Dados do Trabalho

Título

TECHNO-FUNCTIONAL PROPERTIES OF PIASSAVA PROTEIN FRACTION: POTENTIAL FOOD APPLICATIONS

Introdução

The techno-functional properties of proteins influence sensory characteristics - such as texture, taste and appearance - and act to stabilize and preserve food systems. Defatted piassava (Attalea funifera Martius) flour contains 14% protein. In this study, the technological and functional properties of whole flour, protein concentrate and the major fraction (glutelin) of piassava seed flour were determined.

Material e Métodos

The whole flour was obtained using previously established processes. The protein concentrate was obtained by solubilizing and precipitating the protein fraction. Glutelin was obtained by fractionating the total protein isolate. The averages of the results were evaluated by analysis of variance (ANOVA) and compared using the Tukey test (p ≤ 0.05).

Resultados e Discussão

Next, they were evaluated for Water (WHC) and Oil (OHC) Holding Capacity; Emulsifying Activity (EAI) and Stability Index (ESI); Foaming Capacity (FC) and Stability (FS) for the pH's 3.2, 5.3 and
8.0. Glutelin showed higher levels of WHC (7.55±0.37 g/g) and OHC (4.46±0.01 g/g) when compared to flour (2.02±0.04 g/g and 2.37±0.07 g/g, respectively) and protein concentrate (2.08±0.17 g/g and 1.86±0.35 g/g, respectively). These properties are essential in the production of viscous foods and in the manufacture of sausages. The protein concentrate and glutelin obtained the highest levels of activity (47.95±0.86 m2/g and 40.88±0.20 m2/g, respectively) and emulsion stability (41.9±2.9 min. and 31±2.8 min., respectively) at pH 8.0. This can be explained by the fact that there is greater exposure of the hydrophobic groups of the proteins to charged ions at pH's > 7.0. The low stability of the emulsion, especially near pI, can be attributed to the increase in interactions between the emulsified droplets, due to the reduction in the net charge on the proteins. FC was observed at pH 8.0 of the flour (195.6±2.9%) and concentrate (403.3±3.3%), but low FS (53±5.6% in up to 10 minutes; and 30.1±5.7% in up to 60 minutes, respectively).

Conclusão

However, the results found in this study indicate the potential for applying the techno-functional properties of piassava flour, protein isolate and glutelin fraction in food products.