Technical Articles

Sales heat up fast for an African Hot Sauce.

High shear rotor/stator mixer the key to replicating an African recipe
and turning up the heat in the USA.

The challenge of preparing an authentic African hot sauce for the US market was a easy assignment for Green Garden Foods of Kent, Washington. This custom dressing and sauce manufacturer is nationally known for its ability to source even the most exotic ingredients and replicate complex recipes precisely.

  • White sweet potatoes with an authentic African texture? No problem.
  • Hot chili peppers that taste more like Cape Town than Mexico City? No sweat.
  • Matching the texture of the original sauce on a high-speed, high-volume process line? Easy.

A Ross high-speed rotor/stator mixer provided the intense shear necessary to puree the solid ingredients quickly and the flexibility necessary to fine-tune the process and until it was running perfectly. “Our client was adamant,” says Kyle Anderson, technology chief at Green Garden Foods. “The flavor, texture and appearance all had to be 100% genuine.

“Ethnic sourcing is routine for us. But to find the best way to puree the sauce, we did a lot of homework. We defined our requirements for performance, maintenance and cost-efficiency. We talked with many plant engineers who use high shear rotor/stator equipment made by a variety of manufacturers. Then we contacted Ross.”

Anatomy of a Rotor/Stator Mixer

Rotor/stator mixers operate with a high speed rotor that turns inside a stationary stator. (See photo.) The rotor draws solid and liquid batch material into the high shear chamber and expels it laterally at high speed through openings in the stator. Intense mechanical shear occurs at the point where the rotor blade crosses each opening in the stator. That’s where solids are broken apart – virtually instantly.

Rotor/stator technology has advanced dramatically during the last 10 years, but for many the familiar single-stage rotor/stator generator still offers the best combination of performance and value. The mixer operating at Green Garden Foods is a single-stage, 30 hp batch unit with a 7" diameter rotor and an electronic variable speed control that enables the operator to adjust shear rates and throughput. Batches average 40 gallons, and the mix cycle, according to Kyle Anderson, is “only a minute or two longer than it takes to add all the ingredients.”

Specifying a Rotor/Stator Mixer

The checklist used at Green Garden Foods provides a useful reference for anyone considering a rotor/stator mixer:

  • Performance - Fast mixing cycles with adjustable speed and shear rates.
  • Versatility - Interchangeable rotors and stators for other applications.
  • Engineering - Sanitary design, solid construction, local engineering resources, aggressive R&D.
  • Maintenance and support - Easy cleaning, fast service, immediate availability of US-made parts.
  • Value - Low initial price, high overall cost-efficiency, and immediate delivery.
  • Future value – A stable product line designed for smooth scale-up to meet future needs with predictable results.

A Mixer That Opens New Markets

Green Garden Foods originally obtained its high shear mixer to produce the African Hot Sauce, but it has turned out to be even more productive as a tool to land new business.

“The flexibility of the mixer has been terrific,” says Ms. Anderson. “We’ve expanded our capabilities and taken on a whole spectrum of new products made with this mixer - salsas, Mexican hot sauces, Asian sauces, sandwich spreads and dressings.

“Now we’re also making an emulsified dressing with red onion – with excellent stability, uniform droplet size, and great texture,” she says. “The possibilities keep expanding.”