The US researchers injected juice, pomace, and pulp – in vivo – into the amniotic fluid of the developing embryo inside the broiler chicken egg. After the eggs were hatched, relevant samples were collected for analyses.
Apples are comprised of bioactive constituents such as phytochemicals and prebiotics that could help intestinal health and the gut microbiome, said senior author Elad Tako, associate professor of food science in the College of Agriculture and Life Sciences (CALS) and a co-author of the paper.
The team found that introducing apple juice and pomace into the egg can increase the young chicken’s transport system for amino acids, improve the bioavailability of iron, boost the microbial populations in the animal’s large intestine and support the growth of potentially beneficial gut bacteria.
In particular, they noted the effects of the supplementation of apple pomace on gut health:
“The potential health benefits of apple pomace are revealed in this study, evident by reducing iron metabolism protein gene expression (DcytB), increasing villi surface area, and decreasing crypt depth, increasing Paneth cell count per intestinal crypts, and increasing potentially beneficial gut bacteria (Clostridium spp.),” said the authors.
Dufourny et al. (2021) previously assessed the effects of apple pomace on intestinal morphology and microbiota in weaned piglets. They found the pomace to increase Clostridia abundance and duodenal and ileal villi length. “Our results agree with the significant findings of this study. This further establishes the role of apple pomace to modulate Clostridia groups in both animal models, which leads to improvements in gut health and intestinal homeostasis.”
However, the researchers indicated the need for long-term studies to further establish potential health benefits of using apple soluble extracts.
Alternatives to landfill
For juice and apple production, about 33.4 million bushels of apples were used in 2021-22, according to the US Apple Association. Nearly 175,350 metric tons of apple pomace – the fibrous waste – is produced annually and typically sent to landfill, according to the paper. This damages the environment, as it disrupts the carbon-nitrogen ratio of soil due to the pomace’s sugar content.
The researchers said this was an initial study to demonstrate the potential effect for adding apple waste to broiler feed. “Potentially, we’ll be upscaling industrial waste that is currently being discarded. That’s sustainable,” said Tako.
Funding for the research was provided by the National Institute of Food and Agriculture, US Department of Agriculture (USDA).
