Electronic Prediction of Chemical Contaminants in Aroma of Brewed Roasted Coffee and Quantification of Acrylamide Levels.

The aim of this research was to apply an electronic device as indirect predictive technology to evaluate toxic chemical compounds in roasted espresso coffee. Fresh coffee beans were subjected to different thermal treatments and analyzed to determine volatile organic compounds, content of acrylamide and 5-hydroxymethylfurfural, sensory characteristics and electronic nose data. In total, 70 different volatile compounds were detected and grouped into 15 chemical families.

Electronic Nose and Gas Chromatograph Devices for the Evaluation of the Sensory Quality of Green Coffee Beans.

The aim of this work is to discriminate between the volatile org9anic compound (VOC) characteristics of different qualities of green coffee beans () using two analysis approaches to classify the fresh product. High-quality coffee presented the highest values for positive attributes, the highest of which being fruity, herbal, and sweet. Low-quality samples showed negative attributes related to roasted, smoky, and abnormal fermentation.

Inhibition of Botrytis cinerea in tomatoes by allyl-isothiocyanate release from black mustard (Brassica nigra) seeds and detection by E-nose.

The aim of this work is to delayed the postharvest development of Botrytis cinerea in tomatoes by releasing allyl-isothiocyanate (AITC) from mustard seeds at room temperature, and to discriminate the aromatic profile by using an electronic device (E-nose). Olfactory sensory analysis showed that tomatoes inoculated in the presence of AITC did not develop the microorganisms until the eighth day of storage. The highest inhibitory concentration of AITC was found in Day 3 (175.

Effect of elaboration process, crop year and irrigation on acrylamide levels of potential table olive varieties.

Background: Table olives are widely consumed in the Mediterranean diet, and several typical Spanish and Portuguese varieties could potentially be used as such. In order to ensure a good-quality product, the effect of different factors such as elaboration processes, irrigation conditions, crop year and their crossover interaction on acrylamide content and antioxidant compounds needs to be deeply studied.

Results: When looking through irrigation, regulated deficit irrigation (RDI) presented lower acrylamide levels than rainfed conditions for 'Cordovil de Elvas', 'Picual' and 'Verdeal Alentejana'.

Burn Defect and Phenol Prediction for Flavoured Californian-Style Black Olives Using Digital Sensors.

Californian-style black olives can undergo different chemical changes during the sterilization process that can affect their sensory and phenol characteristics. Thus, these olives were stuffed with flavoured hydrocolloids and submitted to different thermal sterilization treatments to assess sensory categories. The triangular test indicated that the panellists were able to discriminate between samples from different categories according to their aromas with more than 85% success.

Bioavailability of Phenolic Compounds in Californian-Style Table Olives with Tunisian Aqueous Olive Leaf Extracts.

Recent advances in biotechnology have ensured that one of the main olive tree by-products is olive leaf extract (OLE), a rich source in bioactive compounds. The aim of this work was to study the phenolic composition in different OLEs of three Tunisian varieties, namely, 'Sayali', 'Tkobri', and 'Neb Jmel'. The in vitro biodigestibility effect after 'Sayali' OLE addition to Californian-style 'Hojiblanca' table olives was also studied.

Evaluation of Tunisian Olive Leaf Extracts to Reduce the Bioavailability of Acrylamide in Californian-Style Black Olives.

The aim of this work was analyzing the use of olive leaf extracts (OLE) obtained from two local Tunisian olive tree cultivars 'Chemlali' and 'Sayali' to reduce the acrylamide in Californian-style black olives. The phenol profile, antioxidant, and antibacterial activity of the two OLE extracts were evaluated. The principal phenols found were hydroxytyrosol (1809.

E-Nose Discrimination of Almond Oils Extracted from Roasted Kernels.

Almonds contain around 50% fat with a health-promoting fatty acid profile that can be extracted by pressing to obtain high-quality oils. To improve oil sensory properties, the almonds can be subjected to roasting treatments before oil extraction. However, intense thermal treatments may cause the appearance of undesirable volatile compounds causing unpleasant aromas.

Evaluation of the Olfactory Quality of Roasted Coffee Beans Using a Digital Nose.

The roasting process is one of the critical points to obtain a product of the highest quality with certain sensorial properties including the aroma of coffee. Samples of coffee beans were roasted at different thermal treatment intensities with the aim of obtaining aromatic compounds detected with an electronic device. Sensory analysis, volatile compound profiling, and electronic nose analysis were carried out.

Application of Digital Olfaction for Table Olive Industry.

The International Olive Council (IOC) established that olives must be free of odors, off-flavors, and absent of abnormal ongoing alterations or fermentations. The use of electronic devices could help when classifying defects in a fast, non-destructive, cheap, and environmentally friendly way. For all of that, table olives were evaluated according to IOC regulation in order to classify the defect predominant perceiving (DPP) of the table olives and their intensity.

Masking Effect of Sensory Defect with Flavoured Stuffed Olives.

Carao () is an America native plant characterized by its high iron content. This particular property allows its use as a natural additive to fix the black colour in California-style black olives, while masking its unpleasant aroma by stuffing olives with flavoured hydrocolloid. The tasting panel evaluated olives filled with unflavoured hydrocolloid with a fruity aroma, classified them as an extra category.

Determination of the Masking Effect of the 'Zapateria' Defect in Flavoured Stuffed Olives Using E-Nose.

Spanish-style table olives are one of the most common processed foods in the Mediterranean countries. Lack of control during fermentation can lead to one of the main defects of the olive, called 'Zapateria', caused by the combination of volatile fatty acids reminiscent of rotten leather. In this study, table olives altered with 'Zapateria' defect were stuffed with a hydrocolloid flavoured with the aroma 'Mojo picón' to improve consumer acceptance.

Application of Electronic Nose to Discriminate Species of Mold Strains in Synthetic Brines.

The chemical composition of the brine for Spanish-style table olives plays a crucial role during the fermentation process. Traditional laboratory analysis requires a high consumption of reagents, highly qualified personnel, sophisticated equipment, long analysis times, and large amounts of samples. Analysis carried out using an electronic nose (E-nose) offers an alternative, non-destructive technique and is useful in determining alterations in brines caused by microorganisms.

Effect of High Hydrostatic Pressure in the Storage of Spanish-Style Table Olive Fermented with Olive Leaf Extract and .

Olives treated according to the Spanish-style are firstly treated with caustic soda and then fermented in brine to reduce phenols. Next, olives are packed and subjected to pasteurization. The effect of different high hydrostatic pressure treatments (400 MPa, 4 and 6 min) was evaluated in Spanish-style table olives fermented with olive leaf extract (OLE) and compared with thermal pasteurization (P) at 80 °C for 15 min.

Characterization of Polyphenol and Volatile Fractions of Californian-Style Black Olives and Innovative Application of E-nose for Acrylamide Determination.

Californian-style black olives require a sterilization treatment that produces a carcinogenic contaminant, acrylamide. Thus, this compound was evaluated in two different olive cultivars using an electronic nose (E-nose). The sterilization intensity had a significant influence on the final phenol concentrations, acrylamide content, and volatile compounds.

Electronic nose application for the discrimination of sterilization treatments applied to Californian-style black olive varieties.

Background: Olive oil continues to be the main destination for olives. The production of table olives is increasing. 'Californian-style' processes are among the most frequently employed to produce oxidized olives.

E-Nose Discrimination of Abnormal Fermentations in Spanish-Style Green Olives.

Current legislation in Spain indicates that table olives must be free of off-odors and off-flavors and without symptoms of ongoing alteration or abnormal fermentations. In this regard, the International Olive Council (IOC) has developed a protocol for the sensory classification of table olives according to the intensity of the predominantly perceived defect (PPD). An electronic nose (e-nose) was used to assess the abnormal fermentation defects of Spanish-style table olives that were previously classified by a tasting panel according to the IOC protocol, namely zapateria, butyric, putrid, and musty or humidity.

Effects of Different Controlled Temperatures on Spanish-Style Fermentation Processes of Olives.

This work aimed to determine the effect of applying different temperatures during the fermentation process of Spanish-style table olives. 'Manzanilla de Sevilla' (southwest of Spain, Badajoz) and 'Manzanilla Cacereña' (northwest of Spain, Caceres) olives were processed at an industrial scale in table olive fermenters whose brine was subjected to different thermal treatments. One of the three conducted experiments found that maintaining brine at 20-24 °C over a 3-month period led to optimum firmness, better color indices, and greater free acidity and lactic acid bacteria populations in comparison to an unheated control.

Industrial Strategies to Reduce Acrylamide Formation in Californian-Style Green Ripe Olives.

Acrylamide, a compound identified as a probable carcinogen, is generated during the sterilization phase employed during the processing of Californian-style green ripe olives. It is possible to reduce the content of this toxic compound by applying different strategies during the processing of green ripe olives. The influence of different processing conditions on acrylamide content was studied in three olives varieties ("Manzanilla de Sevilla", "Hojiblanca", and "Manzanilla Cacereña").

Combination of fluorescence excitation emission matrices in polar and non-polar solvents to obtain three- and four- way arrays for classification of Tempranillo grapes according to maturation stage and hydric status.

The applicability of front-face excitation-emission fluorescence spectroscopy to compare grape water extracts of two consecutive sampling dates, corresponding with two maturation stages, and subjected to full irrigation and non-irrigation, was carried out. The decomposition of the obtained three way grape samples was initially analyzed by means of parallel factor analysis (PARAFAC). A tentative identification of fluorophores was done by matching PARAFAC score values with HPLC measurements.

Monitoring of acrylamide and phenolic compounds in table olive after high hydrostatic pressure and cooking treatments.

Acrylamide and phenolic compounds on both fresh and cooked olives were monitored by HPLC/MS-MS and reversed-phase-HPLC methods along different procedures: elaboration process, high hydrostatic pressure (HHP), cooking treatment and bioavailability evaluation. Acrylamide was not detected during the elaboration process and after HHP treatment. Hydroxytyrosol, tyrosol, oleuropein and verbascoside were the most important phenols after HHP treatment.

Front-face fluorescence excitation-emission matrices in combination with three-way chemometrics for the discrimination and prediction of phenolic response to vineyard agronomic practices.

Phenolic extracts from cv Tempranillo grapes subjected to water stress and irrigation treatment, both of them with high and low crop load, were analyzed by front-face fluorescence. Excitation-emission matrices (EEMs) were analyzed by means of unsupervised parallel factor analysis (PARAFAC), PARAFAC supervised by linear discriminant analysis, and discriminant unfolded partial least-squares. All algorithms allowed to differentiate between water stress and irrigation grape samples when the fluorescence maxima region of catechin and epicatechin, and resveratrol was considered.

Bioavailability, composition and functional characterization of extracts from Oryza sativa L. bran.

The aim of this study has been to assess the composition and antioxidant activities of rice bran extracts submitted to a human simulated digestion, which extraction process was previously optimized. In order to adjust the optimum values for the extraction, D-optimal experimental design and response surface methodology have been applied. Phenolic compounds and γ-oryzanol contents have been used as response parameters.

High resolution mass approach to characterize refrigerated black truffles stored under different storage atmospheres.

Freshly harvested Tuber melanosporum samples were packed and stored at 4°C under reduced atmospheric pressure or modified atmosphere for four weeks. Multivariate analysis was employed to correlate the antioxidant power of the ethanolic extracts of the samples with the chemical composition determined by high resolution mass spectrometry. High performance liquid chromatography coupled with a coularray detector was applied to select the chemical species associated with the antioxidant power.

Optimization and validation of a rapid liquid chromatography method for determination of the main polyphenolic compounds in table olives and in olive paste.

A high performance liquid chromatography method, coupled to diode-array and fluorescence detectors, with a previous solid-liquid extraction, has been developed for the simultaneous detection and quantification of polyphenolic compounds in table olives and in olive paste. The effects of extraction variables have been studied by response surface methodology. The best conditions were extraction with 100% methanol (2mM NaF) during 30min for table olives, and 91% methanol (2mM NaF) during 40min for olive paste.