Stone Grinding vs Blade Grinding: Which Peanut Butter Should You Eat?
The peanut butter in most Indian supermarkets was made by a high-speed steel blade spinning at thousands of RPM. The jar looks the same. The label says peanut butter. But what happened to the peanut inside is very different from stone-ground. Here is an honest comparison.
How Blade Grinding Works
Commercial blade grinders rotate metal blades at speeds between 3,000 and 10,000 RPM. This generates enormous friction. Temperatures in commercial grinding operations routinely exceed 70°C to 80°C during continuous production. The process is fast, cheap to run and easy to scale. For factories producing tonnes per day, it is the only economically viable option.
How Stone Grinding Works
Stone grinding uses two horizontal stone surfaces rotating slowly against each other. Friction is minimal and distributed across the entire surface. At 60 RPM, the process takes significantly longer per batch. The temperature barely rises. The peanut is slowly pressed and smeared into a paste rather than shredded.
The Nutritional Difference
Heat above 50°C degrades vitamin E, accelerates fat oxidation and destroys heat-sensitive enzymes. Stone grinding below 45°C preserves all of these. The natural oils in peanuts, primarily oleic acid and linoleic acid, are released slowly and remain chemically stable. In blade-ground products, some of these oils begin to oxidise during processing, reducing nutritional quality before the jar is even opened.
What Research Shows
A clinical meta-analysis published in Frontiers in Nutrition examined cardiovascular risk factors in peanut and peanut butter consumers. The study found that oleic acid content, best preserved through low-heat processing, was significantly linked to improved cholesterol ratios. High-temperature processing that degrades oleic acid directly undermines the cardiovascular benefit peanuts naturally provide.
Frontiers in Nutrition (2022)
Peanut Consumption and Cardiovascular Risk Factors: RCT and Meta-Analysis
Nut Tribe uses a traditional Jhodpuri pink stone chakki at 60 RPM and below 45°C. No blades. No shortcuts.