Effect of the storage process on quality characteristics of hemp-enriched "tsoureki" a rich-dough baked Greek product.

The effects of the storage process on the quality characteristics of a hemp-enriched "tsoureki" (a rich-dough baked Greek product, rich-dough baked product [RDBP]) were investigated. The wheat flour was substituted with defatted hemp flour at selected ratios (0%-50% hemp:wheat flour). The baked products were stored at 25°C and at specific time intervals (0, 1, 4, 7, 10, and 14 days), and their properties were determined, including moisture content, water activity, structure, texture, color, total phenolic content (TPC), and antioxidant activity. Moreover, analyses of phenolic compounds were performed using quadrupole time of flight liquid chromatography-mass spectroscopy, identifying 14 compounds. Both the first-order kinetic model and modified Avrami equation, including the hemp-to-wheat ratio effect in the rate constant, well described the changes in the quality characteristics. The results showed that storage time and hemp incorporation significantly affected the quality of the product. Water activity decreased from 0.901 to 0.859, whereas moisture content decreased from 30.52%-32.33% (0 days) to 26.97%-27.02% w.b. (14 days) with storage time for all hemp additions. Hardness was greatly affected by hemp flour addition and approached 14.72 and 17.85 N after 14 days of storage for 30% and 50% substitutions, respectively. Springiness and cohesiveness decreased with hemp addition and storage time. The color difference of the hemp-enriched products compared to the control sample increased during storage. TPC increased due to the addition of hemp flour, whereas 14 compounds were identified. Based on property correlation, the hemp-enriched RDBP-tsoureki held its high-quality characteristics for 7 days of storage and contained a significant amount of bioactive compounds. PRACTICAL APPLICATION: Industrially produced, defatted hemp is a promising byproduct that can be used to nutritionally enhance baked goods. Modeling results can be used for the prediction of the properties that define product storage ability and also that the hemp-enriched, rich dough-baked Greek "tsoureki" could be produced while maintaining total phenolic content and antioxidant activity during 7 days of storage. These findings are expected to be used in the future in baked goods industry applications to produce goods with an improved nutritional profile.

On the Assessment of Strawberries' Shelf-Life and Quality, Based on Image Analysis, Physicochemical Methods, and Chemometrics.

The aim of the present study was to evaluate Marisol strawberries' (Fragaria × ananassa) physicochemical quality and shelf-life during storage, using an integrated analytical approach. More specifically, the research aimed to assess the strawberries' color, texture, and nutritional quality, over an 11-day storage period, employing physicochemical analyses, spectrophotometric assays, Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopy, image analysis, and statistical tools. The results revealed significant changes in the outer surface texture and color characteristics, indicating spoilage progression. Physicochemical parameters such as water activity, moisture content, soluble solids, titratable acidity, and ascorbic acid content exhibited significant alterations, influencing the taste profile and freshness perception. Antioxidant and antiradical activities showed fluctuations, suggesting a potential decrease in phenolic content during storage. Moreover, the ATR-FTIR spectra findings confirmed the results regarding the moisture content, soluble solids, and total phenolic content. The integration of physicochemical and image analysis-derived features through a principal component analysis (PCA) enabled the accurate classification of samples based on storage days. Regression analysis, using these features, successfully predicted the storage day with high accuracy. Overall, this integrated analytical approach provided valuable information on the estimation of Marisol strawberries' shelf-life and the prediction of their quality deterioration, contributing to better fruit management and the minimization of discards.

Optimization of Ultrasound-Assisted Extraction and Characterization of the Phenolic Compounds in Rose Distillation Side Streams Using Spectrophotometric Assays and High-Throughput Analytical Techniques.

Lately, the essential oils industry has been one of the most expanding markets globally. However, the byproducts generated after the distillation of aromatic plants and their transformation to novel high-added value products consist of a major up-to-date challenge. Thus, the scope of the current study is the optimization of ultrasound-assisted extraction (UAE) for the recovery of phenolic compounds from rose (Rosa damascena) post-distillation side streams using Box-Behnken design. In particular, the highest total phenolic content (TPC) was achieved at 71% v/v ethanol-water solution, at 25 min, 40 mL/g dry sample and 53% ultrasound power, while ethanol content and extraction time were the most crucial factors (p-value ≤ 0.05) for UAE. Both solid (RSB) and liquid (LSB) rose side streams exhibited significant antiradical and antioxidant activities. The interpretation of attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectra confirmed the presence of compounds with properties such as phenolic compounds, phenolic amide derivatives, and alcohols in the extracts. Moreover, the flavonoids naringenin, quercetin, and kaempferol were the major phenolic compounds, identified in the extracts by liquid chromatography-tandem mass spectrometry analysis (LC-MS/MS), followed by gallic, protocatechuic, p-hydroxybenzoic, and rosmarinic acids. Furthermore, the LC-MS/MS results pinpointed the effect of factors other than the extraction conditions (harvesting parameters, climatic conditions, plant growth stage, etc.) on the phenolic fingerprint of RSB extracts. Therefore, RSB extracts emerge as a promising alternative antioxidant agent in food products.

Quality Assessment of Ground Coffee Samples from Greek Market Using Various Instrumental Analytical Methods, In Silico Studies and Chemometrics.

Coffee is one of the most widely consumed beverages worldwide due to its sensory and potential health-related properties. In the present comparative study, a preparation known as Greek or Turkish coffee, made with different types/varieties of coffee, has been investigated for its physicochemical attributes (i.e., color), antioxidant/antiradical properties, phytochemical profile, and potential biological activities by combining high-throughput analytical techniques, such as infrared spectroscopy (ATR-FTIR), liquid chromatography-tandem mass spectrometry (LC-MS/MS), and in silico methodologies. The results of the current study revealed that roasting degree emerged as the most critical factor affecting these parameters. In particular, the L* color parameter and total phenolic content were higher in light-roasted coffees, while decaffeinated coffees contained more phenolics. The ATR-FTIR pinpointed caffeine, chlorogenic acid, diterpenes, and quinic esters as characteristic compounds in the studied coffees, while the LC-MS/MS analysis elucidated various tentative phytochemicals (i.e., phenolic acids, diterpenes, hydroxycinnamate, and fatty acids derivatives). Among them, chlorogenic and coumaric acids showed promising activity against human acetylcholinesterase and alpha-glucosidase enzymes based on molecular docking studies. Therefore, the outcomes of the current study provide a comprehensive overview of this kind of coffee preparation in terms of color parameters, antioxidant, antiradical and phytochemical profiling, as well as its putative bioactivity.

The Importance of Complementary PCR Analysis in Addition to Serological Testing for the Detection of Transmission Sources of Brucella spp. in Greek Ruminants.

The early and accurate diagnosis of brucellosis, a ubiquitous zoonotic infection, is significant in preventing disease transmission. This study aimed to assess the infection rate of Brucella spp. in ruminants and to evaluate the agreement between a serological test and a molecular method for the detection of infected cases. Blood and milk samples of 136 ruminants were analyzed using two laboratory methods: the Rose Bengal plate (RBP) test to detect B. abortus and B. melitensis antibodies and the molecular polymerase chain reaction (PCR) method for the presence of bacterial DNA. The agreement between the methods was assessed using the kappa statistic. Based on the RBP test, there were 12 (8.8%) seropositive animals (10 sheep and 2 cows), while 2 (1.4%) samples were positive on PCR analysis. The positive PCR samples were from seronegative cow samples on RBP testing. There was slight agreement (k = -0.02) between the two methods, which was not statistically significant. Our results indicate that complementary molecular methods are useful to detect the bacteria in infected animals that are seronegative due to an early stage of infection. Therefore, a combination of molecular methods and serological tests can be applied to detect brucellosis in ruminants efficiently.

Impact of tannin addition on the antioxidant activity and sensory character of Malagousia white wine.

Enological tannins are assessed as promising alternative to SO2 in order to control oxidative process during winemaking, due to allergic reactions incurred by sulfite sensitive individuals. In the present study, the commercial enological Tara tannin "Vitanil B″ was added, as alternative to the addition of sulfites, at different concentrations (100-500 mg/L) in white wine from grapes of Vitis vinifera L. var. Malagousia in order to enhance antioxidant stability and sensory character of the wine. Considering photometric analyses and chromatic parameters results, tannin addition (300 mg/L) in Malagousia enhanced total phenolic content, antioxidant and antiradical activity and prevented color deterioration, for a storage period of 100 d, compared to control and sulfited wines. Moreover, aroma quality, body, after taste and overall acceptance of wine treated with 300 mg/L tannin, were highly appreciated and received the highest scores. The overall evaluation of tannin addition was performed by Principal Component Analysis, leading to discrimination of wines, according to photometric, color and sensory analysis parameters. Conclusively, tannin addition resulted in a considerable increase of total phenolic content, antioxidant and antiradical activity, compared to the control and sulfited wines, maintaining the sensory parameters and overall acceptance of Malagousia wine.

Characterization of Bacterial Microbiota of P.D.O. Feta Cheese by 16S Metagenomic Analysis.

BACKGROUND: The identification of bacterial species in fermented PDO (protected designation of origin) cheese is important since they contribute significantly to the final organoleptic properties, the ripening process, the shelf life, the safety and the overall quality of cheese. METHODS: Ten commercial PDO feta cheeses from two geographic regions of Greece, Epirus and Thessaly, were analyzed by 16S metagenomic analysis. RESULTS: The biodiversity of all the tested feta cheese samples consisted of five phyla, 17 families, 38 genera and 59 bacterial species. The dominant phylum identified was Firmicutes (49% of the species), followed by Proteobacteria (39% of the species), Bacteroidetes (7% of the species), Actinobacteria (4% of the species) and Tenericutes (1% of the species). Streptococcaceae and Lactobacillaceae were the most abundant families, in which starter cultures of lactic acid bacteria (LAB) belonged, but also 21 nonstarter lactic acid bacteria (NSLAB) were identified. Both geographical areas showed a distinctive microbiota fingerprint, which was ultimately overlapped by the application of starter cultures. In the rare biosphere of the feta cheese, Zobellella taiwanensis and Vibrio diazotrophicus, two Gram-negative bacteria which were not previously reported in dairy samples, were identified. CONCLUSIONS: The application of high-throughput DNA sequencing may provide a detailed microbial profile of commercial feta cheese produced with pasteurized milk.

Association of TNF-α 308G/A and LEPR Gln223Arg Polymorphisms with the Risk of Type 2 Diabetes Mellitus.

The objective of the present study was to identify the association of the TNF-α- 308G/A and leptin receptor (LEPR) Gln223Arg polymorphisms with the risk of development of type 2 diabetes mellitus (T2DM). METHODS: A total of 160 volunteers were studied: 108 with T2DM and 52 participants as control, who served as the control group. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for the genomic region of TNF-α- 308G/A and LEPR Gln223Arg were carried out. RESULTS: The frequency of LEPR Gln223Arg genotypes in T2DM and control groups showed significant differences in the distribution of genotypes (p < 0.05). The frequency also of TNF-α- 308G/A genotypes in T2DM and control subjects showed significant differences in the distribution of genotypes (p < 0.05). CONCLUSION: Our results indicate that there are significant differences in the distribution of genotypes and alleles between the individuals with T2DM and control subjects (p < 0.05).

Effects of Infrared Radiation on Eggplant (Solanum melongena L.) Greenhouse Cultivation and Fruits' Phenolic Profile.

The implementation of Infrared (IR) radiation in heated greenhouses possesses the advantage of high directional control and focused compensation of energy losses, appropriate for creating local microclimate conditions in highly energy-consuming systems, such as greenhouses. Moreover, it can efficiently maintain favorable environmental conditions at the plant canopy. The present study studies the application of Infrared (IR) heating in an experimental greenhouse with eggplant (Solanum melongena L.) cultivation. The experimental results are presented from a full cultivation period inside two identical, small scale experimental greenhouses, with IR and forced air heating system, respectively. The effects of IR heating over plant growth parameters, including the yield of the fruits as well as the total phenolic content and the antioxidant profile of eggplants fruits' extracts are measured and discussed. The results indicate a greater uniformity production in the IR heating greenhouse in terms of antioxidant and radical scavenging activities, as well as the total phenolic content. Moreover, the phenolic profile of eggplant fruits from both greenhouses revealed the existence of numerous bioactive compounds, some of which were only characteristic of the eggplant fruits from IR heated greenhouses.

Evaluating the experimental cultivation of peppers in low-energy-demand greenhouses. An interdisciplinary study.

BACKGROUND: Photovoltaics (PV) provide an alternative solution to cover energy demands in greenhouses. This study evaluates the effect of PV panels installed on the roofs of greenhouses, and the partial shading that they cause, on the growth parameters and growth indicators of the experimental cultivation of peppers (Capsicum annuum cv. California Wonder). The growth of the plants, the antioxidant profile, radical scavenging activity, total phenolic content, and the phenolic and metabolic profiles (using LC-MS spectrometry and NMR spectroscopy) are evaluated. RESULTS: Data are presented from a full cultivation period. Results indicated that indoor temperatures were similar for both glass and glass-PV (glass with PV panels installed) greenhouses during the day and the night. The production yield was higher for the glass-PV greenhouses. The pepper fruits' weight, dimensions, and thickness were similar in both cases. Comparison of the pepper fruit extracts in terms of total phenolic content, antioxidant, and antiradical activities indicated differences that were not statistically significant. Photometric and spectroscopic studies both showed a smaller distribution of values in the case of the glass-PV greenhouse, probably indicating a more consistent phytochemical profile. CONCLUSION: Covering only a small proportion (ca. 20%) of the greenhouse roof with photovoltaic panels contributes considerably to its energy demands without affecting plant growth and quality. © 2018 Society of Chemical Industry.

On the Characterization and Correlation of Compositional, Antioxidant and Colour Profile of Common and Balsamic Vinegars.

Commercially available common and balsamic vinegars were examined, using a combination of spectrophotometric, chromatographic, colorimetric and spectroscopic methods. Total phenolic content, antioxidant activity, radical scavenging capacity, phenolic profile, colour parameters, Fourier Transform Infrared (FT-IR) absorbance spectra and Nuclear Magnetic Resonance (¹H NMR) spectra were comparatively studied. The main scope was the assessment of vinegar antioxidant and metabolic profiles and the identification of the most appropriate features influencing their type and subtypes. Red grape balsamic vinegars exhibited the strongest antioxidant profile. High total phenolic content and radical scavenging-antioxidant activity of vinegars was strongly correlated with high hue-angle and colour density values and low lightness and a* values. FT-IR spectra analysis confirmed the presence of organic acids and carbohydrates and, in combination with Gas Chromatography-Mass Spectrometry (GC-MS), the occurrence of phenolic compounds. NMR spectroscopy enabled the identification of 27 characteristic metabolites in each type of vinegar. The combination of all applied techniques provides critical information on compositional differences among the vinegars and could serve as an application tool for similar fermentation products.

Optimization of Polyphenol Extraction from Allium ampeloprasum var. porrum through Response Surface Methodology.

Allium ampeloprasum var. porrum has been recognized as a rich source of secondary metabolites, including phenolic acids, flavonoids and flavonoid polymers (proanthocyanidins or condensed tannins), with related health benefits. Both parts of Allium ampeloprasum var. porrum (white bulb and pseudostem) are traditionally consumed either as a vegetable or as a condiment in many Mediterranean countries. The aim of the present study was to optimize the extraction conditions of polyphenols from white leek stem and green leek leaf by implementing a Box-Behnken design (BBD). The optimization considered basic factors affecting extraction efficiency, including extraction time, solvent to plant material ratio and solvent mixture composition. Maximum polyphenol yield was achieved at an extraction time of 80 and 100 min for white leek stem and green leek leaf extracts respectively, solvent to plant material ratio of 5:1 (v/w) and methanol to water ratio of 40:60 (v/v), for both leek extracts. Interestingly, higher total phenolic content was found in green leek leaf extracts compared to white leek stem extracts, due to a possible relationship between polyphenol production and sunlight radiation. High correlation values were also observed between total phenolic content and antioxidant-antiradical activity of optimized leek extracts.

Herbal distillates: A new era of grape marc distillates with enriched antioxidant profile.

Grape marc distillates are traditional alcoholic beverages, produced mostly in the Mediterranean countries. The present study proposes the enrichment of a Greek traditional grape marc distillate (tsikoudia) with selected herbs to enhance its natural antioxidants and functional properties. Total phenolic content, the antiradical and antioxidant activities, as well as the phenolic and sugar profiles using NMR and FT-IR spectroscopy were evaluated. The enrichment of distillates with Syzygium aromaticum L., Jasminum officinale L. and Eucalyptus globulus Labill. exhibited the highest total phenolic content as well as the highest antioxidant and antiradical activities, whereas the lowest values were observed with Hippophae rhamnoides L. and Lycium Barbarum Mill. The implementation of NMR and FT-IR spectroscopies attested to the presence of phenolic compounds and of specific carbohydrates in herbal distillates, postulating their migration from selected herbal species to tsikoudia and probably contributing to their organoleptic characteristics. The target of this approach leads to new added-value distillates with enhanced characteristics.

Metabolic and antioxidant profiles of herbal infusions and decoctions.

This study implements NMR metabolomics and spectrophotometric studies (Folin-Ciocalteu, FRAP, ABTS) to infusions and decoctions of ten plant species in order to assess and compare the metabolic and antioxidant profiles for each botanical family. Multivariate and univariate data analyses highlighted the differences among the samples and pinpointed specific classes of compounds for each plant species as well as infusions and decoctions. The identified phenolic compounds by NMR, as well as the antioxidant profile, framed a trend of increased values in infusions compared to the decoctions. Moreover, the infusion procedure positively affected the extractability of the phenolic compounds compared to decoctions. The highest total phenolic content was found in Mentha spicata, while the lowest in Matricaria chamomilla preparations, irrespective of the preparation method. The preparation time for the decoctions was examined showing that the 15min preparations were generally found richer in phenolics and of higher antioxidant capacity.

Carotenoids from Foods of Plant, Animal and Marine Origin: An Efficient HPLC-DAD Separation Method.

Carotenoids are important antioxidant compounds, present in many foods of plant, animal and marine origin. The aim of the present study was to describe the carotenoid composition of tomato waste, prawn muscle and cephalothorax and avian (duck and goose) egg yolks through the use of a modified gradient elution HPLC method with a C30 reversed-phase column for the efficient separation and analysis of carotenoids and their cis-isomers. Elution time was reduced from 60 to 45 min without affecting the separation efficiency. All-trans lycopene predominated in tomato waste, followed by all-trans-ß-carotene, 13-cis-lutein and all-trans lutein, while minor amounts of 9-cis-lutein, 13-cis-ß-carotene and 9-cis-ß-carotene were also detected. Considering the above findings, tomato waste is confirmed to be an excellent source of recovering carotenoids, especially all-trans lycopene, for commercial use. Xanthophylls were the major carotenoids of avian egg yolks, all-trans lutein and all-trans zeaxanthin in duck and goose egg yolk, respectively. In the Penaeus kerathurus prawn, several carotenoids (zeaxanthin, all-trans-lutein, canthaxanthin, cryptoxanthin, optical and geometrical astaxanthin isomers) were identified in considerable amounts by the same method. A major advantage of this HPLC method was the efficient separation of carotenoids and their cis-isomers, originating from a wide range of matrices.

Process optimisation for recovery of carotenoids from tomato waste.

Carotenoids constitute an important component of waste originating from tomato processing plants. Studies were carried out to assess the extraction yield of tomato waste carotenoids in different solvents and solvent mixtures and to optimise the extraction conditions for maximum recovery. A mixture of ethyl acetate and hexane gave the highest carotenoid extraction yield among the others examined. Extraction conditions, such as percentage of hexane in the solvent mixture of ethyl acetate and hexane, ratio of solvent to waste and particle size were optimised using a statistically designed experiment. A regression equation for predicting the carotenoid yield as a function of three extraction variables was derived by statistical analysis and a model with predictive ability of 0.97 was obtained. The optimised conditions for maximum carotenoid yield (37.5mgkg(-1)drywaste) were 45% hexane in solvent mixture, solvent mixture to waste ratio of 9.1:1 (v/w) and particle size 0.56mm.