1. What dry matter measures
Fresh durian flesh contains water and solids such as carbohydrates, fats, proteins and minerals. As fruit develops on the tree, its solid fraction generally increases. Dry-matter testing adds quantitative evidence to maturity assessment rather than relying on appearance or experience alone.
In principle, a fresh flesh sample is weighed, dried by the prescribed method and weighed again. Dry-matter percentage equals dried mass divided by fresh mass, multiplied by 100. Actual testing should follow the responsible authority’s method and sampling protocol; one small piece should not be assumed to represent an entire orchard.
2. Minimums in Thailand’s TAS 3-2024
Thailand’s durian product standard sets variety-specific minimum dry-matter levels as part of determining suitable harvest maturity.
- Kradum Thong: at least 27% by mass
- Chanee: at least 30% by mass
- Puang Manee: at least 30% by mass
- Monthong: at least 32% by mass
- Kanyao: at least 32% by mass
3. Why pre-harvest testing matters in 2026
Thailand’s Department of Agricultural Extension incorporated harvest-opening dates and dry-matter checks into its 2026 eastern durian measures, framed as “test before harvest, organise orchards, produce safely.” The purpose is to prevent immature fruit from entering the market and protect buyer confidence.
An opening date is a seasonal management guide, not proof that every fruit in every orchard is ready. Weather, flower cohort, fruit position and orchard care create variation. Representative testing therefore checks the real condition more directly than counting days alone.
4. One number cannot define premium quality
Dry matter answers a maturity question. The eating experience also depends on variety, ripeness, aroma, texture, impact damage, temperature and transit time. A responsible quality record links test results with orchard or plot, harvest lot, selection date and ripening guidance.
For Siam Diamond, evidence before harvest makes the idea of source-level selection more concrete. This article does not claim that every individual product has been separately tested. Responsible communication means stating the criteria, process and limitations supported by actual records.
