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Butters

Tucuma Butter

INCI Astrocaryum Vulgare Seed Butter. Also: Astrocaryum Vulgare Seed Butter, Tucuma Kernel Fat, Awara Butter.

Calculate a 100 % Tucuma Butter bar

Published values

Saponification value181.9–182.9 mg KOH/g (typ. 182.42)
Used by the calculator182.4 mg KOH/g (typical)
SAP for NaOH0.1300 g/g
Iodine value2.78–2.78 g I₂/100 g
INS (SAP − IV)180
Melting point30–32 °C (typ. 31)
Unsaponifiable matter

A bar made of 100 % Tucuma Butter

Hardness 82 above 29–54
Cleansing 76 above 12–22
Conditioning 1 below 44–69
Bubbly lather 76 above 14–46
Creamy lather 7 below 16–48

Conventional qualities summed from the fatty-acid groups; a single-oil bar is a reference point, not a recipe.

These two published numbers disagree. The saponification value on record is 182.4 mg KOH/g, but the fatty-acid profile below implies about 247 — a gap of 26 %. The two are not independent facts: chain length fixes the molar mass, which fixes how much lye a gram of fat consumes. So one of the two fields is wrong, or they were measured on samples that are not comparable, and the disagreement is upstream in the literature rather than in the arithmetic here.

The calculator uses the published value, because that is what the source says. If you are building a recipe with a lot of this ingredient, weigh the risk: at 26 % it would shift your lye by roughly that much for the portion of the batch it makes up. A certificate of analysis for your own lot settles it. The notes below record which documents were checked.

Fatty-acid profile

Fatty acidPublished range, %Used
Capric acid C10:0 · saturated 1.46–1.46 1.5
Lauric acid C12:0 · saturated 44–55 49.5
Myristic acid C14:0 · saturated 22–30 26.0
Palmitic acid C16:0 · saturated 6.94–6.94 6.9
Linoleic acid C18:2 1.48–1.48 1.5

Where these numbers come from

Revista de Ciencias Farmaceuticas Basica e Aplicada (UFOPA)Feitosa JM, Silva TSA, Xavier AEF, Rodrigues WCS, Silva ACE, Correa CVP, Aguiar FS, Mourao RHV, Oliveira EG, Nunes KM. "Evaluation of the quality of Amazonian butters as sustainable raw materials for applications in bioproducts." Rev Cienc Farm Basica Apl. 2021;42:e708. DOI 10.4322/2179-443X.0708. · document dated 2021 · read 2026-09-21

Table 2 (SAP, calculated iodine) and Table 3 (GC-MS fatty acids) for tucuma butter, plus discussion text (p.5) quoting the raw-material supplier's own spec range for lauric/myristic. Open-access PDF read in full.

Amazon Oil (producer)Tucuma (Astrocaryum vulgare) amendoa / Tucuma Butter technical/product page · read 2026-09-21

Producer page confirms CAS 98143-57-8 and 'Awara' as a regional synonym; describes the butter as similar to palm kernel butter with a higher melting point but gives no numeric SAP/iodine/fatty-acid/melting-point values.

Source is Feitosa et al. 2021 (Rev Cienc Farm Basica Apl, open access, read in full as a PDF) throughout, for a commercial tucuma (Astrocaryum vulgare Mart.) butter lot from Belem, Brazil. SAP (182.42 +/- 0.48 mg KOH/g, Table 2, direct titration) and iodine (2.78 g I2/100g) were both directly attributed to this study, BUT note the paper's methodology section states that for tucuma and ucuuba specifically (unlike murumuru/bacuri), iodine index was CALCULATED from the GC-MS fatty-acid profile via a standard formula (Instituto Adolfo Lutz method, using palmitoleic/oleic/linoleic/linolenic/gadoleic/erucic percentages), not measured by direct Wijs titration - flagging this per the clean-room rule on calculated-vs-measured values. Fatty acid composition is a hybrid: lauric (44-55%) and myristic (22-30%) are NOT this paper's own GC-MS result for their specific lot - they are the range from 'the supplier report' that Feitosa et al. quote in their discussion (p.5) as the comparison spec their tested lot failed to match. This supplier-quoted range was preferred as more representative because it aligns with other literature the paper cites (Pardauil et al., cited in Feitosa's ref 28: lauric 48%, myristic 25%, oleic 13.5% for tucuma kernel oil - NOT independently opened by me, known only via Feitosa's citation of it) and with general secondary literature indicating tucuma is lauric-dominant. Feitosa et al.'s OWN directly-measured GC-MS result for their specific lot was myristic-dominant and inverted: myristic 53.26%, lauric 19.63%, palmitic 6.94%, capric 1.46%, linoleic 1.48%, plus 5.80% 'elidic acid' (C18:1 trans-9, i.e. elaidic acid - a trans fat, excluded here as it has no matching schema key) and 4.05% labeled 'myristic acid derivate' (unclear identity, also excluded - no matching schema key). Palmitic/capric/linoleic values above ARE this paper's own direct GC-MS measurement (Table 3), since the supplier-quoted range did not cover those acids. A human merging this record should decide whether the supplier-range or Feitosa's own directly-measured (myristic-dominant) figures better represent the ingredient for this database - both are printed in the one document I opened. Unsaponifiable matter: not reported in Feitosa et al. 2021; a separate, unopened source (Pereira et al. 2019, Food Chem, cited as ref 11 in Feitosa et al. but not independently fetched by me) is mentioned in general web search summaries as reporting ~0.47% for tucuma kernel fat, but I could not verify this figure myself against the primary document, so it is left null rather than transcribed secondhand.

This record is part of the open ingredient database (ODbL). Found an error or a better primary source? The dataset is on GitHub; corrections with a document link are welcome.