Preventing delayed ripening

Abstract

Preventing delayed ripening

Summary

Winegrape growers’ in warm regions have long struggled to ripen fruit early with the expectations of better quality. This study however shows that vineyard variability and seasonal weather conditions make it hard to determine specific causes for early ripening fruit or preventing the delayed ripening of fruit.

Scholefield Robinson Mildura were contracted to prepare and deliver a report which:

1. Investigated scientific literature reviewing factors that affected fruit ripening,
2. Conduct interviews with industry representatives to determine the sentiment about whether early ripening fruit was of better quality and thus produced better wine and the,
3. Analysis of benchmarking data

The scientific literature reported that excessive watering can delay harvest and that the rate of ripening is largely dependent on the number of actively photosynthesising leaves. The scientific literature however could not give any definitive answers with many papers reporting opposing results.

The interviews resulted in half the respondents indicating they believed that early ripening fruit improved quality however respondents had little evidence to prove these beliefs. The analysis of benchmarking data tied in with a Scholefield Robinson Mildura study to develop an indicator of winegrape quality. In the benchmarking data analysed it was shown that there was an “inconsistent relationship between harvest date and fruit quality” for a six year period.

The results of this project illustrated the strong influence that vineyard variability and seasonal weather conditions can have on the development and ripening of fruit and the potential quality of that fruit. Readers of this report and the attached report prepared by Scholefield Robinson Mildura should not conclude that the production of top quality fruit ripening early or delayed is not affected by the quality of their production techniques and should be left to chance but rather that some aspects of winegrape production require prediction and subsequent action.