Base formula · caffeine-free
Hydrogel Batch Card
Set the liquid and your flask sizes. Everything below re-weighs itself.
0.57 g carbohydrate per ml — the ratio every number here scales from
Flasks
Liquid
Batch volume150ml
Carbohydrate85g
Gel hits3.8×40ml
Coverage
Carb rate
Effort
Greca
Bean
Grounds
g dry
brew ≥ 250 ml
Weight
kg (optional)
250 mg
0target 3–6 mg/kg8 mg/kg
Weigh out
WaterHeated to ~70°C. Just steaming, not boiling.
91ml
MaltodextrinPrimary glucose source
49g
FructoseSecond transporter — what lets you exceed 60 g/hr
40g
Fruit pectin powderGel matrix
2.4g
Sodium alginateEncapsulates on contact with stomach acid
1.2g
Kosher salt≈ 0.6 tsp Diamond Crystal, or 0.4 tsp Morton
1.7g
Lemon concentrateRecommended. Your pectin is high-methoxyl and needs acid to set; water brings none, so this is the firmness.
½tsp
Per flask
Method
- Heat the water to ~70°C. Just steaming, not boiling.
- Dry blend the maltodextrin, fructose, pectin and alginate. Whisk them together bone dry — they clump instantly in liquid and you will never get it out.
- Stir the salt into the hot water while it is still thin — kosher flakes dissolve slowly and will not once the maltodextrin thickens things.
- Blend the dry mix into the hot water. Immersion blender. It looks far too thin at this stage. That is correct.
- Simmer two minutes on low, stirring, to hydrate the pectin and alginate.
- Cool below 50°C, then add the lemon — a few drops at a time. Acid on hot pectin hydrolyzes it and you lose the set.
- Refrigerate two hours before judging texture. It thickens dramatically as it cools. Never judge it hot.
Keeps about a week refrigerated. No preservatives — never leave a filled flask in a hot car.