Georgia-based start-up looks to bring more bugs to aquafeed

Grubbly Farms is in the process of scaling production of a bug-based feed ingredient for salmon and trout, but for the moment, the company is bringing more insects to poultry production.

The Georgia-based company started in 2015 as the brainchild of cousins Sean Wagner and Patrick Pittaluga. The two have set a goal of mass producing a feed ingredient made from the larvae of black solider flies, said Wagner.

“I’d read about the black solider fly and how Europe and Africa were really pushing for the large scale production of insects and we saw opportunities in the market,” he told FeedNavigator. The fly could offer a way to generate a sustainable protein source from waste food products, he added.

“The end goal is to produce a protein source that will compete with fishmeal at the commercial level,” he said. “Fishmeal has increased in price about 200% in the last several years [and it is] still the main in ingredient in most aquaculture feeds.”

The focus on offering a replacement for fishmeal and fish oil came from an understanding of the limited nature of the product, he said. However, until the company scales up to that level of production, it is turning out limited amounts of a bug-based feed supplement for chickens.

Project history and details

Work on the project started with raising the flies in a laundry room to work out ways to simulate the sunlight needed for fly growth and development, said Wagner, as that process can be one of the more difficult parts of the production system.

The company also took part in a pre-accelerator program at Georgia Tech and the CreateX program Startup Summer, he said. Those efforts helped the duo scale up their project and partner with Kennesaw State University to move the fly growth operation into a greenhouse on campus.

Production has since outgrown that facility, said Wagner. The company moved into a warehouse about six weeks ago and is building out to fill the expanded capacity and create a higher-density production system.

The fly larvae are raised in food grade, pre-consumer waste food obtained through a partnership with a bread company and a juice producer, said Wagner.  

“We’re still in the R&D phase,” he said. “The current warehouse will recycle about 1 to 2 tons a day – and [generate] about 200-300 pounds of larvae a day, but we’re still building out a feeding system.”

The next facility would start with capacity to recycle about 10 tons of food waste and scale up to 20 or 25 tons at full production, he said.

The current systems hatches eggs laid by the black soldier flies and then allows them to grow in the food waste, as the larvae start to reach the pre-pupa stage they migrate up and out of the grow bin, he said. At that point the majority are harvested and dried while some are left to become flies and continue the process.

The company is continuing to work on scaling up their production, said Wagner. Eventually, the company will need to produce about 15,000 pounds of dried larvae a week for use in feed.

“Even speaking with the smallest feed mills they need about 15,000 pounds every week and we’re not at that level,” he said. “We can’t just jump into that.”

In the interim, the company is dehydrating the larvae produced and selling bagged quantities for use with chickens, he said. The product is not intended to be used as a complete feed as it only contains the dried fly larvae.

“One of the main things that we’re really advertising is that the solider flies have a relatively high calcium [level] to body weight, which is great for egg production and [high] lysine, which is great for feather production as well,” he said.

Future plans

 In addition to making feed from whole, dried larvae another future step will be to evaluate specific products made from pressing the larvae, said Wagner.

“In the future we will probably extract the lipid content – like how you extract the oil from seeds,” he said. “It boosts the relative protein up to about 60% so it will compete with fishmeal.”

Currently the company has been working with the US Department of Agriculture and US Food and Drug Administration to talk about the process and run digestibility studies using feed made with the dried larvae, he said. So far the work has demonstrated that the product does not hinder fish development.

Wagner said he sees additional markets opening in the future either for other aquaculture species or for livestock feed.

Another next step includes work with beta testers to use the pelleted feed and how much will be needed, he said. “We’re currently going through the TechStar accelerator and throughout that program we’ve been looking at beta testers,” he added. 

As with other insect production systems, there is a concern about how financially viable the operation would be, he said. “With our fully automated systems we think it will be able to compete with other protein sources at the commercial level, but that is one of the challenges we face as we move forward,” he added.