Correlation of sensory and physicochemical properties of selected apple cultivars

Sensory and physicochemical changes of three apple cultivars (‘Golden Delicious’, ‘Idared’ and ‘Gloster’) were monitored during 14 weeks of storage at 6 °C and 70% relative humidity in three following years. The aim was to investigate physicochemical parameters that were best correlated with sensory evaluation of apples during their storage. Sensory quality was assessed using a category point scale and the sensory profile was evaluated using a graphical unstructured scale. Physicochemical changes, such as weight, soluble solids, titratable acidity, and dry matter content, were monitored. All the examined parameters changed during the observed period, with the greatest changes occurring in weight, texture, and taste. There were also differences between the tested cultivars. Statistically significant correlations between sensory and physicochemical data were observed between texture characteristics and weight changes. In case of sweet taste, only a weak correlation between the intensity of sweet flavour and soluble solid content values was found. No statistically significant correlation between the intensity of sour taste and titratable acidity was observed

Glycoform Analysis of Alpha1-Acid Glycoprotein by Capillary Electrophoresis Using Electrophoretic Injection

Human alpha1-acid glycoprotein (AGP) is an acute phase glycoprotein that has a heterogeneous glycosylation pattern. This pattern can change in certain diseases, which has resulted in interest in using AGP glycoforms as potential biomarkers for these diseases. This report describes a method that uses capillary electrophoresis to characterize and analyze AGP glycoforms both in purified samples of AGP and in human serum. This method uses static and dynamic coatings of poly (ethylene oxide) that are applied to a silica capillary for separation of AGP glycoforms in the reversed-polarity mode of CE and in the presence of negligible electroosmotic flow. Electrophoretic injection is performed onto such capillaries by using a stationary stacking interface between the sample and running buffer. In addition, acidic precipitation and desalting are used to allow for the isolation and the analysis of AGP from only 65 μL of serum. Up to eleven AGP glycoform bands can be reproducibly separated by this method, with the difference in migration time between neighboring bands being 12- to almost 60-fold larger than the standard deviation for the migration time of any given band. A limit of detection down to about 2 nM per glycoform band can be obtained by this method for AGP in serum based on absorbance detection and without the need for further sample modification or labeling