Can you eat sprouted beans?

In this article, we will answer the question “Can you eat sprouted beans?” and discuss what are the risks of eating bean sprouts.

Can you eat sprouted beans?

Yes, you can eat sprouted beans. Legumes are known to have reduced digestibility due to the presence of many anti-nutrients in their composition. When the beans are sprouted, their digestibility can be increased.

Sprouting of legumes increases protein and carbohydrate digestibility, enhances some of their vitamin contents, reduces the antinutritional factors and improves their overall nutritional quality.

Sprouted beans should be eaten cooked, as the simple sprouting procedure is not able to completely eliminate the anti-nutrients of the beans (2). 

What are the benefits of sprouting beans? 

The benefits of sprouting beans are the reduction of the amount of anti-nutrients in the beans and the increase of the mineral extractability and protein digestibility of the legume.  

Legumes are known to cause digestive discomfort, as they contain saponins, tannins and phytates, which reduce the digestibility, and reduce the absorption of some nutrients, which could lead to malnutrition. The anti-nutrients lectins, oxalates, phytates, phytoestrogens, and tannins, although having some health benefits, can be toxic when ingested in large doses.

During the different stages of germination several enzymes become active, inducing metabolic changes that take place of germination that influence the bioavailability of essential nutrients and reduction of the amounts of these anti-nutrients (3).

What are the risks of eating sprouted beans?

The risks of eating sprouted beans are related to food safety, as beans carry microorganisms which multiply during the germination of the seeds. 

Beans are contaminated in many ways, such as in the field and during harvesting, storage and transportation. The bacteria originated from soil or fecal origins can then attach to the seeds and survive for an extended period of time under dry conditions (1).

Several studies report that there are numerous pathogenic bacteria that may be present in the seeds of sprouts. Of particular note are E. coli O157:H7 and Salmonella enterica, which are associated with large food outbreaks due to the ingestion of germinated seeds.

It is necessary to clean and to cook sprouted beans prior to consumption. Sprouting does not eliminate the anti-nutrients completely and at the same time, favor microbial multiplication. Heat treatment applied to germinated beans will both extend the reduction of anti-nutrients and the reduction of the microorganisms. 

What to be aware of when eating sprouted beans?

When eating sprouted beans, you should be aware of the correct preparation and cooking of the beans, in an improved way as when preparing and cooking conventional dry beans.

Because the sprouting favors microbial proliferation, germinated beans should be sanitized before being used. An overnight soak of seeds in tap water caused a 10-fold increase in aerobic plate counts, according to studies (4). 

For safe seed germination, the USDA recommends using chlorine at 20,000 ppm to treat seed sprouts. When low levels of chlorine are used, there is no satisfactory reduction in the microbial load, while higher levels of chlorine result in undesirable organoleptic reactions.

After being properly cleaned, sprouted beans must be fully cooked to ensure satisfactory reduction of tannins, oxalates, phytates and lectins of the beans, which quantity was only partially reduced through germination. 

Cooking legumes improves their texture, palatability and nutritive value by gelatinization of starch, denaturation of proteins, increases nutrient availability and inactivation of heat labile toxic compounds and other enzyme inhibitors and make the food safe by killing pathogenic bacteria.

If the beans are to be used to produce bean sprouts, it is still necessary to sanitize the sprouted beans or to cook at a minimum temperature of 55°C. A study showed that heat treatments at 55°C may be an efficient way to treat some types of seeds prior to sprouting, thus eliminating the need for higher concentrations of chlorine. 

What are the nutrients found in sprouted beans?

The nutrients found in sprouted beans after being steamed are similar to the ones found in cooked conventional non-sprouted beans, with improved mineral extractability and carbohydrate digestibility (2).  

According to studies, while the iron and zinc extractability of the non-sprouted beans were 5.7% and 42%, respectively, the extractability of these minerals after sprouting and steaming were 28% and 52%, respectively. 

The carbohydrate digestibility improved from 46% to 48.5% and the protein digestibility was increased from 15 to 25%. 100 g of Sprouted beans contain on average 24 g protein, 1.2 g fat and 4.8 g fibers and 57 g carbohydrates. 

Other FAQs about Bean sprouts that you may be interested in.

Are alfalfa sprouts safe to eat?

Are wild about sprouts safe to eat?

Can you freeze bean sprouts?

Conclusion

In this article, we answered the question “Can you eat sprouted beans?” and we discussed what are the benefits and the risks of eating sprouted beans.

Reference

  1. Hu, Haijing, John J. Churey, and Randy W. Worobo. Heat treatments to enhance the safety of mung bean seeds. J food prot, 2004, 67, 1257-1260.
  2. Nakitto, Aisha M., John H. Muyonga, and Dorothy Nakimbugwe. Effects of combined traditional processing methods on the nutritional quality of beans. Food sci nutr, 2015, 3, 233-241..  
  3. Uppal, Veny, and Kiran Bains. Effect of germination periods and hydrothermal treatments on in vitro protein and starch digestibility of germinated legumes. J food sci technol, 2012, 49, 184-191.   
  4. Sprouts. Colorado State University.