Safe, Easy, Low-Cost Produce Handling: Greens Spinners

Spinning leafy greens to remove excess water is a common practice that can increase wash-pack efficiency and increase product quality. Greens spinners that work well keep greens from being too wet going into storage, which reduces their shelf-life and can promote the growth of human pathogens. Greens spinners should be washable and properly sized for a farm’s volume of production. Manual-crank institutional grade spinners (5 gal.) are typically hygienically designed and can efficiently accommodate up to 25 lbs. of product. Converted washing machines can easily accommodate several times that amount, but they cost more and need to be properly converted to reduce risk of cross contamination. Similar-scale electric spinners, purpose-built for market-scale operations, can be more pricey than washing machine conversions, but are still an affordable alternative. Large industrial spinners, or greens lines with elevators and conveyors, have many desirable features but are not practical or affordable for smaller operations.

greens spinner
The 5-gal hand-crank "restaurant-scale" spinner (above) is the entry-level work horse for small-scale greens growers (up to 30 lbs of greens/session).  This one is friction fit into a DIY wooden frame that when screwed or bolted down holds the spinner tight, eliminating vibrations and increasing the efficiency and effectiveness of greens drying. Photo by Hans Estrin.

Design Goals

Body
  • Quick removal of water from leafy greens surfaces, without damaging produce.
  • Spinner basket is non-porous, easily removed, and can be cleaned completely.
  • Spinner unit is stable and easy to operate safely.
  • Spinner is positioned for efficient transfer of produce from wash station.
  • Spinner is big and fast enough to accommodate the farm’s typical harvest volume without causing a traffic jam.

Design Elements

Body
  • Removable spinner baskets are made of rugged plastic or stainless steel that can withstand repeated use and removal.
  • Manual spinners (2.5 or 5 gal. capacity) are used for a single worker processing 5 to 25 lbs. of greens in a typical processing session. Converted washing machines can handle up to 75 lbs. per session.
  • For manual spinners, a stable tabletop and well-maintained spinner gears support smooth and efficient spinning of a balanced, 3/4- full filter basket.  Many growers build custom table-top “bumpers” to snuggly secure the spinner table-top.
  • Converted washing machines have snug and stable basket inserts and are secured to the floor to prevent “walking.” Shut-off timers are installed to increase efficiency.
  • The exterior panels of converted washing machines may be safely removed to expose the frame and drum of converted washing machines. This can mitigate food safety risk by allowing the drum to dry more rapidly between sessions, inhibiting the growth of microbes and mold.

Benefits

Body
  • Proper spinning of leafy greens can increase shelf life and reduce food safety risk.
  • Appropriately sized spinners support wash-pack efficiency.
  • Removable, cleanable and dryable spinner components minimize risk of cross-contamination.

Photos

Body
washing machine greens spinner
A big step up from hand crank spinners:  This converted  washing machine spinner is bolted to a dolly for easy moving, and equipped with an on/off switch, timer, and drain extension.  Greens are spun in these red harvest baskets, which are easily washable. This setup can readily handle 20-50 lbs greens/ session  Dutchess Farm, Castleton, VT. Photo by  Hans Estrin
market garden greens spinners
These market garden spinners are purpose built stainless steels with similar volume to converted washing machines. They cost up to twice the price,, but are commercial grade, plug and play.  Photos Hans Estrin
large spinner
Larger commercial spinners (Capacity 30 gal or more) can be cost effective for larger operations cranking out 50 or more lbs of greens per session.  Jericho Settler's Farm, Jericho, VT.  Photo by Hans Estrin. 

Authors: Hans Estrin and Vern Grubinger, UVM Extension

This work is supported by the Food Safety Outreach Program Name, project award no. 2023-70020-40688, from the U.S. Department of Agriculture’s National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and should not be construed to represent any official USDA or U.S. Government determination or policy.

USDA NIFA logo