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A presente pesquisa teve por objetivo a obtenção e caracterização de produtos derivados do caju. Para tanto, produtos da castanha-de-cajueiro comum e do pedúnculo de caju do clone CCP76 foram processados e submetidos a análises físicas e químicas. Mediante prensagem da amêndoa de castanha-de-caju obtevese a torta parcialmente desengordurada (36,41% de proteínas, 26,57% de lipídios totais e 7,86% de fibra digestiva total) e o óleo (82,74% de ácidos graxos insaturados, predominando o ácido oléico -60,30% e o linoléico -21,53%). Do pseudofruto do caju foi obtido o suco clarificado e concentrado a vácuo (teor de ácido ascórbico de 966,13 mg/100 g de suco) e a fibra de caju (61,21% de fibra digestiva total). Concluiu-se que os produtos originários do caju apresentam elevado potencial para a elaboração de diferentes produtos alimentícios em virtude da diversidade e riqueza na composição química da castanha e do seu pseudofruto.

Nibs of raw cocoa (N) were roasted (R) at 150 °C for 38 min. Some samples were autoclaved at 121 °C for 15 min (A) and roasted (AR) at 150 °C for 38 min. The samples were then analysed for moisture content, water activity (aw), reducing sugar and amino group (α‐N) levels and, absorption at 275 nm (A275) for a trichloro acetic acid (TCA) extract and at 280 nm (A280) for the distillate. Tri‐ and tetramethylpyrazines were quantified by solid phase micro extraction‐gas chromatography (SPME‐GC). There was a reduction in the levels of α‐N, in the order N > A > R > AR. The same sequence was observed for reducing sugars. The tetramethylpyrazine had an Areapyrazine/Areainternal standard of N < R < A < AR and for trimethylpyrazine the order was N < A < R < AR. After autoclaving, the Atetra/Atri decreased from 31.30 (N) to 11.06 (A). With roasting, this ratio was 2.18 (R) and 2.58 (AR). Autoclaving nibs before roasting significantly influenced the levels of compounds which contribute to cocoa flavour formation and increased the concentration of tri‐ and tetramethylpyrazines in the headspace of cocoa samples. Autoclaving prior to roasting also affected the sensory properties of the samples.

The development of an analytical method using 1H nuclear magnetic resonance (1H NMR) spectrometry to monitor cupuassu (Theobroma grandiflorum Spreng) bean fermentation, drying, and roasting processes is reported. The analysis of organic acids and alcohols of crude water extracts of cupuassu ground kernels were monitored by HPLC and 1H NMR spectroscopy. The residual protein signals caused deleterious effects on acid and alcohol quantifications. Therefore, the analytical procedures were optimized by sample cleanup and water suppression pulse sequences in order to obtain compatible data using HPLC and 1H NMR. The quantification of lactic acid, acetic acid, and 2,3-butanediol by NMR is 5- to 10-fold faster than by HPLC, with the advantage of providing the identification of several chemical species in a single experiment. Application of these analytical conditions to some cupuassu samples revealed that this methodology can be applied to the quality profiles of fermentation and roasting processes.

Um procedimento de Microextração em Fase Sólida em Headspace (HS-SPME) para isolamento e determinação de alquilpirazinas em liquor de cacau, usando Cromatografia Gasosa com Detecção por Ionização em Chama (GC-FID) é apresentado aqui. As condições operacionais de HS-SPME foram otimizadas usando extrações de amostras fortificadas com quantidades conhecidas de alquilpirazinas tipicamente encontradas em derivados de cacau. A eficiência máxima de extração foi obtida com fibras de SPME recobertas com 65 µm de Carbowax/divinilbenzeno. Em adição, os melhores resultados foram obtidos usando 60 ºC como temperatura de extração, 15 min como tempo de equilíbrio amostra/headspace e 45 min como tempo de extração. Observou-se também que o uso de solução aquosa saturada de NaCl para suspender as amostras durante as extrações resultou em um incremento significativo nas áreas dos picos. Este procedimento se mostrou efetivo para a determinação das razões pirazínicas (quocientes entre as áreas dos picos de alquilpirazinas), que são úteis como parâmetros de qualidade para liquor de cacau.A Headspace Solid Phase Microextraction (HS-SPME) procedure for isolation and determination of alkylpyrazines in cocoa liquor, using Gas Chromatography with Flame Ionization Detection (GC-FID) for the separation and detection of the analytes, is presented here. The HS-SPME operational conditions were optimized using extractions of samples spiked with known amounts of alkylpyrazines typically found on cocoa products. The maximum extraction efficiency was obtained using SPME fibers coated with 65 µm Carbowax/divinylbenzene. Additionally, the best results were achieved with extraction temperature of 60 ºC, 15 min of sample/headspace equilibration time and 45 min extraction time. It was also observed that suspending the samples in saturated aqueous NaCl solution during extractions resulted in a significant increment on the peak areas. This procedure was found to be effective to determine the so-called pyrazinic ratios (quotient between peak areas of alkylpyrazines), which are useful as quality parameters for cocoa liquor.Keywords: cocoa liquor, alkylpyrazines, aroma, Maillard reaction products, SPME IntroductionThe processing of cocoa seeds (Theobroma cacao, L.) 1 comprises their drying, fermentation of sugars contained in the pulp covering the seeds, roasting, separation and grounding of the roasted nibs. The resulting fatty solid product (known as cocoa liquor) is the base raw material for chocolate industry. The most significant flavor-impact substances on cocoa derivatives are N-and O-containing heterocyclic compounds generated during the roasting, which are products of the complex sequence of heatinduced chemical processes collectively known as Maillard reactions. 2 The substrates for the Maillard reactions are reducing sugars, small peptides, aminoacids and / or triglycerides contained in the raw, unroasted material. For cocoa, in terms of contribution to their sensorial characteristics (and, in consequence, to their commercial value), the most im...