Effects of pH on the Adsorption and Desorption of Naringin onto Zymosan A in Aqueous Systems

This study aimed to investigate the interactions between naringin and dietary fiber from yeast (zymosan A) through adsorption and desorption processes. The effects of different solution pH conditions (pH 3.0, pH 7.0, and pure water at pH 5.5), as well as varying initial concentrations of zymosan A and naringin, on their interaction were examined. The adsorption capacity of naringin onto zymosan A was higher at pH 7.0 (12 to 275 mg g–1), lower in water (6 to 83 mg g–1) and lowest at pH 3.0 (0 to 55 mg g–1). The desorption ratio was lowest in pH 3.0 solution, followed by water and pH 7.0 solution. UV-Vis and FTIR spectral analyses confirmed the binding of naringin onto zymosan A. The antiradical activity for naringin was highest at pH 3, followed by pH 7 and pure water. For the naringin-zymosan A complex, antiradical activity was highest at pH 3, with similar but lower values at pH 7 in pure water. This work is licensed under a Creative Commons Attribution 4.0 International License

Impact analysis of different chemical pre-treatments on colour of apple discs during drying process

The main purpose of this study was to compare colour changes of chemically pre-treated dried apple discs. Changes were observed by chromameter in L*a*b* colour model by using Minolta chromameter CR-400 and by image analysis system in RGB colour model. Apple discs variety "Gold Rush" were pre-treated and dried in laboratory tray drier at drying temperature 70 °C and at airflow velocity of 1.5 ms-1. Different chemical pre-treatments were applied on apple discs (dipping in 0.5% ascorbic acid solution; 0.3% L–cysteine solution; 0.1% 4–hexyl resorcinol solution and 1% sodium metabisulphite solution). Mean values of colour parameters, colour changes and correlation coefficients for apple discs were calculated for both colour models. The analysis showed statistically significant influence of pre-treatment method on total colour changes for both chosen colour models of dried apples. Calculated correlation coefficient between colour changes for used models was found to be 0.894. According to colour characteristics the best results were achieved when samples were pre-treated with 0.5% ascorbic acid solution. According to calculated results it was found that image analysis method as well as colorimetric method can be used to observe the colour changes on dried apple discs

Honey botanical origin determination by electronic nose

Four different honey types (Acacia, Robinia pseudoacacia; chestnut, Castanea sativa; lime, Tilia sp.; sage, Salvia officinalis) from Croatia were analysed using an electronic nose to capture the aroma profile. Principal Component Analysis (PCA) and Artificial Neural Network (ANN) models were used to determine the botanical origin of honey samples. Overall accurate classification was over 90% which suggests that an electronic nose could be used as fast screening method for the determination of honey botanical origin

Ružička Days : 13th Ružička Days International Scientific and Professional Conference "Today science-tomorrow industry" : proceedings

Zbornik sadrži sažetke radova prezentiranih na Skupu u vidu 7 plenarnih predavanja, 15 usmenih i 102 posterska priopćenja podijeljena u sekcije: kemijska analiza i sinteza, kemijsko i biokemijsko inženjerstvo, prehrambena tehnologija i biotehnologija, medicinska biokemija i farmacija, kemija u poljoprivredi i šumarstvu, zaštita okoliša, uz prikaz sažetaka radova prezentiranih na susretu mladih kemičara u okviru Skupa.The proceedings contain summaries of papers presented at the Conference in the form of 7 plenary lectures, 15 oral and 102 poster presentations divided into sections: chemical analysis and synthesis, chemical and biochemical engineering, food technology and biotechnology, medical biochemistry and pharmacy, chemistry in agriculture and forestry, environmental protection, along with a presentation of summaries of papers presented at the meeting of young chemists within the Conference

Ružička Days : 13th Ružička Days International Scientific and Professional Conference "Today science-tomorrow industry" : book of abstracts

Zbornik sadrži sažetke radova prezentiranih na Skupu u vidu 7 plenarnih predavanja, 15 usmenih i 102 posterska priopćenja podijeljena u sekcije: kemijska analiza i sinteza, kemijsko i biokemijsko inženjerstvo, prehrambena tehnologija i biotehnologija, medicinska biokemija i farmacija, kemija u poljoprivredi i šumarstvu, zaštita okoliša, uz prikaz sažetaka radova prezentiranih na susretu mladih kemičara u okviru Skupa.The proceedings contain summaries of papers presented at the Conference in the form of 7 plenary lectures, 15 oral and 102 poster presentations divided into sections: chemical analysis and synthesis, chemical and biochemical engineering, food technology and biotechnology, medical biochemistry and pharmacy, chemistry in agriculture and forestry, environmental protection, along with a presentation of summaries of papers presented at the meeting of young chemists within the Conference