Optimización del grado de hidrólisis de proteínas de queso de cabra por medio de redes neuronales artificiales para mejorar sus propiedades funcionales.

MAURICIO ADARO, HÉCTOR STURNIOLO, LAURA FOLGUERA, SONIA BARBERIS Y JORGE MAGALLANES

Mendoza

Congreso; VII Congreso Argentino de Química Analítica.; 2013

Proteolysis modifies the functional properties of cheese and determines its behaviour as a food additive. A certain protein may be highly nutritive, but it may display inadequate functional properties when it is added to a food system. This work focuses on the study and optimizing of hydrolysis degree of hydrolysates goat cheese proteins by artificial neural network. The effects of different factors (pH, Temperature, Time of hydrolysis, Amount of added buffer and Enzyme : Substrate ratio) on hydrolysis degree, expressed Free Amine Nitrogen (NA) and Total Soluble Nitrogen (NT) of hydrolyzed goat cheese proteins was evaluated. A Plackett Burman Statistical Design of 11 runs (by duplicate) was carried out, and Free Amine Nitrogen (NA) and Total Soluble Nitrogen (NT) were determined by the Kjeldhal and Phenol-hypocloride methods in the free fat supernatants after filtering them through filter paper Whatman Nº 1 (AOAC, 2006; Fawcet and Scott, 1960). In order to enhance the flavouring power of the goat cheese by means of protein hydrolysis, the conditions that maximized NA and NT should be selected, i.e. the highest values of ratio (E:S) (0.22 mg of papain/g of cheese casein), Temperature (80°C), Time of hydrolysis (270 min) and the lowest Amount of added buffer (10 g of buffer/g of protein). pH showed a compromised situation, since maximal NA and NT were obtained at 9 and 5, respectively. After optimization, the release of soluble proteins from goat cheese to the supernatant (NT) and the hydrolysis degree of proteins into the supernatant (NA) were increased until 296 % and 342 %, respectively. These values were experimentally confirmed and compared with those of the original protein isolates.