Phenolic inhibitors involved in the natural fermentation of Gemlik cultivar black olives

Olive fruits of the Gemlik variety harvested from different regions of Turkey were placed in aseptic or non-aseptic brines containing 6 % NaCl. Olives of non-aseptic treatment were left to spontaneously ferment under anaerobic conditions. Samples for microbiological and chemical analysis were taken periodically during the course of the fermentation. No lactic acid bacteria growth was observed in three of the six samples, and yeasts were the prevailing microbial group in the other samples. Brines were analyzed for fermentable substrates (glucose, fructose, sucrose and mannitol), fermentation products (organic acids and ethanol) and phenolic–oleosidic compounds. Most of the unprocessed fruits had a low concentration of oleuropein. Hydroxytyrosol and oleoside 11-methyl ester were the main phenolic and oleosidic compounds in all brines. Likewise, the content of antimicrobials such as the dialdehyde form of decarboxymethyl elenolic acid, either free or linked to hydroxytyrosol, in brines was very low, which may permit the growth of lactic acid bacteria in these media. A growth test with two strains of Lactobacillus plantarum was applied to aseptic brines of all samples to determine whether these compounds inhibited lactic acid bacteria growth. The results of this study indicated that Gemlik olive is a “sweet” variety with a low antimicrobial compound content that can be fermented by lactic acid bacteria under favorable conditions.     

Degradation of organophosphorus pesticides in wheat during cookie processing

For investigating carryover of some organophosphorus pesticide residues in the cereal food chain from grain to consumer, a study was set up on wheat bran, flour and cookies, with and without bran. Special emphasis was given to malathion and chlorpyrifos-methyl residues in cookies for better protection of consumers. Pesticide-free wheat was placed in a small-scale model of a commercial storage vessel and treated with these pesticides. The residue levels of insecticides were determined in wheat, as well as in bran, flour and cookies produced from stored wheat at various time intervals during storage. A multiresidue analysis was performed using GC–NPD and GC–MS. Malathion and chlorpyrifos-methyl residue levels were higher than the maximum residue limits (MRLs) in wheat after 240 days of storage. MRLs established by the EC for malathion and chlorpyrifos-methyl in wheat are 8 and 3 mg kg⁻¹, respectively. The residue levels of insecticides in flour samples also exceeded the MRL (2 mg kg⁻¹ for both insecticides). Eight months of storage were not effective for reducing the residues in wheat to the levels below MRLs. Although, considerable amounts of the insecticides remained in the bran and flour, the cookie processing significantly reduced the concentrations in general. Chlorpyrifos-methyl was more persistent than was malathion and comparatively less degradation occurred during milling and cookie processing due to its physicochemical properties.     

Activated Carbon Addition to an Activated Sludge Model Reactor for Color Removal from a Cotton Textile Processing Wastewater

Color removal from cotton textile processing wastewater by addition of powdered activated carbon (PAC) into a lab-scale activated sludge system was examined. The activated sludge system was continuously operated in different sludge ages (SRTs) and hydraulic retention times (HRTs). SRT = 30?d and HRT = 1.6?d operation resulted in up to 36% color removal and 94% COD removal. PAC was added 100, 200, and 400 mg/L into the activated sludge system under these operating conditions. The results indicated that 100 mg/L PAC was sufficient to remove the maximum color measured (up to 50 m?1) from the wastewater. The addition of PAC did not affect chemical oxygen demand (COD) removal significantly. Oxygen uptake rate (OUR) tests were also performed to investigate the microbial activities controlling the system performance. The average OUR was 74.1 mg/L/h without PAC addition while it was 70 mg/L/h with PAC addition. Adsorbable organic halogens of the effluent wastewater decreased from 400 to 50 μg/L with the addition of PAC. Toxicity dilution factor decreased from 2 to 1.5 with the PAC addition into the activated sludge system.     

An overlooked complication of hemodialysis: Hoarseness

In hemodialysis patients, some degree of transient hoarseness may occur at the end of the dialysis, and it may be a wearisome, recurrent, and severe state for some hemodialysis patients. However, to date, it has not been a well‐defined complication of hemodialysis. The aim of this study was to state this complication and to throw light on it. Four hundred fifty‐nine hemodialysis patients were questioned about any change in voice quality during hemodialysis. The patients who had this complaint (n = 70) were included in the study, and the group of patients who suffered hoarseness (subgroup 1: severe, subgroup 2: moderate, subgroup 3: mild) were compared with each other and with the control group, which did not suffer hoarseness (n = 51). Hoarseness was found in 15.2% of the hemodialysis patients. The duration of their hoarseness was minumum 1 to maximum 24 hours. In the control group, coronary artery disease (P = 0.056), congestive heart failure (P = 0.049), autonomic neuropathy (P = 0.001), severe intradialytic hypotensive attacks (P = 0.000), heart valve abnormalities (P = 0.000), and left ventricular diastolic dysfunction (P = 0.000) were significantly lower than in hoarseness group. Older age (P = 0.024), coronary artery disease (P = 0.014), autonomic neuropathy (P = 0.011), and intradialytic hypotensive attacks (P = 0.0001), were associated with severe and moderate hoarseness. In the comparison of % change for systolic and diastolic blood pressure between the hoarseness subgroups, diastolic blood pressure change was not different (P = 0.521), but systolic blood pressure change was statistically lower in mild group than moderate (P = 0.033) and severe subgroup (P = 0.029). Dialysis‐induced hypotension may be the main contributor of transient hoarseness. Especially elderly and cardiovascularly compromised patients, who are vulnerable to rapid changes in volume status may experience it to serious extent and this complication may be mediated by autonomic nervous control related with volume depletion.     

Synthesis and properties of alkoxysilane-functionalized urethane oil/titania hybrid films

In this study, alkoxysilane-functionalized urethane oil/titania (AFUO/titania) hybrid films were synthesized by sol–gel method. For this purpose, alkoxysilane-functionalized urethane oil (AFUO) was first produced by the reaction of 3-aminopropyltriethoxysilane (APES) and partial glyceride (PG) mixture with toluene diisocyanate (TDI). Then, this intermediate was further reacted with titanium isopropoxide (TIP) by sol–gel process in thin films applied on a glass substrate. TIP content of the hybrid films were varied in the range of 5–20 wt.% in order to investigate optimum amount of TIP in view of film properties. The characterization of the hybrid films were done by FTIR, DSC, TGA and SEM analyses. FTIR and DSC analyses indicated the existence of Ti–O–Si bond. Film properties for coating purposes such as flexibility, adhesion, hardness, water, alkali and acid resistances were determined. Hybrid composite films showed better film properties in comparison with classical urethane oil.     

Hot air dehydration of figs (Ficus carica L.): drying kinetics and quality loss

The dehydration of fruit from fig trees is normally achieved by sun drying. There is concern about the safety of the end product, mainly because there is a risk of the development of aflatoxins. These concerns can be overcome by artificial drying (oven dehydration). Fig fruits of a local cultivar, which were either pre‐treated by blanching or blanching plus sulphuring or not treated at all, underwent hot air dehydration under mild processing conditions in a pilot airflow cabinet dryer. Sampling was carried out at regular intervals to calculate the rate of dehydration and assess quality changes. Microbiological counts and nonenzymatic browning were also monitored. Pretreatments resulted in a shorter processing time, compared with control fruits. In general, a falling dehydration rate period was observed. A dramatic loss of ascorbic acid was recorded, while an informal sensorial assay of the dried fruits gave a positive assessment.     

An Investigation in the Use of Ozone Gas in the Bleaching of Cotton Fabrics

Ozone, composed of three atoms of oxygen, can be used to oxidize many inorganic and organic impurities. Because of its high oxidizing capacity, the opportunities and parameters of ozone gas use in bleaching of cotton fabrics were researched in this study. It was found that in a very short time cotton fabrics can be bleached if the water content of cotton-woven fabric was 60% and the pH of the water impregnated was 7. Moreover, ozonation at room temperature was shown to be more efficient than ozonation at high to medium temperatures.     

Behaviour of some organophosphorus pesticide residues in peppermint tea during the infusion process

In order to investigate dissipation behaviour of malathion, fenitrothion, dimethoate, chlorpyrifos and pirimiphos-ethyl during the infusion process, pesticide-free dried peppermint leaves were spiked with the pesticides. Infusions were prepared according to the usual process of infusion preparation. The effect of the infusion process on the transfer of the pesticides from the spiked peppermint leaves into brew was examined at intervals of 5, 10, 15 and 20 min. Residues were determined using a gas chromatograph equipped with a flame ionisation detector (FID). The decrease in pesticide levels during infusion was found to be statistically significant (p < 0.05). Transfer of residues decreased significantly with infusion time. The carryover of the residues of dimethoate, which has the highest water solubility, into the infusion was the highest. Satisfactory relationships were found between water-solubility (Ws), partition coefficient (K_ow) and Henry’s law constant (H) of the pesticides with the transfer of pesticides to brewed tea. It was observed that not only water solubility or K_ow but also H controls the dissipation of the pesticides from water or their air–water partitioning.