FFA Titration Calculator

How the calculation works

Free fatty acid is the share of fatty acids that have left the triglyceride. In a laboratory it is measured by dissolving a weighed sample in a neutral solvent and titrating the acidity with standardised sodium or potassium hydroxide. The familiar oils-and-fats expression is FFA (% as the reference acid) = (V × N × M) / (10 × W), where V is the titrant volume in millilitres, N is the normality in moles per litre, M is the molecular weight of the reference fatty acid in grams per mole, and W is the sample mass in grams.

With oleic acid (M = 282.46) this simplifies to the factor used throughout the shea trade: FFA % as oleic acid = 28.2 × titre (mL) × normality ÷ sample weight (g). Palmitic acid (256.42) gives 25.6; lauric acid (200.32) gives 20.0. Shea butter is reported as oleic unless a buyer specifies otherwise. Palm oil is often reported as palmitic; coconut and palm-kernel oils as lauric. The calculator also accepts a custom molecular weight when a method names a different acid.

Acid value (mg KOH per gram of fat) uses the molecular weight of potassium hydroxide: AV = (V × N × 56.1) / W. Because 56.1 ÷ 28.2 is about 1.99, acid value is approximately FFA as oleic multiplied by 1.99. The tool reports both the titration acid value and that conversion so a certificate that prints only one of the two can still be compared. Normality is what matters, not whether the burette holds NaOH or KOH: a standardised strong base of known normality is valid. ISO 660 is commonly written for KOH; AOCS Ca 5a-40 is often taught with NaOH.

The meaning of a given FFA is on the free fatty acid specification. FFA in unrefined shea is set by kernel handling before pressing, not by filtration afterwards.

Assumptions and limits

The arithmetic assumes a standardised titrant whose normality is known to three decimals, a blank-corrected titre, complete dissolution of the fat, and a phenolphthalein endpoint held as a faint pink for thirty seconds. Dark-coloured unrefined shea can hide that colour change; a potentiometric endpoint or an alternative indicator is then more honest than forcing a visual pink. The calculator is not a substitute for the full AOCS or ISO procedure — solvent choice, heating, and carbon-dioxide exclusion all sit outside the formula.

Results are shown to two decimal places. Duplicate titrations on the same sample should agree closely; a wide split is a method problem, not a rounding problem. The tool does not upload readings and does not store lot identifiers. Defaults of 0.1 N and 5 g are labelled as typical laboratory starting points so they are never mistaken for EMI laboratory settings.

What your result means for shea butter

Against published ECOWAS bands for unrefined shea, FFA at or below 1 % as oleic is Grade 1 (often called Grade A in the trade); 1–3 % is Grade 2 (Grade B); 3–8 % is Grade 3 (Grade C); above 8 % sits outside those three bands. Those ceilings are published regional / literature bands — not EMI QC limits. The COA governs.

A single FFA does not grade a lot on its own. Peroxide value and moisture must be read with it, which is why the shea butter grade checker and the COA interpreter exist. The trade names Grade A, B and C are explained on shea butter grades. Unrefined Grade A supply is described on the Grade A product page. Above about 3 % FFA, estimate the alkali a refiner would need with the caustic soda dose calculator.