Starch Grain
Definition
A storage carbohydrate granule produced by plants. Each major food plant species produces starch grains with a characteristic size, shape, and hilum (central pit) that are identifiable under polarised light microscopy even when the grain is partially degraded by amylase digestion.
- Origin
- Storage carbohydrate granule in plants
- Identifying features
- Size, shape, and hilum position
- Detection method
- Polarised light microscopy
- Use
- Stomach content and gastric plant matter analysis
Common questions
How can starch grains still be identified after digestion has begun?+
Amylase breaks starch down chemically but the granule's physical shape, size range, and hilum position degrade more slowly, so a partially digested grain can still be matched to a plant source under polarised light before it is fully broken down.
What does identifying starch grain species tell an investigator?+
It can indicate what plant-based foods the person last ate, which helps narrow a postmortem interval estimate when combined with digestion state, or corroborate an account of the deceased's last meal.
Related terms
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- Ingested Pollen
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- Sclerenchyma
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- Testa Fragment
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