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关键词： Food waste   Msayer   Texture   Volatile composition   Consumer study  

摘要： A traditional fermentative process typical of North-African countries has been used to develop a new product using orange peels discarded from orange juice making. The impact of different NaCl (5-10-15%), sucrose (3-45%) and time (40-65-90 days) conditions on the physicochemical characteristics of the final product (instrumental texture, color, volatile composition) has been analyzed in the present research. Also, consumers' perception, as well as the making process (pH, total soluble solids, sugars, and Plate Count Agar method - PCA) has been studied. Results showed that the main effects and interactions affecting the process were 'NaCl content', 'time', and 'NaCl*time'. Although PCA was not significantly different among samples, pH, sugars content, instrumental texture, and volatile composition of the samples suggested a greater transformation in those samples fermented in a 5%-NaCl brine. A higher glucose and fructose consumption and polyalcohols generation, a faster decrease in pH, and a more complex volatile profile (higher alcohol and esters content), suggested that the fermentation process was faster when the NaCl content was low. In addition, although liking was similar for all samples, consumer study results showed that the sample made using a 5% NaCl content could be the one with the best potential success.

关键词： DNA binding   experimental studies   silver(I) complex   theoretical studies molecular docking and cytotoxicity  

摘要： Four silver(I) (Ag(I)) complexes: ***6, ***6, ***4 and ***4 of bis(methyl)thia salen (1) and bis (methyl)selena salen (2) with two different counter anions (PF6- and ClO4-) have been investigated for DNA binding properties. In vitro interactional association between the Ag(I) complexes and ct-DNA has been examined by performing spectroscopic titrations on absorption spectrophotometer and fluorescence spectrophotometer. A competitive binding study has also been done using a fluorescence spectrophotometer with ethidium bromide as a classical intercalator. The spectroscopic methods revealed a major groove. Viscometry and agarose gel electrophoresis experiments have also been performed as physicochemical methods to confirm the binding of complex molecules with DNA. Molecular docking analysis has been executed to obtain the theoretical insight into the mode of binding. The docking study demonstrated the major groove binding of all four complexes to the DNA with electrostatic metal-phosphate interactions (between the metal and the backbone of DNA) and hydrophobic interactions. Cytotoxicity of the complexes has been studied on the Human Fibroblast foreskin (HFF) cell line. The cytotoxicity results showed positive gesture for moving ahead to the next level of screening;the values were above 10 mu M which are appreciated for the normal cell lines.

关键词： Conservolea variety   Green olives   Halkidiki variety   lactic acid bacteria diversity   Spanish‐   style processing   yeast diversity  

摘要： The microbiological and physicochemical changes of industrially fermented Halkidiki and Conservolea green table olives were determined. Samples were analysed to monitor the population of lactic acid bacteria (LAB), yeasts and Enterobacteriaceae, together with changes in pH, acidity, salinity, colour, lactic acid, acetic acid and ethanol. LAB and yeast species diversity was evaluated at the beginning (1 day), middle (75 days) and final (135 days) stages of fermentation by RAPD-PCR genomic fingerprinting. Results revealed vigorous lactic acid processes as indicated by the dominance of LAB over yeasts. No Enterobacteriaceae could be detected after 30 days. Lactiplantibacillus plantarum (formerly Lactobacillus plantarum) dominated in the beginning of fermentation in both varieties. In the end, Lactiplantibacillus pentosus (formerly Lactobacillus pentosus) and Pediococcus ethanolidurans prevailed in Halkidiki and Conservolea varieties, respectively. As for yeasts, Kluyveromyces lactis/marxianus and Pichia manshurica prevailed at the onset of fermentation in Halkidiki and Conservolea varieties, whereas in the end Pichia membranifaciens dominated in both varieties.

关键词： Polyphenol oxidase   Enzyme activity   Structure   Physico-chemical properties  

摘要： The primary aim of this study is to investigate the impact of intensive pulsed light (IPL) on the activity, structure, and physico-chemical properties of polyphenol oxidase. The results showed that the lower the concentration of PPO, the lower the intensity and fluence required inactivating 90% of PPO. With the increase of the IPL fluence, the content of alpha-helix and beta-turn decreased by 57.6% and 22.5%, and the content of beta-fold and random curl increased by 58.2% and 69.0%, respectively. The endogenous fluorescence intensity decreases, which proves that IPL effectively inactivates PPO by destroying the secondary and tertiary structure of PPO. Surface hydrophobicity, free sulfhydryl content, aggregation index, and turbidity increased by 191.0%, 24.3%, 23.5%, 151.7%, respectively. The atomic force microscopy (AFM) results showed that the height distribution increased from 3 to 8 nm to 12-16 nm as the fluence increased, and the surface roughness decreased. This research provides a theoretical basis for applying IPL technology in inhibiting endogenous enzyme activity in food and controlling the browning of fruits and vegetables.

关键词： Oxidised nanocellulose   Sugar alcohols   Rheology   Tensile properties  

摘要： Oxidised nanocelluloses have previously shown promise for the production of extruded filaments with high tensile strength properties. However, they also exhibit poor wet strength due to swelling upon immersion in water. This has resulted in the use of chemical cross-linkers, or co-extrusion with multivalent cations, or cationic polymers, to inhibit this. Here, we report on the effect of incorporating sugar alcohols (glycerol, sorbitol and maltitol) in an oxidised nanocellulose gel before extrusion. Whilst their presence weakens the initial gel, they enable the continuous wet spinning of filaments that are stable in aqueous media without the need for post extrusion processing. We conclude that the relative hydrophilicity of the sugar alcohol and its ability to protonate surface carboxyl groups upon drying are key parameters regarding the physicochemical effects observed.

关键词： Fermented sausage   Traditional practice   Composition   Fatty acid   Biogenic amine  

摘要： Three Serbian traditional dry-fermented sausages,Sremski kulen(S),Lemeski kulen(L) andPetrovacka kobasica(P), were compared for physicochemical, biochemical and microbiological properties, in order to provide complex overview of their quality and safety. The sausages were produced and analyzed within two production seasons in traditional practice. Water activity, color, texture and proximate composition varied significantly (P < 0.05), particularly due to moisture, protein and fat content, what indicated differences in basic formulation of raw sausage mixture, type of casing and some technological procedures. Based on the fatty acid profile the most favorable PUFA/SFA ratio was obtained in sausage P (0.68), while the obtained results for acid value (15.2-22.4 mg KOH/g lipid) and TBARS value (0.27-0.55 mg malondialdyde/kg) indicated low level of lipid degradation and oxidation in all samples. Regarding the microbial and biogenic amines (BA) analysis, positive outcome of this research is the total absence of all pathogenic microorganisms examined, while the registered levels of BA showed a great variability among the sausages. In particular, total BA content in L attained level that is approx. 50% higher than the recommended one. Hence, special care should be implemented regarding the future production and consumption of this type of sausage. Overall results of this study may be useful to define complete distinctive features of these sausages, to determine relations among them, as well as to improve some phases of traditional manufacturing process.

关键词： coordination compounds   iron(II)   4-amino-1   2   4-triazole   2-naphthalenesulfonate   spin crossover   spectrophotometry   conductometry   cyclic voltammetry  

摘要： Physicochemical properties of the iron(II) 2-naphthalenesulfonate complex with 4-amino-1,2,4-triazole ([Fe(NH(2)trz)(3)](ns)(2)center dot 2H(2)O (I)) are studied. The complex exhibits the (1)A(1) <-> T-5(2) spin crossover. Complex I and the initial compound for its preparation, Fe(ns)(2) (II), are studied by static magnetic susceptibility, conductometry, spectrophotometry, and cyclic voltammetry methods. The mu(eff)(T) dependence for I shows that the spin transition is abrupt both in the initial complex and in the DMF solution. Forward and inverse spin crossover temperatures are determined.

关键词： Microalgae biomass   Functional properties   Bioactive terpenes   Bioresource technology   Protein folding  

摘要： This study aimed to evaluate the functionality of bioactive terpenes on Spirulina (Arthrospira platensis;AP) and Chlorella (Chlorella vulgaris;CV) biomasses. The two microalgae species were treated with 0.01%, 0.05%, and 0.1% of thymol (THY), trans-cinnamaldehyde (TC), menthol (MEN), and vanillin (VAN). Raman microspectroscopy (RMS) was correlated with other physicochemical methods to confirm their functional mechanisms. In results, THY (0.1%) decreased (P < 0.05) RMS intensity at 1196 cm-1 that represents the protein's secondary amines wavenumber. Also, VAN (0.1%) decreased significantly A. platensis alpha-helix to 16.60 +/- 0.52% compared to the control with 19.83 +/- 0.32%. While, 0.1% TC increased (P < 0.05) the viscosity to 2.52 +/- 0.61 Pa.s. This work demonstrated that terpenes could differently affect the physicochemical structure of microalgae biomass. The RMS's uniqueness comes from its ability to evaluate the functionality of terpenes during microalgae cultivation. Besides, chemometrics led to focus on the most important variances.

关键词： Anchote starch   Amylose   Morphological and pasting properties   FTIR   XRD  

摘要： Starch is a polysaccharide that has an important role in food and other industries. Anchote, a local name for "Coccinia abyssinica" is an indigenous tuber crop to Ethiopia supposed to contain considerable amount of starch. This study aims to extract starch from this plant using sodium metabisulfite (0.025, 0.075 and 0.125% w/v), sodium chloride (0.5, 1.0 and 1.5 M) and water. Anchote starch extracted by using 0.075% (w/v) sodium metabisulfite has presented the highest extraction yield (75.56%) on a dry weight basis. The values of moisture content, bulk density and amylose content of anchote starch were recorded as 11.6%, 0.51 g/mL and 32.14%, repectively. The color of anchote starch was measured in L*, a*, b* values and obtained 89.80, 0.025, 3.63, respectively and whiteness was 89.16%. Its granular shapes exhibited polygonal, semi-oval with some round. The swelling power and the solubility of anchote starch were ranged from 2.15 to 10.6 g/g and 0.51-19.15% respectively. Syneresis of anchote starch increased when pastes were stored at low temperatures and decline in paste clarity upon storage. Anchote starch exhibited gelatinization temperature;onset, peak and conclusion (68.94, 74.99 and 84.87 degrees C) respectively. Pasting properties of anchote starch;peak, trough, breakdown, final and setback viscosities were recorded as 4879 cP, 2101.7 cP, 2777 cP, 5636.1 cP, 3535 cP, respectively. Anchote starch showed type B crystalline pattern with 39.15% relative crystallinity. FTIR spectra of anchote starch bands were almost similar with potato starch. The results indicate that this starch may be an alternative source for the production of industrial products that may require starch.

关键词： myofibrillar proteins   quality changes   thawing methods   Trachinotus ovatus  

摘要： The effects of five thawing methods (ultrasonic thawing [UT], radiofrequency thawing [RFT], water immersion thawing [WIT], microwave thawing [MT], and cold storage thawing [CST]) on physicochemical properties, water migration, and protein characteristic of whole frozen pompano (Trachinotus ovatus) were investigated and compared with fresh samples (FS). The physicochemical changes of thawed pompano were analyzed based on pH, total volatile basic nitrogen (TVB-N), color difference. The protein aggregation, physicochemical properties and conformation of myofibrillar proteins (MPs) were evaluated by Sodium dodecyl sulfate polyacrylamide gel electrophoresis, differential scanning calorimetry, and Raman spectra, respectively. Water migration and MPs microstructure were measured by low-field nuclear magnetic resonance (LF-NMR) and scanning electron microscope (SEM), respectively. The results showed that different thawing methods could accelerate the protein denaturation and decrease of quality in pompano, especially MT treatment causing more seriously local overheating phenomena. Among the samples with different thawing treatments, the changes of pH, TVB-N values, and color difference in RFT and UT were closed to that from FS. The MT had the shortest thawing time, but could produce the damage of structural muscle. RFT had desirable thermal stability and made the protein secondary structure more stable, the myofibril bundles were also straight and smooth by SEM observation. The content of bound water and free water had no significant changes by LF-NMR. Therefore, compared with other thawing methods, RFT is a desirable thawing method for maintaining the quality of thawed pompano. Practical applications Before further processing of frozen pompano, the thawing process is an important part, which is highly associated with the quality of products. The damage of conformation and properties in aquatic protein caused by freeze-thaw process is very obvious in food processing industr