Abstract: In this paper bacteriostatic chart of Chufa functional compound—BQ was studied by using filter paper technique. Its preserving effect was studied by mensurating bacterial count in water chestnut cake. The results showed BQ had obvious bacteriostatic effect and the effect on bacteria is superior to mildew and yeast. In water chestnut cake, BQ preserving effect can be clearly watch out when its addition level is more than 0.1%. 0.5% BQ has the same preserving ability with 0.1% potassium sorbate that can prolong shelf life to 7days. It also can moderate the problem relating to the quality of water chestnut cake such as corrupt spot, aerogenesis and bleeding water. And Its has good dose-effect relationship between Adding level and quality.

Key words: Chufa functional compound, water chestnut cake, bacteriostatic effect, preserving effect