Structure and functionality of whey protein concentrate-based products with different water contents

DELFINA M. CASSIANI; DIEGO K. YAMUL; PAULA A. CONFORTI; VANINA PÉREZ; CECILIA E. LUPANO

FOOD AND BIOPROCESS TECHNOLOGY

SPRINGER

Año: 2013 vol. 6 p. 217 - 227

1935-5130

Properties of different heated mixtures of whey protein concentrate, starch, gelatine and sucrose with different water contents were studied. The water activity of samples was determined. The structural properties were analysed by confocal laser scanning microscopy, solubility assays in different extraction solutions, polyacrilamide gel electrophoresis and differential scanning calorimetry. Colour, texture and water-holding capacity of samples were also determined. Results show that it is needed a certain water content to form a structure with solid characteristics in these mixtures. The temperature for starch gelatinization is lower than the temperature for whey proteins denaturation, but when sucrose is present, whey proteins are denatured, before the gelatinization of starch. Sucrose presents the major contribution to the adhesiveness of the samples and to the decrease of their water activity. Also, sucrose decreases the firmness and cohesiveness of the samples. The main component that contributes to the browning of the samples during the heat treatment is whey protein concentrate, whereas starch is the main responsible of the water-holding capacity in these samples. Gelatine, on the other hand, does not affect significantly the microstructure of the mixtures in the proportion used in these assays.