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Midwest Grape and Wine Industry Institute

​​​​​​Bugging out in the vineyard: Getting to the root of phylloxera management in Victoria, Australia​​

Maureen Moroney, Dr. Aude Watrelot | Nov 2, 2021

The focus of the case study is on choosing the type of wine grape vines to plant in a newly-established vineyard, with the option of either Vitis vinifera scion material grafted onto phylloxera-resistant rootstock or own-rooted phylloxera-resistant non-Vinifera grape cultivars. The case discusses long-term planting decisions, high investment risk, a lack of effective pesticides and biological control options, mechanisms of phylloxera spread, origins of grapevine resistance, grafting options, labor inputs, and impacts on grape and wine quality and marketability.

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Midwest Fruit and Pest Management Guide 2021-2022

Joe Hannan, Et. al | 2021

This guide provides conventional pest management recommendations for commercial tree fruit, small fruit, and grape producers throughout the Midwest and surrounding states. These recommendations have been formulated to provide up-to-date information on pesticides and their application.

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Estimating Grape Maturity by Total Soluble Solids

Dr. Aude Watrelot, Jennie Savits, & Maureen Moroney | 2020

The harvest parameter of total soluble solids (TSS) is a measure of the density (mass/volume) of all soluble solids. A component in determining ripeness of the berries is the concentration of sugars. This determines the potential alcohol content achievable during fermentation through yeasts consumption of sugars.

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Estimating Grape Maturity by Sensory Analysis

Dr. Aude Watrelot, Jennie Savits, & Maureen Moroney | 2020

To estimate grape harvest maturity, technological parameters including total soluble solids or °Brix, pH and titratable acidity are commonly measured. In addition to the increase of °Brix and pH and the decrease of titratable acidity during berry ripening, qualitative parameters can be used to evaluate the right time to harvest. The qualitative parameters are skin tannins, seed color, berry detachment, and berry aroma and flavors. Evaluation of these parameters involve four senses: taste, visual, touch and smell.

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Estimating Grape Maturity by Titratable Acidity

Dr. Aude Watrelot, Jennie Savits, & Maureen Moroney | 2020

This publication will show how to measure titratable acidity in wine samples. Titratable acidity is a measurement that approximates total acidity in must and wine, and is indicative of the sensory perception of tartness. TA measures both the dissociated and un-dissociated acids neutralized by a base. A solid understanding of the organic acid composition of the must is very important for the winemaker to: Determine the harvest time and wine style, decide on any must treatments prior to fermentation, monitor the stability of a wine, and comply to minimum and maximum acid level regulations set by the TTB.

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