Physicochemical properties of low‐fat soft cheese Turkish Beyaz made with bacterial cellulose as fat mimetic

The effects of incorporating various concentrations of bacterial cellulose (BC) (1.7 and 3.5% w/v) on the physicochemical and sensorial properties of low‐fat soft cheese Turkish Beyaz were investigated during a 60‐day ripening period. Control cheeses were produced using nonfat, half‐fat (1.7% fat) and full‐fat milk, for comparison. Depending on changing fat percentage, some physicochemical properties of cheeses, such as moisture, pH and salt showed significant differences, but BC had no influence on these properties. Fat content and BC altered the textural and sensory properties. These results indicated that BC improved the quality of reduced‐fat and low‐fat Turkish Beyaz cheeses.     

QUALITY CHARACTERISTICS OF CORN NOODLES CONTAINING GELATINIZED STARCH, TRANSGLUTAMINASE AND GUM

ABSTRACT

Effects of gelatinized corn flour addition level (40, 60 and 80%), gum (locust bean gum or xanthan gum, 3%) and/or transglutaminase (TG, 0.5%) on quality characteristics of corn noodle were investigated. Gelatinized corn flour was used as a binder for remaining untreated corn flour (60, 40 and 20%). Corn noodles were evaluated in terms of cooking properties (cooking loss, total organic matter (TOM), water absorption, swelling volume and maximum force), color, sensory and pasting properties. Noodle sample containing gelatinized corn flour at level of 80% exhibited best cooking and sensory properties. Gum and/or TG were added to this noodle formula. Gum improved noodle quality in terms of some cooking properties. Improving effect of xanthan gum was more obvious. Covalent crosslinks catalyzed by TG caused significantly lower cooking loss and TOM values. Gums generally caused increases in Rapid ViscoAnalyzer viscosity values of noodles. Gum and/or TG show great promise in processing of gluten‐free corn noodle.

PRACTICAL APPLICATIONS

Celiac disease occurs in about one in 300 people in Europe. Lack of gluten in cereals that are safe for gluten‐free food causes major problems in dough processing and product quality. Technological difficulties in production and lack of awareness of number of celiac patients in need of gluten‐free products might restrict researches related to gluten‐free food. In recent years, various approaches to overcome the technological problems are arising. Searching for ingredients that have ability to mimic properties of gluten in production of gluten‐free food is the most common approach. We report herein beneficial effects of gelatinization, gum (locust bean gum, xanthan gum) and/or transglutaminase (TG) in gluten‐free corn noodle production. They have major improving effects in noodle quality and show great promise as a processing aid in bulk manufacture of gluten‐free corn noodle. To the best of our knowledge, there is no study investigating utilization of TG in gluten‐free corn noodles.     

Nanoindentation study on Gd-deposited YBaCuO superconductor

Nanoindentation technique was used to characterize the mechanical properties of Gd-deposited bulk YBaCuO superconductors fabricated by solid-state reaction method. In order to determine the hardness and reduced modulus of the samples, load-displacement data were analysed by using the Oliver–Pharr method. The hardness values exhibited significant peak load-dependence especially at lower peak loads, while the reduced modulus values were found to be nearly constant at studied loading range. In order to find true hardness of the samples, the peak load-dependency of hardness was analysed by using Meyer’s law, minimum resistance model, elastic/plastic deformation model, energy balance model, Nix–Gao model and Mukhopadhyay approach. Of the aforementioned models, energy balance model and Mukhopadhyay approach were found to be the most effective models to explain the load-dependency of hardness.     

An investigation of some properties of banana yogurts made with commercial ABT-2 starter culture during storage

Five yogurt batches were prepared with banana puree and sugar combinations and ABT-2 ( Streptococcus salivarius ssp. thermophilus, Lactobaccilus acidophilus and Bifidobacterium spp.) as starter culture. The addition of fruit influenced ( P <  0.05) the syneresis, titratable acidity and pH, whereas the viscosity value, and S. salivarius ssp. thermophilus, L. acidophilus and Bifidobacterium spp. counts were found to be insignificant. Storage time significantly ( P <  0.05) affected the syneresis, titratable acidity, pH value, and S. salivarius ssp. thermophilus counts, while the viscosity value and L. acidophilus and Bifidobacterium spp. counts were not affected. The sensory evaluations showed that the sample B was most preferred by panellists.     

Heavy metal concentrations in raw milk collected from different regions of Samsun,Turkey

In this study, 144 raw milk samples were analysed for heavy metal contamination derived from emissions from industrial operations in Tekkekoy, Samsun, Turkey. Cu, Fe, Zn, Cr, Ni, Cd, As and Pb levels in samples were determined by inductively coupled plasma mass spectrometry (ICP‐MS). The average amounts of copper, chromium, iron, zinc, nickel, cadmium, arsenic and lead were determined as 1.130, 0.441, 12.920, 0.032, 0.483, 0.006, 0.003 and 0.004 mg/kg, respectively. It was determined that the summer period has the highest levels for copper, lead and cadmium. The highest contents of arsenic and copper were found at the two industrial regions that were close to Black Sea, described as ‘1st’ and ‘2nd’ region. Whereas the 3rd and 4th regions that were far from an industrial zone and also from the Black Sea, nickel, lead and chromium had the highest levels.     

Utilization of Transglutaminase to Increase the Level of Barley and Soy Flour Incorporation in Wheat Flour Breads

ABSTRACT: This study investigated the possibility of incorporating barley or soy flour into wheat flour using transglutaminase (TG)-catalyzed cross-linking, without deterioration in bread quality. A Farinograph and texture analyzer were used to examine mixing properties and extensibility of doughs, respectively. Addition of increasing levels of barley/soy flour (with and without TG) increased Farinograph water absorption in the soft and hard wheat cultivars studied. Dough resistance increased and extensibility decreased with TG treatment. TG showed great promise in processing of bread supplemented with barley flour, even at a very low level (0.25%, wt/ wt), but did not notably improve the quality of soy flour-supplemented breads.