Biogas Production from Alfalfa Enhanced by Fruit Waste and Microbes

Biogas Production from Alfalfa Enhanced by Fruit Waste and Microbes
by Clarence Oxford
Los Angeles CA (SPX) May 07, 2025

Researchers in China have developed a novel method to enhance biogas production from alfalfa by incorporating fruit waste and anaerobic microbes, according to a new study published in mSphere. The approach leverages the co-fermentation of alfalfa with fruit waste and Lactobacillus acidophilus, leading to increased methane yield and improved nutrient content in the remaining biomass.

Alfalfa, typically valued as a high-protein livestock feed, can also serve as an efficient biogas source when processed through anaerobic digestion. This process breaks down organic matter in the absence of oxygen, producing a mix of methane and other gases. The study, conducted by researchers at Guizhou University College of Animal Science, explored the impact of adding two components to the fermentation mix: rose hip pomace and L. acidophilus.

"The process offers an attractive opportunity to increase methane production from fruit waste," said Qiming Cheng, Ph.D., a microbiologist at Guizhou University. He highlighted the economic and environmental benefits, noting that plant biomass can serve as an inexpensive, stable source of clean energy and a potential alternative to fossil fuels.

The first additive, rose hip (Rosa roxburghii) pomace, is a byproduct of juice production and is widely grown in the Guizhou region. Utilizing this waste reduces the cost of raw material transportation and supports rural biogas initiatives. The second component, L. acidophilus, is a well-known probiotic that facilitates anaerobic digestion.

Testing over a 50-day period revealed that the combination of rose hip pomace and L. acidophilus had a synergistic effect, significantly enhancing biogas production. Samples treated with both additives showed a 33% increase in methane output after just 3 days, compared to untreated samples. The combined treatment also accelerated acidification, promoting the growth of beneficial lactic acid bacteria, including Lactiplantibacillus plantarum, while reducing the presence of less desirable species like Lactococcus lactis, Kosakonia cowanii, and Enterococcus mundtii.

This improved microbial profile contributed to more efficient methane production, positioning the method as a promising approach for advancing rural biogas systems and reducing agricultural waste.

Research Report:The potential of biogas production and effects of alfalfa silage under the synergistic influence of Lactobacillus acidophilus and Rosa roxburghii pomace waste on the fermentation quality and bacterial community