Search

In this study, the physicochemical, textural, rheological, bioactive, and sensory properties, and probiotic viability of synbiotic ice creams (containing inulin and Lactobacillus brevis PML1) were evaluated during frozen storage. The inulin-rich samples had higher carbohydrate and total solid contents and lower moisture content compared to other synbiotic samples; however, the pH value and acidity of the ice creams were not remarkably changed upon inulin addition. Although the addition of inulin led to a marked increase in the overrun, viscosity, and hardness of the formulations, the melting rate and fat destabilization were decreased in the inulin-enriched samples. The luminosity and chroma of the ice creams containing inulin were also more intense in comparison with other synbiotic ice creams. The antioxidant activity of the ice creams was improved when inulin was added as a prebiotic sugar in the formulations. Moreover, the synbiotic ice creams had higher thermodynamic stability, probiotic viability, and sensory properties than the inulin-free counterparts. The synbiotic ice creams (inulin + L. brevis PML1) could be therefore introduced as a novel functional product in the food industry.

There is an increasing demand for bioactive-loaded bio-based packaging materials to obtain food products with extended shelf-life and improved quality. The aims of the present study were to fabricate a Citrus paradise essential oil (CPEO)-loaded Lallemantia iberica seed mucilage (LISM) based edible coating and to evaluate the effects of the CPEO-LISM edible coating on the preservation of lamb slices during cold storage for 9 days. CPEO was rich in limonene (79.4%) with superb antioxidant and antimicrobial properties. Its incorporation into the edible coating (at 0, 0.5, 1, 1.5, and 2% v/v) effectively inhibited the microbial growth (total viable count, psychrotrophic count, Escherichia coli, Staphylococcus aureus, and fungi) and lipid oxidation (peroxide and thiobarbituric values) in lamb slices. The meat color (L*, a*, b*) and sensory properties were also preserved by the edible coating containing CPEO, and the bioactive edible coating based on LISM and CPEO, particularly LISM + 2%CPEO significantly inhibited quality deterioration of lamb slices and improved the shelf-life of the meat (> 9 days). The results suggested that the LISM-CPEO edible coating could be developed as an antioxidant and antimicrobial packaging to improve the shelf-life of various meat products.

Gamma‐aminobutyric acid (GABA) is a pharmaceutical, bioactive amino acid that can produce by some species of Lactic Acid Bacteria (LAB). For the first time, we evaluated the production of GABA by Lactobacillus brevis PML1 in the medium that contain the contaminant food bio‐product like dairy sludge and soybean meal. GABA production was analyzed by chromatography (TLC, HPLC) and the features of fermented extract which contains this amino acid were evaluated. The results of Response Surface Methodology (RSM) of Central Composite Design (CCD) at p, The results of response surface methodology (RSM) of central composite design (CCD) at p

There has been an increasing interest in the investigation of novel eco-friendly packaging materials. An edible film based on Malva sylvestris flower gum was fabricated with 40%, 50%, and 60% glycerol and sorbitol using casting method. FTIR analysis was applied to identify the functional groups of films with different concentrations of plasticizers. The lightness of the samples did not affect upon increasing the sorbitol and glycerol; nevertheless, the samples tended to be green and yellow. SEM images indicated that glycerol-based films enjoy heterogeneous and porous surfaces compared to the sorbitol-based samples. Although Tensile Strength and Young's Modulus characteristics declined considerably (p

Background Traditional fermented products are a rich source of microorganisms which may have remarkable probiotic properties even more significant than probiotic strains of human origin. In this study three Lactobacillus plantarum and one Lactobacillus fermentum strains, isolated from either Iranian traditionally fermented products or children's feces, identified with molecular methods and selected based on high acid resistance, were investigated for their probiotic properties in vitro and compared with standard probiotic strains of the species; L. plantarum ATCC 14917, L. fermentum PTCC 1744 and L. acidophilus ATCC 4356. Results Most of the isolates showed a high survival rate under gastrointestinal tract conditions and L. plantarum strains displayed a moderate ability to adhere to human colon adenocarcinoma cell line, HT-29. Neutralized cell free culture supernatants of L. plantarum strains were capable of inhibiting pathogens. Almost all of the strains were resistant to vancomycin and streptomycin and susceptible to other clinically relevant antibiotics. Isolated strains exhibited low to moderate autoaggregation (Auto-A), co-aggregation (Co-A) and hydrophobicity, following a strain specific manner. None of the strains invaded into HT-29 cells while strain PF11 could significantly decrease the number of adhering pathogenic bacteria. Most of the strains increased apoptosis of HT-29 cells, though they had no effect on human umbilical vein endothelial cells (HUVECs). Conclusion Favorable probiotic properties of strains PL4 and PF11 along with their anticancer activity imply their potential for clinical or technological applications. However, further in vitro/in vivo investigations are recommended. © 2019 Society of Chemical Industry.

Gamma-aminobutyric acid (GABA) is an active bio-compound with versatile physiological functions and, therefore, considerable attention is given to developing GABA-enriched functional foods. In this study, central composite design was used to optimize the fermentation conditions to obtain the highest GABA yield by Lactobacillus brevis. The optimal conditions of GABA production (1473.44 ppm) included 5% soy protein isolate, 3% inulin, and 96 h fermenting time at 37 °C. GABA-rich fermented solution (GABA-EFS) under optimal conditions had an appropriate emulsifying activity and water/oil holding capacity. Also, the reducing power assay revealed that GABA-EFS has electron donor groups with the ability to terminate the free radical chain reactions. Minimum inhibitory concentration results showed that Candida albicans was the most sensitive microorganism; whilst, Staphylococcus aureus and Listeria innocua were the most resistant bacteria towards GABA-EFS. In addition, GABA production was confirmed by pre-staining thin layer chromatography and fourier transform infrared spectroscopy. The results suggested that the GABA-EFS could be applied in the food industry as a functional product.

Chitosan (1%) was glycated with inulin (0.5, 1, and 2%) via the Maillard reaction at various initial pH values (5, 5.5, and 6). Higher pHs led to a greater pH drop and increase in the intermediate products and browning intensity (BI). The chitosan–inulin conjugates were then classified into three levels of low, medium, and high BI through K-means clustering in order to investigate the effect of BI development on the antioxidant and antimicrobial attributes of the conjugates. Covalent linkage between chitosan and inulin was confirmed by fourier transform infrared spectroscopy. High BI chitosan–inulin conjugate had significantly higher antioxidant property compared to chitosan and other conjugate fractions. In addition, the conjugates obtained at low pH values mainly presented greater antimicrobial activities than those prepared at high pHs. It can be concluded that chitosan–inulin Maillard-born conjugates can be used as novel antioxidant and antimicrobial prebiotic-based ingredients for food applications.

A high-pressure carbon dioxide technique was optimized by employing of response surface methodology. A quadratic model was used to predict process behavior. According to results, the extraction time (20–60 min) and pressure (100–200 bars) had statistically significant effects on anthocyanin, total phenolic, ascorbic acid contents and antioxidant activity of barberry fruit extracts. The maximum yields of anthocyanins, phenolic compounds, and vitamin C were 178.658 mg/L, 329.815 mg GAE/100 mL, and 3468.7 mg/L, respectively. Antioxidant activity of about 84% was also achieved. The optimum extraction pressure and time were defined as 200 bars and 44.64 min, respectively. Experimental values for various responses at the optimum conditions matched with the predicted values. High-performance liquid chromatography revealed the presence of six different types of anthocyanins, namely cyaniding-3,5-diglucoside, delphinidin-3,5-diglucoside, delphinidin-3-glucoside, pelargonidin-3,5-diglucoside, cyanidin-3-glucoside, and pelargonidin-3-glucoside in the samples. Response surface methodology was employed successfully to optimize the extraction conditions of barberry fruit bioactive compounds.

In vitro antifungal activity against Aspergillus niger was used to screen the lactic acid bacteria (LAB) isolated from whole wheat sourdough. Sequencing results of the PCR products led to the identification of Lactobacillus reuteri as the selected isolate. The LAB isolate had a proper anti-aflatoxigenic capability, and it reduced the amount of B1, B2, G1 and G2 aflatoxins, based on the results of HPLC analysis. n-Decanoic acid, 3-hydroxydecanoic acid and 3-hydroxydodecanoic acid were also identified as the bioactive ingredients using gas chromatography/mass spectrometry in the antifungal fraction obtained from preparative thin-layer chromatography of the L. reuteri culture filtrate. Furthermore, it was revealed that the sourdough fermented with the selected LAB isolate had a significant influence (P

Paraprobiotics are inactivated probiotics that exert various health and technological benefits making them suitable for production of functional yogurt. In the present study, probiotic yogurt containing Lactobacillus acidophilus ATCC SD 5221 and Bifidobacterium lactis BB-12 and paraprobiotic yogurt containing inactivated form of the mentioned bacteria were produced and were compared regarding microbiological, biochemical, and physical properties during 28 days of storage at refrigerated temperature. Results revealed that the greatest mean pH drop rate, mean acidity increase rate, mean redox potential increase rate, final acidity and final redox potential were observed in yogurt containing inactivated L. acidophilus added before fermentation. The highest lactic acid after 28 days of storage was obtained in samples prepared by addition of paraprobiotic form of L. acidophilus after fermentation. Yogurt samples with B. lactis and L. acidophilus added after fermentation showed the highest and lowest acetic acid level, respectively after 28 days of storage. The samples containing L. acidophilus and B. lactis had the highest acetaldehyde on day 0 while on day 28, L. acidophilus had more impact on acetaldehyde generation in yogurts. Addition of paraprobiotics increased viability of starter cultures. In addition, incorporation of inactivated probiotic cells into yogurt resulted in lower syneresis and the higher WHC compared to probiotic yogurt samples. Regarding color parameters, it was observed that color parameters (a*, b* and L*) were not influenced by paraprobiotic in probiotic and paraprobiotic yogurts. Overall, it can be concluded that incorporation of paraprobiotics into yogurt involves less technological challenges and can be considered as a suitable appropriate alternative for probiotics in development of functional yogurt.

Wheat germ is produced as a by‐product during wheat milling operations and is a relatively inexpensive protein source that, in spite of its exclusive nutritional properties, is mostly used for animal feed formulation and has limited use in the food industry. In this study, wheat germ extract (WGE) was microencapsulated by spray and freeze drying and with different ratios of maltodextrin to whey protein concentrate (M‐W) as the coating material and then physicochemical properties of the microcapsules were evaluated. Results showed decreased moisture content and increased solubility, lipase activity, acid phosphatase activity, and both lipase and acid phosphatase microencapsulation efficiency with increasing M‐W ratios in both drying methods. The M‐W ratios had no significant effects on the DPPH free radical scavenging activity in both methods. With increasing M‐W ratios, particle size decreased and bulk density increased in the spray drying method, while particle size increased and bulk density decreased in the freeze drying method. Spray drying elevated solubility, DPPH free radical scavenging activity, lipase activity, acid phosphatase activity, and both lipase and acid phosphatase microencapsulation efficiency, in comparison with the freeze drying method., In this study, wheat germ extract was microencapsulated by spray and freeze drying and with different ratios of maltodextrin to whey protein concentrate as the coating material, and then, physicochemical properties and enzymatic activity of the microcapsules were evaluated.

Purpose The aim of the present study was to evaluate the antifungal activity, anti-aflatoxigenic capability, and technological functionality of the selected lactic acid bacteria (LAB) isolated from wheat sourdough. Methods The preselected LAB isolates were screened based on their antifungal activities and acidification capacities. Then, the antifungal compounds were identified using gas chromatography/mass spectrometry in the selected LAB culture filtrate obtained from its preparative thin-layer chromatography. The HPLC-based analysis was also used to investigate the anti-aflatoxigenic potentials of the selected LAB isolate. Finally, controlled sourdough (containing selected LAB isolate as starter culture) was used to produce loaf bread, and properties of the product were evaluated in terms of hardness, phytic acid content, overall acceptability, and surface moldiness. Results Molecular approaches led to the identification of Pediococcus pentosaceus as the selected LAB isolate. In vitro and in situ antifungal activities of the selected LAB against Aspergillus niger were verified. Antifungal metabolites of the LAB included fatty acid ester, hydroxylated fatty acid ester, an antimicrobial compound, and cyclic dipeptide. Potent anti-aflatoxigenic capabilities of the LAB isolate and cyclic dipeptide (which was identified in the antifungal fraction of the LAB) were also verified. To our best knowledge, the cyclic dipeptide detected in the present study has never been shown before to possess anti-aflatoxigenic effect. Furthermore, the results revealed that controlled sourdough improved the techno-functional properties of the produced loaf wheat bread. Conclusion Altogether, our findings indicate that the selected P. pentosaceus isolate exhibiting proper characteristics can be used as a bio-preservative and bio-improver in the processing of clean-label breads.

Mannoprotein (mannan), an important cell wall component of Saccharomyces cerevisiae, is a bioactive glycoprotein that has aflatoxin binding effect. In this study, mannan from the cell wall of Saccharomyces cerevisiae was extracted and lyophilized. Aflatoxin binding assay of mannan in water/methanol were spiked with 0.5 μl. Aflatoxin standard solution showed that aflatoxin binding and mannan concentration had a positive correlation (p

The aerial parts of Equisetum telmateia have been used as a source of biologically active compounds to treat inflammatory, diarrhea, stomach-ache, eczema and mouth infections in traditional medicine. The aim of this work is to evaluate the extraction yield, chemical compositions, antioxidant activity and antimicrobial activity of E. telmateia extracts on Staphylococcus aureus, Bacillus cereus, Escherichia coli, Salmonella typhi and Candida albicans. Chemical compositions E. telmateia was analyzed by high performance liquid chromatography (HPLC) using a C18 column. Analysis of E. telmateia extract by HPLC allowed the identification of Kaempferol 3-O-(6″-O-acetylglucoside) as major compound. The antioxidant activity of extracts was examined by measuring their ability to sequestrate 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. The results showed that the DPPH (IC50 = 70.83 ± 0.2 μg/ml) were obtained in the case of supercritical fluid extraction (SFE) extract. MIC microdilution assay were used to determine the antimicrobial activities. Contrary to lower extraction yield (9.6 ± 0.5), the SFE extract exhibited the highest antimicrobial potency with MIC and MBC values of 32 mg/ml against S. aureus compared to the other extracts. The results suggest that SFE method is more appropriate for extraction of E. telmateia biologically active substances with antimicrobial and antioxidant activity than conventional solvent extraction methods.

In most bacteria, Glutamate decarboxylase (GAD) activity significantly reduces at pH > 6. Since l -glutamate is neutral to slightly alkaline, a large amount of hydrochloric acid must be added to the reaction mixture. Acidic reaction conditions greatly increase the corrosion of production equipment and shorten the life of manufacturing equipment. Therefore, this study aims at studying the overexpression of recombinant GAD that is active at the neutral pH and high-level production of γ-aminobutyric acid. A gene sequence encoding GAD of Enterococcus faecium DO was cloned into PET21a (+) and was overexpressed in Escherichia coli BL21 (DE3). The construct was confirmed by colony PCR and double digested with BamHI and XhoI. The result from Western blot analysis showed a signal band at the molecular mass of 54 kDa. The specific activity of the recombinant GAD was 78.17 U mg−1 at 45 °C and pH = 6.6. It was reduced rapidly when pH > 7.8. The Km, Vmax, and kcat values of recombinant GAD were 1.8 mM, 12.9 μmol L−1 min−1, and 0.43 s−1, respectively. Therefore, recombinant GAD is a potent candidate for GABA production in food and pharmaceutical industries, because it increases the efficiency of GABA synthesis, especially in foods with a neutral pH range.

Paraprobiotic yogurts were produced using killed cells of Lactobacillus acidophilus ATCCSD 5221 and Bifidobacterium lactis BB-12. Fourier-Transform Infrared Spectroscopy (FTIR-ATR), as an important and sensitive method for detecting chemical bonds in dairy product, was used to specify the FTIR-ATR spectra and detect suitable spectral regions for probiotics as well as paraprobiotics (0-day). Principal Component Analysis (PCA) was employed to specify the spectra. In PCA, two principal components (PC1 with 37.07%, PC2 with 23/40%) were found with cumulative variance greater than 90%. The microstructure was tested using field emission scanning electron microscopy. Samples containing paraprobiotics, added before fermentation, showed a different structure compared to probiotic samples with more open and larger size of pores. Treatments containing probiotics and paraprobiotics added after fermentation revealed an open and loose structure as well as a more compact structure. In yogurt samples without probiotics and paraprobiotics, an open and spongy structure was observed. The sample containing killed cells of L. acidophilus ATCCSD 5221 and B. lactis BB-12 added before fermentation exhibited the lowest syneresis, highest water holding capacity, and highest apparent viscosity due to the presence of exopolysaccharides and cell components.

The aim of this study was to evaluate the probiotic potential of lactic acid bacteria (LAB) strains isolated from Horreh. Some probiotic properties, e.g., resistance to acid, bile tolerance, antibacterial activity, and antibiotic susceptibility, were investigated. A total of 140 Gram-positive and catalase-negative isolates from Horreh were subjected to identification and grouping by cultural methods and the 16S rRNA sequencing. The new isolates were identified to be Lactobacillus (fermentum, plantarum, and brevis) Weissella cibaria, Enterococcus (faecium and faecalis), Leuconostoc (citreum and mesenteroides subsp. mesenteroides) and Pediococcus pentosaceus. Probiotic potential study of LAB isolates showed that Lb. plantarum and Leu. mesenteroides subsp. mesenteroides isolates were able to grow at pH 2.5 and 3.5. Lactobacillus plantarum (isolate A44) showed the highest cell hydrophobicity (84.5%). According to antibacterial activity tests, Listeria innocua and Staphylococcus aureus were the most sensitive indicators against the selected LAB strains, while Escherichia coli and Bacillus cereus were the most resistant. In addition, all the isolated LAB species were resistant to vancomycin. The results of the present study suggested that the Lactobacillus fermentum and plantarum isolated from Horreh, characterized in this study, have potential use for industrial purposes as probiotics.

The aim of this study was to determine the chemical composition, antioxidant potential and phytochemical analysis of Artemisia dracunculusas as well as its antibacterial and antifungal effects (individually or in combination with Coriandrum sativum and Plantago major) “in vitro”. Total phenolic content, total flavonoid content and anthocyanin content were determined through spectrophotometric methods. Antioxidant potential was determined calorimetrically for 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity. The disk diffusion method and hole-plate diffusion method were used to assess the diameter of the inhibition zone. The pour plate method was adopted to determine the susceptibility of the pathogenic strains against Artemisia dracunculusas extract. The broth microdilution and agar dilution methods were employed to measure the minimum inhibitory concentration. The minimum bactericidal/fungicidal concentration was measured using the wells in which no turbidity/color change was observed. The fractional inhibitory concentration index (FICI) was also determined for the extracts. The chemical composition of Artemisia dracunculusas essential oil was analyzed by gas chromatography and gas chromatography/mass spectrometry. The results showed that IC50 of A. dracunculus was 65.4 μg/ml, Total phenolic content was equal to 24.10 mg GAE/g, total flavonoid content was 20 mg QE/g. The major components included p-Allylanisole (84.00%), Ocimene (E)-beta (7.46%), Ocimene (Z)-beta (6.24%) and Limonene (1.42%), respectively. The extract of A. dracunculus exhibited strong antimicrobial activity against fungi with an average inhibition zone of 14.70 mm. All bacteria (except Streptococcus pyogenes and Staphylococcu aureus) were more resistant than Candida albicans. Regarding the checkerboard data, 10 FICIs (≤0.5) showed the synergistic effect, whereas eight FICIs (>0.5 to 1) indicated the additive effect.

In this study, Plantago major seed mucilage (PMSM) was extracted from whole seeds using hot-water extraction (HWE). The dill (D) essential oil components were identified through gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) and its antioxidant properties were examined through the methods of 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant potential (FRAP) and s-carotene-linoleic acid assay (B-CL). Total phenolic content (TPC) was characterized through the Folin-Ciocalteu method and the antimicrobial effect was evaluated on 10 pathogenic microorganisms. PMSM edible coating incorporated were prepared in four different concentrations of essential oils, including 0, 0.5, 1 and 1.5% (w/w). The control and the coated beef samples were analyzed periodically for microbiological (total viable count, psychrotrophic count, Escherichia coli, Staphylococcus aureus and fungi), chemical (thiobarbituric acid, peroxide value and pH), and sensory characteristics. The IC50, FRAP, B-CL and TPC of the dill essential oil were equal to 11.44μg/ml, 9.45mmol/g, 82.86 and 162.65μg/ml GAE, respectively. PMSM extended the microbial shelf life of beef by 3days, whereas the PMSM+0.5%D, PMSM+1%D and PMSM+1.5%D resulted in a significant shelf life extension of the beef by 6, 9 and 9days, respectively, as compared to the control samples.

Cold plasma is a novel technology for surface decontamination. Almond slices can be contaminated with different microorganisms during their production. In the current research, the atmospheric argon plasma treatment (5, 10, 15, and 20 min) was used to decontamination of almond slices surface. Microbial load, Color, peroxide value, hardness, and sensory properties of slices was comprised with untreated samples (control). Descriptive sensory evaluation about color, flavor, crispiness, crunchiness, and hardness of almond slices were performed. According to the results of the microbial tests, Total count, molds and yeasts, and Staphylococcus aureus of almond surface decreased about 2.95 log cfu/g, 1.81 log cfu/g, and 2.72 log cfu/g after 20 min of plasma treatment, respectively, provided that microbial reduction increased more by increasing the treatment time. Coupled with the color evaluation, peroxide value and sensory attributes didn't change during plasma treatment. Having said that, the hardness of slices was changed by increasing treatment time. Furthermore, Principal Component Analysis and cluster analysis were performed for sensory evaluation. In light of the consumer's point of view, firstly 10 min and secondly 15 min plasma treatment can be more desirable.

The oxidative stability and lipid modifications of Doogh prepared with Lactobacillus plantarum LS5 and control Doogh were compared during storage for 22 days. In vitro scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals showed that L. plantarum LS5 had radical scavenging activities (49.6%). Peroxide value, conjugated diene value and anisidine value measurements in Doogh lipid samples in combination with Fourier transform infrared spectroscopy demonstrated that Doogh prepared with L. plantarum LS5 was more stable than the control against formation of primary and secondary oxidation products. Furthermore, higher concentrations of short-chain fatty acids (butyric and caproic) and unsaturated fatty acids were found in Doogh treated with L. plantarum LS5. Changes in the thermograms of all samples were also observed. Results of differential scanning calorimetry indicated that melting points of lipids from treated Doogh were lower than for the control. It was concluded that L. plantarum LS5 could be used as a natural preservative in functional dairy products and could beneficially affect the consumer by providing dietary sources of antioxidants.

The main objective of our research was development of a modified poly glutamic acid (PG) films by polylysine (PL) at different PL content (0, 2, 4 and 6%) as a microbioreactor to growth and protect Gamma-aminobutyric acid (GABA) producing bacteria. The addition of PL groups between the PG backbones was completely corroborated using FTIR analysis. Scanning electron micrographs confirmed the high changes in the microstructure of PG films by PL. Density, thickness, moisture content, L* (lightness), b*(yellowness-blueness), WI (whiteness index), opacity, and elongation at break were increased with increasing the PL content. Whereas ΔE (Total color difference) and tensile strength were decreased, simultaneously. The change of water vapor permeability and a* (redness-greenness) value of PG-PL were independent from PL content. The PG-PL films were active packaging material against food borne pathogens (i.e. Bacillus cereus and Escherichia coli). But they had not any side effects on viability of probiotic bacterium (i.e. Lactobacillus brevis G42) after drying process. It is inferable that PG-PL is a suitable candidate for the development of edible coating and film with high antimicrobial properties against food borne pathogen without any side effect on probiotic viability.

This study describes the potential use of colorimetric parameters (L*, a*, b*, C* and h*) obtained from image processing technique (IPT) to predict the contents of spoilage indicators (histamine, total volatile nitrogen and trimethylamine nitrogen) in rainbow trout fillets (600±50 g) stored at 4±1 °C during time intervals of 0, 5, 10, 15 and 20 days. Compared to 10 days, storage for 15 or 20 days provoked major changes in the colour of fish fillets, especially the C* and h* parameters (P 0.05) from 0.03 to -0.13 during the first ten days, followed by a significant (P

Winter salad is a kind of pickle made of different vegetables and is consumed specially in Khorasan Province. The spontaneous fermentation process is mainly carried out by lactic acid bacteria (LAB). The aim of this study was to isolate and identify the LAB species involved in winter salad fermentation at different fermentation time intervals to introduce the native strains. In order to classify selected isolates that seemed LAB, according to preliminary experiments, biochemical tests were performed. Forty-five selected isolate genotypically identified based on 16S rRNA gene sequencing. The results show that the analysis with 16s rRNA gene sequencing could successfully identify eight species, including Pediococcus (51.1%), Lactobacillus (26.7%), Weissella (11.1%), Enterococcus (6.7%) and Leuconostoc (4.4%). Although Weissella cibaria and Lactobacillus plantarum were the predominant LAB in the early periods of winter salad fermentation, Pediococcus pentosaceus was the predominant LAB at the later periods. Practical Applications Fermented vegetables are usually used as seasoning in Iran. To our knowledge, this is the first study to examine fermented vegetables lactic acid flora using molecular methods, in Iran. Indigenous starter bacteria are normally considered as genetic resources, and strains obtained from this study could be used in the industry and some of them may be considered as probiotic strains.

Response surface methodology (RSM) was used to optimize pizza cheese containing carrot extract. The effects of two important independent variables including soybean oil (5%–20%) and carrot extract (5%–20%) were studied on physicochemical and textural properties of pizza cheese containing carrot extract. According to the results, RSM was successfully used for optimizing formulation of pizza cheese containing carrot juice. Results of this study revealed that oil (A), carrot (B), AB, square term of carrot (B2), B, AB, square term of oil (A2), B2, AB, AB, A2B, A2, A2, A, A2, A2, AB, and AB 2 had the most effect on moisture, acidity, stretch, L*, a*, b*, hardness, meltability, springiness, peroxide value (PV), cohesiveness, chewiness, gumminess, fracture force, adhesiveness force, stiffness, flavor, and overall acceptability, respectively. A formulation upon 20% oil and 10.88% carrot extract was found as the optimal formulation for pizza cheese containing carrot extract. At the optimal formulation, PV, L*, a*, b*, meltability, stretch, cohesiveness, springiness, gumminess, chewiness, adhesive force, flavor, texture, and overall acceptability at the optimum formulation were measured 2.23, 82.51, −3.69, 18.05, 17.86, 85.61, 0.41, 7.874, 23.7, 0.27, 0.61, 3.50, 3.95, and 3.65, respectively.

Principle component analysis (PCA) was employed to examine the effect of the exerted treatments on the beef shelf life as well as discovering the correlations between the studied responses. Considering the variability of the dimensions of the responses, correlation coefficients were applied to form the matrix and extract the eigenvalue. Antimicrobial effect was evaluated on 10 pathogenic microorganisms through the methods of hole-plate diffusion method, disk diffusion method, pour plate method, minimum inhibitory concentration and minimum bactericidal/fungicidal concentration. Antioxidant potential and total phenolic content were examined through the method of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Folin-Ciocalteu method, respectively. The components were identified through gas chromatography and gas chromatography/mass spectrometry. Barhang seed mucilage (BSM) based edible coating containing 0, 0.5, 1 and 1.5% (w/w) Tarragon (T) essential oil mix were applied on beef slices to control the growth of pathogenic microorganisms. Microbiological (total viable count, psychrotrophic count, Escherichia coli, Staphylococcus aureus and fungi), chemical (thiobarbituric acid, peroxide value and pH) and sensory characteristics (odor, color and overall acceptability) analysis measurements were made during the storage periodically. PCA was employed to examine the effect of the exerted treatments on the beef shelf life as well as discovering the correlations between the studied responses. Considering the variability of the dimensions of the responses, correlation coefficients were applied to form the matrix and extract the eigenvalue. The PCA showed that the properties of the uncoated meat samples on the 9th, 12th, 15th and 18th days of storage are continuously changing independent of the exerted treatments on the other samples. This reveals the effect of the exerted treatments on the samples.

Quince seed mucilage (QSM) films containing oregano essential oil at 1, 1.5 and 2% v/v were prepared to examine their antibacterial, antioxidant, physical, thermal, microstructural and mechanical properties. Addition of 1% oregano essential oil did not affect the oxygen and water vapor permeability of the films. Incorporating OEO, increased total color differences (ΔE) and decreased whiteness index (WI). A decrease of elastic modulus (EM) and tensile strength (TS) accompanied with an increase in elongation at break (%EB) was observed with increasing oil concentration up to a level of 2.0% (w/w). Antimicrobial and antioxidant properties significantly increased with the incorporation of EO (p < 0.05). The antimicrobial activity of the QSM films incorporated with oregano essential oil was screened against 11 important food-related bacterial strains by agar disc-diffusion assay. Films containing 1% of OEO were not effective against Salmonella typhimurium and Pseudomonas aeruginosa but exhibited a strong inhibitory effect on the growth of Staphylococcus aureus, Escherichia coli, Shewanella putrefaciens and Yersinia enterocolitica as evidenced by minimal growth around the film cuts. Our results pointed out that the incorporation of oregano essential oil as a natural antibacterial agent has potential for using the developed film as an active packaging.

The effects of quince seed mucilage film (QSMF) containing oregano (O) or thyme (T) essential oil on shelf life extension of rainbow trout (Oncorhynchus mykiss) fillets during refrigerated storage (4°C) were evaluated over a period of 18days. Films were prepared in four different concentrations of essential oils, including 0, 1, 1.5 and 2%. The control and the wrapped fillet samples were analyzed periodically for microbiological (aerobic and psychrotrophic count, Pseudomonas spp., H2S-producing bacteria, lactic acid bacteria, and Enterobacteriaceae), chemical (TBA, TVB-N, TMA-N), and sensory characteristics. Bacteria grew most quickly in trout fillets stored in air, followed by those wrapped with QSMF and the lowest counts were in wrapped samples with QSMF+2%T. Pseudomonas spp., Enterobacteriaceae and LAB counts were significantly lower in samples wrapped with QSMF+2%T. The lowest TBA value was obtained in fillets wrapped QSMF containing 2% oregano essential oil. The strong antioxidant activity of QSMF+2%O was related to the composition of oregano essential oil. The GC analysis of essential oil components revealed that carvacrol (81.85%) was the major component of oregano essential oil. TBA value varied for all treatments and remained lower than 2mg MDA/kg throughout storage. The formation of TVB-N, TMA-N increased with time of storage. TVB-N and TMA-N correlated well with the microbiological data, indicating that along with TVB-N, TMA-N may serve as a useful index for fillets spoilage. QSMF extended the microbial shelf life of rainbow trout fillets by 2days, whereas the QSMF+1%O, QSMF+1.5%O, QSMF+2%O, QSMF+1%T, QSMF+1.5%T and QSMF+2%T resulted in a significant shelf life extension of the trout fillets by 3, 5, 9, 6, 10 and 11days, respectively, as compared to the control samples.

In this study thyme essential oil (TEO) concentrations ranging from 0% to 2.0%, incorporated in quince seed mucilage (QSM) film were used. Antibacterial activity, physical, mechanical, barrier and antioxidant properties of QSM films were evaluated. The antimicrobial activity of the QSM films incorporated with thyme essential oil was screened against 11 important food-related bacterial strains by agar disc-diffusion assay. Films containing 1% of thyme essential oil were effective against all test microorganisms and exhibited a strong inhibitory effect on the growth of Shewanella putrefaciens, Listeria monocytogenes and Staphylococcus aureus. QSM films exhibited some antioxidant activity, which was significantly improved by the addition of the essential oil. A reduction of the glass transition temperature, as determined by differential scanning calorimetry (DSC), was caused by addition of thyme essential oil into the QSM films. Scanning electron microscopy was carried out to explain structure–property relationships. Incorporating thyme essential oil into edible QSM films provides a novel way to improve the safety and shelf life of ready-to-eat foods.

This paper deals with the conjugation of durian seed gum (DSG) with whey protein isolate (WPI) through Maillard reactions. Subsequently, the functional properties of durian seed gum in the non-conjugated (control sample) and conjugated forms were compared with several commercial gums (i.e., Arabic gum, sodium alginate, kappa carrageenan, guar gum, and pectin). The current study revealed that the conjugation of durian seed gum with whey protein isolate significantly (p < 0.05) improved its foaming properties. In this study, the conjugated durian seed gum produced the most stable foam among all samples. On the other hand, the emulsion stabilized with the conjugated durian seed gum also showed more uniform particles with a larger specific surface area than the emulsion containing the non-conjugated durian seed gum. The conjugated durian seed gum showed significant different foaming properties, specific surface area, particle uniformity and water holding capacity (WHC) as compared to the target polysaccharide gums. The conjugated durian seed gum showed more similar functional properties to Arabic gum rather than other studied gums.

Quality improvement of baked products is becoming an awareness for a wide range of manufacturers and consumers. In the current study, optimization of final proofing time, FPT, (20–60 min), dough mixing time in low speed, MTLS, (63 rpm) and in high speed, MTHS, (180 rpm) for 2.05–8.05 min based on bread moisture content, water activity, specific volume, sensory quality factor, hardness, dough adhesiveness, cohesiveness, hardness, chewiness, stickiness, resilience features using response surface method was designed. Results indicated that a higher value of quality and sensory features as well as dough cohesiveness was achieved by FPT level. Increasing MTLS led to increase in dough adhesiveness, hardness, chewiness and bread hardness. Correlation results revealed that specific volume may be considered for bread hardness (r = −0.75) and dough stickiness (r = −0.81) prediction. The suitable mathematical model for staling kinetics was power model. The optimization results were 56.84-min FPT, 2.05-min MTLS and 7.69-min MTHS, and are useful for bread quality improvement. Practical Application This work presents a useful approach for shelf life, quality and sensory improvement of bread. Furthermore, the correlation results indicated that some bread simple features can be applied for prediction of bread shelf life and some batter attributes and can be used for study of dough and bread behavior.

Digital image processing technique is a useful tool for bread texture analysis. In the current study, to improve bread features (cell wall thickness, fractal dimension, circularity, solidity, crust lightness, crumb lightness, mean cell area [MCA], cell count and density, porosity, specific loaf volume [SLV], hardness and sensory attributes), final proofing time (FPT), dough mixing time in low (MTLS; 63 rpm) and high speed (MTHS; 180 rpm) were considered as the independent variables. Result showed rising FPT up to 60 min led to significant (P ≤ 0.05) enhancement of SLV and MCA up to 4.62 cm3/g and 4.63 mm2, respectively, and decrease in crust lightness, crumb lightness and hardness. Cell count and density were strongly affected by MTHS. Crust lightness may be presumably considered as an indicator for hardness (r = 0.767) and SLV (r = −0.843) prediction. The optimized conditions were 60-min FPT, 5.30-min MTLS and 8.05-min MTHS, which can be applied for large-scale production of bread. Practical Applications Generally, analysis of changes in quality, shelf life and sensory features of bread during bread-making process is time consuming. This research shows that survey of these properties can be carried out in quick time with correlation between image attributes and other characteristics. Furthermore, representative-optimized conditions are useful for improvement of bread quality factors.

Background Plants provide the probability of a strategy in exploration for new drugs. Infectious diseases, which account for the significant ratio of the health problems, are most frequently catered for by this system of medicine. Objectives The aim of this study is to investigate the antimicrobial effect of Biarum carduchorum (Kardeh) on Aspergillus fumigatus and Penicillium expansum in vitro. Materials and Methods In this experimental study the antibacterial activity of methanol and aqueous extracts of Biarum carduchorum against 2 laboratory strains of fungi (Aspergillus fumigatus and Penicillium expansum), were evaluated with using paper disk methods, Collins method, minimal inhibitory concentration (MIC) and minimum fungicidal concentration (MFC). Results The methanolic extract inhibited the growth of all tested microorganisms. The phytochemical analysis of the methanolic extract of B. carduchorum revealed the presence of phenolics (+++), alkaloids (+++), tannins (++), flavonoids (++), saponins (+), phlobatanins (+), anthraquinones (+), terpenes (++) and cardiac glycosides (+). The result showed that MIC of B. carduchorum leaves of the aqueous and methanolic extracts for P. expansum and A. fumigatus was 32, 8, 16, 4 mg/mL respectively. The aqueous and methanolic extracts MFC of B. carduchorum leaves for P. expansum was 64 and 32 mg/mL respectively. Conclusions The presence of antibacterial activity in different fractions indicates that the extract possesses different compounds, which have different activities. The result of this study suggests that the methanolic and aqueous extracts of B. carduchorum could be suitable for the treatment on the microorganisms associated with infections.

BACKGROUND: The objective of this study was optimisation of multiplex polymerase chain reaction (PCR) by a new primer set for simultaneous detection of ropiness agents as the main bacterial spoilage of Iranian bread. After inoculation of bread dough with activated Bacillus licheniformis (ATCC 9789) and Bacillus subtilis (ATCC 6633), DNA was extracted from the dough and subjected to PCR. Then simplex and multiplex PCR tests were optimised. RESULTS: From the results obtained, the optimum PCR conditions for simultaneous detection of the target genes in Bacillus species were an annealing temperature of 59 °C and an MgCl2 concentration of 2.5 mmol L−1. To design primers for these two bacteria, owing to close homology and the existence of similar conserved sequences in their 16S rRNA genes, lpaL and aprE genes (497 and 744 bp target sequences) respectively were chosen. Finally, by sequencing of PCR products, accurate and specific detection of the two desired Bacillus species was confirmed. The results were registered with GenBank under accession numbers HQ877873 and HQ871154. CONCLUSION: Compared with culture-dependent methods, this procedure offers significantly higher accuracy and speed, which are crucial criteria when it comes to food safety and high volumes of referred samples respectively. Copyright © 2012 Society of Chemical Industry

The effect of pretreatment osmotic–ultrasonic dehydration on the sorption isotherms of quince was determined by static gravimetric method at temperatures of 30 °C, 45 °C, and 60 °C. The curves obtained can be considered as type II according to the Brunauer–Emmett–Teller (BET) classification. Adsorption data were fitted into seven isotherm models. The best fit of the experimental data was obtained with Peleg for both fresh- and pretreated dried quince slices. Thermodynamic properties such as net isosteric heat, differential entropy, enthalpy–entropy compensation, and spreading pressure were determined from moisture adsorption isotherm data of quince. The net isosteric heat of sorption and differential entropy decreased with increasing moisture contents in an exponential function. A plot of differential heat versus entropy satisfied the enthalpy–entropy compensation theory. The spreading pressure increased with increasing water activity, and decreased with increasing temperature. The value of net isosteric heat, differential entropy and spreading pressure of untreated samples is higher than that of pretreated samples of quince.

Yogurt-ice cream is a nutritious product with a refreshing taste and durability profoundly longer than that of yogurt. The probiotic Lactobacillus acidophilus (La-5) cells either in free or encapsulated form were incorporated into yog-ice cream and their survivability were studied. Fructooligosaccharide (FOS) as a prebiotic compound at three levels (0, 4 & 8 % w/w) was added to yogurt-ice cream mix and its effects on some chemical properties, overrun and firmness of product were evaluated. The higher the incorporated FOS concentration, the lower were the pH value and higher the total solid content of treatments. FOS incorporation (8 %) significantly increased the overrun of treatments and reduced their firmness. The viable counts of free probiotics decreased from ~9.55 to ~7.3 log cfu/g after 60 days of frozen storage while that of encapsulated cells merely decreased less than 1 log cycle. Encapsulation with alginate microbeads protected the probiotic cells against injuries in the freezing stage as well as, during frozen storage.

Experiments were conducted to determine the effect of pretreatment osmotic– ultrasonic dehydration on the desorption isotherms of quince by static gravimetric method at 30, 45 and 60C temperatures. The isotherms exhibited type II behavior, with the sorption capacity decreased with increasing temperature. Out of the six equilibrium sorption models that were evaluated, the Peleg equation gave the best fit to the sorption data. The Hasley equation was further used to estimate the thermodynamic functions (such as net isosteric heat, enthalpy–entropy compensation and spreading pressure) of quince. The net isosteric heat of sorption and differential entropy decreased with increasing moisture contents in an exponential function. A plot of differential heat versus entropy satisfied the enthalpy–entropy compensation theory. The spreading pressure increased with increasing water activity and decreased with increasing temperature. The value of net isosteric heat, differential entropy and spreading pressure of untreated samples are higher than that pretreated sample quince.

In this study, application of a multi-objective optimization technique based on response surface methodology has been presented. Quince slices were dehydrated using osmotic dehydration with sucrose solutions at different concentration (40 and 60 Brix), processing time (1, 1.5, and 2 h), and ultrasonication time (0, 15, and 30 min) were the factors investigated with respect to water loss, solid gain, and weight reduction. Response surface methodology was used to determine the optimum processing conditions that yield maximum water loss and weight reduction and minimum solid gain during osmotic dehydration of quinces. Dehydrated quince slices at optimized osmo-ultrasound condition were then subjected to air-drying at 60 and 80 °C. Rehydration ratio, shrinkage, and moisture content of dried samples were regarded as responses to the non-thermal and air-drying conditions. Multi-objective optimization led to obtaining the best condition for production of dried quince slices with lowest moisture content, and shrinkage.

Glazing is a surface coating method for enhancement of the quality factors of bakery products. This study was intended to investigate the effect of different bakery glazing groups such as natural, polyols, sugars, and hydrocolloids on Barbari flat bread. Some quality attributes of bread such as moisture content, water activity, specific volume and width/height ratio (0 day) and hardness, crumb, and crust moisture (0–12 days) were evaluated. Results showed that vegetable oil treated samples had the lowest water activity and moisture content. Also, xanthan treatment provided the greatest effect on the specific volume of fresh bread, which enhanced it from 3.94 to 5 cm3/g. Vegetable oil, glycerol, dextrose, liquid glucose, and guar treatments had more significant effect on width/height ratio in comparison to nontreated (unglazed) bread. Evaluation of crumb hardness and moisture during 12 days storage implicated water, egg yolk, starch, and propylene glycol treatments were able to diminish the bread staling and these treated samples had the lowest crumb hardness. Crumb moisture of Barbari bread was affected mostly by water and starch treatments at day 12. Finally, our finding approved that using of glazing as a novel method is an effective technique for improvement of overall quality of flat bread and its application is suggested for large-scale production of other bakery products.

The retention and shelf stability of cardamom oil entrapped in freeze- and spray-dried microcapsules coated with skim milk powder and modified starch was investigated. It was found that the retention of flavor in freeze-dried matrices was low and independent from the composition of wall material, whereas for the spray-dried microcapsules, it was much higher and markedly dependent on the type and percentage of coating material. It was also shown that the particle size of spray-dried powder greatly contributed to the flavor retention and surface oil content of microcapsules. Additionally, microscopic observation of powder particles revealed that the type of wall material and drying method distinctly influenced the morphological characteristics of powders which presumably caused a difference in their capability of cardamom oil retention.

Pistachio (Pistacia vera) is a tree nut that has been reported to cause IgE-mediated allergic reactions. This study was undertaken to investigate the distinctions between different cultivars of pistachio nut and the influence of different processing on the IgE-binding capacity of whole pistachio protein extracts. The influence of different processes on allergenicity was investigated using competitive inhibition ELISA and Western blotting assays. The Western blotting results of extracts from pistachio cultivars showed no marked difference among them. The IgE-binding capacity was significantly lower for the protein extract prepared from steam-roasted than from raw and dry-roasted pistachio nuts. The results of sensory evaluation analysis and hedonic rating proved no significant differences in color, taste, flavor, and overall quality of raw, roasted, and steam-roasted pistachio nut treatments. The most significant finding of the present study was the successful reduction of IgE-binding by pistachio extracts using steam-roast processing without any significant changes in sensory quality of product.

This study introduces Alyssum homolocarpum seed gum, as a natural stabilizer for O/W emulsions. The droplets characteristics, flow properties and physical stability of ultrasonically prepared corn oil-in-water emulsions were investigated at various gum concentrations. The results indicated that for the freshly prepared emulsions, the mean diameter of droplets decreased significantly with an increase in gum concentration from 0.25% to 0.75%. Storage of emulsions for a period of 4 weeks resulted in an increase in the size of droplets, being substantially greater for the samples containing 0.25 and 0.5% gum and negligible for those prepared with 0.75 and 1.0% gum. Similar trend was observed for the specific surface area of droplets but in the opposite direction. Optical microscopy demonstrated that increasing the proportion of gum up to 0.75% reduced the extent of flocculation and coalescence and enhanced monodispersity. Newtonian and non-Newtonian shear-thinning flow behaviors were observed for emulsions prepared with 0.25% gum concentration and those containing higher concentrations respectively. Accordingly, faster creaming was found to be associated with the emulsions prepared with low gum concentration.

The influence of glycerol, sorbitol, maltitol and propylene glycol on shelf life and quality of Barbari, Iranian flat bread, fortified with soy flour, was examined. Effects of different levels of polyols (0, 1 and 5 g/100 g) were analyzed during 2 weeks of storage at room temperature. Specific volume and width/height ratio of fresh breads were not affected by polyol addition, while it significantly decreased the moisture content of the bread. Propylene glycol significantly decreased water activity to 0.871 (1 g/100 g propylene glycol) and 0.867 (5 g/100 g propylene glycol) in comparison with the control (0.883). Evaluation of crumb hardness and moisture indicated that sorbitol and propylene glycol were able to diminish bread staling. The rise in hardness in polyol-supplemented bread samples was not significantly more than the control between the first and second days of storage. Increase in hardness of bread samples was observed lower than the control after the second day in both levels of the sorbitol and 5 g/100 g propylene glycol. Acceptability of the breads, as indicated by panelists, was found to be higher than control bread for 5 g/100 g propylene glycol with 3.8 and 4.8 values, respectively. Results showed that propylene glycol can present the greatest effect on quality and shelf life of Barbari flat bread fortified with soy flour. PRACTICAL APPLICATIONS Flat bread plays a significant role in the diet of large portion of the Middle East population, but it is a highly delicate product. The three most common forms of bread deterioration are staling, moisture loss and microbial spoilage. One of the most frequent ways to prevent or control these problems is the use of additives such as polyols. Polyols may be a good choice to diminish the hardening phenomena, moisture loss and water activity, and increase the shelf life and sensory acceptability of bakery products. On the other hand, incorporation of soybean flour into food products, especially in developing countries, can provide good nutritional quality besides prolonging the shelf life of bread. The changes due to polyol addition need to be characterized if a viable commercial product should be achieved.

The probiotics, Lactobacillus acidophilus PTCC1643 and Lactobacillus rhamnosus PTCC1637, were encapsulated into uncoated calcium alginate beads and the same beads were coated with one or two layers of sodium alginate with the objective of enhancing survival during exposure to the adverse conditions of the gastro-intestinal tract. The survivability of the strains, was expressed as the destructive value (decimal reduction time). Particle size distribution was measured using laser diffraction technique. The thickness of the alginate beads increased with the addition of coating layers. No differences were detectable in the bead appearance by scanning electron microscopy (SEM). The alginate coat prevented acid-induced reduction of the strains in simulated gastric juice (pH 1.5, 2 h), resulting in significantly (P

Summary Basil seed (Ocimum basilicum L.) is cultivated in large quantities in different regions of Iran. This seed has reasonable amounts of gum with good functional properties which is comparable with commercial food hydrocolloids. A central composite rotatable design was applied to evaluate the effects of temperature, pH and water/seed ratio on the yield, apparent viscosity and protein content of water-extracted Basil seed gum. All of the variables significantly (P 0.05). Numerical optimisation determined the optimum extraction conditions based on the highest yield and viscosity and the lowest protein content as being temperature 68.71 °C, pH 8.09 and water/seed ratio 65.98:1. Power law model well described non-Newtonian pseudoplastic behaviour of BSG. Flow behaviour index (n) and consistency index (K) of 1% crude and pure BSG samples were 0.306, 0.283 and 17.46, 20.22 Pa sn, respectively.