Early harvest delays berry skin browning of ‘Princess’ table grapes

Table grapes commonly suffer from tissue browning during harvest, pack- ing, storage and shelf life, resulting in lower prices and reduced access to markets. We evaluated the develop- ment of browning symptoms in 'Prin- cess' table grapes. The berries had high skin browning but very low flesh browning incidences. The most skin browning was found in highly mature grapes and appeared after 3 weeks of cold storage. Skin browning was directly related to fruit maturity, but vineyard location had a greater im- pact on the incidence of skin brown- ing than maturity. In all locations, the skin browning susceptibility of 'Prin- cess' table grapes rapidly increased when the berries reached a titratable acidity of less than or equal to 0.60% and/or a soluble solids concentration greater than or equal to 18.0%. Based on this work, we recommend harvest- ing 'Princess' at a soluble solids con- centration between 16.0% and 18.0%.