Dogs and cats approached and ate the microbial-protein bowl first in an in-home test

MicroHarvest is a European company that produces protein ingredients through fermentation and targets pet food as its first market. In the study, both species were more likely to approach and eat the microbial-protein bowl first.

How Sense Test ran the bowls

Each pet was offered both diets in two bowls at the same time, in its own home, for four consecutive meals over two days.

What Eurofins found in both diets

The authors commissioned Eurofins Food Testing Portugal, an independent laboratory, to analyze both kibbles for proximate composition, amino acid and fatty acid profiles, selected minerals and targeted volatile compounds.

The volatile screen found none of the analytical markers typically linked to off-flavors, in either diet. That matters because an off-note is the most obvious way a new protein loses at the bowl. The screen rules out that explanation for a loss without explaining the win, and the authors say only that the diet's analytical profile may support the preference.

For a formulator, the lab package may be as useful as the intake numbers. An independent lab confirmed comparable macronutrient composition between the diets, which suggests the preference did not come down to one bowl simply being richer.

Funding and a tighter claim after review

MicroHarvest funded the work, paid both authors' salaries and helped conceive and prepare the manuscript. Cruz is the company's co-founder and chief technology officer, a detail eFeedLink put near the top of its coverage. The strongest objection is the obvious one: a company testing its own ingredient, in a small panel of pets, over a handful of meals.

One thing answers part of it: the analysis of the diets was done by Eurofins Food Testing Portugal, an independent laboratory.

An earlier preprint of the paper called the work a sensory acceptance study and described the control diets as nutritionally equivalent. The PLOS One version calls it a food preference study. For an ingredient buyer or formulation lead, the published wording is the one to quote.

The longer feeding trial ahead

Fish and poultry have traditionally been the primary protein sources in pet food, according to the study. The PLOS One authors point to concerns about the long-term availability and environmental impact of animal proteins as the reason fungal, yeast and bacterial proteins keep drawing interest.

For brands that have treated fermented protein mostly as a sustainability line, this adds a palatability data point gathered in homes, where pets actually eat. For brands that rely on fish meal for bowl appeal, it's a reason to put a microbial ingredient on the trial bench.

The authors name long-term palatability and health outcomes as the next questions. A multi-week feeding study that includes cats is the result that would confirm this read or break it.