Indiana University-Purdue University Indianapolis (IUPUI) / Solid phase micro-extraction is a powerful and versatile technique, well-suited to the analysis of numerous samples of forensic interest. The exceptional sensitivity of the SPME platform, combined with its adaptability to traditional GC-MS systems and its ability to extract samples with minimal work-up, make it appropriate to applications in forensic laboratories. In a series of research projects, solid phase micro-extraction was employed for the analysis of explosives, commercial tire treatments, and entomological specimens. In the first project, the volatile organic compounds emanating from two brands of pseudo-explosive training aids for use in detector dog imprinting were determined by SPME-GC-MS, and the efficacy of these training materials was tested in live canine trials. In the second project, the headspace above various plasticizers was analyzed comparative to that of Composition C-4 in order to draw conclusions about the odor compound, 2- ethyl-1-hexnaol, with an eye toward the design of future training aids. In the third, automobile tires which had participated in professional race events were analyzed for the presence of illicit tire treatments, and in the fourth, a novel SPME-GC-MS method was developed for the analysis of blowfly (Diptera) liquid extracts. In the fifth and final project, the new method was put to the task of performing a chemotaxonomic analysis on pupa specimens, seeking to chemically characterize them according to their age, generation, and species.

No description available.

No description available.

The relationships between volatile flavor compounds, sensory descriptors and consumer acceptability were determined for eight commercial American dry-cured hams using external preference and flavor mapping. The majority of consumers preferred (p<0.05) hams that had more intense caramelized, smoky, savory and molasses aromas as well as more intense sweet and savory flavors. Sixteen aroma impact compounds were identified from the headspace volatiles of dry-cured hams. The consumers with the highest acceptability scores preferred (p<0.05) hams that were characterized by 4-methyl-2-methoxyphenol (sweet ham), 4-ethyl-2-methoxyphenol (sweet ham), 2-methoxyphenol (smoky, cocoa), 2,6-dimethoxyphenol (smoky ham, savory) and 2uranmethanol (burnt meat, vitamin). Fourteen percent of consumers preferred (p<0.05) two hams that were characterized by methional (baked potato). Consumer acceptability scores were lower for hams either characterized by methanethiol (sulfur), carbon disulfide (sulfur), 2-butanone (sweet), 3-methylbutanal (malty, fermented), 2-heptanone (burnt meat, vitamin), hexanal (cut grass), benzeneacetaldehyde (floral), 1-octen-3-ol (mushroom) or characterized by benzaldehyde (burnt meat, cooked meat) and limonene (citrus).

No description available.

No description available.

No description available.

No description available.

Nesta pesquisa está sendo investigada, pela primeira vez, a composição química de lúpulos cultivados no Brasil para a produção de cervejas artesanais. Para isso, foram analisadas 10 amostras de lúpulos das variedades cascade, columbus, chinook e hallertauer, cultivados em diferentes regiões do Brasil (Minas Gerais, Paraná e Rio Grande do Sul). Quando foram comparadas as composições químicas dos lúpulos cultivados no Brasil com lúpulos comerciais produzidos em outros países, verificou-se que o lúpulo da variedade cascade produzido em Araxá - MG era o que apresentava maior similaridade ao produto comercial. O cascade nacional apresentou teores de humulonas e lupulonas de 4% e 3%, respectivamente. Quanto aos teores de óleo essencial, o cascade nacional apresentou um rendimento de 1,2 % (v/m). Os principais constituintes do óleo essencial deste lúpulo foram: mirceno (59%), 2-metilbutil isobutirato (0,7%), linalol (0,5%), &beta;-cariofileno (4%), &alpha;-humuleno (15%) e &alpha;-farneseno (1%). Após esta triagem, o lúpulo cascade nacional foi utilizado para fabricação de uma cerveja artesanal, sendo que, em paralelo foi também fabricada uma cerveja artesanal com o lúpulo cascade comercial (controle), a fim de comparar o efeito da origem do lúpulo na composição química de voláteis e iso-humulonas nas cervejas produzidas. Além disso, também está sendo investigado o efeito da adição de uma enzima beta-glicosidase na liberação de terpenos provenientes do lúpulo nas cervejas fabricadas com o lúpulo cultivado no Brasil e com o lúpulo comercial. Para análise dos voláteis da cerveja foi otimizada, por metodologia de superfície de resposta, a etapa de extração dos voláteis empregando micro-extração em fase sólida de headspace (HS-SPME). As condições ótimas de extração foram: fibra CAR/DVB/PDMS, temperatura de extração de 75 °C por 121 minutos. As cervejas produzidas apresentaram diferenças na composição dos seus voláteis, e no aroma avaliado em uma degustação as cegas. Aquelas cervejas elaboradas com enzima apresentaram aromas mais intensos que as elaboradas sem enzima &beta;-glicosidase, o que pode ser explicado pela maior quantidade de certos terpenos nestas cervejas, o que sugere a existência de terpenos glicosilados nos lúpulos empregados. Quanto aos teores de iso-humulonas nas cervejas, embora estes compostos foram quantificados nas quatro cervejas elaboradas, não foi possível comparar os resultados por um possível erro na etapa de lupulagem durante a elaboração das cervejas. / In this research the chemical composition of cascade, columbus, chinook and hallertauer hops, cultivated in different regions of Brazil (Minas Gerais, Paraná and Rio Grande do Sul) are being investigated for chemical composition for the first time. When comparing the chemical compositions of Brazilian hops with commercial hops produced in other countries, it was verified that the cascade variety produced in Araxá city (MG) were the most similar to the commercial products. The cascade cultivated in Brazil presented levels of humulones and lupulones of 4% and 3%, respectively. Regarding the essential oil contents, cascade cultivated in Brazil showed a yield of 1.2% (v/w). The main constituents of the essential oil of this hop were: &beta;-mycene (59%), 2-methylbutyl isobutyrate (0.7%), linalool (0.5%), &beta;-caryophyllene (4%), &alpha;-humulene and &alpha;-farnesene (1%). After this sceening, the cascade cultivated in Brazil were used to make a craft beer, and in parallel was also made a craft beer with commercial cascade hop (control), in order to compare the effect of hops origin on volatiles chemical composition and on iso-humulones content in the beers produced. In addition, the effect of &beta;-glucosidase, an enzyme which catalyses the hydrolysis of terminal non-reducing residues in &beta;-glucosidese (EC number: 3.2.1.21), on the release of hop volatiles (from glicoside terpenes) to beers is also being investigated. For the beer volatile analysis, the extraction step by headspace solid phase microextraction (HS-SPME) was optimized by response surface methodology. The optimal extraction conditions were: CAR/DVB/PDMS fiber, and extraction temperature of 75 °C for 121 minutes. The beers produced showed differences in the composition of their volatiles, and in the aroma evaluated in a blind sensory test. The beers made with enzyme showed more intense aromas than those made without &beta;-glucosidase, which can be explained by the greater amount of certain terpenes in these beers, which suggests the existence of glycosylated terpenes in the hops. Regarding the iso-humulone levels in the beers, although these compounds were quantified in the elaborated beers, it was not possible to compare the results by a possible error in the hopping stage during brewing.

Foi desenvolvido um método para determinar canabinóides (canabidiol, canabinol e delta-9-tetraidrocanabinol) no cabelo. Uma amostra de 10mg foi descontaminada com diclorometano, seguida de digestão alcalina, microextração em fase sólida por headspace (HS-SPME) e analisada por espectrometria de massa associada à cromatografia em fase gasosa (GC/MS). Os limites de detecção e de quantificação foram de 0,07 e 0,12 ng/mg, respectivamente, para todos canabinóides estudados. O método demonstrou ser simples, rápido, preciso e linear no intervalo de 0,12 a 12 ng/mg (r2 > 0,98). Amostras de cabelo de 8 usuários de Cannabis foram coletadas de pacientes provenientes de uma clínica dependentes pela equipe médica. O método mostrou-se eficiente em amostras de cabelos de usuários que faziam uso da droga pelo menos 10 vezes por semana. / A method was to develop to detect cannabinoids (cannabidiol, cannabinol and delta-9-tetrahydrocannabinol) in hair. A 10 mg of hair sample was descontaminated by dichloromethane followed by alkalin digestion, headspace solid-phase microextraction technique (HS-SPME) and analyzed by gas chromatography-mass spectrometry (CG/MS). The detection and quantitation limits were 0,07 and 0,12ng/mg respectively for all studied cannabinoids. The method proved to be simple, fast, precise and linear at the range of 0,12 to 12ng/mg (r2 > 0,98). Eight hair samples of Cannabis user were collected from patients at admittance from a dependence clinic by clinical staff. The method showed efficient in samples of users who use the drug at least 10 fold a week.