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ABSTRACT. High productivity and meantime perishability of in natura eggs, make powdered egg attractive for patisseries and pasta industries. Water reduction in 65%, extends shelf life from 1 to 12 months, preventing also Salmonella. Maximum powdered egg moisture allowed by Brazilian law is 6.0% (w w -1 ). However, its determination by reference technique (oven at 105 º C for 8 hour) is lengthy for processing industry. Therefore, the purpose of this study was to investigate the influence of several spectral pre-processing techniques in the application of near-infrared spectroscopy associated with chemometrics models for determination of moisture content in powdered egg, without the need of sample preparation and destruction, held at 0.5 min. Several pre-treatment techniques were evaluated to ensure spectral data reliability such as: standard normal variation; multiplicative scatter correction; smoothing and detrend. The principal component regression (PCR) and partial least squares (PLS) were evaluated with and without pre-treatment. The best results were observed in NIR/PLS model (49 samples), providing an adequate correlation (r) of 0.96, for cross-validation. Using 21 samples as prediction set, NIR/PLS showed relative error (RE) < 2.0%, compared to primary methods oven and thermobalance, indicating to be suitable for industrial quality control.Keywords: chemometrics, near-infrared spectroscopy (NIRS), thermobalance, oven reference method, calibration model, PLS.Investigação de métodos de pré-processamento em espectros NIR combinados com regressão multivariada para determinação de umidade em ovo em pó industrial RESUMO. A alta produtividade e perecibilidade dos ovos in natura torna o ovo em pó atrativo para o uso em confeitarias e indústrias de massas. A redução em 65% de água estende a vida de prateleira do produto de 1 para 12 meses, prevenindo a Salmonella. Pela legislação brasileira, a umidade máxima permitida para o ovo desidratado é de 6% (m m -1). Entretanto, sua determinação por técnica de referência (estufa a 105ºC por 8h) demanda um tempo muito longo para seu uso em processo. Portanto, este estudo teve como propósito avaliar a viabilidade da aplicação da espectroscopia do infravermelho próximo, associada a modelos quimiométricos na determinação da umidade do ovo em pó, feita em 0,5 min., sem a necessidade do preparo e nem destruição de amostra. Pré-tratamentos foram avaliados com intuito de aumentar a confiabilidade dos dados espectrais do modelo de calibração: variação de padrão normal; correção multiplicativa de sinal; e alisamentos. Regressões por componentes principais (PCR) e por mínimos quadrados parciais (PLS) foram avaliadas, juntamente com os pré-tratamentos. Os melhores resultados foram observados na modelagem PLS (49 espectros), apresentando um coeficiente de correlação (r) de 0,96 para a validação cruzada. O conjunto preditor (21 amostras) mostrou um erro relativo (ER) < 2,0% para o modelo NIR/PLS, comparado à estufa e à termobalança, mostrando-se adequado para o controle de qualidade indu...

Abstract. Isabel grape is the main cultivar used to produce juice in Brazil, which has rusticity and high productivity, but it is deficient in anthocyanins, a pigment responsible for the color. Thus, an alternative is the application of abscisic acid (S-ABA), which is responsible to promote the synthesis of anthocyanins. The aim of this work was to evaluate the phenolic compounds composition in "Isabel" grape juice treated with S-ABA, by HPLC-DAD-ESI-MS/MS technique. The results showed the increasing in total anthocyanin concentration in juices, with S-ABA treatments, as well as the proportion of B-ring tri-substituted anthocyanidins. Regarding total flavonols, differences were only significant in juices obtained in 2012 season. S-ABA treatments did not significantly affect the hydroxycinnamic acid derivatives, flavan-3-ols, resveratrol and antioxidant capacity of juices. Juice from "Isabel" grapes treated with S-ABA provides an enhancement of total anthocyanin concentration, mainly when grapes are treated before or at the onset of véraison.a Corresponding author: isidro.hermosin@uclm.es