GIFSQ Tools · Module 1 — Food Composition & Proximate Analysis · Tool 1 of 500
Oven-drying method. Enter the sample weight before and after drying to get moisture on a wet and dry basis, plus dry matter.
Try sample values — fills the form with the worked example below.
Replicates (optional — mean & standard deviation)
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Moisture, wet basis (%)
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Moisture, dry basis (%)
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Dry matter (%)
Equation: Moisture % (wet basis) = (mwet − mdry) ÷ mwet × 100
Moisture % (dry basis) = (mwet − mdry) ÷ mdry × 100 · Dry matter % = 100 − Moisture % (wet basis)
Method: Oven drying to constant weight, AOAC 925.10 / ISO 1442 (105 °C).
Assumptions: all mass lost on drying is water; no volatile compounds lost; sample dried to constant weight.
Limitations: volatile substances other than water inflate the result; very hygroscopic samples reabsorb moisture while weighing; the method does not distinguish bound from free water.
Rounding: results to 2 decimal places; intermediate values are not rounded. Replicate SD is the sample SD (÷ n−1).
This is a calculation aid, not a laboratory report — confirm against your accredited method before citing a value.
Moisture % (dry basis) = (mwet − mdry) ÷ mdry × 100 · Dry matter % = 100 − Moisture % (wet basis)
Method: Oven drying to constant weight, AOAC 925.10 / ISO 1442 (105 °C).
Assumptions: all mass lost on drying is water; no volatile compounds lost; sample dried to constant weight.
Limitations: volatile substances other than water inflate the result; very hygroscopic samples reabsorb moisture while weighing; the method does not distinguish bound from free water.
Rounding: results to 2 decimal places; intermediate values are not rounded. Replicate SD is the sample SD (÷ n−1).
This is a calculation aid, not a laboratory report — confirm against your accredited method before citing a value.
Worked example: 5.000 g flour dried to 4.350 g. Loss = 0.650 g. Moisture (wet basis) = 0.650 ÷ 5.000 × 100 = 13.00 %; moisture (dry basis) = 0.650 ÷ 4.350 × 100 = 14.94 %; dry matter = 87.00 %. Replicates 13.0, 13.2, 12.9 % give mean 13.03 % ± SD 0.15 %.
Enter values above to see results.
Typical moisture: flour 12–14 %, milk powder 2–4 %, fresh meat 60–75 %. If the dry weight is equal to or greater than the wet weight, check the balance reading and the drying step — the result cannot be zero or negative moisture. Tool 1 of 500 — GIFSQ
