Bioenergetics: Open Access

Dark Fermentation: A Technique for Converting Food Waste into Bioenergy

Dylan Sabour^* Department of Energy, University of Malaya, Kuala Lumpur, Malaysia
^*Correspondence: Dylan Sabour, Department of Energy, University of Malaya, Kuala Lumpur, Malaysia, Email:

Received: 02-Jan-2023, Manuscript No. BEG-23-19883; Editor assigned: 04-Jan-2023, Pre QC No. BEG-23-19883 (PQ); Reviewed: 18-Jan-2023, QC No. BEG-23-19883; Revised: 25-Jan-2023, Manuscript No. BEG-23-19883 (R); Published: 02-Feb-2023, DOI: 10.35248/2167-7662.23.11.192

Description

A form of biological hydrogen synthesis is known as dark fermentation. In the absence of light and oxygen, facultative and obligate anaerobes carry out dark fermentation. Bacteria interact with the substrate during dark fermentation to produce hydrogen. Lignocellulosic biomass, carbohydrate materials like industrial wastewater, crop residues containing sugar, and municipal solid waste serve as the substrate for the dark fermentation. The efficiency of the dark fermentation in the first step is significantly impacted by the pre-treatment of the biomass. The type of microbe used and the substrate's sugar level are the other factors that can affect efficiency.

The scientific community has been inspired to transform food waste into resources with additional value as a result of the rise in food waste generation. Due to its purity, high energy content, and ability to reduce global warming, hydrogen energy offers a sustainable alternative to fossil fuels. This study looks into the effects on the process stability and energy recovery of producing batch fermentative biohydrogen from food waste.

Numerous renewable organic wastes have been investigated as potential substrates for dark fermentative biohydrogen production, including sake lees, cassava, sago, glycerol, rice straw, vegetable waste, food waste, date seeds, sugarcane molasses, corn stover, alligator weed, oil palm sap, and wheat straw. Another renewable organic waste that is being investigated closely as a substrate for biohydrogen generation is Palm Oil Mill Effluent (POME), a wastewater produced in significant quantities during the palm oil extraction process. It has been researched to employ both pure and mixed cultures as the inoculum in the dark fermentation reactor.

Because there are a variety of microbial communities in a mixed culture system that may quickly degrade a variety of substrates, it is generally more advantageous and practicable than a pure culture system. Additionally, it is not necessary to maintain a tight aseptic condition, which simplifies handling and lowers operating costs. It is nevertheless a very biochemically complex environment due to the coexistence of biohydrogen producers with non-biohydrogen producers and biohydrogen-consumers like methanogens and homoacetogens in the mixed culture. Despite the numerous research conducted, there is still a lack of knowledge regarding the biological processes involved in dark fermentation for the production of biohydrogen, including the particular microbial community and trophic interactions. This aspect provides a more accurate description of the methaneproducing fermentation systems.

The traditional definition of a microbiome is a group of microorganisms with specialized traits and metabolic processes that interact with their surroundings to create a particular ecological niche. The term "microbiome" or "microbiota" refers to an assemblage of living microorganisms, which includes bacteria, archaea, fungi, microalgae, and protists but excludes phages, viruses, plasmids, prions, viroids, and free DNA. The term "microbiome" refers to the microbiota and its structural components, metabolites/signal molecules, and the surrounding environmental factors. The microbiomes contain free DNA, viroids, plasmids, prions, phages, viruses, and plasmids.

In a batch reactor, mixed culture was used to produce bioenergy from food waste at a thermophilic temperature. The first stage of thermophilic biohydrogen generation was tuned for initial pH (5.0–9.0) and then for C/N ratio (10–50). The second stage of thermophilic bio methane production was then tuned for an initial pH range of (6.0–10.0).