Industry Application: Rice-Based Excipient Solves PureNSM’s Sticky Situation

PureNSM (also known as Nutritional Supplement Manufacturers), Chula Vista, CA, is a contract manufacturer of nutritional supplements. It produces more than 900 million capsules per year, usually without using traditional excipients. 

“Since 1993, our clients have asked us to manufacture clean-label products, and I believe it’s a trend that’s here to stay,” said Oskar Thorvaldsson, the company’s founder and chief executive officer. “We can manufacture products using magnesium stearate if desired, but that’s the exception not the rule. In general, our clients don’t want chemicals that the common consumer won’t recognize.” 

The higher cost of making clean label products isn’t usually an issue, said Tino Moreno, PureNSM’s sales manager. “Even though we can quote lower prices if we use magnesium stearate, most of our customers are willing to pay more for clean-label products.” By using a clean-label excipient, the production efficiency gained typically more than offsets any additional ingredient costs. 

The company relies on auger-driven capsule fillers, which handle sticky nootropics and other difficult- to-process formulas better than dosator-style machines by forcing the fill into the capsule. In addition, operators have devised some techniques over the years to make the formulations easier to encapsulate, including using air conditioners and dehumidifiers. “We’re continuously learning,” Thorvaldsson said. “Even now we’re making modifications to our capsule filling machine. Two of our engineers are adding a function to the capsule filler’s lower segments to increase our productivity.” 

Perhaps the biggest improvement, however, stems from using natural excipients supplied by Ribus, a St. Louis, MO, manufacturer of rice-based ingredients. PureNSM began using the ingredients 4 years ago. “Now, about 80 percent of our products are made with a Ribus excipient,” Thorvaldsson said. 

It began with Nu-Flow, a natural and certified organic excipient that acts as a flow aid and anti-caking agent. It’s made from sterilized rice hulls that are ground to a fine powder, enabling the naturally occurring silica in the hulls to do the job of traditional additives. “Nu-Flow is great for encapsulating non-free flowing powders,” Moreno said, although some tinkering was required at first. “Getting the right Nu-Flow excipient ratio was tricky,” Thorvaldsson said, “but we had a lot of help from Ribus, which sped the process along.” 

No Magnesium Stearate Required 

In September 2016, Ribus launched Nu-Mag, a blend of rice extract, rice hulls, gum arabic, and sunflower oil that can replace magnesium stearate. According to ejection-force tests performed by the Natoli Institute at Long Island University, Nu-Mag used at 1 percent performed as well as magnesium stearate used at 1 percent, providing the same level of lubrication. 

Products manufactured with magnesium stearate are considered “made with” and cannot be certified organic. Nu-Mag, however, is a certified organic alternative to magnesium stearate that allows nutraceutical manufacturers — especially those hoping to expand into the organic market —to produce organic tablets with a lubricant. 

PureNSM was among the first companies to use Nu-Mag in its formulations, which enabled the company to expand into tabletting. “Before Nu-Mag, tabletting was simply not an option for us,” Thorvaldsson said. But last year the company was selected to manufacture chewable lutein tablets for export to China. 

Because the formulation contained more than 10 herbs and couldn’t include any traditional excipients, it was nearly impossible to compress. “The powder was incredibly sticky and wouldn’t run on the press without the dies plugging or the tablets picking and sticking to the punches,” Thorvaldsson said. “Our operators could run the tablet press for maybe 30 minutes before they had to shut down production to clean the punches and dies.” 

According to Moreno, even those tablets didn’t pass muster. “We couldn’t create a quality tablet,” he said. “We could compress the material, but after 5 minutes off the press, the tablets would cap.” 

Once Nu-Mag was added, the force required to eject the tablets decreased, which eliminated the plugging, picking, sticking, inconsistent weights, and capped tablets. The addition requires operators to sift the Nu-Mag together with two of the formula’s highest-volume ingredients, a step that prevents the oils in Nu-Mag from forming balls and beads during blending, Moreno said. The preblend is then combined with the remainder of the ingredients for 20 minutes in a V-type blender. 

At a usage level of 5 percent (typical usage is 0.5 to 3 percent), Nu-Mag enabled the tablet press to run for more than 6 days straight with no unscheduled downtime for cleaning. Without the picking and sticking, tablet weights remain steady. 

“I expected that the Nu-Mag would create better tablets, but I honestly didn’t think that it would allow the press to run as fast as it did,” Moreno said. “I expected that I would start the press and have to clean it halfway through the job because the powder would stick to the dies and punches. But we didn’t have any problems.” The company estimates tabletting speed increased by more than 250 percent after adding Nu-Mag because it eliminated the need for unscheduled cleaning. 

The company’s success with those first tablets prompted Thorvaldsson to plan for more projects. “We are looking forward to increasing our tabletting capacity and looking to add more tableting equipment.”

Reference 

1. Expanding clean label excipients globally. Steve Peirce and Steve Dybdal. PowerPoint. Online.