BMP testingFruit, vegetables and their residues
Pineapple peels — BMP: 2 studies, weighted mean 194 m³ CH₄/t VS
Pineapple peels are an acidic, sugary and fibrous waste of tropical fruit processing; the results of several studies differ so greatly that caution is required.
Photo PattayaPatrol / Wikimedia Commons, licence CC BY-SA 4.0, source file; changes: cropping
- Weighted mean
- 194m³ CH₄/t VS
- Range
- 32–357m³ CH₄/t VS
- Records
- 2studies
- Publications
- 2sources
- Temperatures
- 35 °Cof the test
Methane in biogas
Medium methane content · ≈ 5.2 kWh/m³ of biogas
estimate from the substrate type The collected studies contain no measurement. The interval follows from the approximate composition (carbohydrate-dominated (no protein or fat characteristics)) and the yields of compound groups according to FNR.
Rating for biogas plants
not rated — editorial rating for biogas plants
Not rated: no dry matter or volatile solids in the data. We calculate the rating when the dry matter and volatile solids of the material are known.
Add to the co-digestion calculator CSV data
BMP curves from 2 studies
Weighted mean Individual records
Dashed lines are a model curve (first-order kinetics, B(t) = B₀·(1 − e−kt)); the end point comes from the publication. All curves are model curves.
Cumulative methane production over the test [m³ CH₄/t VS]. The thick line is the weighted mean of all records (194); dots mark the end values given in the publications. Point at the chart to read values; click a legend item to hide or show a record.
Records and sources
Download CSV| Source | BMP m³ CH₄/t VS | Temperature | Sample | Curve |
|---|---|---|---|---|
| Muenmee i Prasertboonyai (2021) DOI | 32 | — | Pineapple peel | end point (model curve) |
| Gunaseelan (2004) DOI | 357 | 35 °C · mesophilic | pine apple peels | end point (model curve) |
| Weighted mean | 194 | arithmetic mean 194, SD 230 | ||
Typical composition
- Volatile solids (VS)
- 93.2 % DM (range 93.2–93.2)
Median and range of the determinations reported in the publications behind this substrate's BMP records (read from: MY-D); dry matter: 0 determinations, volatile solids: 1 determination. No DM in the sources – the calculator has to ask for a value.
Sources: Gunaseelan (2004).
The composition of the raw material varies between batches — for plant calculations use an analysis of your own sample. The calculator inserts typical values automatically.
Process properties
Low confidence: the description is based on general characteristics of the substrate group, not on studies of this material. Treat it as a hint to be verified.
No published process studies
The literature we use does not describe the advantages or drawbacks of digesting this substrate beyond the BMP test results. Below are process characteristics assigned on the basis of the type of material — an editorial classification, not a study result.
- fibrous
- lignocellulose, long fibres → floating layer, harder mixing, slow degradation
- slowly degrading
- slow degradation, requires a long retention time
- seasonal
- seasonal availability — requires storage
- variable composition
- high variability of composition between batches
- dilutes the feed (low DM)
- low dry matter, dilutes the feed
- acidic
- low pH of the substrate (silages, stillage, whey, fruit)
Co-digestion — what to combine it with, what to watch out for
- combines well
substrates: easily degradable — e.g. Maize silage (whole crop), Food waste, Sorghum, whole crop, Whey, Beet leaves and tops
In BMP studies, easily degradable substrates increased the yield of the mixture with slurry (synergy in some mixtures).[1]
Dosing
No source limits on the dose for this substrate.
Sources of the process data
- Biochemical methane potential and biodegradability of complex organic substrates
- Potential Biogas Production Generated by Mono- and Co-digestion of Food Waste and Fruit Waste (Durian Shell, Dragon Fruit and Pineapple Peel) in Different Mixture Ratio under Anaerobic Condition
- Biochemical methane potential of fruits and vegetable solid waste feedstocks
- Improvement of fruit and vegetable waste anaerobic digestion performance and stability with co-substrates addition
- Effects of size and thermophilic pre-hydrolysis of banana peel during anaerobic digestion, and biomethanation potential of key tropical fruit wastes
- Effect of particle size on biogas generation from biomass residues
The co-digestion calculator will assess a specific mixture containing this substrate.
What it is and where it comes from
Pineapple peels (Ananas comosus) are a waste from the production of canned goods, juices and cut fruit. Alongside the peels, cores and leaf crowns are also produced. Pineapple is not grown in Poland, so the material appears only in comparative analyses and at selected plants processing imported fruit. In producing countries, such as those of South-East Asia, the peels form a significant waste stream.
Properties relevant to digestion
The peels are moist, and in the dry matter, alongside simple sugars and sucrose, there is a significant fibre fraction (cellulose, hemicellulose) and lignin in moderate quantity. Pineapple is an acidic fruit, so the material lowers the pH of the feed and requires a buffer. It also contains bromelain, a proteolytic enzyme whose effect on fermentation is not well documented. The high sugar content means rapid hydrolysis and a risk of overloading with acids, and the seasonality of processing complicates regular dosing.
How to read the spread of results
The dataset contains several records from several studies and the spread here is extremely large: the results differ several-fold. This arises from the fact that one of the studies gives the value in ml/g VS without explicit normalisation to standard conditions, and the samples differ in preparation, pineapple cultivar and degree of ripeness. The substrate-to-inoculum ratio, chopping, type of inoculum and the conditions of the test in small bottles also matter. In view of such a large discrepancy, no quantitative conclusions should be drawn without your own test.
In biogas plant practice
Pineapple peels are introduced into co-digestion with manure or sludge, after chopping and in a moderate share, while monitoring pH and volatile acids. The material undergoes spontaneous fermentation quickly, so it is unsuitable for long storage. In Poland the practical significance is negligible. However, data from the literature show that, with acidic and sugary materials, the key is the ability to buffer the process, and not the yield from the test itself.
In pineapple-producing countries the peels are also sometimes processed into feed or compost, so their use in a biogas plant is determined by competition with other uses and by the cost of transporting the watery mass, and not solely by the energy potential.
Methodology in brief
BMP is the amount of methane obtained from volatile solids (VS) in a batch test, given in m³ CH₄ per tonne of VS (numerically the same as NmL CH₄/g VS in the publications) and converted to normal conditions (0 °C, 101.325 kPa). The weighted mean gives each publication a total weight of 1, split equally between its results for the substrate — a paper testing twenty varieties does not outweigh a paper with a single sample. In inter-laboratory programmes the unit is the laboratory (total weight 1), and within it the weight of a test grows with the number of bottles (replicates). Results after pretreatment (e.g. thermal, chemical, enzymatic) are shown separately and are not included in the mean.
Solid lines are curves measured in the tests. Where a publication gives only the final result, we draw a first-order kinetic model, B(t) = B₀·(1 − e−kt): only the end point comes from the publication, and the shape of the curve serves purely as visualisation — do not read the production on a particular day from it. For this substrate k = 0.245 d−1 was assumed (median of rate constants k reported in the sources and/or fitted to the mean measured curves).
The statistics describe the spread of published results — a descriptive compilation, not a meta-analysis or a guarantee of plant yield.
Bibliography
- Muenmee, S.; Prasertboonyai, K. (2021). Potential Biogas Production Generated by Mono- and Co-digestion of Food Waste and Fruit Waste (Durian Shell, Dragon Fruit and Pineapple Peel) in Different Mixture Ratio under Anaerobic Condition. Environmental Research, Engineering and Management 77(1), 25–35. DOI: 10.5755/j01.erem.77.1.25234 DOI
- Gunaseelan, V. (2004). Biochemical methane potential of fruits and vegetable solid waste feedstocks. Biomass and Bioenergy 26(4), 389–399. DOI: 10.1016/j.biombioe.2003.08.006 DOI
All sources of the site: bibliography.
Other substrates in the group “Fruit, vegetables and their residues”
Water spinach — BMP: 2 studies, weighted mean 141 m³ CH₄/t VS
141 m³ CH₄/t VS weighted mean from 2 studies
neutral — editorial rating for biogas plants≈57 %
Turnip — BMP: 2 studies, weighted mean 304 m³ CH₄/t VS
304 m³ CH₄/t VS weighted mean from 2 studies
neutral — editorial rating for biogas plants≈53 %
Head cabbage — BMP: 4 studies, weighted mean 260 m³ CH₄/t VS
260 m³ CH₄/t VS weighted mean from 4 studies
≈56 %
Rambutan peel — BMP: 3 studies, weighted mean 99 m³ CH₄/t VS
99 m³ CH₄/t VS weighted mean from 3 studies
neutral — editorial rating for biogas plants≈52 %