DIY Skratch Super High-Carb: the glucose-heavy outlier, copied honestly

Skratch built its brand on real-fruit hydration — the original Sport mix is 20g of carbs plus moderate sodium in a cane-sugar-and-dextrose base, designed for all-day rides at moderate intensity, not for 100g/hr race fueling. Super High-Carb is a different animal entirely, a more recent SKU aimed at the same high-carb race market that SiS and Maurten occupy. Surprisingly, Skratch went a different direction than either.

The formula is 92g of glucose-equivalent from cluster dextrin (highly branched cyclic dextrin, or HBCD) plus just 8g of fructose. That's roughly a 12:1 ratio, meaning your SGLT1 glucose transporter does nearly all the absorption work while the fructose transporter (GLUT5) sits mostly idle. That's a deliberate bet on HBCD's unusually low osmolality: a 100g-per-bottle HBCD mix stays drinkable where a 100g maltodextrin mix would feel syrupy. Skratch's thesis is that if you can get the glucose in fast enough through a single transporter, the dual-transporter boost matters less.

DIY has two honest paths. The faithful copy: cluster dextrin (Glico-brand HBCD or another HBCD specialty supplier — none of our preferred brands, Nutricost / NOW Foods / BulkSupplements, currently stocks pure HBCD) plus a small fructose addition at about $1.20 per 100g serving. That's a real savings off the ~$5.24 retail (the 8-serving bag is $42), but HBCD itself is expensive at roughly $50–80/kg, so the cost advantage is narrower than with maltodextrin-based products. The cheaper path: Nutricost maltodextrin plus NOW Foods fructose at matched macros, about 70¢–$1.00 per serving. You lose the low-osmolality mouthfeel that's Super High-Carb's actual selling point, but the sugars going into your blood are close to equivalent.

Where Super High-Carb's 12:1 ratio is honestly limiting: at 100g of carbs per hour, you're leaving absorption capacity on the table compared to a 1:0.8 mix. The research on dual-transporter utilization is clearer than the research on HBCD-alone pathways, and if you're genuinely pushing toward 120g/hr in a hot race, the literature more clearly supports the SiS/Maurten ratio than Skratch's HBCD-heavy one. Super High-Carb is arguably less about maximizing absorption and more about drinking a lot of carbs without GI distress at moderate race efforts.

The clearest use case for Super High-Carb (commercial or DIY) is the rider who wants 80–100g/hr of predominantly-glucose fuel without the thick, cloying feel of an equivalent maltodextrin solution. If that rider has the budget for $5+ servings and likes Skratch's flavor profile, retail is fine. If they want the same low-osmolality drink for a fraction of the price, DIY HBCD gets there. If they're actually racing at the ceiling of human carb absorption, a 1:0.8 mix is probably the better product shape regardless of brand.