Development and characterization of black mulberry (Morus nigra) pekmez (molasses) composite films based on alginate and pectin.

Production of composite films is an important approach to improve functionality of edible films, by combining different polysaccharides, proteins, and lipids. Carbohydrate-based composite films are most attractive, which have good film-forming ability due to their unique colloidal properties. Fruit purees include high polysaccharide content that plays a role to have desirable film properties including mechanical resistance, efficient barrier properties, and selective permeability against oxygen transmission. The purpose of this study was to characterize physical, barrier, mechanical, thermal, and water sorption properties of composite films formulated with different mulberry pekmez concentrations (26, 32, and 38 °Brix) based on alginate or pectin. All film-forming solutions were showed shear thinning behavior with higher yield stress and viscosity-shear rate data were fitted to Ostwald de Waele model (R2 ≥ 0.943). A noticeable decrease in tensile strength of films with increasing concentration was determined, but films prepared with high concentration showed more flexible. The mechanical properties of pectin films exhibited weakened properties compared to alginate films. Increasing pekmez concentration in the film matrix improved the water vapor permeability of alginate films, whereas pectin films showed reverse behavior as resulting in cracks and crack propagation within the structure. The sorption isotherms of films showed a typical profile of foods contain high soluble components and the Guggenheim-Anderson-deBoer (GAB) model gave a good fit for all of the obtained data. The results showed that mulberry pekmez films based alginate have a potential for food applications depends on the physical properties and for the replacement of non-biodegradable plastic packaging.

Influence of an ultrasonic nozzle in spray-drying and storage on the properties of blueberry powder and microcapsules.

BACKGROUND: Recently, ultrasonic nozzle technology has been applied in spray-drying because of its numerous advantages, including providing more uniform droplets and reducing damage observed in bioactive compounds. In this study, the production of blueberry powders and microcapsules by using an ultrasonic spray nozzle was investigated. Firstly, the important ultrasonic nozzle parameters were optimised by using response surface methodology and compared with a conventional nozzle (control). Secondly, powder and microcapsules obtained at the optimum point were stored at 22 °C and 35 °C at 0.32 water activity (aw ). RESULTS: The optimum conditions were estimated as 125 °C inlet air temperature, 9 W ultrasonic power and 8% feed pump rate. There was significantly difference (P < 0.05) in the total phenolic content and antioxidant power of microcapsules produced by an ultrasonic nozzle and a conventional nozzle. Because the temperature affected the stability of powders negatively, the blueberry powder showed higher losses than microcapsules in the content of bioactive compounds. In addition, the ultrasonic nozzle showed a significantly greater protective effect on physico-chemical properties than did the conventional nozzle. CONCLUSION: Results of the study point that the production of ultrasonic nozzle powders and microcapsules is feasible to use as a functional ingredient in food industry. © 2016 Society of Chemical Industry.

Microbial communities involved in Kasar cheese ripening.

The microbiota of non-starter lactic acid bacteria (NSLAB) and their concomitant community dynamics during cheese ripening were investigated for traditional Turkish Kasar cheeses made from raw cows' milk. Five batches of 15 Kasar cheeses produced in different dairy plants located in Kars were analysed during their whole ripening phase up to 180 days. Lactobacilli and lactococci were determined as the prevailing microbial groups. The molecular classification and identification of 594 LAB isolates during Kasar cheese ripening were performed through (GTG)5-PCR fingerprinting of their genomic DNA followed by verification of the (GTG)5-PCR clusters obtained after numerical analysis through 16S rRNA gene sequencing of representative isolates. Lactobacillus casei (247 isolates, 41.6%), Lactobacillus plantarum (77 isolates, 13.0%), and Pediococcus acidilactici (58 isolates, 9.8%) were the prevailing NSLAB species in all Kasar cheeses of the different dairy plants investigated throughout cheese ripening. The data of the present study contribute to the inventory of unique cheese varieties to enable the prevention of losses of microbial biodiversity and the selection of starter cultures for controlled cheese manufacturing.

Natamycin content and quality evaluation of yoghurt from small- and large-scale brands in Turkey.

In this study, the presence of natamycin and quality parameters of yoghurt samples manufactured by small- and large-scale dairy firms in Turkey were investigated. Physicochemical and microbiological results revealed that, except Lactobacillus bulgaricus and Streptococcus thermophilus counts, the majority of the yoghurts manufactured by small-scale dairy firms were found to be out of the limits. Natamycin was detected in 31 and 2 yoghurt samples from small- and large-scale brands, respectively. The levels of natamycin in small-scale brand yoghurts were higher than those in large-scale brand yoghurts. Of the analysed samples, 42.3% did not comply with the Turkish Food Codex.

Toxic and essential elements in butter from the Black Sea region, Turkey.

In this study, 88 randomly selected samples of butter produced in the Black Sea region of Turkey were purchased from different retail markets during different periods and investigated for toxic and essential elements content. Quantitative analyses of elements in the samples were performed using an inductively coupled plasma-mass spectroscopy (ICP-MS). Mean concentrations of As, Cr, Cu, Fe, Mn, Ni, Pb, Se and Zn in the butter samples were 18.93, 100.32, 384.66, 4199.1, 887.47, 168.64, 56.13, 16.34 and 384.66 µg kg(-1), respectively. Cd and Co were detected in 19 (mean content 0.29 µg kg(-1)) and 81 (mean content 3.81 µg kg(-1)) samples of 88 butter samples, respectively. However, the dietary intake of these elements by the population of the Black Sea region is currently well below the dietary reference intake (DRI) and provisional tolerable weekly intake (PTWI) levels of essential and toxic elements.