How is mono sodium glutamate maintain freshness?

Monosodium glutamate (MSG) is primarily used as a flavor enhancer rather than a preservative, but it can indirectly contribute to the perception of freshness in food. By intensifying umami flavors, MSG can make foods taste more appealing, which may lead to the perception that they are fresher. Additionally, MSG can help mask off-flavors that develop in food as it ages, further enhancing the overall taste experience. However, it does not have preservative properties that inhibit microbial growth or spoilage directly.