While beans are crops used since ancient times, beans in dog food are a relatively new ingredient in commercial diets. Their main purpose is to add plant protein and carbohydrates.
Contents
What are Beans?
Worldwide, beans are the most important pulses for direct human consumption.
They also play an important role in livestock nutrition and have recently been discovered as a novel ingredient for pet foods.
According to the AAFCO, dried beans in dog food shall always be “identified by variety”, e.g. navy beans or kidney beans[2].
The Food and Agriculture Organization of the United Nations (FAO) includes several species in its definition of beans[1].
However, only a few beans are used in dog nutrition:
- Common bean (Phaseolus vulgaris) or pinto bean, kidney bean, navy bean, green bean, etc.
- Lima bean (Phaseolus lunatus) or sugar bean, butter bean, etc.
- Mung bean (Vigna radiate) or moong bean, monggo beans, green gram, etc.
Soybeans or fava beans are beans in name only but are classified in other categories of legumes. Just like garbanzo beans which is just another name for chickpeas.
Common Beans in Dog Food
The common bean is an ancient crop that originated in Central and South America and was brought to Africa in the 16th century.
Today, beans are grown all around the world as a warm season legume for their edible dry seeds or green, unripe pods.
The seeds of common beans are kidney-shaped and can have many colors depending on their cultivar.
There are many cultivars and varieties of common bean:
- bush bean
- garden bean
- pinto bean
- kidney bean
- navy bean
- white bean
- pole bean
- black bean
Pods of some varieties can be eaten whole:
- green bean
- snap bean
- string bean
- french bean
Common bean ingredients in dog food recipes are mostly whole dried beans or ground bean flour.
Although pulses have been used in the pet food industry for over 2 decades, one 2013 study stated that dry beans had not been included in any commercial pet foods at this time[4].
So it’s a relatively new ingredient for dog food!
The common bean is rich in starch, protein, unsaturated fatty acids, and dietary fiber.
They can also be a source of minerals and some vitamins[3].
Common bean protein is primarily made up of the storage protein phaseolin[1]. But like other legume proteins, it is low in methionine. So it has to be supplemented with other sources!
Beans contain a moderate amount of purines, if that’s important to your dog.
And just like us, our dogs can’t eat raw beans!
Common beans can cause flatulence.
And they feature some anti-nutritional factors like enzyme inhibitors, phytic acid, lectins or saponins.
For example, bean protein is able to inhibit the activity of the enzyme α-amylase (the enzyme that digests starches).
And some beans can naturally contain toxic levels of lectins.
To make pulses like green beans in dog food digestible and inactivate anti-nutritional compounds, they need to be cooked.
Common beans in dog food might have prebiotic properties[4].
Lima Beans in Dog Food
Lima beans are only used in very few dog food recipes. They are also called butter bean, java bean, or sugar bean.
This crop was developed in Central and South America. Today, lima beans are cultivated throughout the tropics.
Lima beans have a creamy taste and provide flavor. They are low in fat and fiber but rich in protein and starch[1].
They also provide some minerals like iron or manganese.
Again, there are some anti-nutritional factors such as phytic acid, protease inhibitors, and lectins.
And: Raw lima beans are toxic to dogs!
They also contain cyanogenic glucosides (linamarin, lotaustralin) and linamarase, an enzyme that can convert these compounds into highly toxic hydrogen cyanide.
Lima beans have to be processed to make them edible to dogs.
Mung Beans in Dog Food
India is the largest producer of mung bean, but they are widely grown in Southeast Asia, Africa, South America, and Australia.
Other names for mung beans are monggo beans or green gram.
To our knowledge, they are not a common ingredient in commercial dog foods as of yet.
They provide lots of protein with an amino acid profile similar to that of soybean. They are also very rich in easily digestible carbohydrates, but low in fat and fiber.
Their phytochemical content (polyphenols) might even make them a functional ingredient with some additional health benefits[5].
The protein content is said to be especially high in sprouted mung beans. Naturally, mung bean sprouts for dogs are used as a healthy addition in homemade diets.
Overall, mung beans are considered an excellent nutritive legume.
But they are still legumes and contain some levels of enzyme inhibitors, tannins, and lectins[3].
So they should be soaked, cooked or extruded (which already happens in commercially prepared dog food).
Further Reading
[1] FAO 2017. Pulses and their by-products as animal feed (PDF). Chapter 2: Beans.
[2] AAFCO Official Publication. Chapter 6. Free Access.
[3] Feedipedia: Common bean (Phaseolus vulgaris), Lima bean (Phaseolus lunatus), Mung bean (Vigna radiate). 2015
[4] Kerr et al. Effects of Dietary Cooked Navy Bean on the Fecal Microbiome of Healthy Companion Dogs. PLoS ONE . 2013. https://doi.org/10.1371/journal.pone.0074998
[5] Kumar Ganesan & Baojun Xu. A critical review on phytochemical profile and health promoting effects of mung bean (Vigna radiata). Food Science and Human Wellness. 2018. https://doi.org/10.1016/j.fshw.2017.11.002