Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Ateneo de Manila University

Chemistry Faculty Publications

2011

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

Analysis Of Volatile Organic Compounds In Virgin Coconut Oil And Their Sensory Attibutes, Fabian M. Dayrit, Jaclyn Elizabeth R. Santos, Bianca J. Villarino, Anthony R. Zosa Dec 2011

Analysis Of Volatile Organic Compounds In Virgin Coconut Oil And Their Sensory Attibutes, Fabian M. Dayrit, Jaclyn Elizabeth R. Santos, Bianca J. Villarino, Anthony R. Zosa

Chemistry Faculty Publications

The volatile compounds in the headspace of twenty-four commercial virgin coconut oil (VCO) samples prepared by different methods (i.e. expeller, centrifugation, and fermentation with and without heat) were analyzed by solid phase microextraction-gas chromatography mass spectrometry (SPME-GCMS). The following volatile organic compounds (VOCs) were identified: ethyl acetate, acetic acid, 2-pentanone, hexanal, n-octane, 2-heptanone, limonene, nonanal, octanoic acid, ethyl octanoate, δ-octalactone, ethyl decanoate, δ-decalactone, and dodecanoic acid. Fermentation-produced samples were found to have higher levels of acetic acid and free fatty acids in the headspace compared to VCO produced using the centrifuge and expeller methods. Descriptive sensory analysis of the VCO …

Go to article

Opacity Of P(Mma-Maa)-Pmma Composite Latex System With Varying Maa Concentration, Gilbert U. Yu, Jerry T. Dy, Erwin P. Enriquez Dec 2011

Opacity Of P(Mma-Maa)-Pmma Composite Latex System With Varying Maa Concentration, Gilbert U. Yu, Jerry T. Dy, Erwin P. Enriquez

Chemistry Faculty Publications

Polymer composites of core-shell morphology are commonly used in the paint industry as opacity enhancer. These are usually made of block copolymer systems wherein the core is formed from a polymer that swells in the presence of a solvent and surrounded by a high glass transition polymeric shell. Thus, upon drying, the swollen regions turn into voids while leaving a hard shell. Here, composites based on poly(methyl methacrylate-butyl acrylate) [P(MMA-BuA)] (seed stage), poly(methyl methacrylate-methacrylic acid) [P(MMA-MAA)] (second stage), and poly(methyl methacrylate) [PMMA] (third stage) were synthesized through a multistage sequential emulsion polymerization and their opacity was investigated. The second stage …

Go to article

Physico-Chemical And Microbiological Parameters In The Deterioration Of Virgin Coconut Oil, Ian Ken D. Dimzon, Melodina F. Valde, Jaclyn Elizabeth R. Santos, Mark Joseph Garrovillas, Henson M. Dejarme, Jo Margarette W. Remollo, Fabian M. Dayrit Jun 2011

Physico-Chemical And Microbiological Parameters In The Deterioration Of Virgin Coconut Oil, Ian Ken D. Dimzon, Melodina F. Valde, Jaclyn Elizabeth R. Santos, Mark Joseph Garrovillas, Henson M. Dejarme, Jo Margarette W. Remollo, Fabian M. Dayrit

Chemistry Faculty Publications

The deterioration of virgin coconut oil (VCO) due to physico-chemical oxidation and hydrolysis and microbiological processes was studied. The physico-chemical oxidation of VCO in the air at room temperature was negligible. Oxidation of VCO was observed only in the presence of air, UV radiation, ferric ion (Fe3+), and high free fatty acid (FFA) content. Chemical hydrolysis was performed at varying moisture levels and temperatures. The rate of hydrolysis to produce FFAs was measured using 31P NMR under conditions of saturated water (0.22%) and 80°C was found to be 0.066 µmol/g-hr (expressed as lauric acid). At 0.084% moisture and 80°C, the …

Go to article

Novel Glycerol-Crosslinked Poly(Acrylic Acid) Hydrogel For Encapsulation And Release Of Benzocaine, Angela Lisandra S. Lee, Gayzen A. Ordoñez, Soma Chakraborty Jan 2011

Novel Glycerol-Crosslinked Poly(Acrylic Acid) Hydrogel For Encapsulation And Release Of Benzocaine, Angela Lisandra S. Lee, Gayzen A. Ordoñez, Soma Chakraborty

Chemistry Faculty Publications

Drug delivery by a controlled-release mechanism offers several advantages over traditional delivery systems such as improved therapeutic activity, reduced number of drug administrations, as well as minimizing the risk of over-dose or under-dose. In this study, attempt has been made to develop a novel controlled release device from glycerol crosslinked poly(acrylic acid) hydrogels. Glycerol crosslinked poly(acrylic acid) was fabricated by polymerizing acrylic acid and crosslinking the polymer with glycerol in the same reaction pot in the presence of benzoyl peroxide and Novozym 435. The fabricated hydrogel swelled more than 100% in neutral, acidic and basic buffer solutions. Swelling was pH …

Go to article

Quality Characteristics Of Virgin Coconut Oil:Comparisons With Refined Coconut Oil, Fabian M. Dayrit, Ian Ken D. Dimzon, Melodina F. Valde, Jaclyn Elizabeth R. Santos, Mark Joseph Garrovillas, Blanca J. Villarino Jan 2011

Quality Characteristics Of Virgin Coconut Oil:Comparisons With Refined Coconut Oil, Fabian M. Dayrit, Ian Ken D. Dimzon, Melodina F. Valde, Jaclyn Elizabeth R. Santos, Mark Joseph Garrovillas, Blanca J. Villarino

Chemistry Faculty Publications

Virgin coconut oil (VCO) is a vegetable oil that is extracted from fresh coconut meat and is processed using only physical and other natural means. VCO was compared to refined, bleached, and deodorized coconut oil (RCO) using standard quality parameters, 31 P nuclear magnetic resonance (NMR) spectroscopy, and headspace solid-phase micro - extraction/gas chromatography mass spectrometry (SPME/GCMS). VCO tends to have higher free fatty acids (FFAs), moisture, and volatile matter and lower peroxide value than RCO. However, the range of values overlap and no single standard parameter alone can be 31 used to differentiate VCO from RCO. Using 31P NMR, …

Go to article