Effect of Moisture, Sugar and Tertiary Butylhydroquinone on Color, Texture and Microstructure of Peanut Paste

The effect of antioxidant, sugar, moisture and storage time on color, texture and microstructure of peanut paste were determined. The addition of 2 or 5% water resulted in decreased lightness (L*), hue angle (h°) and chroma (C) values, while tertiary butylhydroquinone (TBHQ) and sugar levels had no effect on color. Peanut pastes with added moisture had increased hardness, adhesiveness and chewiness, and lower cohesiveness and springiness compared with treatments with no added moisture. TBHQ was not a significant factor for texture, but hardness increased with the level of added sugar. Scanning electron micrographs and image analysis of light micrographs confirmed the presence of aggregation of protein bodies in 2 and 5% moisture treatments. The addition of sugar or TBHQ produced no measurable changes in microstructural features.