Assessing grape loads at the winery for quality - how representative is the sampling?

摘要

Winemakers usually take samples from deliveries of grape loads at the receival area or weighbridge in order to measure the composition of the harvested fruit. The sample drawn is often subjected to chemical analyses and sometimes sensory assessment. The results of such assessments are very often used to make critical decisions about processing and in some cases even the probable end-use of grape loads. But how representative isrnthe sample itself? Before discussing that, it is worth remembering that all measurements (chemical compositional or otherwise) are subject to error and can include contributions of varying degree from sources including instrument, operator, random, and most importantly in the context of this article, error due to sampling.