Effect of high pressure on selected properties and shelf-life of poultry burgers

Celem badań było określenie wpływu wysokiego ciśnienia (500 MPa, 10 min, 10 ºC) na wybrane właściwości oraz trwałość kotlecików z mięsa drobiowego. Po 24 h od zastosowania wysokiego ciśnienia oraz po 2 i 3 tygodniach przechowywania zapakowanych próżniowo kotlecików w temp. 4 - 6 ºC wykonano badania fizyczne, chemiczne i mikrobiologiczne. Stwierdzono, że dzięki zastosowaniu wysokiego ciśnienia można uzyskać wyższą jakość mikrobiologiczną, a tym samym trwałość zapakowanych próżniowo kotlecików. Po 3 tygodniach przechowywania w temp. 4 - 6 ºC, liczba drobnoustrojów mezofilnych, psychrotrofowych i bakterii kwasu mlekowego w kotlecikach poddawanych działaniu wysokiego ciśnienia była o 5 - 6 cykli logarytmicznych mniejsza niż w wyrobach kontrolnych. Jednocześnie zastosowanie wysokiego ciśnienia nie wpłynęło w istotny sposób na ilość wycieku przechowalniczego, teksturę, barwę oraz tempo utleniania lipidów w kotlecikach drobiowych.The objective of this study was to determine the effect of high pressure treatment (500 MPa, 10 min, 10 ºC) on the selected properties and shelf-life of poultry burgers. 24 hrs after the application of high pressure, and 2 and 3 weeks after storing the vacuum-packed patties burgers at a temparture of 4 - 6 ºC, the physical, chemical, and microbial analyses were performed. It was found that, owing to the high pressure applied, it was possible to achieve a better micro-biological quality, thereby a long lasting shelf-life of the burgers. 3 weeks after storing the high pressure-treated burgers at 4 - 6 ºC, the counts of mesophilic, psychrotrophic, and lactic acid bacteria in them were lower by 5 - 6 logs compared to the control products. At the same time, the application of high pressure did not significantly affect the level of drip loss during storage, nor the colour, texture, and lipid oxidation rate in the poultry patties (burgers)

Real-Time Raman monitoring and control of the catalytic acetalization of glycerol with acetone over modified mesoporous cellular foams

The acetalization of glycerol with acetone over modified mesoporous cellular foam materials has been widely investigated using in situ Raman spectroscopy during reaction. Mesoporous cellular foams (MCFs) modified by niobium or tantalum and (3-mercaptopropyl)trimethoxysilane (MP) followed by H2O2 treatment were used as catalysts in the acetalization of glycerol with acetone. The influence of the type of catalyst, which determines the solid texture and number of Brønsted acid sites, and different reaction parameters, such as reaction time, reaction temperature, glycerol/acetone ratio, and catalyst amount on acetalization reaction, were investigated. The results obtained in the characterization of the catalysts show that the materials obtained differ in the number of Brønsted acidic sites. Raman spectroscopy provides noninvasive insight during acetalization of glycerol with acetone in the presence of acid heterogeneous catalysts. The progress of the acetalization reaction was monitored following the variation in intensity of characteristic Raman bands and using chemometric analyses. The results obtained by real-time Raman monitoring confirm the mechanism proposed for the reaction, which proceeds via the formation of the 3-(2-hydroxypropan-2-yloxy)propane-1,2-diol intermediate, whose presence is confirmed by Raman spectroscopy. Under optimal reaction conditions, the 5-membered ring ketal 2,2-dimethyl-1,3-dioxolane-4-yl methanol (solketal) was obtained with the highest selectivity (99%). Raman monitoring enables real-time control of the reaction, thus enabling the optimization of reaction conditions for a more efficient reaction. Raman monitoring illustrates the reversibility of the reaction upon evaporation of acetone, even under reflux.The authors acknowledge funding from Spanish Ministry Project CTQ2011-13343-E. National Science Centre in Poland is acknowledged for financial support (Projects 2011/01/B/ ST5/00847, 2011/03/N/ST5/04772, and 2013/08/T/ST5/ 00010). K.S. thanks the Adam Mickiewicz Foundation in Poznan for scholarship in 2013.Peer Reviewe

Acetalization of glycerol with acetone over mesoporous cellular foams (MCF) modified with niobium and tantalum

Trabajo presentado en el 8th International Symposium on Group Five Compounds, celebrado en Málaga (España) del 24 al 27 de junio de 2014.Peer Reviewe

Real-time raman monitoring the one pot synhesis of mcf materials modified with metals and (3-mercaptopropyl) trimethoxysilane

Trabajo presentado en el Characterization of Molecular Sieves, celebrado en Praga (República Checa) del 10 al 12 de marzo de 2013.Peer Reviewe

Mesostructured cellular foams modified by niobium or tantalum and functionalized with (3-mercaptopropyl)trimethoxysilane - Raman inspired reduction of synthesis time

The synthesis of mesostructured cellular foams (MCF) modified by niobium or tantalum source and functionalized with MPTMS (3-mercaptopropyl)trimethoxysilane was monitored in situ by Raman spectroscopy. The results from Raman monitoring prompted us to check for a possibility of shorter time synthesis of mesostructured cellular foams. A series of MCFs materials prepared using different times of gel mixing (5 h and standard 20 h) were synthesized. The samples obtained were characterized by N2 adsorption/desorption, XRD, TEM, XRF, elemental analysis, UV–Vis, FTIR and amperometric titration. The effects of niobium and tantalum on the rate and efficiency of thiol oxidation as well as on the time of silica formation were explored. The most important outcome of the study is the evidence of the formation of MCFs materials having strong Brønsted acidic centers in a shorter preparation time. SO3H groups form faster than in MP-MCF material in the presence of niobium or tantalum in the synthesis gel. The extension of synthesis time for silica and tantalosilicate samples leads to more efficient oxidation of thiol species. This feature does not depend on the synthesis time of niobiosilicate materials.National Science Centre in Poland (projects no. 2011/03/N/ST5/04772 and 2013/08/T/ST5/00010) is acknowledged for a financial support and Adam Mickiewicz Foundation in Poznan for K. Stawicka scholarship in 2013. The authors also acknowledge the Spanish Ministry (grant CTQ2011-25517).Peer Reviewe

Incorporation of group five elements into the faujasite structure

Niobium and tantalum were incorporated into the faujasite aluminosilicate structure in one-pot synthesis and also by post-synthesis method, i.e. solid-state ion exchange. One-pot synthesized zeolites exhibit Nb and Ta incorporated into the zeolite skeleton as evidenced by different methods. The efficiency of metal incorporation examined by XPS measurements was found to be higher for tantalum than for niobium