Last month, meal-replacement startup Soylent voluntarily stopped selling its new-to-market nutrition bar and long-running powder after receiving reports from customers who became ill after consuming the meal-replacement products. Now, the company says it has pinpointed the cause of the issues: an algae-based ingredient called algal flour. 

Bloomberg reports that Soylent believes that algal flour — unique to the Food Bar and Powder 1.6 — is to blame for customers’ experiences with vomiting, diarrhea, and stomach pain, and it will stop using the ingredient in future batches of the products.

“We are releasing new formulations of our powder mix and meal replacement bars early next year,” Rob Rhinehart, Soylent’s co-founder and chief executive officer, tells Bloomberg. “Our new formulations will no longer contain algal flour.”

Algal flour, according to Bloomberg, is used as a vegan replacement for butter and eggs and is created from algae grown in fermentation plants that is then dried.

The ingredient was purchased by Soylent by TerraVia Holdings Co, which also provides the product to Unilever for use in lotions and soaps.

“Our algal flour has been used in more than 20 million servings of products, and we are aware of very few adverse reactions. In no cases was algal flour identified as the cause,” Mark Brooks, a senior vice president at TerraVia, tells Bloomberg.

Soylent also uses a version of the ingredient — algal oil — in its pre-made drinks, but says it has not received any complaints from customers related to those products.

Issues with Soylent’s products began in mid-October when the company announced it would voluntarily stop selling and advise customers to stop eating its Food Bar after receiving reports of people becoming ill after consuming the product.

The company then said it conducted an “aggressive investigation to uncover why people were having negative experiences after eating Soylent Food Bars.

The investigation included “product testing, an exhaustive industry search, and discussions with many of our suppliers,” the company said in a blog post. “Our tests all came back negative for food pathogens, toxins or outside contamination.”

At that point, the company says it began to shift its focus to whether any one ingredient could be triggering a food intolerance, noting that such an issue would explain why not all customers had become ill after eating the products.

During the review, the company says it noticed that a handful of consumers — less than 0.1%, according to Soylent — who consumed Powder 1.6 over the past several months reported stomach-related symptoms that were consistent with what Bar customers described.

Soylent then announced it would stop the sale of Powder 1.6 — which is designed to be mixed with water and consumed instead of solid food — and advised customers who have shown sensitivity to the product to discard whatever is left.

Despite the move, the company did not reveal at the time what ingredient it believed caused the issues.

Soylent says it will reformulate the Bar and Powder products to remove the common ingredient, with new products expected to be available in early 2017.

Still, Bloomberg notes that any kind of reformulation will take time, as extensive testing will be required before the products are put on the market.

Soylent Thinks It Found What Was Making People Sick: Algae [Bloomberg]

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