谷氨酸钠及5′-肌苷酸钠+5′-鸟核酸钠(I+G)添加到食品中的稳定性研究

Study on Stability of Monosodium Glutamate and Disodium Inosine-5'-monophosphate+ Disodium Guanosine-5'-monophosphate (I+G) Added to Food

谷氨酸钠和5′-肌苷酸钠+5′-鸟苷酸钠(I+G)常被添加到食品中来提高鲜味。为了有效利用谷氨酸钠和I+G,将其添加到新鲜萝卜、腌制蔬菜、面粉中,并做热处理实验。谷氨酸钠和I+G含量采用HPLC法测定。结果表明,将谷氨酸钠和I+G添加到新鲜萝卜中,经过85℃和100℃热处理,放置3d,谷氨酸钠保存率分别为76.0%和76.3%,I+G保存率分别为95.6%和95.8%。而先放置3d,再分别85℃和100℃热处理,谷氨酸钠保存率分别为49.0%和41.8%,I+G保存率分别为8.7%和6.9%。将谷氨酸钠和I+G添加到腌制榨菜和腌制雪菜中,经过85℃热处理5min并放置7d,榨菜和雪菜中谷氨酸钠保存率分别为62.5%和67.5%,I+G保存率分别为86.2%和87.2%。而先放置7d,再85℃热处理5min,榨菜和雪菜中谷氨酸钠保存率分别为7.5%和7.5%,I+G保存率分别为38.7%和38.4%。将谷氨酸钠和I+G加到面粉中,180℃高温油炸处理3min,谷氨酸钠保存率为18.8%,I+G保存率为7.9%。在新鲜切割蔬菜和腌制蔬菜中添加谷氨酸钠和I+G,需进行85℃以上热处理,油炸食品的油炸温度不宜过高。

Abstract Monosodium glutamate （MSG）, disodium inosine-5＇-monophosphate ＋ disodium Guanosine-5＇-monophos- phate （I＋G） were always added to food to enhance flavor. To make effective use of added monosodium glutamate and I＋ G,they were added to flesh radish, pickled vegetables and flour to measure its content change by HPLC after heat treat- ment. The resuLts showed that when monosodium glutamate and I＋G were added to fresh radish with 85℃ and 100℃ heat treatment, monosodium glutamate reserved 76.0% and 76.5%, I＋G reserved 95.6% and 95.8% after 3 days. Howev- er, monosodium glutamate reserved 49.0% and 41.8%, I＋G reserved 8.7% and 6.9% with 85℃ and 100 ℃ heat treat- ment after 3 days. When monosodium glutamate and I＋G were added to pickled tuber mustard and pickled yukina with 85 ℃ heat treatment for 5 min, monosodium glutamate reserved 62.5% and 67.5%, I＋G reserved 86.2% and 87.2% after 7 days. However, monosodium glutamate reserved 7.5% and 7.5%, I＋G reserved 38.7% and 38.4% with 85℃ heat treatment for 5 min after 7 days. When monosodium glutamate and I＋G were added to flour with 180℃ high-temperature treatment for 3 min, monosodium glutamate reserved 18.8%, I＋G reserved 7.9%. Thus, when monosodium glutamate and I＋G were added, flesh cut vegetables and pickled vegetables should be heated before hand for at least 85 ℃; the deep- fried temperature should not be too high for deepfried food.