Walnut hulling and curing

Black walnut processing can be broken down into key steps. 

Black walnuts are grown, gathered, hulled, cured, shelled, sorted and then consumed with various recipe-dependent steps happening prior to consumption.

Each step can be individually optimized or industrialized. With respect to growing, black walnuts cultivars with specific desirable traits can be intentionally planted rather than relying on wild stock. To gather, black walnut trees can be mechanically shaken to cause black walnuts to fall where and when wanted for easier collection. Industrial hullers are available for purchase and all deliver mechanical hull abrasion. Some hullers use water for hulling and some do not. Curing can be accelerated with added heat or forced air circulation. We know that shelling, sorting, post-processing and packaging can all be industrialized because Hammons Product Company in Missouri does this ever year.

The trouble with industrial scale solutions is that they tend to cost industrial scale money. If decentralized black walnut processing is to emerge, then, as has happened in almost every industry which first centralized and has since seen significant decentralization, the technology must evolve. We don’t know exactly what technology will enable cost-competitive decentralized black walnut processing.  We assume the answer isn’t readily available or else decentralized black walnut processing would already be widespread.

Our 2022 huller is on order and will fit in this tent. It requires water and has an electric motor.

Our initial approach is just as step above low-tech. Progressing walnuts through our process doesn’t happen automatically. Our process depends on people. People look through the walnuts we receive to make sure we are only processing walnuts that are in good shape. People remove the hulled and cleaned walnuts from the huller and put them through a sanitizing and sort step that involves rinsing them in a disinfecting solution and discarding the nuts that float. Our curing approach is passive but aided by solar heating and cured walnuts are unloaded from our dryers by people and then put into storage until they can be used. We use a very straightforward, hands-on approach. We have a process where some work is provided by electricity, some by gravity, some by water, some by the sun but mostly by people.

If we were processing on an industrial scale, this would be an unaffordable approach. However, because we don’t yet know what is needed to deliver cost-competitive distributed black walnut processing, we haven’t investing too much in any particular technology. We’re investing in learning by doing. This will eventually demonstrate exactly how much improvement is needed at every processing step and help us focus on first improving the steps that are the most important barriers to a cost-effective process. We take the same minimalist approach to the shelling, sorting and packaging which happens in our new building, the first licensed black walnut processing facility in New York State.

Our near-term objective is to deliver healthy food using a safe process that doesn’t cost too much to implement.

We’ll figure out how to do it faster and cheaper but still small-scale after we’ve mastered the basics.