复合磷酸盐食品添加剂对鲜切梨保鲜效果的研究

Study on fresh keeping effects of food additives named mixed phosphates on fresh-cut pear

鲜切梨在加工过程中易使酶和酚类物质在有氧气的条件下相互接触发生酶促褐变,从而严重影响梨的颜色、风味和品质;同时,叶绿素在食品加工中可发生脱镁反应,生成暗绿色至绿褐色的脱镁叶绿素,从而影响鲜切梨的色泽。由于使用单组分的保鲜剂,很难在控制褐变的同时护色保绿。因此本实验将三聚磷酸钠(STP)、L-半胱氨酸(L-cys)和氯化钠(NaCl)食品添加剂制成复合添加剂,将其应用到鲜切梨的抗褐变、保鲜中,利用复合添加剂中各组分的协同和互补作用,既能防止鲜切梨的酶促褐变又能解决叶绿素褐变的问题,从而延长鲜切梨的保藏期。结果表明:复合食品添加剂的最优组合为0.20%三聚磷酸钠,0.05%L-半胱氨酸和0.25%氯化钠,此时鲜切梨的抗褐变效果最好,保鲜效果最佳。

The fresh-cut pears occur to the enzyme browning easily if the enzyme and the phenolic compounds touch each other under the condition of oxygen which seriously affect the color,flavor and quality of pear.At the same time,chlorophyll can occur to the takeing-off magnesium reaction in the food processing,generating dark green pheophytin to greenish-brown pheophytin,which affect the colour and lustre of fresh-cut pears.Due to the use of single-component antistaling agent,it is difficult to control the enzyme browning and protect green color.This thesis studied that the compound reagent of the sodium tripolyphosphate（STP）,L-cys and NaCl are compounded and applied to the fresh-cut pears.It can not only prevent effectively the enzyme browning,but also solve the chlorophyll browning problem utilizing the function of cooperating with other component.The results indicated that the best combined ratio of mixed phosphates was 0.2% STP,0.05% L-cys and 0.25% NaCl and the result was the best for fresh-keeping.