Impact of semolina-barley mixture on the volatolomic profile of dough and pasta: characterization by a multivariate chemometric approach.

BACKGROUND: Barley flour, known to be rich in various phytochemicals, has been demonstrated to improve the technological and nutritional properties of pasta; however, its volatile profile, on which its aromatic properties depend, also plays an important role in the acceptance of barley-enriched pasta. In the present work, volatile organic compounds (VOCs) of semolina doughs enriched with different percentages of barley and of the related pasta were characterized by solid phase micro-extraction (HS-SPME) coupled to gas-chromatography/mass spectrometry (GC-MS), and evaluated using a multivariate statistical approach, including principal component analysis (PCA), cluster heatmaps, Pearson's and Spearman's correlations, and partial least squares correlation (PLSC). RESULTS: The effects of single raw materials, and their interactions, were studied to establish their importance in the volatile profile of the samples, and the correlation between the dough VOCs and the processed product VOCs was assessed. The presence of barley flour markedly affected the volatile profile in comparison with the dough obtained with only durum wheat. For alcohols, esters, terpenes, and some aldehydes there was a clear correlation with the percentage of barley. For some of the VOCs, on the other hand, a strong dependence on the ingredients interaction effect due to the mixing stage has been demonstrated. CONCLUSION: The heatmaps allowed a good graphical visualization of the relationship between molecules and barley percentage, offering the possibility to select the best one according to the desired volatolomic footprint. Pasta with 40% of barley was demonstrated to give pasta with the most complex volatile profile. © 2024 Society of Chemical Industry.

Evolution of phenolic and volatile compounds during bottle storage of a white wine without added sulfite.

BACKGROUND: Bottle storage can affect color, aroma and phenolic composition of white wine. Very little information is reported about the bottle evolution during storage of white wines without added sulfites and/or using other antioxidants. This work is aimed at studying the evolution of the main enological parameters, phenolic and volatile profiles of a white wine without added sulfites, during 15 months of storage in bottle at different light and temperature conditions, compared with a control stored with sulfur dioxide. Dark storage at 12 °C (D12-S, D12-NS) and 30 °C (D30-S, D30-NS) were compared to investigate the temperature effect, meanwhile uncontrolled temperature and light condition (UTL-S, UTL-NS) simulated improper storage conditions. RESULTS: Volatile acidity, absorbance at 420 nm and total phenols were higher in UTL-NS and D30-NS wines. The trans forms of hydroxycinnamic esters decreased, whereas, the cis forms, as well as caffeic acid derivatives, significantly increased in samples without added sulfites. The storage without sulfites also accelerated the hydrolysis of acetate esters. However, it did not affect most of the ethyl esters whose content remained almost the same between sulfite added (S) and no sulfite added (NS) wines. CONCLUSION: The presence of sulfites in the bottle helped to preserve the volatile compounds of young wines; however, even more important seemed to be the optimal storage (dark and low temperature), as unsuitable conditions favored aroma degradation of bottled wine, regardless of sulfite protective action. © 2019 Society of Chemical Industry.

Efficacy of yeast starters to drive and improve Picual, Manzanilla and Kalamàta table olive fermentation.

BACKGROUND: Table olive fermentation is an unpredictable process and frequently performed using traditional practices often inadequate to obtain products with acceptable quality and safety standards. In the present study, the efficacy of selected yeast strains as starters to drive fermentations of green and black table olives by the Greek method was investigated. Pilot-scale production by spontaneous fermentation as a control, olives started with previously selected Saccharomyces cerevisiae strains and fermentation driven by commercial S. cerevisiae baker's yeast strain were carried out for each of Manzanilla, Picual and Kalamàta table olive cultivars. RESULTS: Time of fermentation was significantly shortened to 40 days to complete the transformation process for all three tested cultivars. Inoculated table olives were enhanced in their organoleptic and nutritional properties in comparison with corresponding samples obtained by spontaneous fermentation. The use of starters was also able to improve safety traits of table olives in terms of biogenic amine reduction as well as absence of undesired microorganisms at the end of the process. CONCLUSIONS: Autochthonous, but also non-autochthonous, yeasts can be used to start and control table olive fermentations and can significantly improve quality and safety aspects of table olives produced by many smallholder farmers. © 2018 Society of Chemical Industry.

Effect of modified atmosphere packaging and temperature abuse on flavor related volatile compounds of rocket leaves (Diplotaxis tenuifolia L.).

The effect of storage conditions on flavor-related volatile composition of wild rocket (Diplotaxis tenuifolia) was investigated on Modified Atmosphere packed (MAP) leaves stored under isothermal and non-isothermal conditions. In a first experiment the effect of MAP was compared to the storage in air at 5 °C; a second experiment aimed to study the effect of non isothermal conditions, with two temperature abuses (at 13 °C for 24 h) during a 5 °C. Twenty-four volatiles were detected, including C6, C5, isothiocyanate, lipid-derived and sulfur compounds. In the first experiment, MAP-stored rocket showed a slower loss of typical flavour volatiles (thiocyanates and isothiocyanates) and a slower production of off-flavors until 6 days of storage, compared to leaves stored in air. After this time, dimethyl sulfide and acetaldehyde dramatically increased in MAP-stored rocket samples. In the second experiment, samples stored under non-isothermal conditions showed lower O2 and higher CO2 concentrations than samples stored under isothermal conditions. Rocket leaves stored under non-isothermal conditions showed an increased production of volatiles responsible of off-flavors (acetaldehyde and dimethyl sulfide) following temperature abuse comparing to storage in isothermal condition. Thus, dimethyl sulfide and acetaldehyde could be effective markers for tracking the effect of temperature fluctuations on rocket during storage.

Effect of harvest time on table grape quality during on-vine storage.

BACKGROUND: Postponing the harvest of grapes is a common practice in southern Italy, in order to delay harvest up to Christmas and make higher income from their sale. The aim of this work was to evaluate the effect of harvest time (over almost 3 months) on the quality of table grapes (cv. Italia). The experiment was repeated for two years (2010 and 2011). In 2010, grapes were harvested starting from 8 October and after 11, 27 and 48 days. In 2011, five harvest times were compared over a period of 56 days. Respiration rate, firmness, colour, sensory attributes, total soluble solids (TSS), pH, titratable acidity (TA), phenols and antioxidant activity were measured. In addition, in the second year, volatile compounds were evaluated. RESULTS: For both years, harvest time influenced most parameters, which indicated that metabolic changes took place in the plants. In 2010, harvest time influenced respiration rate, cluster and berry appearance scores, colour attributes, crunchiness, pH, TA, total phenol content and antioxidant activity. In 2011, harvest time influenced respiration rate, colour attributes, most sensory attributes, TSS and TA. Generally, late harvested grapes showed higher firmness, berry appearance score, sweetness, fruity taste, overall sensory evaluation score and TSS. Regarding volatile compounds, terpene content decreased during ripening, while C6 compounds showed a nonlinear trend. CONCLUSION: The results showed that table grape sensory quality could be increased by delaying harvest up to a certain time of the season, while excessive delay could reduce final grape quality.

Use of Multivariate Statistics in the Processing of Data on Wine Volatile Compounds Obtained by HS-SPME-GC-MS.

This review takes a snapshot of the main multivariate statistical techniques and methods used to process data on the concentrations of wine volatile molecules extracted by means of solid phase micro-extraction and analyzed using GC-MS. Hypothesis test, exploratory analysis, regression models, and unsupervised and supervised pattern recognition methods are illustrated and discussed. Several applications in the wine volatolomic sector are described to highlight different interactions among the various matrix components and volatiles. In addition, the use of Artificial Intelligence-based methods is discussed as an innovative class of methods for validating wine varietal authenticity and geographical traceability.

Evaluation of Quality and Storability of "Italia" Table Grapes Kept on the Vine in Comparison to Cold Storage Techniques.

The aim of the study was to compare the quality of table grapes (cv. Italia) held on the vine compared to grapes stored in cold rooms with or without modified-atmosphere packaging (MAP). The grapes were harvested from 12 plants in 2 vineyards in the same area, differing for the age of the plant. Four- and a fourteen-year-old vines were cultivated with the "Apulia tendone" system. After the first harvest, grapes were divided into small clusters and used for storage treatments in air and in MAP. Samples of 400 g were packaged in polypropylene (PP) trays sealed with a polypropylene/polyamide (PP/PA) film with 20% CO2 in air. MAP and control samples were then stored in the same cold room at 0 °C. Initially and after 8, 21, and 28 days, grapes stored in air and MAP were compared to fresh harvested grapes, stored on the plants. Quality attributes included color, texture, maturity index, phenols, antioxidant activity, sugars, organic acids, sensory parameters, and volatile compounds. The results obtained demonstrated that grapes held on the plant and in MAP showed better quality in terms of appearance scores compared to grapes stored in air. In particular, the application of high CO2 contributed to reduce the deterioration rate of the clusters, minimizing weight loss, and delaying degradation processes, and this particularly for grapes from the 14-year-old vine, where grapes held on the plant degraded faster than grapes in the younger vines. Most volatile compounds did not change their concentration with the storage treatment, except for ethyl acetate and ethanol, which increased in MAP at the end of storage, and to some compound responsible for green odor. In conclusion, keeping the grapes on the plant can be considered a good agronomic practice to preserve the quality, whereas MAP can be applied to better maintain postharvest quality of the product throughout storage and distribution.

Effect of Soil Management and Training System on Negroamaro Wine Aroma.

This study aimed to assess the impact of two soil managements and training systems on yield and wine aroma compounds of Negroamaro variety grown in a warm climate region (southern Italy). Cover crop (CC) and soil tillage (ST) as soil management, whilst bilateral Guyot (BG) and monolateral Guyot (MG) as training systems were compared. Free and bound volatile fractions were evaluated by GC-MS. ST and CC as well as BG and MG significantly affected yield parameters. In particular, yield was higher in ST and BG than in CC and MG, respectively; moreover, it was found to be positively influenced by interaction between BG and ST. Regarding aroma compounds, significant interactions between soil management and training system factors were observed. In case of free volatiles, the most positive interaction was found between BG and ST, whereas, for bound volatiles, the best interaction was represented by MG with both soil tillage and cover crop. Vine leaf area and development over vine growth stages along with water stress levels played an important role in determining the aroma profile as well as yield parameters. In conclusion, the training system significantly interacted with soil management and affected most of important aroma compounds in Negroamaro wine.

Use of microfungi in the treatment of oak chips: possible effects on wine.

BACKGROUND: Oak barrels are commonly used in the aging of wines and spirits because of their positive effects on the product. In recent years the addition of oak chips has been used to introduce desirable wood aromas and flavours into wines. In this study, oak chips in saline solution or laboratory medium were inoculated with Penicillium purpurogenum, Aureobasidium pullulans, Phialemonium obovatum, Phanerochaete chrysosporium and a combination of Ph. chrysosporium and A. pullulans. After 12 weeks of incubation, oak chips (2 g L(-1)) were macerated in a red wine for 17 days. Gas chromatography/mass spectrometry and high-performance liquid chromatography were used to evaluate 14 compounds, namely furfural, furfuryl alcohol, guaiacol, syringol, cis-ß-methyl-γ-octalactone, 2-phenylethanol, 4-vinylguaiacol, benzyl alcohol, 2,3-butanediol, γ-butyrolactone, benzaldehyde, 4-ethylguaiacol, gallic acid and ellagic acid. RESULTS: The microfungal treatments increased the concentration of some components. In particular, P. purpurogenum resulted in a significant improvement in the levels of guaiacol, furfural, syringol, furfuryl alcohol and 2-phenylethanol. CONCLUSION: Penicillium purpurogenum and Ph. chrysosporium showed a constant trend (enrichment of furfural and benzaldehyde) independent to some extent of the medium used for chip treatment.

Influence of the production technology on kefir characteristics: Evaluation of microbiological aspects and profiling of phosphopeptides by LC-ESI-QTOF-MS/MS.

The influence of production technology, namely, temperature, pH and 2-step fermentation (back-slopping approach), on the microbiological characteristics and on the phosphopeptide profile of kefir obtained with kefir grains was investigated. The growth of yeasts, lactic acid bacteria (LAB) and acetic acetic bacteria (AAB) in both grains and kefir was affected by the incubation temperature and by the use of back-slopping. In particular, at 25 °C the microbiota of kefir grains was mainly composed by LAB and yeasts, while at 18 °C yeasts represented the dominant group in kefir. Back-slopping at 25 °C determined a significant increase of AAB. A comprehensive characterization of potentially bioactive peptides, including caseino-phosphopeptides (CPPs), was performed, for the first time, in kefir obtained with kefir grains, using preliminary enrichment on hydroxyapatite followed by dephosphorylation and analysis by Liquid Chromatography-ElectroSpray Ionization-Quadrupole-Time of Flight-tandem mass spectrometry (LC-ESI-QTOF-MS/MS). As a result, seventy-three phosphopeptides, mostly arising from caseins (79% ß-casein, 8% αs1-casein and 9% αs2-casein) and all including from three to five serine residues in their sequences, were identified. Seventy-one of them showed the typical motif "SerP-SerP-SerP-Glu-Glu", which is crucial for the ability of caseins to bind to minerals. Several peptides were observed, for the first time, from the 1-40 region of ß-casein. As for the effect of production technology, phosphopeptide profiles of kefirs obtained at 25 °C and 18 °C were very similar, whereas kefir produced under acidic conditions showed a predominance of smaller peptides, suggesting a higher level of proteolysis. Conversely, kefir obtained through back-slopping at 25 °C contained longer peptides, thus indicating a lower proteolytic activity and a poor reproducibility in the kefir phosphopeptide profile occurring when grains are reused.

Determination of choline in milk, milk powder, and soy lecithin hydrolysates by flow injection analysis and amperometric detection with a choline oxidase based biosensor.

A fast-response and interference-free amperometric biosensor based on choline oxidase immobilized onto an electropolymerized polypyrrole film for flow injection determination of choline in milk, milk powder, and soy lecithin hydrolysates is described. The sensor displayed an Imax value of 1.9 +/- 0.2 microA and an apparent Michaelis-Menten constant, k'M, equal to 1.75 +/- 0.07 mM. Detection limits of 0.12 microM could be obtained. Because even a slight deterioration of the anti-interference membrane can adversely affect measurement accuracy, a real time monitoring of the biosensor selectivity has been achieved by a dual Pt electrode flow-through cell where the enzyme modified electrode is coupled to an enzyme-free electrode in a parallel configuration. Finally, bracketing technique (alternate injections of sample and standards) allows a two-point calibration to be performed in real-time, correcting for any drift in sensor response.

Acaricide residues in laying hens naturally infested by red mite Dermanyssus gallinae.

In the poultry industry, control of the red mite D. gallinae primarily relies worldwide on acaricides registered for use in agriculture or for livestock, and those most widely used are carbamates, followed by amidines, pyrethroids and organophosphates. Due to the repeated use of acaricides--sometimes in high concentrations--to control infestation, red mites may become resistant, and acaricides may accumulate in chicken organs and tissues, and also in eggs. To highlight some situations of misuse/abuse of chemicals and of risk to human health, we investigated laying hens, destined to the slaughterhouse, for the presence of acaricide residues in their organs and tissues. We used 45 hens from which we collected a total of 225 samples from the following tissues and organs: skin, fat, liver, muscle, hearth, and kidney. In these samples we analyzed the residual contents of carbaryl and permethrin by LC-MS/MS.Ninety-one (40.4%) samples were positive to carbaryl and four samples (1.7%) were positive to permethrin. Concentrations of carbaryl exceeding the detection limit (0.005 ppm) were registered in the skin and fat of birds from two farms (p<0.01), although these concentrations remained below the maximum residue limit (MRLs) (0.05 ppm) (p<0.01). All organs/tissues of hens from a third farm were significantly more contaminated, with skin and muscle samples exceeding the MRL (0.05 ppm) (p<0.01) of carbaryl in force before its use was banned. Out of 45 chickens tested, 37 (82.2%) were found to be contaminated by carbaryl, and 4 (8.8%) by permethrin. The present study is the first report on the presence of pesticides banned by the EU (carbaryl) or not licensed for use (permethrin) in the organs and tissues of laying hens, which have been treated against red mites, and then slaughtered for human consumption at the end of their life cycle.

Verbascoside, isoverbascoside, and their derivatives recovered from olive mill wastewater as possible food antioxidants.

Olive oil processing industries generate substantial quantities of phenolic-rich byproducts, which could be valuable natural sources of antioxidants. This work is focused on the recovery and structural characterization of antioxidant compounds from olive mill wastewater (OMWW), a polluting byproduct of the olive oil production process. Phenolics were extracted from the waste material using a membrane technology coupled to low-pressure gel filtration chromatography on a Sephadex LH-20. The LH-20 fraction was, in turn, characterized for its phenolic composition by HPLC-DAD-MS/MS analyses. Verbascoside, isoverbascoside, ß-hydroxyverbascoside, ß-hydroxyisoverbascoside, and various oxidized phenolics were identified. Uptake of verbascoside, purified from the LH-20 fraction, by HT-29 cells, an established model system for studying drug transport properties, was also assayed. Finally, the antioxidant activities of the LH-20 fraction and verbascoside were characterized by two different techniques. Individual verbascoside was more active as a scavenger of reactive oxygen species and as a chemopreventive agent protecting low-density lipoproteins from oxidative damage than the LH-20 fraction.

Biological activity of high molecular weight phenolics from olive mill wastewater.

Olive oil production generates large amounts of recalcitrant compounds, the olive oil mill wastewater (OMWW), which represent one of the most contaminating effluents among those produced by the agrofood industries. Nowadays, this view has changed to one that recognizes the waste as a low-cost starting material rich in bioactive compounds, particularly biophenols, that can be extracted and applied as natural antioxidants for the food and pharmaceutical industries. The data reported in this paper indicate that the OMWW extracts, besides low molecular weight antioxidant phenolics such as tyrosol and hydroxytyrosol, also contain phenolics with a molecular weight in the range of 600-5000 Da, which exhibit efficient scavenging activities against hydroxyl and peroxyl radicals. This group of phenolics includes, besides verbascoside, isoverbascoside, and an oxidized form of verbascoside, a number of higher molecular weight phenolics arising from oxidative polymerization of hydroxytyrosol and caffeic acid. Overall, these higher molecular weight phenolics prove to be, in some in vitro tests, more efficient scavengers of hydrophilic hydroxyl radicals than hydroxytyrosol, which could be used for industrial applications as natural nontoxic antioxidants.

Rapid screening for anthocyanins and anthocyanin dimers in crude grape extracts by high performance liquid chromatography coupled with diode array detection and tandem mass spectrometry.

A rapid and efficient method using high performance liquid chromatography coupled with diode array detection and tandem mass spectrometry (HPLC-DAD-MS/MS) for fast screening large numbers of anthocyanins and anthocyanin dimers in different grape skin extracts, without further sample clean-up procedures, was developed. A good separation of most detected anthocyanins was achieved in a run time of 15 min. Identification of anthocyanin pigments required a combination of several information: UV-vis spectra, MS and MS/MS spectra, and elution pattern. Many compounds have been here detected for the first time and their structures tentatively elucidated.

Flow injection determination of choline in milk hydrolysates by an immobilized enzyme reactor coupled to a selective hydrogen peroxide amperometric sensor.

A choline oxidase (ChO) immobilized enzyme reactor (IMER) prepared by glutaraldehyde coupling of the enzyme on aminopropyl modified controlled pore glass beads is described. The ChO-IMER was coupled, in a flow injection configuration system, to an interference free hydrogen peroxide amperometric sensor based on a Pt surface modified by an overoxidized polypyrrole film. The resulting analytical device responds selectively to choline and displays a sensitivity of 46.9+/-0.2 microC mM(-1) and a limit of detection, calculated at a signal-to-noise ratio equal to 3, of 7 microM. Sensitivity remains constant for about 20 days and then starts to slowly deteriorate and after 2 months a 70% of the initial sensitivity was still retained. The application to choline determination in milk hydrolysates is demonstrated. Short- and long-term drift observed in the analytical response can be corrected by a bracketing technique.