Do fermented foods have a role in pet nutrition?

Humans eat fermented foods all the time – yogurt, cheese, sauerkraut, kimchi – not to mention drinking fermented beverages such as wine and beer. Health benefits associated with the consumption of such foods ultimately led to the discovery of probiotics. To explore whether fermented foods have a role in enhancing the nutrition of pets, we should first look at the evidence in humans.

Health benefits in humans
Fermentation occurs when microorganisms such as bacteria or yeast grow. Lactic acid-producing bacteria and yeast are generally considered safe organisms for human consumption. Not only does fermentation produce acids that give food a tangy taste, but it also produces B vitamins such as thiamine, riboflavin, biotin, cobalamin and folic acid, as well as vitamin K. Several of these vitamins are considered essential to avoid nutritional deficiencies. As such, fermented foods are a source of essential vitamins. Moreover, these are natural, rather than synthetic, sources of vitamins.

Fermentation also produces bioactive peptides which can positively impact health. Examples of bioactive peptides include melatonin and GABA. Beneficial aspects of bioactive peptides include anti-cancer, anti-inflammatory, anti-diabetic, anti-microbial, anti-adipogenic (fat accumulation), anti-mutagenic (DNA damage) and anti thrombotic (blood clots). As an example, the production of the hormone GABA has been associated with anti-depressant and anti- diabetic benefits.

During fermentation, bacteria also produce exopolysaccharides which provide a thick protective barrier surrounding the bacteria to improve their ability to survive in their environment. Exopolysaccharides are made of unique polysaccharides that have been associated with immunomodulation, antioxidant and anti-cancer effects. Immunomodulation effects by exopolysaccharides have also been associated with alleviating influenza virus-induced infections.

Zooming in on vinegar
Specific products of fermentation have been associated with other health benefits. For example, vinegar (acetic acid) consumption has been shown to reduce after-meal blood glucose and insulin levels as well as improve the feeling of satiety. Vinegar has an anti-obesity effect and has been used to suppress immune-associated gut inflammation in a colitis model. Regarding nutrient absorption, vinegar is associated with improved calcium absorption.

Current developments in pet food
So, is it possible to create fermented foods for pets? In 1979, a US patent was granted to Mars which described a technique to achieve ‘long-term stabilization of proteinaceous food products for both human and animal consumption’. The patent specifies the addition of an inoculum using a probiotic organism to help achieve a shelf-stable food product.

While it is unclear whether the examples laid out in the patent meet the complete nutritional requirements of the pet, a method is presented that puts forth how a fermented product could be created as a pet food. Given that bacterial fermentation naturally produces vitamins, it would be interesting to understand how this technology could be leveraged to create a food product containing natural sources of vitamins. 

A number of small, innovative companies are currently making fermented diet components that are marketed specifically for pet consumption. For example, the Big Dog Natural and Dr. Mercola brands both sell fermented vegetables, while the Answers Pet Food brand sells fermented milk products.

Commercial challenges
Some challenges remain in terms of expanding the availability of fermented pet food. From a commercial point of view, fermenting the food increases the amount of time involved in the production process for the product. Additionally, fermentation can change the taste of the food, which may alter pet acceptance.

Underdeveloped opportunity
However, given the diversity of health-enhancing substances made by nature’s ‘mini-factories’ (i.e. microbes), fermented foods offer a unique, considerably underdeveloped opportunity to enhance pet health. For truly entrepreneurial companies looking for a novel product form, a complete pet food based on fermentation technology could represent a possibility to further expand the diversity of their pet product offerings and provide a health-enhancing point of difference in today’s competitive pet product environment.