Novel adhesive system based on 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) and hyperbranched polyglycerols

Two hyperbranched polyglycerols bearing 1,1,1-tris(hydroxymethyl)propane or Bisphenol A core and terminal hydroxyl functionality were examined as components of novel wood adhesive systems. Two 1,3-dimethylol-4,5-dihydroxyethyleneurea resins (DMDHEU) were used as crosslinkers. Shear strength tests revealed that the adhesives containing up to 75 wt% of renewable glycerol-derived polyglycerols retained performance comparable to that of neat DMDHEU. The results give way to extending the area of application of hyperbranched polyglycerols in the field of wood adhesives.     

An Improved Silver Ion HPLC Combined with Capillary Gas Chromatography of cis/trans Fatty Acids in Alimentary Fats and Human Milk Fat

A technique of analysis is described using a silver ion-loaded HPLC (Ag⁺/HPLC) column, gradient elution, and a laser light scattering detector followed by capillary gas chromatography (GC) for the determination of the fatty acid methyl ester (FAME) composition of rapeseed oil, the respective hydrogenated fat, some dietary fats, and human milk fat. With the use of Ag⁺/HPLC, FAMEs were separated into the following classes: saturated, trans-monounsaturated, cis-monounsaturated, trans–trans-di-unsaturated, trans–cis-di-unsaturated, cis–cis-di-unsaturated, and higher unsaturated FAMEs. Within each class, partial separation of positional isomers was also possible. Fractions of the eluate containing trans and cis C18:1 were separately collected and re-analyzed by GC in order to quantitate the positional isomers eight trans and nine cis in rapeseed oil and in human milk fat. The profiles of eight trans positional isomers in human milk fat and in hydrogenated rapeseed oil were alike but entirely different from that of six C18:1 trans isomers in bovine milk fat. Out of nine C18:1 cis isomers found in hydrogenated fat, only C18:1-9c and C18:1-11c were found in both human and bovine milk fat which may indicate some discrimination which occurs for certain isomers in fatty acid metabolism.     

Evaluation of performance of dough and bread incorporating chia (Salvia hispanica L.)

As a result of the opinion given by the European Food Safety Authority about the safety of chia seed (Salvia hispanica L) and whole ground chia seed as food ingredients, they may be placed on the market in the European Community as novel food ingredients to be used in bread products. The objective of the present investigation was to develop new cereal-based products with increased nutritional quality by using chia and ground chia seeds (whole chia flour, semi-defatted chia flour and low-fat chia flour) in order to evaluate its potential as a bread-making ingredient. The samples with chia addition significantly increased the levels of proteins, lipids, ash and dietary fibre in the final product compared to the control sample. Breads with seeds or ground seeds showed similar technological quality to the control bread, except for the increase in specific bread volume, decrease in crumb firmness and change in crumb colour. Sensory analysis showed that the inclusion of chia increased overall acceptability by consumers. The thermal properties of the starch did not alter substantially with the inclusion of chia. However, the incorporation of chia inhibited the kinetics of amylopectin retrogradation during storage, which would be directly related to the delay in bread staling.     

Strategies to improve the nutritional value of meat products: incorporation of bioactive compounds,reduction or elimination of harmful components and alternative technologies

Meat is an excellent source of protein with a good balance of amino acids. It is also rich in several minerals, vitamins and bioactive compounds, which play important roles in metabolism and are easily assimilated from meat compared with other foods. The nutritional value of meat is one of the factors that influence consumer acceptance. However, it can be significantly reduced during processing. Moreover, some operations, such as curing, smoking or fermentation, used for processing can lead to the formation of harmful components in meat, and hence, nutritionists associate high consumption of processed meat with an increased risk of several diseases such as cardiovascular disorders and cancers. This review deals with the distinctive aspects of the technological strategies that can be used to improve the nutritional value of meat products, including the incorporation of bioactive components, reduction or elimination of harmful components (e.g. nitrite/nitrate, fat) and alternative technologies (ultrasound).     

Colony-blot assay with anti-p60 antibodies as a method for quick identification of Listeria in food

The present study evaluated the ability to isolate Listeria from foods, using shortened procedure of sample enrichment followed by immunomagnetic separation or filtration methods, and serological identification of isolated bacteria by colony-blot and Western blot methods with anti-p60 antibodies. By these rapid methods, identification of Listeria was achieved in much shorter time (40-48 h) than with standard cultivation and biochemical identification procedures. The rapid methods used are easy to perform and, what is most important, their specificity is very high and fulfills the expectations. The possibility to select Listeria colonies growing on non-selective media by blotting with anti-p60 antiserum seems to be particularly valuable in examination of food samples containing/not too many Listeria (1-10 CFU/25 g). However, the blot method using anti-PepD mAb specific to unique region of L. monocytogenes p60 is necessary to distinguish L. monocytogenes from other Listeria species.     

Phytic acid concentration in selected raw materials and analysis of its hydrolysis rate with the use of microbial phytases during the mashing process

Phytic acid present in the raw materials can complex with many compounds and therefore limit their availability to the yeast during the alcoholic fermentation process. An effective utilization of biogenic compounds bound in phytates requires a detailed analysis of the raw materials for their phytic acid content. The aim of this study was to characterize the major technological parameters for selected raw materials used in the distilling industry (maize, rye, wheat and triticale grain) and to determine the phytic acid content and the IP6/total phosphorus ratio. The phytic acid hydrolysis rate during the mashing process, with the use of microbial phytases, was analysed. The highest phytic acid concentrations (2.30 ± 0.20 mg/g dry matter) and the highest IP6/total P (80.42 ± 6.99%) were observed in the maize grain samples. Therefore, further studies on the phytic acid hydrolysis rate with the use of various phytases were conducted for the maize grain. The highest hydrolytic activity was observed for the Phytase 10000L preparation. This was the preparation that hydrolysed the phytic acid completely in up to 90 min. The application of a highly effective phytase, in ethanol production from maize grain, could lead to a more effective utilization of the biogenic compounds during the fermentation process. Copyright © 2015 The Institute of Brewing & Distilling