Tendo como objetivo a obtenção de hidrolisados proteicos de farinha de trigo com baixo teor de fenilalanina (Phe), foram preparados, inicialmente, extratos proteicos da farinha de trigo, empregando-se método enzimático pela ação de protease de Bacillus licheniformis. Em seguida, esses extratos foram hidrolisados sob a ação do extrato enzimático bruto (EEB), obtido de casca de abacaxi, e de pancreatina comercial; e alguns parâmetros hidrolíticos foram avaliados, tais como temperatura (30; 35; 40; 50; e 70 °C), tempo (1 hora e 30 minutos; 2 horas e 30 minutos; 3 horas e 30 minutos), e pH de reação (6,0; 7,0; 8,0 e 9,0). Para a remoção de Phe, empregou-se o carvão ativado (CA) e a eficiência deste processo foi avaliada determinando-se o teor de Phe por espectrofotometria derivada segunda, na farinha de trigo, assim como nos hidrolisados após tratamento com CA. Para os três parâmetros estudados, observaram-se efeitos variados sobre a remoção de Phe, sendo que os melhores resultados foram encontrados ao se empregar a associação sucessiva de EEB (E:S 10:100, 1 hora e 30 minutos), com a pancreatina (E:S 4:100, 3 horas e 30 minutos), em pH 7,0 a 50 °C, tendo atingido 66,28% de remoção de Phe, o que corresponde a um teor final de Phe de 522,44 mg.100 g-1 de hidrolisado.

With the aim of obtaining wheat flour hydrolysates with low-phenylalanine (Phe) content, protein extracts were prepared using an enzymatic method through the action of a protease from Bacillus licheniformis. Next, these protein extracts were hydrolyzed by a crude enzymatic extract (CEE) obtained from pineapple peel followed by a commercial enzyme (pancreatin). Some parameters, such as temperature (30, 35, 40, 50 and 70 °C), time (1 hour and 30 minutes, 2 hours and 30 minutes, 3 hours and 30 minutes), and pH of the reaction (6.0, 7.0, 8.0 and 9.0) were evaluated. Activated carbon (AC) was used for removing Phe and the efficiency of this process was evaluated by second derivative spectrophotometry, measuring Phe content in wheat flour as well as in its hydrolysates after AC treatment. Varied effects were observed for the three parameters studied, and the best results were found using successive association of CEE (E: S 10:100, 1 hour and 30 minutes) with pancreatin (E:S 4:100, 3 hour and 30 minutes) pH 7.0, at 50°C having reached a final Phe content of 522.44 mg.100 g-1 of hydrolysate.

An enzymatic method was used for obtaining protein extracts from wheat flour using an alkaline protease. Some parameters were evaluated aiming the optimization of this method: temperature (40-50 ºC); time (2-5 h); physical treatment of the sample (no treatment, ultra-turrax/16,000 rpm/5 min and ultrasound/120 W/10 min); enzyme:substrate ratio (E:S) of 5:100 - 10:100 and concentration of wheat flour (1:3, 1:5 and 1:10 w/v). The results showed that the best condition for protein extraction was that using the sample concentration of 1:3 (w/v), ultra-turrax, E:S of 10:100, at 40 ºC, 2 h, having reached an extraction yield of 88.53%.

O presente trabalho teve como objetivo extrair enzimaticamente as proteínas de uma farinha comercial de arroz. Visando aumentar o Rendimento de Extração Protéica (REP), os seguintes parâmetros foram avaliados: tipo de enzima (protease alcalina e neutra); temperatura (40, 50 e 60 °C); pH (9,5, 10,5 e 11,0); tratamento físico da amostra (sem tratamento, ultra-turrax a 16.000 rpm e ultra-som a 120 W, ambos por 5, 10 e 15 minutos); relação Enzima:Substrato (E:S) de 5:100 e 10:100; e concentração inicial de matéria-prima (1:3, 1:5 e 1:10 p/v). Os teores de proteínas da farinha de arroz e dos resíduos foram determinados para o cálculo do REP. Os resultados mostraram que a melhor condição de extração protéica, que levou ao maior REP, foi a que empregou a concentração inicial de matéria-prima a 1:10 (p/v), sem tratamento físico, com pH 10,5, com a protease alcalina na relação E:S de 10:100, a 50 °C, tendo atingido um REP de 63,4%.

The enzymatic extraction of proteins from a commercial rice flour was studied in this work. In order to increase the Protein Extraction Yield (PEY), the following parameters were evaluated: enzyme type (alkaline and neutral protease); temperature (40, 50 and 60 °C); pH (9.5, 10.5 and 11.0); physical treatment of the sample (no treatment; Ultra-Turrax at 16.000 rpm and ultrasound at 120 W, both for 5, 10 and 15 minutes); enzyme:substrate ratio (E:S) of 5:100 and 10:100 and initial concentration of raw material (1:3, 1:5 and 1:10 w/v). The PEY was calculated using the protein contents of rice flour and the extraction residues. The results showed that the best condition for protein extraction, which gave the highest PEY (63.4%), was that using an initial concentration of raw material of 1:10 (w/v), no physical treatment, pH 10.5, the alkaline protease, an E:S of 10:100, at 50 °C.