Food Engineering / Gıda Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/12
Browse
3 results
Search Results
Article Citation - WoS: 3Citation - Scopus: 3Evaluation of High Hydrostatic Pressure Effects on Bovine Red Blood Cells and Platelets(Taylor and Francis Ltd., 2009) Ceylan, Çağatay; Severcan, Mete; Bozoğlu, Faruk; Severcan, FerideThe objective of this study was to investigate the effects of high hydrostatic pressure (HHP) on the stability of red blood cells (RBCs) and platelets. Bovine blood cells (n=5) were treated with the pressure of 55, 110, 154 and 220MPa at 25°C for 5min. Light microscopy, atomic force microscopy and flow cytometry studies revealed that RBCs were morphologically stable up until the 220MPa pressure treatments, at which surface modifications were observed. The platelets were found to be less stable than RBCs. HHP application did not cause any significant change in the signal intensity, band area and frequency values of the infrared bands with the exception that a significant variation was observed in the area of the cholesterol band. No statistically significant variations were observed in the secondary structure elements due to HHP treatment according to the artificial neural network study based on the FTIR data.Article Citation - WoS: 68Citation - Scopus: 76Differentiation of Mixtures of Monovarietal Olive Oils by Mid-Infrared Spectroscopy and Chemometrics(John Wiley and Sons Inc., 2007) Gürdeniz, Gözde; Tokatlı, Figen; Özen, Fatma BanuFourier transform infrared (FT-IR) spectroscopy in combination with chemometric techniques has become a useful tool for authenticity determination of extra-virgin olive oils. Spectroscopic analysis of monovarietal extra-virgin olive oils obtained from three different olive cultivars (Erkence, Ayvalik and Nizip) and mixtures (Erkence-Nizip and Ayvalik-Nizip) of monovarietal olive oils was performed with an FT-IR spectrometer equipped with a ZnSe attenuated total reflection sample accessory and a deuterated tri-glycine sulfate detector. Using spectral data, principal component analysis successfully classified each cultivar and differentiated the mixtures from pure mono-varietal oils. Quantification of two different monovarietal oil mixtures (2-20%) is achieved using partial least square (PLS) regression models. Correlation coefficients (R2) of the proposed PLS regression models are 0.94 and 0.96 for the Erkence-Nizip and Ayvalik-Nizip mixtures, respectively. Cross-validation was applied to check the goodness of fit for the PLS regression models, and R 2 of the cross-validation was determined as 0.84 and 0.91, respectively, for the two mixtures.Article Citation - WoS: 39Citation - Scopus: 49Production of Antimicrobial Films by Incorporation of Partially Purified Lysozyme Into Biodegradable Films of Crude Exopolysaccharides Obtained From Aureobasidium Pullulans Fermentation(University of Zagreb, 2005) Kandemir, Nilay; Yemenicioğlu, Ahmet; Mecitoğlu, Çiğdem; Elmacı, Zehra Seda; Arslanoğlu, Alper; Göksungur, Mehmet Yekta; Baysal, TanerAntimicrobial films were produced by incorporating partially purified lysozyme into films of crude exopolysaccharides (59% pullulan) obtained from Aureobasidium pullulans fermentation. After film making, the films containing lysozyme at 100, 260, 520 and 780 μg/cm2 showed 23 to 70% of their expected enzyme activities. The highest recovery of enzyme activity (65-70%) after the film making was obtained in films prepared by incorporating lysozyme at 260 μg/cm2 (1409 U/cm2). The incorporation of disodium EDTA·2H2O and sucrose did not affect the initial lysozyme activity of the films significantly. With or without the presence of disodium EDTA·2H2O at 52 or 520 μg/cm2, lysozyme activity showed sufficient stability in the films during 21 days of cold storage. However, the presence of sucrose at 10 mg/cm2 in the films caused the destabilization of part of enzyme activity (almost 35%) at the end of storage. The combinational incorporation of lysozyme at 780 μg/cm 2 (4227 U/cm2) and disodium EDTA·2H2O at 520 μg/cm2 gave antimicrobial films effective on Escherichia coli. However, in the studied lysozyme concentration range the films did not show any antimicrobial activity against Lactobacillus plantarum. This study clearly showed that the partially purified lysozyme and crude exopolysaccharides from Aureobasidium pullulans may be used to obtain antimicrobial films to increase the safety of foods.
