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RESUMO -O experimento foi conduzido com o objetivo de obter informações sobre a influência do estádio de desenvolvimento do fruto (época de coleta) e do tipo de congelamento sobre os componentes nutricionais e de textura da polpa de pequi (Caryocar brasiliense Camb.). Os frutos foram coletados na árvore, antes da queda natural; no chão, após a queda natural, e após a queda natural, mantidos três dias em condição ambiente. Em cada época de coleta, após a retirada da casca dos frutos, um grupo de putamens foi congelado diretamente em freezer, e outro, congelado em nitrogênio líquido, antes do congelamento em freezer. Após seis meses, foi retirada a polpa dos putamens para a análise dos teores de carotenóides totais, ß -caroteno, licopeno, vitamina A, proteínas e lipídios; teor de celulose, hemicelulose, pectinas total, cálcio ligado à parede celular e total, atividade da pectinametilesterase e poligalacturonase. Os resultados indicaram que os teores de pigmentos, lipídios, proteínas e atividade da PG aumentaram com o avanço do estádio de maturação dos frutos. Por outro lado, houve diminuição no teor da celulose com avanço do estádio de maturação, enquanto os teores de hemicelulose e cálcio não foram influenciados pela idade do fruto. O tipo de congelamento interferiu nos teores de pigmentos, maiores na polpa congelada em nitrogênio líquido, e na atividade da PG, maior na polpa congelada apenas em freezer. Por último, os resultados mostraram que os frutos coletados na árvore são nutricionalmente inferiores aos coletados após a queda natural. Termos adicionais para indexação: época de colheita, carotenóides totais, ß -caroteno, licopeno, vitamina A, proteínas, lipídios, parede celular. MATURITY STAGE OF FRUITS AND FACTORS RELATED TO NUTRITIVE AND TEXTURE CHARACTERS OF PEQUI (Caryocar brasiliense Camb.) PULPABSTRACT -The experiment was carried out with the purpose to obtain information about changes in the constituents responsible for nutritive and texture traits of pequi pulp related with harvest time and types of freezing. Fruits were collected in the tree before natural fall, in the ground after natural fall and in the ground three days after natural fall. In each harvest time, while one batch of the putamens was frozen in liquid nitrogen and afterwards stored in a freezer, another batch was frozen directly in the freezer. After six months the following analyses were performed in the pulp: contents of proteins, total carotenoid, b-carotene, licopene, vitamin A and lipids (nutritive characters); content of cellulose, hemicelluloses, total pectin, total and bound calcium, activity of polygalacturonase (PG) and pectinmethilesterase (PME) of the cell wall. The contents of pigments, lipids, proteins and activity of PG were the highest in the most advanced stages of maturation of fruits. On the other hand the content of cellulose decreased with the advanced stages of maturation whiles the content of hemicelluloses, total and bound calcium were not affected at the stages of maturation of the fruits. The types of freezing...

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In the present work we propose the use of headspace-mass spectrometry (HS-MS) for the characterisation of monovarietal olive oils, an issue of interest when the origin of an oil has to be determined. The HS-MS procedure involves the direct introduction of the sample into a vial, headspace generation and automatic injection of the volatiles into a mass spectrometer. The results were compared with those obtained using more conventional approaches, including chromatographic, spectrophotometric and other types of analysis. Linear Discriminant Analysis (LDA) was applied to the data obtained with both analytical methodologies to achieve the differentiation of the three types of samples. The proposed method is faster and cheaper than those usually employed for edible oil analysis and no sample preparation is required. Additionally, the measuring process is simple and the results obtained from chemometric treatment are 100% correct as regards classification and prediction, making it an appropriate method for routine control.