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Interfering substances in the colorimetric quantitation of grape monoterpenes


, : Interfering substances in the colorimetric quantitation of grape monoterpenes. Hortscience 29(11): 1335-1336

The potential for interference by specific C-6 compounds in the colorimetric quantitation of grape (Vitis vinifera L.) monoterpenes was investigated in model solutions and muscat and neutral-flavored grape cultivars. The unsaturated C-6 aldehyde 2hexen-1-al (2HX) showed color absorption at 608 nm in distilled water after reaction with an acidified vanillin solution. Absorbance also increased significantly when 2HX was added to a series of linalool solutions; apprxeq 2.5 mg 2HX per liter of a 1-mg.liter-1 linalool solution increased the absorbance by gt 10%. Adding 2.5 mg 2HX per kilogram of 'Gewurztraminer' berry homogenate significantly increased apparent free volatile terpene (FVT) concentrations to 121% of unadulterated control treatments but did not affect potentially volatile terpenes (PVT). Adding 2HX also increased apparent FVT concentration in 'Perlette' and 'Flame Seedless'. Both neutral-flavored table grape cultivars contained some FVT and PVT as a consequence of their muscat ancestries. FVT and PVT quantitation by colorimetric methods may be subject to significant error if the concentration of 2HX and other unsaturated C-6 compounds in grape berries or must are gt 5 mg.liter-1. However, low concentrations of unsaturated C-6 compounds ( lt 80 mu-g.liter-1) in British Columbia wines suggest that there is a low probability of significant interference with this method.

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Other references

Kaiser, J.; Stockert, R.J.; Schein, P.S.; Wolkoff, A.W., 1986: Recognition of hepatitis B surface antigen by the human hepatoma cell line HepG2. Transactions of the Association of American Physicians 99: 86-91

Cook, C., B.; Tsui, C.; Ziemer, D., C.; Naylor, D., B.; Miller, W., J.; Hentz, J., G., 2006: Common reasons for hospitalization in urban diabetes patients. Objectives: Determine principal reasons for hospitalization in a predominantly urban, African American diabetes patient population.Design: Data for outpatients with a diagnosis of diabetes were abstracted from electronic records. The number of hos...

Shah V.; Miranda Q.R.; Mcbride J.H.; Diamond L.J.; Rodgerson D.O., 1982: Quantitation of slightly elevated levels of creatine kinase mb iso enzyme in human serum. Clinical Chemistry 28(7): 1618

Hu, R.; Barbault, F.; Maurel, Fçois.; Delamar, M.; Zhang, R., 2011: Molecular dynamics simulations of 2-amino-6-arylsulphonylbenzonitriles analogues as HIV inhibitors: interaction modes and binding free energies. Molecular dynamics (MD) simulations in water environment were carried out on the HIV-1 reverse transcriptase (RT), and its complexes with one representative of each of three series of inhibitors: 2-amino-6-arylsulphonylbenzonitriles and their thio...

Renders, G.; Oosterlinck, W., 1972: Exceptional foreign body of the bladder. Acta Urologica Belgica 40(4): 830-832

Sule, M.; Jungmann, R., 1980: Immune reactions in coccidiosis of chickens and tendencies for their practical application. A review is given of the immunity to coccidiosis which may be produced in chickens especially by subpatent infection partly controlled by anticoccidial drugs. If drug-resistance becomes more common in coccidia, protection by immunization may becom...

Mangun, J.C.; Huennekens, D.R., 1999: Angling for catfish and bullheads in the Midwest Structure and specialization. Irwin, Elise R , Hubert, Wayne A , Rabeni, Charles F , Schramm, Harold L , Jr , Coon, Thomas American Fisheries Society Symposium Catfish 2000: Proceedings of the International Ictalurid Symposium : 506

Anonymous, 1957: Progress reports from experiment stations, season 1955-56. The general trend of husbandry results at Ukiriguru and Lubaga followed that of previous years. Consequently it is recommended that on the hill-sand areas of the Province any cattle manure available should be fully used, and where insufficient is...

Nash J.T.omas; Trudel Wayne, 1994: Sleeper gold-silver deposit, Humboldt County, Nevada; importance of Miocene extensional tectonics. U S

Olsson, J.; Kammerlind, P.; Thor, J.; Elg, M., 2003: Surveying improvement activities in health care on a national level--the Swedish internal collaborative strategy and its challenges. In order to map improvement activities in Swedish health care, we surveyed the managers of all primary health care centers (n = 958) and clinical hospital departments (n = 1355), with a response rate of 46%. The majority reports that their staff v...