GIFSQ Tools · Module 2 — Food Chemistry & Physicochemical Testing · Tool 27 of 500
Work out how much invert sugar forms when the sucrose in a sample hydrolyses, and the total sugars expressed as invert sugar. AOAC 923.09.
Try sample values — fills the form with the worked example below.
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Invert sugar formed (%)
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Total sugars as invert (%)
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Sucrose (%)
Equation: Invert sugar formed % = sucrose % × 1.0526. Total sugars as invert % = reducing sugar % + invert sugar formed %.
Method: AOAC 923.09 (Lane-Eynon) — sucrose hydrolyses to equal parts glucose and fructose. The factor 1.0526 is 360.3 ÷ 342.3: one sucrose molecule (342.3) gains a water molecule on hydrolysis and becomes glucose plus fructose (360.3 together), so the invert sugar weighs 5.26 % more than the sucrose it came from.
Assumptions: all of the sucrose is inverted; the reducing-sugar figure already holds the free glucose and fructose in the sample.
Limitations: this is a calculated value, not a direct measurement — it does not measure invert sugar in the sample. Other sugars present are not separated out.
Rounding: results to 2 decimal places.
This is a calculation aid, not a laboratory report — confirm against your accredited method before citing a value.
Method: AOAC 923.09 (Lane-Eynon) — sucrose hydrolyses to equal parts glucose and fructose. The factor 1.0526 is 360.3 ÷ 342.3: one sucrose molecule (342.3) gains a water molecule on hydrolysis and becomes glucose plus fructose (360.3 together), so the invert sugar weighs 5.26 % more than the sucrose it came from.
Assumptions: all of the sucrose is inverted; the reducing-sugar figure already holds the free glucose and fructose in the sample.
Limitations: this is a calculated value, not a direct measurement — it does not measure invert sugar in the sample. Other sugars present are not separated out.
Rounding: results to 2 decimal places.
This is a calculation aid, not a laboratory report — confirm against your accredited method before citing a value.
Worked example: A syrup holds 40.00 % sucrose and 5.00 % reducing sugar. Invert sugar formed = 40.00 × 1.0526 = 42.10 %; total sugars as invert = 5.00 + 42.10 = 47.10 %.
Enter values above to see results.
Typical invert sugar: honey 70–80 % (mostly formed in the hive), golden syrup 40–50 %, jam 15–25 % after boiling with acid. Sucrose × 0.95 gives the sucrose figure back from an invert-sugar result (Tool 26). Tool 27 of 500 — GIFSQ
