Mineral substances in honey

Cilj ovog istraživanja bio je određivanje kalcija i magnezija prisutnih u bagremovom i cvjetnom medu prikupljenom od hrvatskih pčelara. Istraživanje je provedeno na deset uzoraka bagremovog i deset uzoraka cvjetnog meda. Uzorci su tretirani tehnikom „suhog“ spaljivanja, nakon čega su podvrgnuti mineralizaciji u mufolnoj peći. Udio kalcija i magnezija određen je na atomskom spektrofotometru Perkin-ELMER 2380. Dobiveni rezultati ukazuju na značajno veću količinu prisutnih mineralnih elemenata u cvjetnom medu, u usporedbi sa bagremovim. Takvi rezultati su u korelaciji s podacima iz literature, koji navode da tamniji medovi imaju veću koncentraciju minerala od svijetlih medova. Izmjerene koncentracije kalcija i magnezija bile su približne drugim provedenim istraživanjima na području Hrvatske.The goal of this research was to determine calcium and magnesium content of black locust and medow honey collected from Croatian beekeepers. Research was done on ten samples of black locust honey and ten samples of medow honey. Samples were treated with „dry“ burning method after which they were subjected to mineralization in muffle furnace. Calcium and magnesium was determined with atomic absorption spectrometer Perkin-ELMER 2380. Obtained results indicate that there is a larger amount of mineral elements in medow honey in comparison to black locust honey. This results are in correlation with results in literature from which we can conclude that dark honeys have a higher mineral content than pale ones. Measured concentration of calcium and magnesium were close to those measured in other research in Croatia

Influence of non-thermal processing techniques on sulfur dioxide and oxygen concentrations in young and aged wines

The application of innovative techniques like high hydrostatic pressure (HHP) and high power ultrasound (HPU) for food processing and preservation is one of the current topics in food science. In the enological field, these techniques have been identified as alternative methods for wine microbial stabilization and acceleration of wine aging process. Due to lack of available information about their influence on physicochemical characteristics, the aim of this work was to study the effect of HHP and HPU on sulfur dioxide and dissolved oxygen concentrations in red and white wines. The effect was evaluated immediately after the treatment and after 3, 6 and 12 months of aging in bottles. Moreover, the synergistic effect of mentioned techniques along with antioxidants additions (glutathione and SO2) was also evaluated. The results showed that the concentrations of free and total SO2 did not change immediately after HHP treatments, while after HPU processing there was no clear trend in analyzed parameters. As expected, results showed that both, free and total SO2 decreased during storage period of red and white wines. Regarding both applied techniques, slightly higher concentrations of free SO2 were observed in samples treated by HHP after 12 months of storage. Oxygen concentration slightly increased immediately after the treatments, with the highest concentration determined after HPU processing. During aging, its concentrations decreased and were similar or slightly higher than of those determined in untreated samples. Regarding the antioxidants additions, better protective effect was obtained by addition of higher concentration of SO2 than glutathione, since these samples were characterized by lower concentrations of dissolved oxygen

Impact of high hydrostatic pressure on composition of polyphenols and chromatic characteristics of wine Cabernet Sauvignon

Visoki hidrostatski tlak netoplinska je metoda obrade hrane, a potencijal ove tehnologije kao enološke prakse je nedovoljno istražen. Cilj ovog rada bio je ispitati utjecaj visokog hidrostatskog tlaka od 200, 400 i 600 MPa u trajanju od 5, 15 i 25 minuta na sastav polifenola i kromatske karakteristike vina Cabernet Sauvignon. Koncentracija ukupnih fenola, tanina, antocijana i kromatske karakteristike (svjetlina, akromatske osi a i b, kromatičnost i kut tona boje) određene su primjenom spektrofotometrijskih metoda. Koncentracija slobodnih antocijana određena je primjenom tekućinske kromatografije visoke djelotvornosti (HPLC). Dobiveni rezultati pokazali su kako je utjecaj tretmana visokim hidrostatskim tlakom ovisio o primijenjenom tlaku te duljini tretiranja. Primjena tretmana od 200 MPa tijekom 5 minuta nije rezultirala značajnijim promjenama u sastavu polifenola i kormatskih karakteristika. S druge strane, primjena viših tlakova kroz dulje vrijeme, a posebice 600 MPa tijekom 15 i 25 minuta uzrokovala je značajan pad koncentracije ukupnih fenola, ukupnih i slobodnih antocijana, kao i porast kromatskih parametara.High hydrostatic pressure is a non-thermal food processing method. However, potential of this technology as enological practice has not been profoundly studied. The aim of this study was to investigate the influence of high hydrostatic pressure of 200, 400 and 600 MPa after treatment of 5, 15 and 25 minutes on the polyphenolic and the chromatic characteristics of wine Cabernet Sauvignon. Analysis of total phenols, tannins, anthocyanins and chromatic characteristics (lightness, a value, b value, chroma, hue angle) was performed using spectrophotometric methods. Analysis of free anthocyanins was conducted by high performance liquid chromatography (HPLC). The results obtained showed that the effect of high hydrostatic treatment was depended on the applied pressure and treatment duration. The application of 200 MPa treatment for 5 minutes did not result in significant changes of polyphenolic and chromatic characteristics. Application of higher pressures over a long period of time, and in particular 600 MPa, during 15 and 25 minutes, caused a significant decrease in the concentration of total phenols, total and free anthocyanins, as well as the increase of chromatic parameters

Mineral substances in honey

Cilj ovog istraživanja bio je određivanje kalcija i magnezija prisutnih u bagremovom i cvjetnom medu prikupljenom od hrvatskih pčelara. Istraživanje je provedeno na deset uzoraka bagremovog i deset uzoraka cvjetnog meda. Uzorci su tretirani tehnikom „suhog“ spaljivanja, nakon čega su podvrgnuti mineralizaciji u mufolnoj peći. Udio kalcija i magnezija određen je na atomskom spektrofotometru Perkin-ELMER 2380. Dobiveni rezultati ukazuju na značajno veću količinu prisutnih mineralnih elemenata u cvjetnom medu, u usporedbi sa bagremovim. Takvi rezultati su u korelaciji s podacima iz literature, koji navode da tamniji medovi imaju veću koncentraciju minerala od svijetlih medova. Izmjerene koncentracije kalcija i magnezija bile su približne drugim provedenim istraživanjima na području Hrvatske.The goal of this research was to determine calcium and magnesium content of black locust and medow honey collected from Croatian beekeepers. Research was done on ten samples of black locust honey and ten samples of medow honey. Samples were treated with „dry“ burning method after which they were subjected to mineralization in muffle furnace. Calcium and magnesium was determined with atomic absorption spectrometer Perkin-ELMER 2380. Obtained results indicate that there is a larger amount of mineral elements in medow honey in comparison to black locust honey. This results are in correlation with results in literature from which we can conclude that dark honeys have a higher mineral content than pale ones. Measured concentration of calcium and magnesium were close to those measured in other research in Croatia

Impact of high hydrostatic pressure on composition of polyphenols and chromatic characteristics of wine Cabernet Sauvignon

Visoki hidrostatski tlak netoplinska je metoda obrade hrane, a potencijal ove tehnologije kao enološke prakse je nedovoljno istražen. Cilj ovog rada bio je ispitati utjecaj visokog hidrostatskog tlaka od 200, 400 i 600 MPa u trajanju od 5, 15 i 25 minuta na sastav polifenola i kromatske karakteristike vina Cabernet Sauvignon. Koncentracija ukupnih fenola, tanina, antocijana i kromatske karakteristike (svjetlina, akromatske osi a i b, kromatičnost i kut tona boje) određene su primjenom spektrofotometrijskih metoda. Koncentracija slobodnih antocijana određena je primjenom tekućinske kromatografije visoke djelotvornosti (HPLC). Dobiveni rezultati pokazali su kako je utjecaj tretmana visokim hidrostatskim tlakom ovisio o primijenjenom tlaku te duljini tretiranja. Primjena tretmana od 200 MPa tijekom 5 minuta nije rezultirala značajnijim promjenama u sastavu polifenola i kormatskih karakteristika. S druge strane, primjena viših tlakova kroz dulje vrijeme, a posebice 600 MPa tijekom 15 i 25 minuta uzrokovala je značajan pad koncentracije ukupnih fenola, ukupnih i slobodnih antocijana, kao i porast kromatskih parametara.High hydrostatic pressure is a non-thermal food processing method. However, potential of this technology as enological practice has not been profoundly studied. The aim of this study was to investigate the influence of high hydrostatic pressure of 200, 400 and 600 MPa after treatment of 5, 15 and 25 minutes on the polyphenolic and the chromatic characteristics of wine Cabernet Sauvignon. Analysis of total phenols, tannins, anthocyanins and chromatic characteristics (lightness, a value, b value, chroma, hue angle) was performed using spectrophotometric methods. Analysis of free anthocyanins was conducted by high performance liquid chromatography (HPLC). The results obtained showed that the effect of high hydrostatic treatment was depended on the applied pressure and treatment duration. The application of 200 MPa treatment for 5 minutes did not result in significant changes of polyphenolic and chromatic characteristics. Application of higher pressures over a long period of time, and in particular 600 MPa, during 15 and 25 minutes, caused a significant decrease in the concentration of total phenols, total and free anthocyanins, as well as the increase of chromatic parameters