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University of Technology of Compiègne, France

Oniszczuk T.,University Przyrodniczy w Lublinie | Pilawka R.,West Pomeranian University of Technology
Przemysl Chemiczny | Year: 2013

Com. starch was compounded with cellulose fibers (up to 30% by mass), plasticized with glycerol (20% by mass), granulated by extrusion at 80-120°C and screw speed 60-100 rpm, and finally studied for thermal decompn. by thermogravimetry in air (up to 1173 K). Three-stage decomposition was obsd. During the 1ststage (up to 473 K), only weak chem. bonds were destroyed. During the 2nd stage (up to 673K), the composite material was oxidized mainly to CO2 During the 3rd stage, combustion of C took place. Decompn. rate consts., reaction orders, activation energies and pre-exponential factors were calcd. from the exptl. data. The addn. of fibers resulted in a decrease in thermal resistance of the composite material. Source

The washed Brussels sprouts heads were coated through dipping in a coat, i.e. in an aqueous solution of pea protein (10 % w/w), candelilla wax (2 % w/w), and sorbitol (4 % w/w). The coated and uncoated (control) vegetables were stored in the simulated storage conditions (~20 °C in a relative humidity of 50 %) for 10 days. The quality assessment of Brussels sprouts comprised the determination of: mass loss, contents of ascorbic acid, polyphenols and chlorophyll, polyphenol oxidase activity (PPO), colour, texture, and sensory properties. It was evidenced that the coating of Brussels sprouts by protein-wax coating resulted in a significant reduction in mass loss, vitamin C, polyphenols, and firmness during storage, as well as limited the softening of the vegetables. However, the presence of the coating had no effect on the PPO activity and on the content of chlorophyll pigments. The colour measurements proved that during the final stage of storing, the coated vegetables were significantly lighter and more yellow compared with the control samples. A sensory analysis performed on the 4 th day of storage showed that the coating of Brussels sprouts favourably impacted their overall appearance, firmness, and gloss, but slightly deteriorated their odour. After 4 days of storage, the sensory quality of Brussels sprouts, both in coated and uncoated samples, decreased below the acceptable level. The results obtained prove that the coating using the emulsion suggested can impact the course of some physiologic and biochemical processes in the Brussels sprouts, which affect their commercial and consumption quality. Source

This paper presents the theoretical basis for the conception of environmental competitiveness of regions. It was pointed out, that the less developed regions are in a possession of a very precious commodity, i.e. their natural environment. There are wide possibilities to use their natural environment as a trading mark and in this way to spur their economic development. This could both stimulate the economic prosperity of the regions and contribute to enhancing the quality and quantity of their natural environment; in order to sell a product one has to be sure that it is of the best quality. Taking better care of the natural environment would further contribute to deepening the regions' green specialization and enhancing their level of competitiveness on the national or even international scale. In fact, it is capable to use a new term for this idea - environmental competitiveness of regions. Source

The objective of this study was to produce processed cheese analogues, in which acid casein was partially replaced by different whey preparations ('DWP 50' demineralised whey powder, 'WPC 35' whey protein concentrate), as well as to assess the adhesiveness of the above mentioned analogues to different packaging materials: stainless steel (SS), aluminum (AL), polymethyl methacrylate (PMMA), polyamide (PA), polyvinyl chloride (PVC), and polytetrafluoroethylene (PTFE)). The adhesiveness of processed cheese analogues was measured using a TA-XT2i Texture Analyser. The adhesiveness of all the processed cheese analogues studied increased along with the increase in the content of protein level in the product. The addition of demineralised whey powder (DWP 50) caused the adhesiveness of processed cheese analogues to significantly increase compared to the products produced with the addition of whey protein concentrate (WPC 35) and to the model analogues made from acid casein only. The cheese analogues showed the lowest adhesiveness to the packaging materials made of aluminium (AL) (the samples with WPC 35 added and the samples made of acid casein only) and to the polytetrafluoroethylene (PTFE) packagings (the samples produced with the whey preparations added). As regards the packagings made of polyvinyl chloride (PVC), all the cheese samples produced with the addition of 2 % of the protein preparations showed the highest adhesiveness to this material. The cheese analogues with the demineralised whey powder (DWP 50) added were the most adhesive to all the packaging materials tested. Source

In the paper as presented, the effect was determined of the polarity of sorbents in solid phase extraction on the contents of phenylpropanoids in extracts obtained from a pepper pericarp. Three types of sorbents were analyzed: silica gel modified with octadecyl (C18), ethylophenyl (Phe), and cyanopropyl (CN), and, in every case, the same system of solvents was applied. The extraction yield was determined using three derivatives of quercetin as the standards; those derivatives were isolated from the pepper pericarp during the preceding studies. The standards comprised: quercetin 3-O-rhamnoside-7-O-glucoside, quercetin-3-O-glucoside, and quercetin-3-O-rhamnoside. Next, the fractions of phenolic compounds were isolated from the pepper pericarp with the use of the three above indicated sorbents. In the fractions obtained, the content of quercetin derivatives was quantitatively determined by a HPLC method and with the use of the standard curves for each compound. Additionally, there were determined the total of phenolic compounds by a Folin-Ciocalteu method and their antiradical activity in the system with DPPH radical. Of the three standards applied, the quercetin-3-O-glucoside was recognized for its highest extraction yield; it was characterized by an intermediate polarity. Among the sorbents analyzed, the most effective sorbent was the silica gel modified with cyanopropyl. Also in the case of the fraction of phenolic compounds present in the pepper fruits, the highest extraction efficiency was obtained for the same gel used. This fact was confirmed by the results of total phenolic compounds and antiradical activity. Source

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