Evaluation of Common Supermarket Products as Positive Controls in Biochemical Methane Potential (BMP) Tests

Abstract

Biochemical methane potential (BMP) tests are commonly applied to evaluate the recoverable amount of methane from a substrate. Standardized protocols require inclusion of a positive control with a known BMP to check the experimental setup and execution, as well as the performance of the inoculum. Only if the BMP of the positive control is within the expected range is the entire test validated. Besides ignorance of this requirement, limited availability of the standard positive control microcrystalline cellulose might be the main reason for neglecting a positive control. To address this limitation, eight widely available grocery store products have been tested as alternative positive controls (APC) to demonstrate their suitability. Among them, Tic Tacs and gummi bears were very promising, although they are dominated by easily degradable sugars and so do not test for hydrolytic performance. Coffee filters exhibited a similar performance to microcrystalline cellulose, while whole milk might be chosen when a more balanced carbohydrate:protein:lipid ratio is important. Overall, the approach of predicting the BMP of a substrate based on the nutritional composition provided on the product packaging worked surprisingly well: BMP of the eight tested products was 81–91% of theoretical maximum BMP based on nutritional information and generic chemical formulas for carbohydrates, proteins, and lipids.

Biodegradation of Functionalized Nanocellulose

“…Biodegradation of CNFs in our BMP tests lead predominantly to biogas formation over the course of a few weeks, producing between 680 and 700 mL/g of biogas, representing over 80% CNF mass loss. This is consistent with the rapid and extensive mineralization of cellulosic materials typically observed. , Despite the efficiency of biogas production during CNF biodegradation, some of the carbon is converted into biomass, as is typical of biodegradation processes. This situation also holds true for functionalized CNFs.…”

“…This is consistent with the rapid and extensive mineralization of cellulosic materials typically observed. 28,82 Despite the efficiency of biogas production during CNF biodegradation, some of the carbon is converted into biomass, as is typical of biodegradation processes. This situation also holds true for functionalized CNFs.…”

Rapid Biological Reduction of Graphene Oxide: Impact on Methane Production and Micropollutant Transformation

“…These two were excluded from further data analysis. For all the conditions tested, an initial lag phase of about two days was noticed, which is quite common when microcrystalline cellulose is used as a substrate [44]. The two straight dotted lines of Fig.…”

Investigating the Energy Potential and Degradation Kinetics of Nine Organic Substrates: Promulgating Sustainability in Developing Economies

“…This involves evaluating parameters such as BMP ∞ (maximum methane potential), which signifies the highest achievable methane yield under optimal conditions and provides a benchmark for the biogas production potential of each material [12,17]. Additionally, BMP 1% (early methane potential) plays a key role in the selection process by offering insights into the initial methane production rate, allowing for quicker assessments and standardized criteria for experiment termination [18,19]. Further-more, considering BMP 90% (90% methane potential) provides a deeper understanding of the digestion kinetics, especially in terms of reactor efficiency and the time required to reach significant methane yields [20,21].…”