Morphological identification of selected spices by starches, calciphytoliths, and phytoliths

Abstract

Spices have played a crucial role in shaping human culture and facilitating trade across civilizations. Despite their significance, identifying spices in archaeological contexts remains challenging due to the poor preservation of plant remains. This limitation has hindered our understanding of their historical use and distribution. Here, we used a polarizing microscope to analyze the presence and morphological characteristics of starches, calciphytoliths (calcium oxalate crystals), and phytoliths in 23 different spices. Our analysis revealed that all samples contained at least one type of microfossil, with 11 spices identifiable by starches, 10 by calciphytoliths, and 2 by phytoliths. Notably, Nutmeg (Myristica fragrans), Amomum Fruit (Amomum tsaoko), Kencur (Kaempferia galanga), and Ginger (Zingiber officinale) were identified with higher confidence due to the presence of two or more diagnostic microfossils. This study establishes identification criteria for 18 spices and provides a valuable tool for reconstructing the history of spice use and trade, particularly in regions with poor plant preservation, contributing to a deeper understanding of prehistoric cultural and trade networks.