Jul 09 2026
RestaurantsRed WindowDiet Coke Recipe

Diet Coke Recipe

Inspired by Red Window
Time18m
Serves4

Make Diet Coke Recipe in just 18m. Get the full recipe with step-by-step instructions at pekinthechef.com.

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Ingredients

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Diet Cola Syrup (Concentrate)

To Serve

Method

Prepare Diet Cola Syrup (Concentrate)

  1. 1

    Step 1

    In a clean, food-grade container, measure 120 ml of filtered water and pour it in.

  2. 2

    Step 2

    Add 5 ml caramel color (E150d) to the water and whisk until evenly dispersed.

  3. 3

    Step 3

    Stir in 15 ml of cola flavor concentrate until fully blended.

  4. 4

    Step 4

    Carefully add 0.6 ml of phosphoric acid solution and mix well.

  5. 5

    Step 5

    Sprinkle in 0.5 g citric acid and stir to dissolve.

  6. 6

    Step 6

    If using, add 0.3 ml caffeine solution and stir thoroughly.

  7. 7

    Step 7

    Sweeten with 2 g artificial sweetener (aspartame or sucralose); stir until completely dissolved.

  8. 8

    Step 8

    Let the syrup rest for 5 minutes to meld flavors, then cover or bottle and refrigerate. This quantity yields approximately 200 ml of syrup.

Assemble and Serve

  1. 9

    Step 9

    Chill the carbonated water for 10 minutes if desired.

  2. 10

    Step 10

    To serve, pour 250 ml of carbonated water into a tall glass.

  3. 11

    Step 11

    Add approximately 50 ml of Diet Cola Syrup (Concentrate) per drink. This ratio yields four servings from the batch.

  4. 12

    Step 12

    Stir gently to combine. Adjust sweetness or strength by adding more syrup or water to taste.

  5. 13

    Step 13

    Serve immediately. Optional: add ice and a lemon twist for garnish.

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