Core-Shell Columns in High-Performance Liquid Chromatography: Food Analysis Applications

Theincreased separation efficiency provided by the newtechnology of column packed with core-shell particles in high-performance liquid chromatography (HPLC) has resulted in their widespread diffusion in several analytical fields: from pharmaceutical, biological, environmental, and toxicological.The present paper presents their most recent applications in food analysis.Their use has proved to be particularly advantageous for the determination of compounds at trace levels or when a large amount of samples must be analyzed fast using reliable and solvent-saving apparatus. The literature hereby described shows how the outstanding performances provided by core-shell particles column on a traditional HPLC instruments are comparable to those obtained with a costly UHPLC instrumentation, making this novel column a promising key tool in food analysis

Nutritional and sensory evaluation of ready-to-eat salads during shelf life

The evolution of the antioxidant and sensory properties of six commercially available ready-to-eat salads, rocket, iceberg lettuce, baby lettuce, lamb’s lettuce, curly endive and radicchio, was studied throughout the shelf life. Both the storage under modified atmosphere and in unsealed pouch in a domestic refrigerator were considered and compared. Ascorbic acid, total phenolics content and antioxidant capacity were chosen as the most representative nutritional parameters for this purpose. The data obtained were analyzed by Principal Component Analysis (PCA). Radicchio, lamb’s lettuce and rocket showed an initial higher content of the quality parameters studied and demonstrated a better resistance to air exposure than the other salads, being ascorbic acid the most affected parameter. Modified atmosphere packaging demonstrated to be a very useful and reliable technology to extend nutritional and sensory properties during the shelf life period for all the vegetables studied

Effect of Steaming and Boiling on the Antioxidant Properties and Biogenic Amines Content in Green Bean (Phaseolus vulgaris) Varieties of Different Colours

Effects of boiling and steaming cooking methods were studied on total polyphenols, antioxidant capacity, and biogenic amines of three green bean varieties, purple, yellow, and green.The vegetables gave good values both for antioxidant capacity and for phenolics content, with the purple variety being the richest in healthful components. Both the heat treatments affected the antioxidant properties of these vegetables, with boiling that reduced the initial antioxidant capacity till 30%in the yellowvariety, having the same trend for total polyphenols, with the major decrement of 43% in the green variety. On the contrary, biogenic amines significantly increased only after boiling in green and yellow variety, while purple variety did not show any changes in biogenic amines after cooking. The steaming method showed being better cooking approach in order to preserve the antioxidant properties of green beans varieties and to maintain the biogenic amines content at the lowest level

Fast determination of biogenic amines in beverages by a core-shell particle column

A fast and reliable HPLC method for the determination of 11 biogenic amines in beverages has been performed. After pre-column derivatization with dansyl-chloride a Kinetex C18 core–shell particle column (100 mm × 4.6 mm, 2.6 μm particle size) has been employed and the biogenic amines were identified and quantified in a total run time of 13 min with ultraviolet (UV) or fluorescence detection (FLD). Chromatographic conditions such as column temperature (kept at 50 °C), gradient elution and flow rate have been optimized and the method has been tested on red wine and fruit nectar. The proposed method is enhanced in terms of reduced analysis time and eluent consumption with respect of classical HPLC method as to be comparable to UHPLC methods. Green and cost-effective, this method can be used as a quality-control tool for routine quantitative analysis of biogenic amines in beverages for the average laboratory

Verifica della autenticità e qualità di prodotti alimentari: metodologie e applicazioni

In recent years food safety and quality have become a principal demand of the citizen, and the determination of food authenticity and geographical origin is now a crucial issue both for consumer choice and for food authorities, as demonstrated by the promulgation of several laws regarding food labeling, traceability and authenticity. Products with any labels or indications are perceived by consumers as high-quality food products, for reasons that vary from specific culinary or organoleptic qualities associated with regional products, health safety, and patriotism, to concern about animal welfare and environmentally friendly production methods. This allows producers to obtain market recognition and premium, and many suffer from piracy of their brands. In this contest, the analytical authentication of what is declared on labels is of fundamental importance to assure producers against fair competition and consumers against harmful fraudulent practices. In this work three food sectors of relevant impact on European economy are examined: Italian wine, fruit juices and milk from organic agriculture. All these sectors are examined in relation to European regulation, market features and analytical tools for their authentication described in literature. The experimental part describes innovative methods for the authenticity assessment of these food matrices. Biogenic amines fingerprinting have been used for Italian red wines and fruit juices, while 13C/12C isotopic ratio for milk from organic agriculture. The results, after being processed by chemometric techniques, are quite encouraging, in fact biogenic amines succeeded in discriminating Italian red wines for retail price segment and grape variety, while fruit juices for species of origin. This is the first research conducted on the presence of these natural contaminants in fruit juices and its data had proven to be useful both toxicological and authentication points of view. The analysis were conducted with an improved chromatographic method that allowed to shorten analysis time and save chemicals. Also the results obtained from the analysis of 13C/12C isotopic ratio of milk allowed to differentiate to conventional milk from organic milk, demonstrating to be a reliable marker for this kind of production verification. The studies hereby described highlight the importance of pursuing greater importance and diffusion of analytical controls in food authentication, by official institutions and private firms, as a powerful tool to avoid counterfeiting in food products, to enhance consumer trust and for commercial valorization of peculiar food products’ characteristics

Chemometric evaluation of biogenic amines in commercial fruit juices

The profile and level of 11 biogenic amines were evaluated in commercial fruit juices (apple, grapefruit, orange and pineapple) and fruit nectars (apricot, peach and pear) by HPLC/FD after dansyl chloride derivatization. The biogenic amine most present in nectars is cadaverine, followed by putrescine, spermidine and spermine. Fruit juices showed a wider variability in biogenic amines profile and level, with the highest total content in orange juices. The application of chemometric tools as hierarchical cluster analysis and principal component analysis on the biogenic amine profiles of the juice samples succeeded in grouping juices on the basis of the fruit of origin. A Mathematical model with high predictive ability for fruit juices classification was obtained by linear discriminant analysis: orange (100 %), pineapple (100 %), grapefruit (80 %) and apple (70 %). This study represents the first description of biogenic amines content in these beverages. These compounds are well-known important quality parameters and demonstrated to have also a characteristic profile depending on the fruit of origin

Simplified analytical method for the determination of ascorbic and dehydroascorbic acids in freshly consumed salads.

The market of freshly consumed salads is increasing rapidly, due to the consumer perception of healthiness, their ease to use, and the constant recommendations by many health authorities for a consumption of at least 5 portions of fruit and vegetables by day. Vitamin C, including ascorbic acid (AA) and dehydroascorbic acid (DHA), has many biological activities in the human body. The content of vitamin C in fruits and vegetables can be influenced by various factors such as genotypic differences, preharvest climatic conditions and cultural practices, maturity and harvesting methods, and postharvest handling procedures (1). Moreover, owing to the lability of vitamin C, the foodstuff content in this compound is frequently used as an indicator of quality and freshness. The determination of vitamin C in freshly consumed salads has therefore a double target: to assess the nutritional value for human vitamin C intake, and to act as a marker of product quality. Many analytical methods, based on different techniques, are reported in the literature for the quantitative determination of vitamin C, but HPLC has demonstrated to be the most reliable (2). The extraction procedure required in vegetables is usually quite time and solvent consuming, involving two or three extraction steps to achieve good recoveries, due mainly to the complexity of the matrix, often with strong cellular walls that encage the analytes. In the present study the application of HPLC to the determination of AA and DHA levels in some freshly consumed salads is described. The method was applied to six varieties of commonly consumed salads: three were vegetables with a soft texture (rocket, red oak leaf, and baby lettuce), the remaining had an harder texture (escarole, continental and romaine lettuce). In order to optimize and to make easier the overall procedure we have introduced some modifications both in the sample pretreatment operations, by the use of an ultrasonic bath, and in the chromatographic determination, with an aqueous mobile phase, achieving good recoveries (> 90%) and repeatability. Therefore the method demonstrated to be suitable for routine analysis. The vitamin C content observed was in the following order : rocket > continental > red oak leaf > baby lettuce > escarole > romaine lettuce

Biogenic Amine Content in Red Wines from Different Protected Designations of Origin of Southern Italy: Chemometric Characterization and Classification

Biogenic amines are contaminants naturally present in wines. Their occurrence is influenced by several factors including oenological and agricultural practices, grape variety, and geographical origin. For these reasons, they have been chosen as marker to characterize and classify 56 Italian red wines belonging to four protected designations of origin (PDO) from Southern Italy. Principal component analysis and cluster analysis were applied on data obtained by HPLC/RF in order to highlight the natural grouping of samples. Afterward, linear discriminant analysis and partial least squares were used to classify the wines according to their PDO. Biogenic amines are demonstrated to be a reliable and useful marker for the characterization and classification of the four Southern Italian PDOs investigated. Both the linear discriminant analysis (LDA) and the partial least squares discriminant analysis (PLS-DA) achieved 100 % of wines correctly classified and predicted. Therefore, the determination of these compounds in red wines can play an important role in wine quality assessment, by providing information for the prevention of potential detrimental effects on health and for the characterization of PDO labeled wines

Chemometric evaluation of the antioxidant properties and phenolic compounds in Italian honeys as markers of floral origin

Italian honeys from different floral sources (acacia, orange, honeydew, chestnut, strawberry tree, sulla, eucalyptus, dandelion, linden, polyfloral) were analysed in terms of colour, total phenolic content, in vitro antioxidant capacity and content of 15 phenolic compounds. Physicochemical parameters were also examined to assess the overall quality of honey. Dark honeys demonstrated to have the highest content in bioactive compounds and in antioxidant activity with the highest values in strawberry tree and honeydew honeys. Data were processed using principal component analysis (PCA), hierarchical cluster analysis (HCA) and linear discriminant analysis (LDA). The overall classification capacity for the 9 unifloral honey varieties obtained by LDA was 100.00%, with a very low level of prediction misclassification in cross validation (less than 5%). This study demonstrates the strong relation between honey floral origin and bioactive compounds profile and amount, together with the importance of colour attributes as a simple approach for a preliminary evaluation of the antioxidant properties and floral origin discrimination

Monitoring of Pesticides Residues in Italian Mineral Waters by Solid Phase Extraction and Gas Chromatography Mass Spectrometry

Twenty-two pesticides and metabolites, selected on the basis of regional priority lists, were surveyed in thirty Italian mineral waters springs for three years by a procedure based on solid phase extraction in combination with gas chromatography coupled with mass spectrometry detection. The procedure proved to be simple, sensitive and reliable, the limits of detection and relative standard deviations were respectively in the range of 0.002 - 0.04 μg/L and 3% - 7%, recoveries ranged from 86% to 105% at the European Union Maximum Acceptable Concentration (MAC). Pesticide residues were detected in just one of the ninety water samples analyzed but no one exceeding the MAC. These results demonstrate the good quality of Italian mineral waters, not forgetting the need of constant revision and update of the priority list of pollutants