Research declares Apples as a source to 100 million bacteria

A new study published in Frontiers in Microbiology demonstrates that organic apples are more prone to a diverse and balanced bacterial community, which is one of the main reasons why they are healthier and tastier than conventional apples. Moreover, these are also better for the environment.

According to Professor Gabriele Berg, of Graz University of Technology, Austria, the bacteria, viruses and fungi present in our food are ultimately responsible for colonizing our gut. When we cook these food items, the bacteria are killed, hence raw fruits and vegetables form the most important sources for gut microbes.

In order to help choose colonic colonists wisely, Gabriele Berg and his team examined the microbiome of apples, which also forms to be world’s most popular fruits.

“83 million apples were grown in 2018, and production continues to rise,” reported Berg. “But while recent studies have mapped their fungal content, less is known about the bacteria in apples.”

For the study, researchers compared the bacteria present in store bought apples with those present in organic apples. For this, the peel, flesh, seeds, stem, calyx and the part where the flower grows were separately analyzed.

The results conveyed that the amount of bacteria present in organic and conventional apples were the same. Experts suggest that majority of bacteria were present in the seeds and the flesh. Hence, the scientists suggested that if the core of the apples is discarded, the intake of bacteria falls closely to 10 million. However, the study also focuses on whether these bacteria are good for us.

Experts believe, more the variety of bacteria, better for gut health. Organic apples hence have a better edge when it comes to maintaining gut bacteria. Berg reports that 240 g of apples contain roughly 100 million bacteria. Moreover, “Freshly harvested, organically managed apples harbor a significantly more diverse, more even and distinct bacterial community, compared to conventional ones,” commented Berg. “This variety and balance would be expected to limit overgrowth of any one species, and previous studies have reported a negative correlation between human pathogen abundance and microbiome diversity of fresh produce.”

A specific group of bacteria- Escherichia-Shigella which includes pathogens is known to be present in conventional apples, whereas Lactobacilli and Methylobacterium which has a probiotic frame are known to be present in organic apples.

“Our results agree remarkably with a recent study on the apple fruit-associated fungal community, which revealed specificity of fungal varieties to different tissues and management practices,” according to Birgit Wasserman, lead author of the study.

The concluding analysis of the study shows that apple microbiome- bacteria and fungi present in the apples is more diverse in comparison to organically grown fruits.

“The microbiome and antioxidant profiles of fresh produce may one day become standard nutritional information, displayed alongside macronutrients, vitamins and minerals to guide consumers,” reckons Wasserman. “Here, a key step will be to confirm to what extent diversity in the food microbiome translates to gut microbial diversity and improved health outcomes.”