Starch analysis

Starch analysis or starch grain analysis is a technique that is useful in archaeological research to determine plant taxa. In certain samples of food plants, spices, drugs and desiccated archaeological plant matter, the histological elements can survive and thus be identified but in other samples, like carbonized (burnt) or older materials this is extremely difficult. However starch grains are much more hardy. The technique relies on the fact that a researcher can analyze or microscopically observe starch grains found on artifacts or in soils. Starch grains, ubiquitous in plants, have individual characteristics and resistance to grinding and drying and even to light burning so they are often preserved when other plant remains are lost - thus providing an additional tool to understand the past use of plants. Starch analysis or starch grain analysis is a technique that is useful in archaeological research to determine plant taxa. In certain samples of food plants, spices, drugs and desiccated archaeological plant matter, the histological elements can survive and thus be identified but in other samples, like carbonized (burnt) or older materials this is extremely difficult. However starch grains are much more hardy. The technique relies on the fact that a researcher can analyze or microscopically observe starch grains found on artifacts or in soils. Starch grains, ubiquitous in plants, have individual characteristics and resistance to grinding and drying and even to light burning so they are often preserved when other plant remains are lost - thus providing an additional tool to understand the past use of plants. Starch grain analysis is not a perfect science, however, plant starch grain analysis is a diagnostic feature of multiple applications according to the peculiarities and to the origin of the plant material.The size, shape and structure of grains from plant species, varies little, which can lead to identification. Starch grains have been removed and identified from stone tools, ceramic sherds, organic materials, dental calculus, and sediments and animal remains to determine diet and when humans began to exploit wild food varieties. In some cases the grains can become degraded. Factors such as heat and water absorption may affect the structure of the grains, making identification more difficult. Even if the remains are well preserved, water logging, dehydration, desiccation or damage from fungi can destroy the starch. In some cases, even within the same species, starch grains can differ in shape and size and the size of the grain affects its survivability in the archaeological record. Starch is produced in plants as a form of energy storage through the process of photosynthesis. When the plant is in need of energy, the stored starch is converted back into glucose.