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Protein/sugar Mixtures (sugar + mixture)
Selected AbstractsFreeze-dry microscopy of protein/sugar mixtures: Drying behavior, interpretation of collapse temperatures and a comparison to corresponding glass transition DataJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 9 2009Eva Meister Abstract The purpose of this study is to investigate the change in collapse appearance and temperature of protein/sugar mixtures as a function of nucleation temperature (Tn), sublimation velocity (Vsub) and the sugar/protein mole ratio when performing freeze-dry microscopy experiments. BSA and HSA were used as sample proteins and mixed with either sucrose or trehalose. Differential scanning calorimetry was used to determine the corresponding glass transition temperatures . To allow a more representative comparison between these analytical methods, a collapse midpoint temperature (Tc-50) was introduced. While there was no distinct correlation between Tn and the onset of collapse (Toc) for either mixture, Vsub was found to correlate with the measured collapse temperature which is important for comparability of experiments. Furthermore, Vsub could be used to qualitatively investigate the product resistance to water vapor flow. A dramatic change in the appearance of collapse was found for high sugar/protein mole ratios (,362:1) which needs to be considered to avoid a misinterpretation of Toc data. At low protein concentrations midpoint data showed good agreement with Toc values but were found significantly lower at higher protein concentrations. Application of the Gordon,Taylor equation failed to predict the critical temperature for any of the protein/sugar mixtures studied. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:3072,3087, 2009 [source] Rapid Analysis of Glucose, Fructose, Sucrose, and Maltose in Honeys from Different Geographic Regions using Fourier Transform Infrared Spectroscopy and Multivariate AnalysisJOURNAL OF FOOD SCIENCE, Issue 2 2010Jun Wang ABSTRACT:, Quantitative analysis of glucose, fructose, sucrose, and maltose in different geographic origin honey samples in the world using the Fourier transform infrared (FTIR) spectroscopy and chemometrics such as partial least squares (PLS) and principal component regression was studied. The calibration series consisted of 45 standard mixtures, which were made up of glucose, fructose, sucrose, and maltose. There were distinct peak variations of all sugar mixtures in the spectral "fingerprint" region between 1500 and 800 cm,1. The calibration model was successfully validated using 7 synthetic blend sets of sugars. The PLS 2nd-derivative model showed the highest degree of prediction accuracy with a highest,R2 value of 0.999. Along with the canonical variate analysis, the calibration model further validated by high-performance liquid chromatography measurements for commercial honey samples demonstrates that FTIR can qualitatively and quantitatively determine the presence of glucose, fructose, sucrose, and maltose in multiple regional honey samples. [source] MODELING OF SWEET, BITTER AND IRRITANT SENSATIONS AND THEIR INTERACTIONS ELICITED BY MODEL ICE WINESJOURNAL OF SENSORY STUDIES, Issue 5 2006CANAN NURGEL ABSTRACT Interactions between taste and irritant sensations elicited by model ice wine solutions were investigated, including the use of U and ,, models for predicting the perceived intensity of these sensory interactions. Fifteen solutions of varying ethanol and sugar concentrations representative of commercial ice wine values were evaluated in two trials by a trained sensory panel (n = 12) for perceived sweetness, bitterness and heat intensities. Sweetness perception of lower sugar-concentration level in ice wine model solution was affected by ethanol concentration. The sweetness intensities of the sugar and ethanol mixtures are higher than the sweetness intensities of sugar solutions. The ,, index indicates a slight synergy between ethanol and sugar on sweetness perception. The bitterness intensities elicited by ethanol,sugar mixtures are lower than those elicited by unmixed ethanol solutions. The ,, index indicates inhibition of ethanol and sugar perception on bitterness perception. Suppression of heat sensation was found in model base wine solutions across sugar and ethanol concentrations. [source] | ||||||||||