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Fermented products with a pleasant aroma and with strong honey, rose, and fruit odor notes were developed through the biotransformation of a medium containing sour or sweet whey with the addition of l-phenylalanine by the Galactomyces geotrichum mold. In order to obtain the strong honey-rose aroma, G. geotrichum strains were screened and fermentation conditions were optimized to achieve a preferable ratio (>1) of phenylacetaldehyde to 2-phenylethanol by the Ehrlich pathway. This allowed post-fermentation products with the ratio of concentrations of phenylacetaldehyde to 2-phenylethanol being 1.7:1. Additionally, the use of gas chromatography-olfactometry (GC-O) analysis and the calculation of odor activity values (OAVs) allowed 10 key odorants to be identified in post-fermentation products. The highest OAVs were found for phenylacetaldehyde with a honey odor in both sour and sweet whey cultures (3010 and 1776, respectively). In the variant with sour whey, the following compounds with the highest OAVs were 3-methyl-1-butanol (131), 3-(methylthio)-propanal (119), 3-methylbutanal (90), dimethyl trisulfide (71), 2,3-butanedione (37), and 2-phenylethanol (29). In the post-fermentation product with sweet whey, the following compounds with the highest OAVs were 3-(methylthio)-propanal (112), dimethyl trisulfide (69), and 2,3-butanedione (41).

Currently, there is a growing demand for flavorings, especially of natural origin. It is worth paying attention to the biotechnological processes of flavor production, characterized by simplicity, high efficiency and relatively low cost. In this study, we analyzed the ability of the Galac tomyces geotrichum mold to transform by-products of the dairy industry: sour whey and buttermilk to complex flavour mixtures with pleasant, honey-rose aroma. Furthermore, the aroma complexity of the fermentation product has been carefully identified applying a sensomic approach involving the use of gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS) and stable isotope dilution assay (SIDA) to identify and quantify aroma compounds. Based on the calculation of odor activity value (OAV), 13 key aroma compounds were present in both tested variants. The highest OAVs were found for phenylacetaldehyde (honey-like) in the buttermilk variant (912) and 2-phenylethanol (rose-like) in the sour whey variant (524). High values of this indicator were also recorded for phenylacetaldehyde (319) and 3-methyl-1-butanol with a fruity aroma (149) in the sour whey culture. The other compounds identified are 3-methylbutanal (malty), 2,3-butanedione (cheesy), isovaleric acid (cheesy), 3-(methylthio)-propanal (boiled potato), butanoic acid (vinegar), (E)-2-nonenal (fatty), ethyl furaneol (burnt sugar), dimethyl trisulfide (cabbage), and acetic acid (vinegar).

Pseudomonas aeruginosa is a common contaminant in fish-based products. Given the resistance of P. aeruginosa to synthetic preservatives, there is a need for novel tools to suppress the growth and virulence of this pathogen. This study investigated the potential of β-caryophyllene-rich green pepper essential oil (EO) as a biopreservative agent against the wild type KM01 strain of P. aeruginosa. Green pepper EO at selected concentration was non-toxic to FHs 74 Int and CCD 841 CoN human cell lines, as determined with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The sub-minimal inhibitory concentrations (MICs) of green pepper EO and β-caryophyllene were 120 and 25 nl ml−1, respectively; exposure of P. aeruginosa KM01 to these concentrations increased unsaturated fatty acids (FAs) (especially C16:1 cis-9 and C18:2 cis-9,12) and decreased saturated and hydroxylated FAs (especially 16:0, 3-OH-12:0, and 2-OH-16:0) in the bacterial cell membrane. An absence of anteiso-C15:0 synthesis was also observed in membrane FA profiles. The results of modeling and in situ experiments revealed that green pepper EO and β-caryophyllene inhibited the growth of KM01 (by 89%–95%) and attenuated bacterial virulence properties such as pyocyanin production (by 80%–89%) and elastase (by 40%–72%) and alkaline protease (by 28%–91%) activities.

Plant essential oils have bacteriostatic activity in very low concentrations, thus they can be used as natural preservative in food products. The aim of this work was to understand the inhibitory and non-bactericidal effects of essential oils in low concentrations. To meet this aim some physical and biochemical properties of two P. orientalis strains isolated from food probes were investigated under the influence of plant oils. Control probes - without oils - played an important role in our investigations because P. orientalis is not a well-known and described species. Thus, these results allow us to gain additional knowledge about bacteria from P. orientalis species. The obtained results are proof that under the influence of oils, bacteria lose their ability to move, change their morphology, and also reduce their metabolic activity. However, they do not die, and properties such as the ability to produce ammonia, the ability to production of indole from the amino acid tryptophan as well as the ability to assimilation of saccharides are maintained.

Key odorants of peated single malt whisky were identified using gas chromatography – olfactometry (GC-O). Twenty compounds were identified with FD (Flavor Dilution) values ranging from 8 to 2048 and 8 of them were volatile phenols. The compounds with the highest FD were 2-methoxyphenol (guaiacol), 4-ethyl-2-methoxyphenol (4-ethylguaiacol), 4-methylphenol, 4-vinyl-2-methoxyphenol (4-vinylguaiacol) and 4-ethyl-2-methylphenol (FD ranging from 512 to 2048). Then odorants were used successfully to distinguish peated single malts from 3 other whisky types (mild single malts, blended and American whiskies) based on PCA followed by LDA applied to GC×GC-ToF MS data of volatiles extracted using SPME. 36 whiskies representing all groups were used for the differentiation experiments. Finally, 61 volatile compounds based on Fisher ratios were selected to fully discriminate between 4 whisky types based on profile of volatiles obtained in SPME-GC×GC-ToF MS analysis. Cross-validation confirmed the suitability of PCA and LDA models for the discrimination of different whisky types.

In this study, varying concentrations of polyunsaturated fatty acids in goat’s milk were obtained by supplementing goat feed rations with maize dried distillers grains with solubles (DDGS). In comparison to the control group, the milk of goats that received DDGS contained about 25% more polyunsaturated fatty acids, 30% more conjugated linoleic acid (CLA), and had more favorable values of the atherogenic and thrombogenic indices. The diverse composition of fatty acids present in the goat’s milk correlated with the olfactory perception of the milk and its volatile compound profile. The level of unsaturated fatty acids significantly affected the odors detected in the processed goat’s milk. The volatile compound profile of the milk was mostly differentiated by the concentrations of aldehydes (hexanal and furfural) and furanones (furaneol), which exceeded their odor threshold values. The total concentration of identified aldehydes was highest in pasteurized milk samples from the goats of the experimental group, as a result of heating. Furfural was found in pasteurized samples of both the control and experimental milk at concentrations exceeding its odor threshold (3 mg·kg−1). Feeding goats with DDGS did not change the animal, cooked, dairy fat, lack of freshness, light-oxidized, or overall dairy flavors of the raw milk. After pasteurization, milk from goats fed with DDGS retained its characteristic animal odor and gained a very intense cooked flavor.

Aroma-active compounds in the roasted leg meat of White Koluda goose were assayed by gas chromatography-olfactometry, using aroma extract dilution analysis and solvent-assisted flavor evaporation. Quantitation, recombination-omission tests, and sensory evaluation were carried out. Thirty aroma compounds, for which odor activity values (OAVs) were calculated and for which the flavor dilution factors were greater than or equal to 1, were identified. The concentration of aroma compounds ranged from 0.06 to 633 (μg/kg). The highest OAVs (>1024) were for 2-furfurylthiol, 2-acetyl-1-pyrroline, and 1-octen-3-one. Nine key aroma compounds were: 2-furfurylthiol, 2-acetyl-2-thiazoline, 1-octen-3-one, 2-phenylethanethiol, 4,5-dimethyl-3-hydroxy-2(5H)-furanone, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, (E,E)-2,4-decadienal, 2-acetyl-1-pyrroline, and 3-(methylthio)propanal. The intensity of the dominating roasted, meaty/broth, and fatty notes in the recombination model consisting of the key odorants were rated (10-point scale) at 4.6-5.8 points, relative to the original roasted goose (5.2-6.2). The aroma compounds defined predominantly the meaty, roasted, and fatty flavors during the descriptive sensory evaluation of the roasted goose meat.

Background Non-diary beverages with probiotic properties are of great interest nowadays. In this research, we evaluated the suitability of carob kibbles in the manufacture of kvass. Kvass is a low-alcohol drink popular in Central and Eastern Europe and indicated as a potential non-diary beverage with probiotic properties. Therefore, the viability of probiotic strains of Lactobacillus plantarum and Saccharomyces boulardii during 4 weeks' storage in manufactured beverages was tested. Results Carob kibbles introduced significant amounts of phenolic compounds into kvasses, especially gallic acid (up to 117.45 ± 10.56 mg L-1 ), and improved antiradical activity up to 78% after fermentation. Moreover, fermentation efficiently reduced furfural and hydroxymethylfurfural content in samples up to 12.9% and 29.9%, respectively. Kvasses with rye malt extract possessed coffee-like, chocolate-like, roasted and caramel-like odours and a more bitter taste. Whereas kvass with carob kibbles was characterized by fruit-like odour and sweeter taste. Fermentation contributed to a creation as well as degradation of volatiles. L. plantarum exhibited higher general mortality during storage, whereas, in the case of S. boulardii, the viability was significantly higher regardless of the sample composition. Conclusion This is the first study reporting the use of carob kibbles for kvass production. The obtained results showed that carob kibbles can replace rye malt extract, at least partially, in the production of kvass, giving to the product added health benefits. Moreover, S. boulardii is a better choice for production of kvass with probiotic properties. © 2021 Society of Chemical Industry.

Abstract The present study aimed to elucidate the effect of subinhibitory concentrations (sub-MICs) of juniper essential oil (EO), α-pinene, and sabinene on the quorum-sensing (QS)–mediated proteolytic and lipolytic properties of Pseudomonas fluorescens KM24. These activities were verified under in situ conditions, in which sub-MICs of the agents altered the morphology of KM24 cells. RNA-Seq studies revealed key coding sequences (CDSs)/genes related to QS and the proteolytic/lipolytic activities of pseudomonads. In this work, all the examined agents decreased autoinducer synthesis and influenced the mRNA expression of the encoding acyltransferase genes lptA, lptD, and plsB. The highest reduction on the 3rd and 5th days of cultivation was observed for the genes lptD (−5.5 and −5.61, respectively) and lptA (−3.5 and −4.0, respectively) following treatment with EO. Inhibition of the lptA, lptD, and plsB genes by singular constituents of EO was on average, from −0.4 to −0.7. At 5 days of cultivation the profile of AHLs of the reference P. fluorescens KM24 strain consisted of 3-oxo-C14-HSL, 3-oxo-C6-HSL, C4-HSL, and N-[(RS)-3-hydroxybutyryl]-HSL, the concentrations of which were 0.570, 0.018, 3.744, and 0.554 μg ml−1, respectively. Independent of the incubation time, EO, α-pinene, and sabinene also suppressed the protease genes prlC (−1.5, −0.5, and −0.5, respectively) and ctpB (−1.5, −0.7, and −0.4, respectively). Lipolysis and transcription of the lipA/lipB genes were downregulated by the agents on average from −0.3 to −0.6. α-Pinene- and sabinene-rich juniper EO acts as an anti-quorum-sensing agent and can repress the spoilage phenotype of pseudomonads. Key points: Juniper EO, α-pinene, sabinene exhibited anti-QS potential toward KM24. RNA-Seq revealed key CDSs/genes related to QS/proteolytic/lipolytic activities of KM24. Agents at sub-MIC levels influenced the mRNA expression of QS/lipase/protease genes.

This study provides important information about the impacts of various levels of oat (OBG) and bacterial (curdlan) &beta, glucan and fat contents in milk on survivability and metabolism of yogurt starter cultures. The results show that addition of &beta, glucans in the concentration higher than 0.25% reduced starter bacterial counts during storage and prolonged the milk acidification process. A significant increase in lactose consumption by starter cultures was noted in the yogurt samples with OBG addition up to 0.75%. The highest (by 567% on average) increase in lactic acid content was noted in the control yogurts. Whereas the lowest (by 351%) increase in lactic acid content was noted in yogurts with OBG. After 28-day storage, the acetic aldehyde content was significantly influenced by fat content, type and addition level of polysaccharide. A higher increase in acetoin content was noted in samples with 0.25% than in samples with 1% of polysaccharides. In turn, significantly lower increases in diacetyl and 2,3-pentanedione contents were observed in the yogurt samples with OBG than in these with curdlan, with diacetyl production increase along with the higher concentration of the polysaccharide. The addition of OBG and curdlan to milk contributed to differences in the starter culture metabolism, consequently, in the milk acidification dynamics.

Food safety is a fundamental concern of consumers, regulatory agencies, and the food industry. Increasing the morbidity of foodborne diseases, coupled with economic implications, makes continual efforts for safer foods production and developing new antimicrobial agents necessary. The alternatives to chemical preservatives are natural ones that are nontoxic, such as pepper. Pepper essential oils can be used both as flavor improvement agents and as efficient preservatives of food products. The present review attempts to provide an overview of the most bioactive ingredients of pepper essential oils and to describe their mode of hypothetical antimicrobial action. We examined data from the literature to understand the complex mechanism of interaction between bioactive compounds of pepper and microbes. The novel application possibilities of pepper oils in food technology, especially in meat, fish, and vegetable processing, were also described.

Given the increasing consumption of aquatic foods and green consumerism, efficient methods for extending the shelf-life and maintaining the safety of seafood are urgently required. The present study aimed to evaluate the effect of black pepper essential oil (BPEO) and its major compounds – limonene (LIM) and beta-caryophyllene (CAR) on quorum sensing (QS) and efflux pump (EP) systems in Pseudomonas psychrophila KM02. Transcriptomic analysis was performed to select antimicrobial resistance genes that were only truly expressed within the system mimicking the food matrices. Compounds analyzed at subinhibitory concentrations (subMICs) (135, 65 and 35 μL/mL) reduced QS autoinducer synthesis to levels lower than the limit of detection and decreased proteolytic activity and exopolysaccharide synthesis by 35, 29 and 28%, and by 58, 32 and 41%, respectively. These phenotypic results were confirmed by changes in the ratio of expression of selected genes. Furthermore, the anti-QS activity and anti-EP of LIM and CAR were evaluated by molecular docking analyses with QS receptor proteins (LasR, RhlR, TraR, and PqsR) and inner membrane EP proteins (MuxB, MexB, and Mfs). The mRNA transcript levels of membrane fusion and outer membrane proteins, and transcription of repressor regulators MarR and TetR were considerable decreased. Our work showed that BPEO major compounds affected the functioning of the QS and EP system in KM02 and consequently reduced the spoilage potential.

Pseudomonas fluorescens are able to cause the biodeterioration process of fresh-cut lettuce via the indole-3-acetic acid (IAA)-dependent type III secretion system (TTSS). The application of pepper EOs of proven of anti-IAA and anti-TTSS activities into salad dressing can reduce the organoleptic deterioration of fresh-cut leafy vegetables during storage. In this work, the influence of black and white pepper EOs on IAA production and on TTSS gene expression in P. fluorescens KM06 was examined. The black and white pepper EOs and β-caryophyllene at concentrations below the sub-MICs altered (i.e., 78%, 94%, and 90%, respectively) the IAA production in a 72 h old culture of P. fluorescens KM06. All the test agents significantly reduced the mRNA levels of the TTSS gene (−0.106, −0.428, and −0.448 for black pepper EO, white pepper EO and β-caryophyllene, respectively) (p

Essential oils can be used as preservatives in foods because of their ability to inhibit bacteria growth in low concentration, which does not influence on foods’ organoleptic properties and does not generate the resistance mechanisms in cells. The aim of that work was to compare the effectiveness of commercial oils from black pepper (Piper nigrum), rosemary (Rosmarinus officinalis), lemongrass (Cymbopogon citratus) and juniper (Juniperus communis L.) with oils obtained in our laboratory. The typical cultivation method was supported by the flow cytometry to detect the cells of very low physiologic and metabolic activity. Our investigation demonstrated that both types of oils can effectively inhibit the growth of saprophytic bacteria P. orientalis. The oils distilled in our laboratory had a bacteriostatic effect at a lower concentration, which is important for application in the food industry. Flow cytometry analyzes and confirmed the thesis that essential oils do not have a germicidal effect on bacteria cells.

Some species of gut bacteria produce short-chain fatty acids (SCFAs) from dietary fiber—mainly acetate, propionate, and butyrate. The composition of human gut microbiota is dependent on dietary intake and health status. The aim of this study was to assess the effect of diet and anthropometric parameters on the potential of gut microbiota to metabolize dietary fiber and produce SCFA.A group of 200 men and women aged 31 to 50 years old participated in the study. The diet was assessed using three-day dietary records and the dietary pattern was determined using score methods. The potential to utilize water-insoluble fiber was assessed by measuring the β-glucosidase enzymatic activity of dissolved feces. To estimate the potential to metabolize water-soluble dietary fiber, cultures containing feces and pectin were incubated under anaerobic conditions for 24 hours. The amounts of fiber, acetic acid, propionic acid, and butyric acid before and after incubation were measured.Pectin utilization correlated positively with the amount of energy intake from fat (r = 0.19) and with the intake of nuts and seeds (r = 0.17) and was negatively correlated with the amount of energy from complex carbohydrates (r = -0.16) and its sources, such as refined grain products (r = -0.15). The dietary pattern did not affect the potential of the gut microbiota to metabolize pectin, but did influence the potential to digest insoluble dietary fiber, as the subjects following the western dietary pattern had lower potential than those following the rational pattern. β-glucosidase activity correlated positively with the intake of dietary fiber (r = 0.19) and intake of its sources, such as fruits (r = 0.18), vegetables (r = 0.21), and nuts and seeds (r = 0.18); it correlated negatively with nonalcoholic beverage intake (r = -0.15) and sugar and honey intake (r = -0.16). The potential to synthesize acetic acid correlated negatively with dietary indices and dietary fiber intake (r = -0.18). The potential to synthesize propionic acid correlated negatively with hip and waist circumference (r = -0.14, -0.15, respectively). The potentials to synthesize both propionic and butyric acid were affected by the intake of nuts and seeds (r = 0.18, 0.21, respectively).Diet affects the potential of gut microbiota to utilize dietary fiber and to produce SCFAs. The impact of anthropometry parameters was only seen on the potential to synthesize propionic acid.

The volatiles of cape gooseberry fruit (Physalis peruviana L.) were isolated by solvent-assisted flavor evaporation (SAFE), odor active compounds identified by gas chromatography&ndash, olfactometry (GC-O) and gas chromatography&ndash, mass spectrometry (GC-MS). Quantitation of compounds was performed by headspace&mdash, solid phase microextraction (HS-SPME) for all but one. Aroma extract dilution analysis (AEDA) revealed 18 odor active regions, with the highest flavor dilution values (FD = 512) noted for ethyl butanoate and 4-hydroxy-2,5-dimethylfuran-3-one (furaneol). Odor activity values were determined for all 18 compounds and the highest was noted for ethyl butanoate (OAV = 504), followed by linalool, (E)-non-2-enal, (2E,6Z)-nona-2,6-dienal, hexanal, ethyl octanoate, ethyl hexanoate, butane-2,3-dione, and 2-methylpropanal. The main groups of odor active compounds in Physalis peruviana L. were esters and aldehydes. A recombinant experiment confirmed the identification and quantitative results.

Application of gas chromatography-olfactometry (GC-O) analysis to pumpernickel bread and its intermediate products obtained during the fermentative process allowed for the recognition of 32 key aroma compounds with specific odor notes. Subsequent quantitation using the stable isotope dilution assay (SIDA) and calculation of odor activity values (OAVs) revealed 22 compounds with OAV1, with the highest OAV for 3-methylbutanal with a malty odor (6660), 2-methylbutanal with a malty odor (4560), 3-(methylthio)propanal with a boiled potato odor (2047), 3-hydroxy-4,5-dimethyl-2(5

Application of gas chromatography-olfactometry (GC-O) carried out on the volatile fraction isolated by solvent-assisted flavor evaporation (SAFE) and solid phase microextraction (SPME) from Lazur mold-ripened cheese revealed 17 odor-active compounds. The highest flavor dilution factor (FD) has been obtained for methanethiol (2048) with a burnt odor note and for 2(3)-methylbutanoic acid (2048) with a cheesy, pungent odor. Further quantitation of the 15 most aroma-active compounds allowed for calculation of their odor activity values (OAV). The highest OAVs were obtained for methanethiol (500), 3(2)-methylbutanoic acid (321), 3-(methylthio)propanal (210), 2,3-butanedione (65), dimethyl trisulfide (22), butanoic acid (20), 1-octen-3-ol (18), ( Z)-4-heptenal (14), dimethyl disulfide (14), dimethyl sulfide (13), phenylacetaldehyde (6), 2-ethyl-3,5-dimethylpyrazine (5), and acetic acid (4). An aroma recombination experiment showed slight differences in the perception of cheesy/sweaty and moldy/musty notes. To verify the influence of methyl ketones on the aroma profile of mold-ripened cheese, recombinant has been additionally supplemented with 2-pentanone, 2-heptanone, and 2-nonanone in concentrations determined in Lazur cheese. The aroma profile remained unchanged, which would suggest that methyl ketones, in this particular cheese, do not play a significant role in the formation of aroma.

The aim of the study was to produce fermented ewe’s milk with an increased ratio of native whey proteins and to characterize selected properties (metabolic activity, mono- and disaccharides, lactic acid and ethanol content, aroma profile, texture, color and sensory properties) of experimental milk and final product. Increasing the ratio of whey proteins to caseins in experimental milk resulted in higher activity of microorganisms belonging to the starter culture used in fermentation and higher content of volatile ketones in total volatile compounds identified during experiment. Increase in the lactic acid content and brightness parameter in fermented milk was observed in product made from experimental milk with modified ratio of whey proteins to caseins. It was concluded that changing the ratio of the main protein fractions in experimental milk differences in the physical and chemical properties of the final product, but these changes did not have a negative influence on sensory properties and product desirability.

The purpose of these investigations was to evaluate the anti- quorum sensing and anti-biofilm potential of Thymus vulgare essential oil (EO) and its respective components. The behavior of the agents tested was validated via examination of their influence on the production of quorum sensing autoinductors (AHLs), motility, flagella ( flgA ) gene expression, and biofilm formation capacity by model Pseudomonas fluorescens KM121 strain. In this work, Thymus vulgare EO, carvacrol, and thymol at concentrations below the sub-MICs caused significant limitations (i.e., 90%, 80% and 78%, respectively) in the AHLs production in a 72-h-old P . fluorescens KM121 culture. All of the tested agents, which were appreciably effective against P . fluorescens KM121 AHLs production, significantly suppressed bacterial motility and reduced the mRNA level of flagella gene (−0.672, −0.776, and −0.576 for thyme EO, carvacrol and thymol, respectively). Changes in the expression of the AHL-related flgA gene significantly inhibited the biofilm formation on stainless-steel (type 316L) surfaces and only single bacterial cells were presented on the surfaces. The results of the present study propose Thymus vulgare EO as a candidate biocide against food-spoilage P . fluorescens biofilms.

The present study aimed to evaluate the anti-quorum sensing (anti-QS) and anti-proteolytic potentials of tarragon essential oil (TEO) and its major compounds against food-associated Pseudomonas spp. The activities were verified by in vitro, in silico and in situ approaches. In this work, methyl eugenol (ME)- and β-phellandrene (β-PH)-rich TEO was investigated. TEO at subMIC increased the percentage of saturated fatty acids in the bacterial membranes (from 7 to 22%) and exhibited anti-quorum sensing via decreasing the efficiency of QS autoinducer synthesis [3-oxo-C12-HSL (from 2.028 μg/mL toLOD), C4-HSL (from 1.312 μg/mL toLOD) and PQS (from 0.007625 μg/mL toLOD)]. ME and β-PH were docked into LasR, RhlR and PqsR proteins, with docking scores comparable to native autoinductors. The subMICs of TEO, ME and β-PH decreased the proteolysis in the examined bacteria by 33, 29, and 21% (in TSB medium) and by 29, 26, and 19% (in fish juice medium), respectively. Almost all genes encoding proteases were downregulated by the applied agents. The ME- and β-PH-rich TEO acts as an anti-QS agent and significantly suppresses the proteolytic activity of food-associated pseudomonads. It might therefore increase the quality of fish-based products, where Pseudomonas spp. predominate.

The purpose of this work was to evaluate the anti-proliferative and anti-quorum sensing potential of Myrtus communis L. essential oil (EO). The biopreservative attributes of EO were also determined after introduction of the oil into a chitosan-based nanomatrix. Myrtle EO concentrations ranging from 76 nl ml−1 to 500 nl ml−1 were cytotoxic against colon cancer HT-29 and liver cancer HepG2 cells. EO also inhibited the clonogenic growth of HepG2 cells. Myrtle EO doses ranging from 80 to 85 nl ml−1 did not elicit cytotoxic effects on the normal colon cells CCD 841 CoN cells but exhibited anti-quorum sensing activity against food-associated Pseudomonas fluorescens KM48 (KM48) and Pseudomonas orientalis KM149 (149). At sub-MIC levels, the EO significantly limited the production of autoinducers (i.e., AHL and PQS) and suppressed pseudomonad exopolysaccharide synthesis by 48% for KM48 and 41% for KM149. Myrtle EO at sub-MIC levels influenced the mRNA expression of exopolysaccharide genes algU (−2.5 and −1.5) and mucA (1.5 and 5.5) in KM48 and KM149, respectively. The application of the EO to the chitosan-based nanomatrix enhanced the antibacterial activity of the film against KM48 and KM149. These findings revealed the promising role of myrtle EO as a new generation antimicrobial in the food industry.

Smoked cooked loin is one of the most popular meat products in Poland. In this study, key volatile compounds in this traditional Polish meat product were determined using gas chromatography-olfactometry and aroma extract dilution analysis (AEDA). In total, 27 odor-active volatile compounds were identified, with flavor dilution (FD) factors ranging from 4 to 1024, with the highest FD factors noted for 2-methoxyphenol, 2-methoxy-4-(prop-2-enyl)phenol, and 2-methoxy-4-( E)-(prop-1-en-1-yl)phenol. Results of the quantitative analyses based on determinations with stable isotope dilution assays (SIDAs) and standard addition (SA), followed by calculations of the odor activity value (OAV), enabled identifying 24 of the volatile compounds responsible for flavor development in the analyzed smoked cooked loin. The highest OAVs were obtained for 2-methoxyphenol, 2-methyl-3-furanthiol, 1-octen-3-one, and 2-methyl-3-(methyldithio)furan.

The objective of the study was to determine the effect of grain preparation technology, extrusion cooking conditions, and triticale cultivars on physico-chemical properties of crisp bread. Triticale cultivars used in the experiments differed in protein content, starch content, amylolytic activity, and viscosimetric properties. The type of the twinscrew extruder used has an effect on starch degradation, phenolic contents, and antioxidant activity of the product, but a greater effect on those characteristics is found for grain scouring prior to extrusion. All factors had an effect on volatile compound amounts in crisp bread, but the direction and range of these changes were random in character. Results of this study show that triticale grain can be useful raw material for the production of flat bread.

The effect of selected plant additives (couch grass, artichoke, kale, nettle, ground buckwheat husks, broad beans, fenugreek seeds, and extracts of yellow tea and mulberry leaf) on the volatile compounds, color, texture, sensory attributes, polyphenols, and antioxidant properties of triticale crisp bread was studied. The volatile profile of control bread was dominated by lipid oxidation products with hexanal and (E)-2-nonenal predominant. The additives strongly modified the volatile profile of the extruded crisp bread. The greatest differences were recorded in the case of products with artichoke and kale additions, which had respectively about 12 and 8 times higher levels of total volatile compounds than the control crisp bread. The samples containing kale, buckwheat, and fenugreek as well as yellow tea extract characterized high levels of sulfur compounds, with methanethiol predominant. The additives, especially kale, nettle, and artichoke affected the color of the crisp breads, in most cases making them darker. In terms of texture only the crisp bread with addition of buckwheat husk was significantly harder than the control sample. On the basis of sensory evaluation it was stated that among all the additives, the artichoke and fenugreek resulted in dramatic deterioration in the extruded product taste. The used additives also affected the antioxidant properties of triticale crisp bread. The greatest content of total phenolic compounds and the highest antioxidant activity were observed for the bread with yellow tea extract addition (3.5- and 6.5-fold higher, respectively, than in control sample).

Meaty flavor is composed of a few hundreds of volatile compounds, only minor part of which are responsible for the characteristic odor. It is developed as a result of multi-directional reactions proceeding between non-volatile precursors contained in raw meat under the influence of temperature. The volatile compounds are generated upon: Maillard reactions, lipid oxidation, interactions between Maillard reaction products and lipid oxidation products as well as upon thiamine degradation. The developed flavor is determined by many factors associated with: raw material (breed, sex, diet and age of animal, conditions and process of slaughter, duration and conditions of meat storage, type of muscle), additives applied and the course of the technological process. The objective of this review article is to draw attention to the issue of volatile compounds characteristic for meat products and factors that affect their synthesis. Keywords: volatile compounds; meat flavor; precursors; meat products.

The identification of key odorants and production of 2-phenylethanol and related rose-like aroma compounds by a Galactomyces geotrichum MK01 species was examined in a fried cottage cheese. Odours were characterised as having cheesy, milky, buttery and rancid notes that were developed from 15 odorants: 2,3-butanedione, 3-(methylthio)-propanal, 3-isobutyl-2-methoxypyrazine, dimethylsulphide, dimethyltrisulphide, dimethyldisulphide, 3(sec-butyl)-2-methoxypyrazine, 1-octen-3-ol, β-damascenone, phenylacetaldehyde, 2-ethyl-3,5-dimethylpyrazine, 2-phenylethanol and phenylacetic acid, benzenemethanethiol and 5-methyl-2,3-diethylpyrazine as determined by sensory analysis and gas chromatography olfactometry. Analysis carried out after four days of cheese ripening, but before frying, indicated a distinct rose-like, honey flavour and high amounts of 2-phenylethanol, phenylacetaldehyde and phenylacetic acid. Statistical analysis demonstrated a significant correlation (P ≤ 0.05) between high amounts of rose-like compounds and the presence of the G. geotrichum MK017 species. Model experiments showed that the G. geotrichum MK017 species isolated from the fried cottage cheese was capable of biosynthesising 2-phenylethanol and related rose-like aroma compounds from l-phenylalanine.

The aim of this study was to characterize functional fermented caprine milk. Functional properties of fermented milks was an effect of increasing the level of whey proteins, MUFA and PUFA content in final product Milk used for experiments was obtained from experimental station belonging to Poznań University of Life Sciences. Feeding strategy was included modification by adding 12% of Camelina sativa cake. The fermentation process was done by using Lactobacillus acidophilus, Lactobacillus spp., and kefir grain microflora. The quality properties which were considered was metabolic activity, monosaccharide, disaccharide, lactic acid and ethanol content, aroma and fat profile. It was noted that increasing the content of functional components in processed milk caused changes in lactose, MUFA, PUFA and volatile acids content in final product.

Tempeh is a fermented food, popular mainly in south-east Asia, but also among vegetarians worldwide. It is produced by fermenting soybean or other beans with Rhizopus strains and usually eaten deep-fried, steamed or roasted. The flavour of tempeh depends upon the fermentation time, beans used and the (eventual) frying process. Our goal was to identify compounds responsible for the unique aroma of fermented and fried soy tempeh. Gas chromatography–olfactometry (GC–O) with the aroma extract dilution analysis (AEDA) approach, was used to determine key odorants after 1 and 5 days of fermentation and subsequent frying. Comprehensive gas chromatography–mass spectrometry (GC × GC–ToF-MS) was used for their quantitation using stable isotope dilution analysis (SIDA) or standard addition (SA) methods. Odour activity values (OAV) were calculated for 19 out of 21 key odorants. Tempeh was fermented for 5 days and fried, and the main aroma compounds were found to be the following: 2-acetyl-1-pyrroline, (FD = 1024, OAV 1380), 2-ethyl-3,5-dimethylpyrazine (FD = 512, OAV 338), dimethyl trisulfide, (FD = 512, OAV 900), methional (FD = 512, OAV 930), 2-methylpropanal (FD = 512, OAV 311) and (E,E)-2,4-decadienal (FD = 512, OAV 455). The frying process induced the increase or appearance of the main key odorants in tempeh.

The chapter focuses on the use of solid-phase microextraction (SPME) in the field of flavor analysis. Due to its robustness, versatility, and sensitivity, SPME is the dominating technique used for the extraction of flavor and volatile compounds in food nowadays. New developments in SPME technologies, including mainly fiber coatings and also cold fiber SPME, sampling in vacuum conditions, are discussed in this chapter. Specificity of food matrix in terms of extraction techniques, and specificity of food volatiles as well as the influence of sample preparation on extraction efficiency are described. The special emphasis is put on the quantitative aspects of SPME in the analysis of food flavors and off-flavors. Different extraction and calibration approaches are demonstrated. SPME is also compared to other extraction methods used in flavor and off-flavor analyses such as simultaneous distillation extraction (SDE), solvent-assisted flavor evaporation (SAFE), liquid–liquid extraction, purge and trap, and hydrodistillation. The usefulness of SPME in profiling of volatile compounds profiles is also outlined.

Jutrzenka is a sweet liquer wine produced in Poland from the grape variety of the same name, developed in Poland to withstand the harsh climate of winery regions. Jutrzenka wine has a characteristic aroma with strong fruity and flowery notes, which make it unique among other liquer wines as demonstrated in sensory profile analysis. The work was aimed at characterization of volatile compounds in this wine, with the emphasis on characterization of compounds responsible for its unique aroma. Gas chromatography-olfactometry (GC-O) was applied to identify the key odorants using aroma extract dilution analysis (AEDA) approach. To facilitate free and bound terpenes and C(13)-norisoprenoids identification solid phase extraction (SPE) was used followed by GC/MS. Among identified key odorants β-damascenone was the compound having the highest FD (4096), followed by isoamyl alcohol, 4-mercapto-4-methyl-2-pentanone (FD=2048), methional, linalool, ethyl decanoate (FD=1024) and ethyl hexanoate, furaneol (FD=512). Other significant compounds were ethyl 2-methyl propanoate, ethyl 2-methylbutanoate and phenyl ethyl alcohol. Determination of odor activity values (OAV) showed the highest values for β-damascenone (566), 4-mercapto-4-methyl-2-pentanone (288) ethyl hexanoate (32) and linalool (7). Jutrzenka exhibited also a rich profile of free, and to lesser extent bound terpenes.

Jakość ziarna pszenicy zależy od wielu cech, spośród których twardość ziarna uważana jest za jedną z ważniejszych. Rezultaty wielu badań wskazują, że twardość ziarna ma związek z wymiałowością oraz z podstawowymi wskaźnikami wartości wypiekowej, jak wodochłonność mąki, test sedymentacyjny i objętość chleba. Praca przedstawia wyniki badań cech technologicznych oraz twardości ziarna 104 rodów pszenicy ozimej polskiej hodowli. Rody te oraz odmiany wzorcowe Muszelka i Bogatka badane były w doświadczeniach polowych w dwóch miejscowościach. Określano — używając aparatu NIR System Infratec 1241 Analyzer (Foss, Hillerod, Denmark) — na 600-gramowych próbach pełnego ziarna relatywną twardość ziarna, zawartość białka, gluten mokry, liczbę sedymentacji Zeleny’ego oraz parametr alweograficzny. Uzyskane dane analizowano statystycznie stosując wielozmienną analizę wariancji i pokrewne metody wielu zmiennych. Utworzono teoretyczną linię charakteryzującą się najkorzystniejszymi wartościami analizowanych cech, z którą porównywano badane rody, zarówno pod względem poszczególnych cech, jak i wszystkich cech traktowanych łącznie. Zastosowane metody pozwoliły wyodrębnić grupę rodów nie różniących się istotnie od najlepszej linii pod względem wszystkich analizowanych parametrów jakościowych. Zaproponowane podejście może być wykorzystane w programach hodowli pszenic jakościowych.

The unique flavor of Oscypek, a Polish ewe's milk smoked cheese, is described as slightly sour, piquant, salted, and smoked. In this paper with the application of gas chromatography-olfactometry (GC-O) and combination of aroma extract dilution analysis (AEDA) 20 potent odorants of this cheese have been identified within the flavor dilution factor (FD) range of 4-2048. Among them, 2-methoxyphenol, 2-methoxy-4-methylphenol, 4-methylphenol, and butanoic acid showed the highest FD factors. Quantification results based on labeled standard addition followed by calculation of odor activity values (OAV) of 13 compounds with the highest FD factors revealed that 11 compounds were present at concentrations above their odor threshold values and therefore mostly contribute to the overall aroma of smoked ewe's milk cheese. Six of those compounds were represented by phenolic derivatives, with the highest OAV for 2-methoxyphenol (1280). Analysis of key odorants of an unsmoked cheese sample showed that the smoking process had a fundamental influence on Oscypek aroma formation.

BACKGROUND:OscypekisaspecialtypeofPolishsmokedewecheesewithauniqueflavourdescribedasslightlysour,piquant, saltedandsmoked.Inthisstudythevolatile,sensoryandmicrobialprofilesofOscypekcheesewereanalysedduringitsvarious preparation stages of curding, scalding, brining and smoking. RESULTS:Thesmokedewecheesewascharacterisedby54volatilecompoundsbelongingtoninedifferentchemicalgroups(free fatty acids, esters, ketones, alcohols, aldehydes, furans/furanones, phenols, sulfur compounds, terpenes). The sensory aroma profile analysis of unsmoked and smoked cheese showed an important correlation with the analysis of volatile compounds. The microbial profile data indicated that in smoked cheese such as Oscypek the levels of selected bacteria diminishedafter the curding stage as a result of the subsequent scalding, brining and smoking stages. CONCLUSION: From the results it can be concluded that, although the analysed smoked cheese consisted of three groups of compounds, the first derived from biochemical reactions (free fatty acids, esters, ketones, alcohols, aldehydes, sulfur compounds), the second from smoking (furans and furanones, phenols) and the third from milk flavour (terpenes), it is the smoking process that mainly influences its typical flavour. c � 2011 Society of Chemical Industry

The study was aimed at sensory analysis and volatile content determination in fried cheese. Fried cheese was produced under commercial conditions from acid tvarog ripened and fried with no butter added (non-fat) and with an addition of butter at 4:1 (reference cheese). Cheese was evaluated immediately after production and after 6 weeks of storage at 4 o C. Total and casein nitrogen, water and fat were assayed in cheese. Sensory analyses of cheese descriptors were conducted by profi ling on a 0–10 scale, while volatiles were isolated by solid phase microextraction (SPME) technique. The dominant aroma in reference cheese was cowy/phenolic and cooked, while in non-fat cheese it was cooked and free fatty acid. Sulphur aroma was least perceptible in reference and non-fat cheese. After 6-week storage the only signifi cant changes were weakened cooked aroma in non-fat cheese and waxy/crayon aroma in reference cheese. Differences in profi le analysis of full and non-fat cheese were refl ected in amounts of determined volatiles, especially total sulphur compounds, acids, methyl ketones, terpenes and esters.