Search for: apple-juice
M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla ; Maghsoudi, Vida
This practice investigates about the resistance & sustainability of a sample of available microorganisms in fruit juices vs. a natural anti microbe called vanillin. To be more precisely the anti bacterial characteristic of vanillin has been tested against famous pathogenic organism Escherichia Coli in apple juice. The practice has been experienced for different concentrations of Vanillin, controlling & reducing the microbe concentration in apple synthetic juice. The effect has been investigated by measuring sensitivity of results in two different temperatures one in 8 degree of centigrade & other in 15, in each temperature two PH have been tested (PH = 3.5 & 4.5) 0-40-80 m-molar as 3...
Contribution of fouling and gel polarization during ultrafiltration of raw apple juice at industrial scale, Article Desalination ; Volume 258, Issue 1-3 , 2010 , Pages 194-200 ; 00119164 (ISSN) ; Tabatabaee Nezhad, S. A. R ; Soltanieh, M ; Roostaazad, R ; Khoshfetrat, A. B ; Sharif University of Technology
The flux behavior during the industrial cross-flow ultrafiltration of apple juice in a batch process was modeled using a combination of the fouling and concentration polarization models. It was observed that the major flux reduction was at the beginning and at the end of operation due to fouling and increasing solute concentration in the feed tank, respectively. The fouling phenomenon was analyzed by classical and empirical models and it was shown that the empirical one has the best correlation within less than 0.3% error for each experiment. The most significant advantage of this model is its ability to predict a steady flux, while other models predict zero flux at infinite time, which is...
M.Sc. Thesis Sharif University of Technology ; Roosta Azad, Reza ; Mousavi, Abbas
Many aroma compounds of fruit juice recovered by thermal evaporation and distillation processes can lead to undesirable chemical changes and even their loss. Pervaporation is a promising process for the recovery of volatile organic compounds from their aqueous solutions. In the present work, pervaporation recovery of Ethyl acetate as a model solution of apple juice’s aroma compound was evaluated with polyvinylidene fluoride (PVDF) and ethylvinylacetate (EVA) membranes. For PVDF and PES membranes in the feed concentration of 250-1000 ppm and the operating temperature of 30 ºC, separating factor , respectively, was obtained in the range of 67-70 and 49-53, and also total permeation flux was...
Article Separation and Purification Technology ; Volume 47, Issue 1-2 , 2005 , Pages 52-57 ; 13835866 (ISSN) ; Tabatabaeenezhad, A. R ; Roostaazad, R ; Khoshfetrat, A. B ; Sharif University of Technology
Declining permeate flux and increasing retentate solute concentration during a full scale apple juice ultrafiltration process was investigated. A modified equation and procedure was used for predicting retentate solute concentration (pectin) in the system. Solute concentration in the retentate was indirectly evaluated using the measured values of viscosity, temperature and Brix. The gel-polarization model was then used to analyze the collected data and a good agreement was observed between the experimental data and the model predictions. Fitted model parameters were very close to the published literature values for similar studies in pilot scale systems. According to the model, the optimum...
Article Chromatographia ; Volume 66, Issue 9-10 , 2007 , Pages 779-783 ; 00095893 (ISSN) ; Aghakhani, A ; EsHaghi, A ; Sharif University of Technology
A headspace solid-phase microextraction (HS-SPME) method was developed for the trace determination of geosmin in water and apple juice samples. A poly(dimethylsiloxane) (PDMS) fiber was synthesized as coated fiber using sol-gel methodology. After performing the extraction in the headspace, the fiber was introduced directly into the injection port of a gas chromatography-mass spectrometry (GC-MS) using electron impact (EI) ionization mode. One-at-the-time optimization strategy was applied to investigate and optimize important extraction parameters such as extraction temperature and time, ionic strength, headspace volume, and desorption temperature and time. The analytical data exhibited an...