Trace Analysis of Precious Drops
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worldwide SPECIAL EDITION GERSTEL GmbH & Co. KG · Eberhard-Gerstel-Platz 1 · 45473 Mülheim an der Ruhr / Germany · Phone +49 208 76503-0 · E-Mail: gerstel @ gerstel.com Modern Wine Analysis Trace analysis of precious drops Research Searching for the pepper in Shiraz Off flavors in wine Watch your sulfurs! Research The Twister sniffs out the aftertaste Modern wine analysis Content Modern wine analysis It’s not all about adulteration 2 Archaeology meets chemistry Peeking into Pharaoh’s wine glass 3 It’s not all about Research The Twister sniffs out the aftertaste 6 Pesticide analysis EZ adulteration Searching for the pepper in Shiraz 9 Lab on the slopes Prof. Dr. Manfred Grossmann Flavor from trash cans 12 Advanced Flavor and Fragrance Analysis An extra GC dimension at your finger tips 14 Degustation ine has been a permanent fixture in the microbiology and wine analysis. Consequently, Tasting a wine beats reading about it… 16 Whistory of mankind for more than 7,000 modern wine analysis is not just about years. The grape juice fermentation product is enlisting the help of traditional tools such as Off Flavors in Wine part I: Corky today justly described as a cultural heritage. spectroscopy, chromatography, photometry Efficient and sensitive determination of TCA and other off-flavors 17 Surely wine producers have always worked and electrochemistry; we must also rely on hard to improve the already high quality of their biochemical and molecular biology methods. Off flavors in wine part II: product, making sure that it stays fresh longer It would be a mistake to believe, however, Sulfur related flavors – reductive notes or improving the flavor and taste to make it that simply detecting genes and determining Watch your sulfurs! 20 more appealing. Equally, through the ages, and regulating expression rates is the road Twister extraction wine producers have regularly been spiking to fruitful knowledge. In the age of “-omics”, Two is company 24 wine with low cost ingredients to lower the Genomics, Transcriptomics and Metabolomics, Extraction techniques cost while making the wine appear of better detecting genes and determining and regulating HIT it - targeting VOCs and SVOCs 29 quality than it is. A Phoenician tombstone their expression rates is no longer sufficient. Literature dating back to 1,000 A.C. states: You shall A comprehensive determination of the Suggested reading… 32 not perform magic on your neighbor’s wine. metabolites formed during cellular activities on Fatal side effects experienced from using lead the vine and during fermentation is required; worldwide sugar as a sweetener gave rise to serious wine for the wine, these are the primary quality SPECIAL EDITION GERSTEL GmbH & Co. KG · Eberhard-Gerstel-Platz 1 · 45473 Mülheim an der Ruhr / Germany · Phone +49 208 76503-0 · E-Mail: gerstel @ gerstel.com analysis as of the 17th century. However, those determining flavor compounds. Meanwhile Modern Wine Analysis Trace analysis of who claim that wine analysis is just a means of oenologists world-wide are also learning to precious drops detecting illegal techniques or additives are not weave a systematic web using various highly Research delving deep enough into the matter. Modern different individual analyses and leading the Searching for the pepper in Shiraz Off flavors in wine Watch your sulfurs! wine science makes use of a wide range of way to a Systems Biology approach. This is Research The Twister sniffs out the aftertaste instrumental analysis techniques and methods. a comprehensive research approach that the These enable the scientist to determine Geisenheim Research Center among others the origin of the key taste and flavor has put into practice in order to safeguard a compounds in the grapes and to follow the millennia old cultural heritage and to benefit Imprint underlying metabolism processes every step the consumer. of the way during the various technical and Published by microbiological stages in the wine making Prof. Dr. Manfred GERSTEL GmbH & Co. KG process. Nevertheless, wine chemists are Grossmann is Vice- Eberhard-Gerstel-Platz 1 often faced with challenges that require new Chairman of the 45473 Mülheim an der Ruhr, Germany approaches and new solutions. In recent years Institute of Oenol- Editorial Director it was increasingly found, that compounds ogy and Beverage Guido Deußing which are odor active in the final wine are Research and Chair- man of the Depart- ScienceCommunication initially not detected in sensory tests. Neuss, Germany ment of Biology This is due to the fact that they are bound [email protected] and Microbiology, to short chain saccharides or peptides during one of the oldest Translation and editing their formation in the grape vines. The side Kaj Petersen research centres in the German speak- chains are subsequently split off by the yeasts [email protected] ing countries. Professor Grossman is a during alcoholic fermentation, but hydrolysis member of the Board of Wine Research, Scientific advisory board is not the only thing that is happening. consulting the German Federal Ministry Eike Kleine-Benne, Ph.D. Through additional biochemical modifications of Nutrition, Agriculture and Consumer [email protected] performed by the yeast during the fermentation Protection; Consultant for the Federal Oliver Lerch, Ph.D. process, new and modified flavor compounds Ministry of Education and Research as [email protected] well as external reviewer for the Univer- 2018 are created that give rise to different taste / Malte Reimold, Ph.D. sity of Stellenbosch. (South Africa). Since and flavor impressions. This means that the [email protected] 1996 Professor Grossmann has been Contact micro-organisms have significant influence on German delegate to the expert commit- [email protected] the wine flavor. A full and clear picture of the tee „Microbiology of Wine“ of the Inter- Design sensory aspects of a wine is only bestowed national Organization of Vine and Wine Paura Design, Hagen, Germany upon those that succeed in playing the entire (OIV) and has been vice-chairman of this range of instruments available for both wine committee since 2004. www.paura.de ISSN 1619-0076 · 05 2 GERSTEL Solutions Worldwide Wine Special and his contemporaries imbibed when “communicating” with the wine gods. The uncovered amphorae have been completely dry and empty; the wine evaporated an eternity ago. Not until chemists were called upon to inspect the grave goods more closely did hard facts begin to emerge. In the amphorae found in the grave of Tutankhamen, malvidine-3- Polyphenols are universally praised for their positive health effects, in large part ascribed to antioxidant and radical scavenging proper- ties. One might also turn to grapes, raisins, black currants, cranberries or elderberries for a less stimulating source. Most chemical research on polyphenols is reportedly per- formed on wine. glucoside was identified among the remains (Armen Mirzoian et al., „Analytical Chemistry“, Vol. 76, No. 6, March 15, 2004). This compound is one of the more stable Archaeology meets chemistry anthocyanins, the group of compounds that lends a warm red hue to the class of wines known as red wines. The 18 year old Pharaoh, Peeking into Pharaoh’s in other words, had been given amphorae of red wine to accompany him, possibly wine * that he had favored during his short life. As glass an aside, anthocyanins form the main group of flavonoids that, along with phenols, make up the class polyphenols, which are thought * Ancient Egyptian sign for „Wine“ to have positive health effects. Equally scientifically intriguing was the Details on viticulture in ancient Egypt are quite well understood by search for wine residues in 700 wine jugs modern-day archaeologists. But what exactly was in Pharaoh’s glass found in Abydos, Egypt. The jugs had been dated to 3,150 B.C., around 1,800 years prior when he savored the gift of the wine gods – and was it just imbibed for to the birth of Tutankhamen. They were relaxation and merriment or was it taken as a stimulating aphrodisiac found in what was probably the tomb of the first Egyptian Pharaoh, Scorpion, from the or maybe prescribed by his physician to cure or alleviate pharaohnic first dynasty. Initial research had revealed that ailments? Answers to these questions have eluded us for ages. When the Abydos jugs had contained around 4,000 Liters (1,000 Gallons) of wine from the Valley archaeologists recently consulted analytical chemists armed with of Jordan, about 600 km (400 miles) away. thermal desorption GC/MS systems, information began to trickle out, The project described here was offering insight into ingredients used in ancient Egyptian wine. performed by scientists from the Museum of the University of Pennsylvania (MASCA) ine from ancient Egypt is thought to “wine”, archaeologists were able to determine W have been honey-sweet – though now that grapes were being grown and wine it is just bone-dry. What was once refreshing, produced as early as 3,000 B.C. in the Nile stimulating and thirst-quenching has mostly Delta (Lower Egypt). At that point a thriving evaporated; only dust and residues remain in wine-producing industry controlled by the the 3-5 millennia old amphorae that were rulers had already taken root. Vines were found in the tombs of those ancient rulers planted in pits filled with fertile Nile river and demigods, the Pharaohs. On their way silt. Given sufficient irrigation, vines could to the netherworld, they were given gold and be grown successfully in oases. ample riches along with food and amphorae filled with precious wine. One amphora Sacrifices to the gods was marked: “Year 5. Wine of the House of Tutankhamen, Ruler of-the Southern On, the Western River. By the chief Vintner Khaa.’’ Archaeologists have found evidence that wine (Source BBC). was well appreciated for festive occasions in Some tombs are embellished with wall ancient Egypt.