The possibility of fipronil pesticide electrochemical determination assisted by cobalt (III) oxyhydroxide was determined in this study. The redox pair CoO(OH)/CoO2 was used in this process. The correspondent mathematical model was developed and analyzed by means of linear stability theory and bifurcation analysis. It was shown that the oxyhydroxide may be applied as an efficient electrode modifier in the detection of fipronil in neutral and lightly alkaline media. Electrochemical response was clear and easy to interpret. The possibility of oscillatory and monotonic instabilities was also verified.

Bacillus sphaericus is a biopesticide that is highly effective for the control of mosquitos under harsh conditions such as polluted areas and UV light. In addition to its bioactivity, it produces proteases. In this present study, the composition of media comprising corn steep liquor (CSL) and molasses was optimised using response surface methodology (RSM) with a central composite design (CCD). Four different scenarios were arranged involving sole biopesticide and protease optimization (Scenarios 1 and 2), biopesticide optimization with protease as a by-product (Scenario 3) and protease optimization with biopesticide as a by-product (Scenario 4). The optimization of the simultaneous production of biopesticide and protease was not satisfactory to obtain large amounts of both products; however, when the production aim was a sole production with a by-product, optimal working conditions could be achieved. Also, according to industrial view, Scenario 1 is the only possible process for large scale systems.

Key Words:Bacillus sphaericus, Biopesticide, Protease, Response surface methodology (RSM), Molasses, Corn steep liquor (CSL)

Extraction yield and product quality of olive oil depend on various factors, particularly fruit’s maturity and processing methods. In this present study, kneading process was optimized by response surface methodology in terms of oil yield and quality parameters. As a sample, olive fruits were used at two different maturity stages (purple versus black stages). Prediction of response was proposed with a full quadratic second order regression equation, and regression parameters were checked for each model in order to evaluate model’s adequacy. Proposed models for yield and some quality parameters of olive oil were good enough for a successful prediction of experimental results. Oil yield was maximized as free acidity and peroxide value were controlled under the specified corresponding values for “extra virgin olive oil”. Optimal kneading conditions for oil production were at 30°C for 45 min for purple fruits and 28°C for 55 min for black counterparts.

Key Words:Olive oil, Physicochemical properties, Oil yield, Statistics, Modelling

The aim of this study was to determine physicochemical and microbiological properties of sucuk produced with different heat treatment temperatures. The effect of heat treatment at 60 (for 15 minutes), 65 (for 10 minutes) and 70°C (as reached) on chemical (pH, moisture, fat, protein, salt, ash, free fatty acidity, thiobarbituric acid reactive substances, residual nitrite, nitrosomyoglobin, total pigments, nitrosomyoglobin conversion ratio), physical (L*, a*, b*, nitrozation, discolorization), microbiological (total mesophilic aerobic bacterial counts, Staphylococcus and Micrococcus counts and lactic acid bacteria counts) and sensory quality characteristics of heat treated sucuk were investigated. Results were compared with traditional sucuk samples produced under commercial conditions. Heattreated sucuks were fermented for 3 days and traditional ones were fermented for 9 days under controlled conditions. Significant differences in physicochemical and sensory properties of produced sucuks were observed during production. The overall quality attributes of traditional sucuk were different in comparison to heat treated sucuks. Decreases in residual nitrite, nitrosomyoglobin and total pigment amounts in heat treatment process were determined. Nitrosopigment transformation ratio increased; however, in terms of physicochemical, microbiological and sensory properties, heat treatment at 60°C for 15 minutes resulted in sucuk samples with better acceptability.

Key Words:Heat treatment, Temperature, Sucuk, Physicochemical characteristics

High performance liquid chromatography (HPLC) system was used to determine phenolic contents of dietetic tea samples (n=10) marketed in Turkey. The most abundant phenolic compounds were gallic acid (ND–6.98 mg/100 g dw), protocatechuic acid (0.98–45.61 mg/100 g dw), 4-hydroxybenzoic acid (ND–31.56 mg/100 g dw), chlorogenic acid (ND–0.73 mg/100 g dw), caffeic acid (11.27–154.55 mg/100 g dw), p-coumaric acid (ND–6.56 mg/100 g dw), ferulic acid (ND–1.13 mg/100 g dw), ellagic acid (0.10–1.76 mg/100 g dw), epicatechin (7.59–290.07 mg/100 g dw), rutin (ND–49.95 mg/100 g dw) and quercetin (1.15–10.50 mg/100 g dw). Based on the results of this study, sensitivity and accuracy were good. Calibration curves had a good linearity for all compounds (r2>0.999). The quantitation limit ranged 0.010 to 0.050 µg/g in dietetic tea products. Recoveries were in the range of 86.45-97.35%. Results had good accuracy and reproducibility.

Key Words:Phenolic compound, Dietetic tea, HPLC.

Drying behaviour of apple slices in carbon fiber assisted cabin dryer (CFACD) was investigated, and performance evaluation of the process was conducted. The compatibilities of fourteen different thin layer drying models to the experimental data were examined. The highest corrected coefficient of determination, the lowest reduced chi-square and the lowest root mean square error were chosen as the model compatibility criterion. "Diffusion approach" model was determined as best model describing the drying behavior. Effective diffusion coefficient (D_eff) was found between 2.06x10_-10 and 4.56x10_-10 m²/s. For the temperature between 60-80°C, energy efficiency was in the range of 10.51- 13.12% while exergy efficiency values were between 9.44-11.64%. The specific moisture removal rate of apple slices in KFKK was found as 4.44*10_-5±0.00, 4.85*10_-5±0.00, 5.63*10_-5±0.00 kg removed water/kJ for the drying temperatures of 60, 70 and 80°C, respectively.

Key Words:Carbon fiber, Drying, Apple, Energy-exergy.

In this study, the physicochemical and microbiological characteristics of kefir produced from homogenized milk at four different pressures (15, 15/5, 30 and 30/5 MPa) in single-stage or two-stages were determined. Kefirs were stored at 4°C for 30 days. Dry matter, ash, fat and protein contents of samples were determined on the first day of storage while pH, titratable acidity and rheological and microbiological properties of samples were determined on the 1^st, 15^th and 30^th days of storage. Moreover, particle sizes were determined in milk homogenized at different pressures. With an increase in the homogenization pressure and stage, the D[4,3] (µm) and D[3,2] (µm) values of milk samples increased while their specific surface area values decreased. At the end of the storage period, pH, viscosity, thixotropy and consistency coefficient values, lactobacilli, lactococci, total mesophilic aerobic bacteria and yeast counts decreased in kefir samples. The highest viscosity, thixotropy and consistency coefficient values were determined in samples produced at 15 MPa in a single-stage, and the highest counts of lactobacillus, lactococcus and yeast were in samples produced with non-homogenized milk.

Key Words:Particle size, Homogenization, Kefir.

In recent years, the relationship between nutrition and health has been clearly presented in the light of scientific studies. Recently, consumers have been demanding for healthier foods; therefore, organic (ecological) agriculture and organic food applications have emerged to meet this demand. Organic hazelnut production has limited and its agriculture tends to increase gradually in recent years. In this study, various pomological analyses were carried out on samples belonging to Tombul, Foşa, Sivri, Çakıldak, Mincane and Palaz varieties of commercial importance grown in the Black Sea Region of Turkey (Trabzon, Ordu, Samsun and Düzce cities) where organic and conventional hazelnut production was located. Results indicated that conventional samples had higher values in terms of nut width, kernel length, kernel width, kernel thickness, nut weight, kernel weight and shell thickness values. There was no difference in nut length, nut thickness, internal cavity, kernel percentage, good kernels and the rate of defected kernel between two types of hazelnuts.

Key Words:Hazelnut, Physical properties, Nut quality, Corylus avellana L., Black sea region.

With the increasing trend of consumers towards healthier products in order to be able to live a better life, the demand for functional foods is also increasing day by day. When functional food groups consumed in various countries are considered, milk and dairy products are usually at the top of the list, and accordingly, the number of studies aiming to give functional properties to milk and dairy products are also quite high. Among these products, ice cream is also important because its nutritional value is high and the composition is one of the milk products that can be modified most easily. When studies on functionalization of ice cream are reviewed, it is seen that various researches have been carried out on enhancing the product more probiotic and prebiotics, whey, dietary fibers, omega-3 fatty acids and minerals enrichment, reducing fat and / or sugar content and increasing antioxidant capacity. The amount of ice cream consumed per capita in Turkey is increasing gradually, and this shows that the work to be done on functional ice cream will also be intensified. In this study, researches on the production of functional ice cream were reviewed.

Key Words:Functional food, Ice cream, Health.

Enzymes obtained from different sources and made ready for further use, which also coagulate caseins, are called milk coagulant enzyme, cheese rennet or rennet. For thousands of years, rennet (in general rennin/chymosin) from the abomasus section in stomachs of young ruminants animals has been obtained, and it has been used as milk coagulant in cheese making. As cheese production and consumption in the world have been increasing gradually, the steady declining supply of calf rennet has accelerated the acquisition of enzymes that can be used in place of alternative sources of calf rennet, and the search for highly efficient production methods has become compulsory. Studies on alternative sources for calf rennet are categorized as (i) the coagulants obtained from herbal sources (herbal rennet), (ii) the rennet source, the microbial cheese rennets consisting of proteolytic enzymes and obtained directly from microorganisms (microbial rennet), (iii) the transfer of genetic material responsible for rennin enzyme production to certain microorganisms, (recombinant chymosin), which is composed of enzymes identical to the renin enzyme that it produces. Recombinant chymosin is rapidly becoming a subject of research together with developing gene technology. In this review, the effects of animal, plant and microbial origin enzymes/cheese rennets on milk clotting and cheese ripening stages are discussed.

Key Words:Chymosin, Rennin, Rennet varieties, Milk-clotting enzyme, Cheese.

The presence of microorganisms, which we share our bodies, has been known for years. The human body is a structure that hosts both its own genome and genome belonging to a group of microbes that live together. However, changes in our lifestyle and new molecular compounds we encounter cause various effects on microorganisms. Recent studies also indicate that these groups of microorganisms have more serious impact on human health than expected. Enlightening this structure and interaction between them will obviously make important contributions on microbiome’s impact on human health and even in determining the treatment of diseases.

Key Words: Microbiome, Nutrition, Health.

Aroma, which has a great influence on consumer preferences and economic value, has an important place in the food industry. These volatile and sensitive valuable components can be encapsulated with shells or matrices of coating materials such as monomers or polymers. The encapsulation of aroma components, which are usually liquid at room temperatures, can provide advantages such as protection from environmental factors and increased shelf life when the product is in a powder form. Techniques such as spray drying, spray cooling, extrusion, freeze drying, coacervation and molecular inclusion are used in the encapsulation of aroma components. In this study, studies on the encapsulation of aroma components with various technologies used in the food industry are reviewed.

Key Words:Microencapsulation, Aroma retention, Microencapsulation techniques, Powdered particles, Coating materials.

Pesticides commonly used worldwide are chemicals used as agricultural, industrial, domestic and war materials. Although pesticides are very strongly associated with many health problems, there is a serious lack of monitoring and identification of these pollutants. Conventional chromatographic methods such as high performance liquid chromatography, capillary electrophoresis and mass spectrometry are effective methods for pesticide analysis in foods. However, these methods have considerable limitations in terms of complex processes, time-consuming preparatory steps, expensive equipment and expert staff requirements. Biosensors are preferred devices for the determination of pesticides because of their simplicity, high sensitivity, short analysis time and low analysis cost, as well as their applicability to real time measurements. For more than fifteen years, biosensors based on enzyme inhibition have been developed to monitor pesticide residues for food control and safety. Conductive polymers have been used during constructions of these pesticide biosensors. In this study, studies on biosensors used for pesticide analyses were summarized and then researches on acetylcholinesterase inhibition based biosensors developed by using conducting polymers for pesticide analyses were reviewed.

Key Words: Pesticide, Conducting polymer, Biosensor, Enzyme, Food, Water.

Turkey, especially Southeastern Anatolian Region, has an important place in the world ranking as well as an economic value in terms of pistachio production. Pistachios, which are from nuts with hard shells, have positive effects on health. Pistachios have rich nutritional content in terms of protein, fat and fatty acids, fiber, vitamins and minerals. As a rich source of phenolic compounds, pistachios take attention with a high antioxidant activity. Various researchers have reported that pistachio consumption may have beneficial effects on hypertension, cancer, diabetes and cardiovascular diseases. In this present study, the place and the importance of pistachios in human nutrition and health are reviewed.

Key Words: Pistachio, Health, Phenolic compounds, Antioxidant activity, Nutrition.