Drinking plenty of water and increasing vitamin C intake before singing is optimal for voice strength. Citrus-based liquids and infused waters can help maintain the vocal chords before a performance.
Ensuring proper hydration and Vitamin C levels prior to a performance helps keep a voice in peak condition, according to vocalist.org. Infused water is perfect for this.
A common misconception is that hot tea with lemon is a good drink to keep vocal chords healthy. Vocalist.org states that coffee, tea and related beverages will only cause dehydration and make a voice worse, while hot infused water with citrus helps prior to a performance. Just remember to avoid black and green teas, and get plenty of rest.