was tested by analyzing real samples purchased within the network of Italian distribution. The samples were found to be free from detectable residues of the studied pesticides. SPME has been shown to be a fast extraction technique that has several advantages such as solvent-free extraction, simplicity, and compatibility with the chromatographic analytical system.

Development of a headspace-solid phase microextraction-gas chromatography method to determine organohalogen contamination in drinking water.

The formation of organohalogen compounds in waters treated by chlorination has drawn increasing scientific attention due to the potentially hazardous health effects of this class of substances. Today, chlorination is the most widely used technology for civil water disinfection. In this study, headspace-solid phase microextraction coupled with GC-electron capture detector was used to determine organohalogen compounds in drinking water sampled from aqueducts and artesian wells in Italy. Experimental parameters, such as sample volume, stirring, salting out, extraction temperature, and extraction time, were evaluated and optimized. The LODs ranged from 1 to 10 ng/L and LOQs from 5 to 50 ng/L. A linear response was confirmed by correlation coefficients ranging from 0.9443 to 0.9999. Quantifiable organohalogen residues were found in 11 water samples, with concentration up to 11.3 +/- 0.5 microg/L for the sum of all trihalomethanes and 0.66 +/- 0.03 microg/L for the sum of trichloroethylene and tetrachloroethylene. These concentrations are lower than the current regulatory limits in Italy.

Multiresidue method for the determination of organophosphorus pesticides in cereal matrixes.

Our research was focused on a preliminary comparison of three cleanup procedures for the determination of 26 organophosphorus (OP) pesticide residues in cereal matrixes. The aim of the study was to reduce the analytical problems associated with the presence of high-molecular-weight compounds in these matrixes in order to improve the efficiency of the chromatographic separation. The method was based on the extraction of OP pesticides from the samples with the use of petroleum ether, acetone, and dichloromethane, and on three different cleanup procedures, followed by GC identification. The first procedure was carried out with a multicartridge system; the second procedure consisted of a low-temperature lipid precipitation; for the third procedure, acid and neutral alumina were used for cleanup of the extract. The use of deactivated acidic alumina as the adsorbent medium and the use of n-hexane-dichloromethane-ethyl acetate (6 + 3 + 1, v/v/v) as the eluting system were preferred. After purification, the residue was injected into a gas chromatograph for separation followed by nitrogen-phosphorus detection; the identities of the OP pesticides in positive samples were confirmed by GC/MS. The proposed method could be extended to the determination of other OP pesticides in various food matrixes in routine analysis.