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HPLC Method Development 5 June 2014 Volume 10 Issue 10 Cover Story 2 Sense and Sensitivity: The Role of Separation Science in Sensory Evaluation Kate Mosford of The Column spoke to Giorgia Purcaro of the Department of Food Science at the University of Udine, Italy, and Chiara Cordero of the Department of Drug Science and Technology at the University of Turin, Italy, about the sensory evaluation of olive oil and the benef ts of a comprehensive approach. Features 16 Principles of Detection and Characterization of Branching in HPLC GC MS SSPEynthetic IRand Natural Polymers by MALS Stepan Podzimek, SYNPO and University of Pardubice powered by This article provides insight into the basic principles of the MALS technique, and how it can be applied to the detection and characterization of branching in polymers. 20 Polyolefin Characterization by High Temperature Adsorption Liquid Chromatography: A Review of Solvent Gradient (SGIC) aEluennd Thte Crmhemistral Gradiyent Interaction Chromatography (TGIC) B. Monrabal, Polymer Char G The use of high temperature adsorption liqruadienid chromatography for the characterization of polyolef ns is detailed. t Elution 25 Using Multi-Detection GPC/SEC to Determine Impact of Sterilization on Medical-Grade Polymers Bassem Sabagh1 and Angel Valero-Navarro2, 1Malvern Instruments, 2nanoMyP Multi-detection GPC/SEC is described and new data showing how the technique is LIVE being used to determine the impact of sterilization on medical grade poly(L-lactide) is presented. on the web Regulars 10 News Optimization Text to come, text to come, text to come, text to come, text to come, text to come, text to come, text to come, text to come, text to come, text to come. Column 12 Tips & Tricks GPC/SEC: Selection The Art of Analyzing High Molar Mass Samples HPLC Method Daniela Held, PSS Polymer Standards Service GmbH GPC/SEC can be performed for samples that range from a few hundred to several million daltons in molar mass. It can often require more skill to analyze high molar mass samples in the molar mass range of several million dalton. DevelopmenHeadline_ hetadline_ This article explains more. F30ind CHROMac outademy more @ Subhead_ subhead_ subhead_ subhead Update on what’s new on the professional site for chromatographers. 31 Training Courses and Events Starts July 2014 www.CHROM33 Staff academy.com magentablackcyanyellow ES447539_LCTC060514_cvtp1.pgs 05.29.2014 18:21 ADV 5 June 2014 Volume 10 Issue 10 Cover Story 2 Sense and Sensitivity: The Role of Separation Science in Sensory Evaluation Kate Mosford of The Column spoke to Giorgia Purcaro of the Department of Food Science at the University of Udine, Italy, and Chiara Cordero of the Department of Drug Science and Technology at the University of Turin, Italy, about the sensory evaluation of olive oil and the benef ts of a comprehensive approach. Features 16 Principles of Detection and Characterization of Branching in Synthetic and Natural Polymers by MALS Stepan Podzimek, SYNPO and University of Pardubice This article provides insight into the basic principles of the MALS technique, and how it can be applied to the detection and characterization of branching in polymers. 20 Polyolefin Characterization by High Temperature Adsorption Liquid Chromatography: A Review of Solvent Gradient (SGIC) and Thermal Gradient Interaction Chromatography (TGIC) B. Monrabal, Polymer Char The use of high temperature adsorption liquid chromatography for the characterization of polyolef ns is detailed. 25 Using Multi-Detection GPC/SEC to Determine Impact of Sterilization on Medical-Grade Polymers Bassem Sabagh1 and Angel Valero-Navarro2, 1Malvern Instruments, 2nanoMyP Multi-detection GPC/SEC is described and new data showing how the technique is being used to determine the impact of sterilization on medical grade poly(L-lactide) is presented. Regulars 10 News Red wine could help to protect against dental cavities, HPLC–MS demonstrated as a clinical tool to monitor patients taking anti-hypertension drugs, and the New Orleans HPLC 2014 poster award winners are all featured in this issue. 12 Tips & Tricks GPC/SEC: The Art of Analyzing High Molar Mass Samples Daniela Held, PSS Polymer Standards Service GmbH GPC/SEC can be performed for samples that range from a few hundred to several million daltons in molar mass. It can often require more skill to analyze high molar mass samples in the molar mass range of several million dalton. Sense and Sensitivity This article explains more. 30 CHROMacademy The sensory evaluation of olive oil Update on what’s new on the professional site for chromatographers. 31 Training Courses and Events 33 Staff magentablackcyanyellow ES447483_LCTC060514_001.pgs 05.29.2014 18:16 ADV Sense and Sensitivity: The Role of Separation Science in Sensory Evaluation Kate Mosford of The Column spoke to Giorgia Purcaro of the Department of Food Science at the University of Udine, Italy, and Chiara Cordero of the Department of Drug Science and Technology at the University of Turin, Italy, about the sensory evaluation of olive oil and the benef ts of a comprehensive approach. Q: Olive oil is classif ed by law according therefore been subjected to frauds by the to both the chemical composition and addition of oils of lower quality and price. the sensory evaluation. Is olive oil the Since the f rst European Regulation only food product analyzed by sensory citing olive oil, which was enacted in 1966 evaluation? (Regulation no. 136/1966)1 and directed to Giorgia Purcaro: Sensory evaluation of market regulation on fats and oils within foods has been widely applied in industry Europe, both chemical and sensory evaluations to study consumer acceptance, which have been used for assessment of purity and inf uences business decisions and guides quality of olive oil. Although the def nitions of product development to get closer to sensory quality were initially “blurry” (“perfect a benchmark product. In academia the f avour”, “good f avour”, and “off-f avour”), correlation between sensory perception they were elucidated in detail in the European and chemical composition and texture has Regulation no. 2568, which was enacted in always been an important topic of study 1991. In fact, this regulation introduced — in food science. Sensory quality has been along with a long list of chemical analyses used as an additional requirement in several with an accurate description of the analytical food certif cations, such as PDO (product methods — a detailed explanation of the designation of origin). Sensory evaluation procedure to be performed in the training of has never been used as a legal parameter panellists, how to carry out the panel session, to def ne any kind of food products and the attributes to be used to evaluate the before olive oil. Olive oil has been a very sensory quality of olive oil.2 important product of the Mediterranean basin since ancient times, and it has always Q: What does the sensory evaluation been recognized, from both a quality and involve and what are the drawbacks? a commercial viewpoint, as high value oil GP: Sensory evaluation is fundamental Photo Credit: Ursula Alter/Getty Images compared to other vegetables oils. It has in classifying olive oil within the specif c 2 Q&A: Purcaro and Cordero 100 News 122 Tips & Tricks: GPC/SEC 16 Podzimek 2 20 Monrabal 25 Sabagh & Valero-Navarro 30 CHROMacademy 31 Training & Events 33 Staff magentablackcyanyellow ES447503_LCTC060514_002.pgs 05.29.2014 18:18 ADV The Column www.chromatographyonline.com Q&A: Purcaro and Cordero commercial class, namely extra virgin, virgin, since panellists are usually employed in other and lampante olive oil [Reg. CEE 2568/91, Reg jobs; (b) each session is very tiring, consequently CE 796/02; Reg CE 640/08].2–4 only a limited number of samples (maximum For example, extra virgin olive (EVO) oil, of six) can be analyzed for each session; apart from respecting all the required chemical (c) low reproducibility has been observed parameters, has to present a fruity aroma among different panels, mainly as a result of and no defects (muddy, fusty, rancid, musty, uneven training, which is related also to the vinegary, or metallic) that have originated diff cult availability of reference standards — in during olive or oil storage. Described in particular when presenting only one defect at a detail by both the European Regulation CEE time. Therefore, an objective sensory evaluation 2568/912 (and following modif cations) and is costly and time-consuming.8 by several International Olive Oil Council (IOC) documents (COI/T.20/Doc. No 15/Rev. 6; Q: What analytical techniques have been COI/T.20/Doc. No 13; COI/T.20/Doc. No 4),5–7 used to analyze olive oil previously and Is the foundation of your molecular characterization based on measurements without SEC-MALS? the sensory analysis is based on the judgement what are the benef ts of a comprehensive Scientists shouldn’t have to guess the molecular weights of their samples. But that’s pretty much what they do when they don’t of a panel of assessors, composed of a approach? use Wyatt’s SEC-MALS solutions to calculate molecular weights. Only Wyatt’s industry-leading DAWN® multi-angle light scattering (MALS) instruments make absolute molar mass determinations—without column calibration or reference minimum of eight testers (generally 12) headed GP: To study the volatile prof le of olive oil, the standards. When you connect a DAWN to your SEC/GPC system, you’ll determine absolute molar masses completely by a panel leader, who has to motivate the most suitable technique is gas chromatography independent of elution times. judges, process the data, interpret results, and (GC), usually coupled with a mass spectrometer Since 1982, we’ve been committed to solving the toughest macro molecular characterization problems for our customers. Every day, thousands of leading scientists throughout the world depend on our instruments.
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