March 15, 2023

Zoning Board Meeting Will Address Application for Coffee Roasting Variance

To the Editor:

I’m writing to alert residents of the Witherspoon-Jackson and Community Park neighborhoods to an upcoming meeting of the Princeton Zoning Board of Adjustment (ZBA) next Wednesday, March 22 at 7:30 p.m.

At that meeting, the ZBA will continue hearing an application for a zoning variance to operate a coffee roasting facility at 300 Witherspoon Street (the old Packet building).

In case readers don’t know, coffee “roasting” is not the same thing as “brewing.” Roasting removes (and puts into the air) various unpleasant smelling chemicals, so that what we brew in our kitchens can smell and taste good.

According to the Centers for Disease Control National Institute for Occupational Health and Safety (NIOSH) bulletin on coffee roasting, the process “naturally releases diacetyl, 2,3-pentanedione, other volatile organic compounds (VOC’s), and gases such as carbon monoxide and carbon dioxide.” The bulletin goes on to discuss the impacts of airborne coffee dust on persons with asthma.

These VOC coffee roasting emissions do not have a pleasant smell. The applicant acknowledges a possible odor problem and proposes to partially scrub their emissions by means of an afterburner (Clean Stream Company, Tampa, Fla.), which removes some but by no means all emissions, according to company sales literature.

Once airborne emissions are picked up by prevailing winds, all people who live, work, or study in lower Witherspoon-Jackson, at Community Park School, at Community Park Pool, or in residential areas east and west of the roasting site are at risk of smelling/breathing VOC emissions and noxious fumes that have escaped the partial scrubbing of the afterburner.

This variance is needed because existing zoning prohibits “food processing” and “manufacturing” in all sections of Princeton. The applicant is proposing to roast coffee not only for use on his premises, but also for packaging and sale to other businesses, such as “restaurants and other cafes.” Opponents to the granting of the variance believe that this activity is classic “food processing,” and is exactly what our zoning laws are intended to prevent.

If you feel air quality is a meaningful issue to you, then I urge you to attend the Zoom-only meeting of the ZBA at 7:30 p.m. on March 22 by logging on to (More log-in information is at

Whether you think coffee roasting is a good idea or a bad idea, please take the time to become informed and, if you desire, register your opinion during the public comment session at the March 22 ZBA Zoom meeting. 

Owen Leach
Witherspoon Street