Laetitia Porgès

Fruit and juice quality of several grape cultivars and distribution of the grapes on the vinestocks

The work carried out by Laetitia Porgès as part of the laboratory’s vineyard project consists in analysing the must quality of grapes sampled during the 2000 harvest on the Frelighsburg Experimental Farm, and assessing the distribution of the grape crop.
A three-part qualitative analysis will be carried out on each sample:

1. total acidity
2. soluble solids (refractometer)
3. colour (Pantone-type scale).

The results of the analysis will be used to estimate grape maturity dates for each grape cultivar.
The second stage takes place in the field: a distribution scale has been defined (from 0 for no clusters to 3 for most of crop), and each vinestock is scored at five levels (from ground level to the top). Producers are very keen to have the findings of this research because the farther apart the grapes are, the more labour is required to harvest them.

Data collection is under way, more than 200 samples from three sampling dates have already been analysed, and field observations are almost over. The study is expected to be completed by the end of August.

Laetitia Porgès
Student at L'Institut National d'Horticulture
2, rue Le Nôtre
49045 ANGERS

The persons in charge of the training course: Shahrokh Khanizadeh & Johanne Cousineau