Diet Pepsi Recipe

Name: The Pelican Post Bar & Grilles Diet Pepsi Recipe
Cook time: 10 min
Total time: 10 min
Yield: 1 servings
Ingredients: 12 fl oz Carbonated water (chilled); 1 fl oz Diet cola syrup or cola-flavored concentrate; 1 tsp Caramel color (liquid); 1 tsp Phosphoric acid solution (food-grade, diluted); 50 mg Caffeine solution (food-grade, diluted) or instant caffeine; 100 mg Aspartame (or preferred zero-calorie sweetener blend); 50 mg Acesulfame K (if using a blend); 0.25 tsp Natural cola flavoring (vanilla, citrus, spice blend); 1 tsp Citric acid (for brightening); 6 pieces Ice cubes; 1 piece Lemon or lime wedge

Inspired by The Pelican Post Bar & Grille

Time10m

Serves1

Make Diet Pepsi Recipe in just 10m. Get the full recipe with step-by-step instructions at pekinthechef.com.

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Ingredients

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Syrup base

12 fl oz Carbonated water (chilled)

1 fl oz Diet cola syrup or cola-flavored concentrate

1 tsp Caramel color (liquid)

1 tsp Phosphoric acid solution (food-grade, diluted)

0 oz (50 mg) Caffeine solution (food-grade, diluted) or instant caffeine

Sweeteners & flavor modifiers

0 oz (100 mg) Aspartame (or preferred zero-calorie sweetener blend)

0 oz (50 mg) Acesulfame K (if using a blend)

1/4 tsp Natural cola flavoring (vanilla, citrus, spice blend)

1 tsp Citric acid (for brightening)

Garnish (optional)

6 pieces Ice cubes

1 piece Lemon or lime wedge

Method

Prepare chilled glass and ice

Chill and ice

Chill a tall glass in the refrigerator or freezer for 5–10 minutes. Add 6 ice cubes to the glass just before pouring to keep the beverage cold without over-dilution.

Mix sweeteners and flavor modifiers

In a small bowl or measuring cup, combine the aspartame and acesulfame K (if using). Add the citric acid, natural cola flavoring (vanilla/citrus/spice blend), caramel color, and phosphoric acid solution. Stir thoroughly until the powdered sweeteners and acids are fully dissolved into a smooth syrup-like concentrate. If using instant caffeine, dissolve it here as well. Taste a small pinch to confirm balance: it should be noticeably sweet with a bright acidic note and cola aromatics.

Assemble Diet Pepsi

Measure 1 fl oz of the prepared syrup concentrate (sweetener + flavor modifiers) and pour it into the chilled, ice-filled glass.

Carefully pour 12 fl oz of chilled carbonated water over the syrup concentrate. Pour slowly to preserve carbonation and to encourage gentle mixing.

Gently stir once with a long spoon or straw — 3 to 5 slow rotations — to evenly distribute the concentrate without flattening the soda.

Add the caffeine solution (50 mg) by stirring it into the glass so it dissolves completely. If you included caffeine earlier in the syrup mix, skip this step.

Taste and adjust: if it needs more brightness, add a very small pinch (1/8 tsp) of citric acid or a squeeze of the lemon/lime wedge. If it needs more sweetness, dissolve an extra 25–50 mg of sweetener and stir gently.

Garnish and serve

Garnish the rim with the lemon or lime wedge if desired. Serve immediately while fizzy and cold.