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1.
J Food Sci Technol ; 56(6): 2874-2887, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31205343

RESUMO

The effects of indigenous fermentation on volatile compound profiles in a Theobroma cacao L, TSH565 clone, resistant to Moniliophtora perniciosa and Phytophthora spp. were evaluated in Southern Brazil. Sixty-three volatile flavor compounds in pulp and 36 in grains were identified by SPME-HS/GC-MS and classified as terpenes, alcohols, esters, ketones and aldehydes, among others. The relative amount of these compounds and their evolution until the end of the fermentation process were assessed in both fresh and fermented grains/pulp masses. ß-myrcene and ß-cis-ocimene, among terpenes, were detected in high amounts and are associated to a fine chocolate aroma. The sensory evaluation of chocolates manufactured from the fermented cocoa was performed by trained panelists, which defined 15 sensory descriptors. Chocolates from the TSH565 cultivar were characterized by a rich, fruity, intense cocoa flavor and bitterness, which are valuable sensorial and commercial attributes.

2.
Food Chem ; 219: 13-22, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27765208

RESUMO

The volatile fraction of murici, bacuri and sapodilla are here studied because of their increasing interest for consumers, abundance of production in Brazil, and the general demand for new flavors and aromas. Their volatile profiles were studied by two High Concentration Capacity Headspace techniques (HCC-HS), Headspace Solid Phase Microextraction (HS-SPME) and Headspace Sorptive Extraction (HSSE), in combination with GC-MS. Murici volatile fraction mainly contains esters (38%), carboxylic acids (19%), aldehydes (11%), alcohols (14%), others (13%) and sulfur compounds; bacuri is characterized by terpenes (41%), non-terpenic alcohols (24%), esters (15%), aldehydes (6%), and others (12%); sapodilla consists of esters (33%), alcohols (27%), terpenes (18%) and others (21%). The GC-MS component co-elution was overcome by GC×GC-qMS. The adoption of modern analysis technologies afforded to achieve a better knowledge of the volatile fraction composition of these fruit pulps by increasing substantially the number of compounds identified.


Assuntos
Clusiaceae/química , Frutas/química , Malpighiaceae/química , Manilkara/química , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise , Brasil
3.
J Chromatogr A ; 1477: 91-99, 2016 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-27912967

RESUMO

Improved separation of both sesquiterpenes and diterpenic acids in Copaifera multijuga Hayne oleoresin, is demonstrated by using comprehensive two-dimensional gas chromatography (GC×GC) coupled to accurate mass time-of-flight mass spectrometry (accTOFMS). GC×GC separation employs polar phases (including ionic liquid phases) as the first dimension (1D) column, combined with a lower polarity 2D phase. Elution temperatures (Te) of diterpenic acids (in methyl ester form, DAME) increased as the 1D McReynolds' polarity value of the column phase decreased. Since Te of sesquiterpene hydrocarbons decreased with increased polarity, the very polar SLB-IL111 1D phase leads to excessive peak broadening in the 2D apolar phase due to increased second dimension retention (2tR). The combination of SLB-IL59 with a nonpolar column phase was selected, providing reasonable separation and low Te for sesquiterpenes and DAME, compared to other tested column sets, without excessive 2tR. Identities of DAME were aided by both soft (30eV) electron ionisation (EI) accurate mass TOFMS analysis and supersonic molecular beam ionisation (cold EI) TOFMS, both which providing less fragmentation and increased relative abundance of molecular ions. The inter-relation between EI energies, emission current, signal-to-noise and mass error for the accurate mass measurement of DAME are reported. These approaches can be used as a basis for conducting of GC×GC with soft EI accurate mass measurement of terpenes, particularly for unknown phytochemicals.


Assuntos
Temperatura Baixa , Elétrons , Fabaceae/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extratos Vegetais/análise , Ésteres/análise , Peso Molecular , Sesquiterpenos/análise
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