DIY Maurten 320 Recipe: The $0.40 Version of a $4 Race Drink

Maurten 320 has built a loyal following among marathoners and triathletes, including the entire sub-two-hour marathon project. The product is genuinely well-formulated. It is also $3.50 to $4.00 per 500ml serving, which adds up fast if you train more than a few hours per week.

The good news: the carbohydrate formula behind Maurten 320 is not secret. It is maltodextrin plus fructose, sodium citrate, and a hydrogel matrix that forms in your stomach. The carb profile, the electrolyte dose, and the dual-transporter absorption mechanism are all fully replicable with bulk ingredients at about $0.40 per bottle.

This post covers what is actually in Maurten 320, how the hydrogel works and what you lose without it, a complete DIY maurten 320 recipe, and a cost breakdown that shows the math on the savings.

What is actually in Maurten 320

Maurten 320 contains 80 grams of carbohydrate per 500ml serving, delivered as a blend of maltodextrin and fructose at approximately a 0.8:1 ratio (maltodextrin to fructose), plus roughly 500mg of sodium in the form of sodium alginate and sodium citrate. The hydrogel matrix, formed from sodium alginate and pectin, is the proprietary element. The carbohydrate and electrolyte profile is not proprietary and is replicable at home.

Here is a look at the full Maurten 320 ingredient panel broken down by function:

Ingredient	Role	Amount per 500ml
Maltodextrin	Primary carb source (glucose polymer, low osmolarity)	~45g
Fructose	Secondary carb source (GLUT5 transporter)	~35g
Sodium alginate	Hydrogel-forming agent, sodium source	Structural
Pectin	Hydrogel-forming co-agent	Structural
Sodium citrate	Electrolyte buffer	Majority of ~500mg sodium
Total carbohydrate	Both transporters saturated	80g
Total sodium	Sweat replacement	~500mg
Calories	Caloric density	320 kcal

The "320" in the product name refers to the calorie count: 80 grams of carbohydrate times 4 kcal/g equals 320 kcal.

The carb ratio: 0.8:1 or 1:0.8?

Maurten describes their blend as a 0.8:1 ratio of maltodextrin to fructose, which means more fructose relative to maltodextrin than the standard 2:1 sports science benchmark. This is a deliberate choice. The higher fructose fraction more fully loads the GLUT5 transporter and allows absorption at 80 to 90 grams per hour rather than the ~60g/hour ceiling you hit with single-transporter products.

In practice, a ratio anywhere from 1:0.8 to 1:1 works well at this carb load. The exact ratio matters less than ensuring both transporters have substrate.

How the Maurten hydrogel works

When Maurten's hydrogel drink enters the stomach, the alginate and pectin react with stomach acid to form a soft gel capsule around the carbohydrate solution. This gel temporarily lowers the effective osmolarity of the contents in your gut, which speeds gastric emptying and reduces GI stress. The gel dissolves quickly in the small intestine, releasing carbohydrates for absorption. The practical effect is a drink that behaves more like water in the stomach than like a concentrated sugar solution.

Osmolarity is the key variable. Here is why it matters:

• A hypertonic drink (high osmolarity, above ~300 mOsm/kg) pulls water from your bloodstream into the gut to dilute it, which slows gastric emptying and can cause bloating.
• A hypotonic or isotonic drink (below ~300 mOsm/kg) empties faster and delivers carbohydrates to the small intestine more quickly.
• At 80g carbohydrate in 500ml without the hydrogel, a maltodextrin-fructose blend is mildly hypertonic (roughly 350 to 450 mOsm/kg depending on the ratio).
• With the hydrogel, the effective osmolarity presented to the stomach lining is much lower, because the carbohydrate is temporarily encapsulated rather than free in solution.

Maurten's published research shows the hydrogel reduces GI symptoms compared to a carbohydrate-matched control in laboratory conditions. Whether this translates to meaningful performance differences in real racing conditions is more contested in the literature, but the mechanism is real.

What you lose without the hydrogel

A maurten copycat recipe without alginate and pectin will have a slightly higher osmolarity than the original. At 80g carbs in 500ml, you are looking at roughly:

Component	Osmolarity contribution (mOsm/kg per 500ml)
45g maltodextrin	~90
35g fructose	~389
0.5g sodium citrate	~3
Estimated total	~480 mOsm/kg

That is hypertonic territory. The honest mitigation is more water: at 750ml total volume, osmolarity drops to roughly 320 mOsm/kg, which is near isotonic and well-tolerated by most athletes. At 1,000ml (a standard large bidon), it is hypotonic and behaves similarly to what the hydrogel achieves in a 500ml bottle.

The practical recommendation: use 750ml of water per 80g carb serving instead of 500ml if you do not want to approximate the hydrogel effect with food-grade additives. You lose some of the convenience of a concentrated bottle, but the carb and electrolyte profile is identical and the GI load is comparable.

For athletes who want to get closer to the hydrogel effect, food-grade sodium alginate is available as a culinary ingredient (used in molecular gastronomy). A small addition (0.5 to 1g per bottle) can produce a mild gel effect in the stomach. This is advanced territory and not necessary for most athletes, so the base recipe below focuses on the carb and electrolyte formula.

DIY Maurten 320 recipe (per 500ml bottle, 80g carbs)

This recipe targets the same carb load, electrolyte dose, and dual-transporter mechanism as Maurten 320. It uses sodium citrate as the sole sodium source rather than sodium alginate, which is the key ingredient swap.

Ingredients

Ingredient	Amount	Notes
Maltodextrin (DE 10-20)	44g	Fine powder dissolves best
Fructose	36g	Granulated or fine crystal
Sodium citrate	0.85g	Smooth, buffering electrolyte source
Water	500ml (or 750ml)	750ml recommended for lower osmolarity
Optional: citric acid	Pinch (~0.1g)	Tartness without bitterness
Optional: food flavoring	A few drops	Lemon or orange complements well

Sodium note

0.85g of sodium citrate delivers approximately 500mg of elemental sodium, matching the Maurten 320 electrolyte profile. If you are a heavy sweater or racing in heat, you may want to increase this to 1.0 to 1.3g sodium citrate (600 to 770mg sodium). Use the DIY sports drink calculator to dial in your exact dose based on your sweat rate and duration.

Method

1. Add the maltodextrin and fructose to your bottle first. Maltodextrin can clump if liquid is added to the dry powder in a narrow bottle, so adding both dry ingredients first and then the water works better.
2. Add the sodium citrate and citric acid if using.
3. Add about 100ml of warm water and shake or stir until the powders are fully dissolved. The maltodextrin dissolves more readily in slightly warm water.
4. Top up with cold water to 500ml (or 750ml for lower osmolarity).
5. Shake well. The drink should be clear to slightly cloudy.

Prepared bottles can be refrigerated for up to 24 hours without degradation.

Nutritional profile vs Maurten 320

Metric	Maurten 320	DIY version
Total carbohydrate	80g	80g
Maltodextrin	~44g	44g
Fructose	~36g	36g
Carb ratio (malto:fructose)	~1:0.8	1:0.82
Sodium	~500mg	~500mg (adjustable)
Hydrogel	Yes (alginate + pectin)	No
Estimated osmolarity (500ml)	~150-200 mOsm/kg (gelled)	~480 mOsm/kg
Estimated osmolarity (750ml)	N/A	~320 mOsm/kg
Calories	320 kcal	320 kcal
Potassium	Trace	0 (add NoSalt if desired)

The only meaningful difference is the hydrogel and the resulting osmolarity in a 500ml bottle. At 750ml, the osmolarity difference is small and well within the range most trained athletes tolerate without GI issues.

Cost breakdown: Maurten 320 vs DIY

This is where the math gets stark. Maurten 320 retails for $3.50 to $4.00 per serving at most US retailers. The same 80 grams of carbohydrate with the same electrolyte profile costs about $0.40 when made from bulk ingredients.

Per-serving cost

Component	Maurten 320	DIY (bulk pricing)
Maltodextrin (44g)	Included in price	$0.18
Fructose (36g)	Included in price	$0.14
Sodium citrate (0.85g)	Included in price	$0.02
Packaging/flavor/etc.	Included	$0.01 to $0.05
Total per serving	$3.50 to $4.00	~$0.35 to $0.45

Bulk ingredient prices (as of mid-2026, Amazon):

Ingredient	Bulk package	Price	Cost per gram
Maltodextrin	5 lb (~2.27 kg)	~$14 to $18	$0.006 to $0.008/g
Fructose	5 lb (~2.27 kg)	~$16 to $20	$0.007 to $0.009/g
Sodium citrate	1 lb (~454g)	~$10 to $14	$0.022 to $0.031/g

A 5 lb bag of maltodextrin plus a 5 lb bag of fructose plus a 1 lb bag of sodium citrate gives you roughly 140 to 150 bottles at the above recipe quantities. Total outlay: approximately $40 to $52. Per bottle: $0.28 to $0.37, not counting water.

Annual savings at training volume

Training volume	Maurten cost (one bottle per session)	DIY cost	Annual savings
4 hrs/week (2 long sessions)	~$416/year	~$42/year	~$374/year
8 hrs/week (4 sessions)	~$832/year	~$84/year	~$748/year
12 hrs/week (6 sessions, typical age-group triathlete)	~$1,248/year	~$126/year	~$1,122/year
20 hrs/week (high-volume, Ironman or ultra build)	~$2,080/year	~$210/year	~$1,870/year

These numbers assume one 500ml bottle per session and do not account for races where athletes use two to four bottles. High-volume athletes doing Ironman race prep or ultra-marathon training who rely on Maurten for both training and racing can easily spend $4,000 to $6,000 per year on the commercial product. The DIY version cuts that to $400 to $600.

Variations on the base recipe

Higher carb version (90g/hr for trained athletes)

Some athletes, particularly those with high carbohydrate oxidation capacity developed through gut training, can absorb 90 to 120 grams per hour. To scale the recipe:

Ingredient	Amount for 90g carbs
Maltodextrin	50g
Fructose	40g
Sodium citrate	0.85 to 1.0g
Water	750 to 850ml

This approaches Maurten's Drink Mix 160 category (two servings of 320 per hour). Start at 80g/hr and work up over several training sessions to allow gut adaptation.

Lower carb version (40-60g/hr for shorter efforts)

For efforts under 90 minutes or athletes who prefer a lighter concentration:

Ingredient	Amount for 60g carbs
Maltodextrin	33g
Fructose	27g
Sodium citrate	0.7g
Water	500ml

At 60g per hour in 500ml, osmolarity is manageable (~360 mOsm/kg) and many athletes find this concentration easier to drink without diluting further.

Adding potassium and magnesium

The base DIY Maurten copycat recipe matches Maurten 320's electrolyte label, which lists sodium only in meaningful quantities. If you want a more complete electrolyte profile for long efforts in heat:

Addition	Ingredient	Amount per bottle	Electrolyte added
Potassium	Potassium citrate (NoSalt is potassium chloride)	0.3g potassium chloride	~150mg potassium
Magnesium	Magnesium glycinate powder	0.25g	~25mg magnesium

These are optional additions for ultra-distance athletes or hot-weather racing. For standard marathon or half-Ironman efforts, sodium is the primary electrolyte loss and the base recipe is sufficient.

The DIY sports drink calculator lets you adjust all of these variables, including weight, sweat rate, duration, and electrolyte targets, and outputs a complete per-bottle recipe.

Gut training with the DIY recipe

One reason elite athletes can absorb 80 to 120 grams of carbohydrate per hour is that they have trained their gut to handle it. The digestive system responds to regular high-carb intake during training by upregulating SGLT1 and GLUT5 transporter density. This is trainable over 4 to 8 weeks of consistent high-carb long sessions.

The protocol:

• Week 1 to 2: 60g carbs/hr during long sessions (2 x 30g/hr bottles)
• Week 3 to 4: 70g carbs/hr (practice with the base 80g recipe diluted to 750ml)
• Week 5 to 6: 80g carbs/hr at standard 500ml concentration
• Week 7 to 8: 90g+ carbs/hr if targeting elite absorption rates

The DIY recipe is actually better than Maurten for gut training because you can control the concentration exactly. You are not locked into the fixed 320-calorie packet format.

Shelf life and preparation tips

• Dry premix: measure and combine the dry ingredients (maltodextrin, fructose, sodium citrate) in advance and store in small zip bags or containers. Each bag contains one serving. Preparation at the trailhead or race morning is then just adding water.
• Dissolving: maltodextrin can be sticky at high concentrations. A small whisk, a shaker bottle with a mixing ball, or 20 to 30 seconds of vigorous shaking in a 1-liter bottle solves this.
• Prepared bottle refrigerated: 24 to 48 hours without quality loss. Do not leave prepared bottles at room temperature for more than a few hours.
• Color and clarity: the solution will be clear to slightly cloudy depending on the maltodextrin source. Fructose is transparent. Neither ingredient produces a colored drink, so add food coloring or flavoring if you want visual confirmation of which bottle is which during a race.

Frequently asked questions

Is DIY Maurten 320 safe to race with?

Yes. The ingredients (maltodextrin, fructose, sodium citrate) are food-grade and used in dozens of commercial sports nutrition products. Sodium citrate is also widely used as a food preservative (E331). The DIY recipe uses the same functional ingredients as Maurten 320, minus the hydrogel agents. As with any race nutrition change, test during training before using on race day.

What maltodextrin should I buy?

Look for food-grade maltodextrin with a dextrose equivalent (DE) of 10 to 20. Higher DE means shorter chain length and sweeter taste. DE 18 to 20 is the most common for sports nutrition DIY. Brands commonly available on Amazon include NOW Foods Carbo Gain and BulkSupplements maltodextrin. Avoid industrial maltodextrin or tapioca maltodextrin marketed for baking (different texture and solubility).

Why sodium citrate instead of regular table salt?

Sodium citrate is tribasic sodium citrate, a salt of citric acid. It delivers the same elemental sodium as table salt (NaCl) but with three differences: it is smoother-tasting at high concentrations (no harsh salty bite), it acts as a pH buffer in the stomach (mildly alkaline, which may buffer lactic acid slightly), and it mixes cleanly without affecting the carbohydrate taste. At the doses used in sports drinks (0.5 to 1g per bottle), the difference from table salt is subtle, but sodium citrate is the better choice for palatability in a high-carb, high-volume drink. Table salt at equivalent sodium doses makes the drink noticeably saltier-tasting.

Does the DIY version cause more GI issues than Maurten?

It might, particularly at 500ml concentration in athletes who are sensitive to high-osmolarity drinks. The hydrogel in Maurten reduces effective osmolarity in the stomach, which is the primary mechanism behind its GI-tolerability claim. At 750ml water per 80g carbs, osmolarity comes down to near-isotonic levels and most athletes tolerate this without issues. If you have a sensitive gut and want to match Maurten more closely, using a larger water volume is the practical solution, not hydrogel additives.

Can I add the hydrogel ingredients to make a true maurten copycat recipe?

Food-grade sodium alginate is available from culinary suppliers (used for spherification in molecular gastronomy). Adding 0.5 to 1g of sodium alginate per bottle will produce some gel formation in the acidic stomach environment. Pectin (available as canning pectin, e.g., Sure-Jell) can be added at 0.5g for the co-agent effect. The gel formed will not be identical to Maurten's proprietary formula, but it approximates the mechanism. This adds minor complexity and cost (roughly $0.05 to $0.10 per bottle) and is worth experimenting with if you specifically want the hydrogel effect for racing rather than training.

How does this compare to SIS Beta Fuel and other high-carb drinks?

Product	Carbs/serving	Maltodextrin:Fructose	Sodium	Price/serving	Hydrogel
Maurten Drink Mix 320	80g	~1:0.8	~500mg	$3.50 to $4.00	Yes
SIS Beta Fuel	80g	1:0.8	310mg	$3.00 to $3.50	No
Precision Fuel 90	90g	2:1	300mg	$2.50 to $3.00	No
Tailwind Endurance	50g	glucose only	303mg	$1.75 to $2.25	No
DIY (this recipe)	80g	1:0.82	500mg	~$0.40	No (optional)

SIS Beta Fuel and Precision Fuel 90 use the same dual-transporter approach without the hydrogel and at lower sodium. The DIY version matches Maurten's carb and sodium profile more closely than either commercial alternative.

How long does a batch of dry premix last?

Stored in an airtight container in a cool, dry location, a dry premix of maltodextrin and fructose will last 12 to 18 months without quality loss. Sodium citrate is shelf-stable for 2 to 3 years. Pre-measured single-serving bags (one per training session) make race-morning preparation as fast as reaching for a Maurten sachet.

Put the calculator to work

The recipe above is a starting point. Your actual needs depend on your sweat rate, training duration, ambient temperature, and whether you are targeting gut training or race-day performance. The DIY sports drink calculator calculates your per-bottle recipe based on those variables and outputs exact gram quantities for maltodextrin, fructose, and sodium. It also shows you the osmolarity of your mix at different water volumes, which is the key variable for GI tolerance without the hydrogel.

If you train 8 or more hours per week and rely on a high-carb fueling strategy, the cost savings over a season are substantial. The DIY maurten 320 approach is not a compromise on performance. It is the same dual-transporter formula, the same electrolyte profile, and the same caloric density, built from the same category of ingredients, for about ten cents on the dollar.