Effect of maturation conditions on sensory and antioxidant properties of old Serbian plum brandies

?ljivovica and Prepe?enica are traditional Serbian distillated beverages made from varieties of plum, of the genus Prunus. The ageing in wooden casks not only improves the sensory characteristics, but also changes the content of total polyphenols and contributes to the other important health properties, such as the increase of their antioxidant capacity. In this study, home-made brandy (?ljivovica and Prepe?enica) samples were used, which matured in casks during the time period from 10 to 47?years. The aim of this investigation was to examine the influence of the ageing parameters (time period and type of wooden casks) and raw material (plum cultivars) on the total polyphenol content, amount of certain phenol compounds, sensory properties, colour and antioxidant properties in matured brandies. The individual phenol components were determinated using HPLC system equipped with diode array detector, while the total phenol content and antioxidant activity was estimated using spectrophotometric methods (Folin?CCiocalteu, DPPH, FRAP and TEAC). Total polyphenol content (TPC) of aged Prepe?enica samples was ranged from 230.26 to 890.26?mg/L gallic acid equivalents (GAE mg/L), whereas the TPC of ?ljivovica sample was 110.38?mg/L. Antioxidant capacity of analysed Prepe?enica samples and ?ljivovica sample was in strong correlation with TPC. Total sensory score of all samples was very high and varied between 18.2 and 19.8. The obtained results have shown that the benefit of longer maturation on sensory characteristics is well recognized, but the improvement has some limitation.     

FGF10 inhibits dominant follicle growth and estradiol secretion in vivo in cattle

Fibroblast growth factors (FGFs) are involved in paracrine control of follicle development. It was previously demonstrated that FGF10 decreases estradiol (E(2)) secretion in granulosa cell culture and that theca cell FGF10 mRNA expression is decreased in healthy follicles from abattoir ovaries. The main objectives of this study were to evaluate FGF10 and FGFR2b mRNA expression during follicular development in vivo, to evaluate the effect of FGF10 on follicle growth using Bos taurus taurus cows as a model, and to gain more insight into the mechanisms through which FGF10 inhibits steroidogenesis. Messenger RNA encoding both FGF10 and FGFR2b (main FGF10 receptor) was significantly more expressed in subordinate follicles (SFs) than in dominant follicles (DFs). The intrafollicular injection of FGF10 into the largest growing follicle at 7-8?mm in diameter interrupted the DF growth in a dose-dependent manner (11±0.4, 8.3±1 and 5.9±0.3?mm for 0, 0.1, and 1?μg/ml FGF10, respectively, at 72?h after treatment; P<0.05). In a third experiment, follicles were obtained 24?h after FGF10 (1?μg/ml) or PBS treatment through ovariectomy. In theca cells, FGF10 treatment did not affect mRNA encoding steroidogenic enzymes, LHCGR and IGFBPs, but significantly upregulated FGF10 mRNA expression. The expression of CYP19A1 mRNA in granulosa cells was downregulated by FGF10 treatment, which was accompanied by a 50-fold decrease in E(2) production, and decreased cyclin D2 mRNA. These results have shown that FGF10 and its receptor FGFR2b are more expressed in SFs and provide solid in vivo evidence that FGF10 acts as an important regulator of follicular growth in cattle.     

Changes in polyphenolic content and antioxidant activity after thermal treatments of grape seed extract and grape pomace

This study was undertaken to investigate the effect of heat treatment on polyphenolic content and antioxidant activity in grape pomace (GP) and grape seed extract (GSE). GP and GSE were heat treated in a furnace or autoclaved at 100 °C for 15, 30 and 60 min. Structural modifications of the polyphenols during thermal processes were determined by HPLC–MS, and the antioxidant activity was determined by ABTS, DPPH and photochemiluminescence methods. In general, furnace thermal treatment of GSE and GP did not affect the total extractable polyphenols content, tannin content, procyanidin components and the antioxidant activity. Autoclave treatment caused an extensive hydrolysis of gallocatechin (70%), catechin (61%), epicatechin (65%), procyanidin B1 (75%) and procyanidin B2 (73%) in GSE, and an increase in gallic acid (71%), gallocatechin (100%) and epicatechin gallate (129%) in GP. Autoclave treatment did not affect the antioxidant activity of GSE or GP. It can be concluded that the effect of autoclave was more severe than furnace heat treatment modifying the phenolic profile in a different manner depending on the grape seed product used. These modifications were not related with changes in antioxidant activity.     

Dynamic monitoring of the shelf life of Cobia (Rachycentron canadum): a study on the applicability of a smart photochromic indicator

To ensure the marketing of fresh fish‐based products, it is necessary to develop fast methods that assess its freshness in real time. This study therefore evaluated the applicability of a photochromic time–temperature indicator (TTI) to monitor the time and temperature history during the period of validity of the whole fish of the cobia specimen stored in ice. The TTI response was both visibly interpreted as well as adaptable to measurement using suitable equipment. The results showed that the smart indicator activated during 6 s of ultraviolet light showed a similar rate of deterioration of the analysed product visual response, proving to be a dynamic shelf life indicator that can assure consumers the ultimate quality point of the entire cobia easily, cheaply and accurately.     

Effect of the cultivation mode on red pigments production from Monascus ruber

In submerged cultures performed in chemically defined fermentation medium containing glucose and glutamate, the growth and production of water‐soluble red pigments and citrinin by the filamentous fungus Monascus ruber were studied under various carbon/nitrogen (C/N) ratios. The specific production of the red pigments was optimal at a glucose/glutamate ratio of about 10 and then steadily decreased at higher C/N ratio. In contrast, the production of the mycotoxin increased with increased C/N with an optimum in the range of 30–45. In a fed‐batch mode, it was also found that the production of pigments was not favoured in fed‐batch mode by feeding the medium with glucose while keeping the C/N ratio lower than 10. This low production likely resulted from concurrent high accumulation of L‐malic acid that was reported to inhibit this production. In contrast, this mode of cultivation was rather favourable for the production of the mycotoxin.     

Rheological properties of reduced-fat and low-fat ice cream containing whey protein isolate and inulin

Instrumental analyses were used to evaluate the rheological properties of regular (10%), reduced-fat (6%) and low-fat (3%) ice cream mixes and frozen ice creams stored at −18 °C. The reduced-fat and low-fat ice creams were prepared using 4% whey protein isolate (WPI) or 4% inulin as the fat replacement ingredient. The composition, colour, apparent viscosity, consistency coefficient, flow behaviour index, hardness and melting characteristics were measured. No effect of WPI or inulin was obtained on the colour values. Compared with regular ice cream, WPI changed rheological properties, resulting in significantly higher apparent viscosities, consistency indices and greater deviations from Newtonian flow. In addition, both hardness and melting resistance significantly increased by using WPI in reduced-fat and low-fat ice creams. Inulin also increased the hardness in comparison to regular ice cream, but the products made with inulin melted significantly faster than the other samples.     

Coagulase-negative staphylococci species affect biofilm formation of other coagulase-negative and coagulase-positive staphylococci

Coagulase-negative staphylococci (CNS) are considered to be commensal bacteria in humans and animals, but are now also recognized as etiological agents in several infections, including bovine mastitis. Biofilm formation appears to be an important factor in CNS pathogenicity. Furthermore, some researchers have proposed that CNS colonization of the intramammary environment has a protective effect against other pathogens. The mechanisms behind the protective effect of CNS have yet to be characterized. The aim of this study was to evaluate the effect of CNS isolates with a weak-biofilm phenotype on the biofilm formation of other staphylococcal isolates. We selected 10 CNS with a weak-biofilm phenotype and 30 staphylococcal isolates with a strong-biofilm phenotype for this study. We measured biofilm production by individual isolates using a standard polystyrene microtiter plate assay and compared the findings with biofilm produced in mixed cultures. We confirmed the results using confocal microscopy and a microfluidic system with low shear force. Four of the CNS isolates with a weak-biofilm phenotype (Staphylococcus chromogenes C and E and Staphylococcus simulans F and H) significantly reduced biofilm formation in approximately 80% of the staphylococcal species tested, including coagulase-positive Staphylococcus aureus. The 4 Staph. chromogenes and Staph. simulans isolates were also able to disperse pre-established biofilms, but to a lesser extent. We also performed a deferred antagonism assay and recorded the number of colony-forming units in the mixed-biofilm assays on differential or selective agar plates. Overall, CNS with a weak-biofilm phenotype did not inhibit the growth of isolates with a strong-biofilm phenotype. These results suggest that some CNS isolates can negatively affect the ability of other staphylococcal isolates and species to form biofilms via a mechanism that does not involve growth inhibition.     

Investigating the effect of production process of ball mill refiner on some physical quality parameters of compound chocolate: response surface methodology approach

Chocolate compound was produced using ball mill refiner, and the effect of agitator shaft speed and refining time on the physical quality parameters (particle size, colour and steady‐state rheology) of compound chocolate was determined using response surface methodology. The shaft speed and refining time range were selected between 40–60 r.p.m. and 10–30 min, respectively. Determination coefficient of the models established for particle size, Newtonian viscosity and colour parameters (brightness, chroma and hue angle) were found to be very close to unity. Increasing shaft speed and time induced a reduction in particle size and an increase in viscosity of the samples. Temperature sweep test was also performed, and the obtained data were successfully fitted to Arrhenius equation to calculate the corresponding parameters representing temperature dependency of the compounds. The results highlighted that the establishment of such models can provide essential information in terms of optimisation of production processes regarding usage purpose of the compound chocolate.     

Qualitative improvement of catfish burger using <Emphasis Type="Italic">Zataria multiflora</Emphasis> Boiss. essential oil

This study investigates the effects of different concentrations of Zataria multiflora Boiss. essential oil on the quality of catfish burger during storage at 4?°C. For this purpose, fish burgers were produced with 0, 0.2 and 0.4?% ZMEO and the changes in their TBA, PV, FFA, TVB-N, microbiological loads and appeal to consumers during storage were evaluated. The obtained results indicated that the best sensory quality was attained at the highest ZMEO concentration (0.4?%) compared with control samples. The storage time significantly affected the TBA, PV, FFA, TVB-N values, as treated samples with ZMEO showed lower values of lipid oxidation products compared with the control samples. Regarding to microbial load, samples treated with 0.2 and 0.4?% of ZMEO revealed significant reduction at 9th day of storage as compared with the control samples.