Grape Chemistry as of 9/15/11

 

Varietal

Date

Sugar (Brix)

pH

Total Acidity (%)

Primitivo

       9-9-11*    

22.7

3.24

1.02

 

9-15-11

24.4

3.39

1.01

 

 

 

 

 

Barbera

9-15-11

23.2

3.04

1.53

 

 

 

 

 

Touriga Nacional (Quinta)

9-15-11

20.9

3.14

0.88

 *The values for 9-9-11 are the mean of two independent samples from the whole primitivo field.

Comments:  The primitivo showed nice progress in ripening in terms of brix and pH.  The relative lack of movement on TA may be related (we speculate) to the fact that we waited an extra day plus to analyze the 9-9-11 sample for TA, waiting for a reagent.  Potentially the acid level was not completely stable in the sample, resulting in a lower value than might have been obtained in a fresh sample.  In any event, we are very confident in the most recent TAs, all conducted on fresh juice samples.  The data suggest optimal harvest in 1-2 weeks, again depending on personal preferences and logistical considerations for individual clients.

The first barbera reading showed an expected high level of acid (and low pH), though not the most extreme we have seen for a first sample of the season.  More hang time is clearly needed, and the reasonable brix reading at this juncture gives us plenty of runway.  A mid-October harvest is still in reach.

The first touriga nacional sample (Quinta) showed lower brix than we expected, but the lowest TA of three varietals sampled.  We are targeting a Saturday harvest to accomodate all the Quinta shareholders, and though it’s too early to set this date based on the one data point, we would currently suggest no earlier than October 8, more likely October 15, and probably no later than October 22.