Processing quality of oranges grown in the near north coast area of Queensland

Abstract

A study was made of the influence on processing quality of variety, rootstock, time of picking, seasonal meteorological conditions, farm practices and district. Joppas were fairly comparable with Valencias in most aspects of processing quality. Fruit from trees on trifoliate orange and sweet orange rootstocks was superior in processing quality to that from trees on rough lemon rootstock. Processing quality improved throughout the harvesting season. Substantial seasonal variation was noted in some processing quality characteristics. There were large differences between farms within the Palmwoods district in all characteristics studied. Correlations between tree age, fruit size and some internal quality characteristics were established. Fruit grown in the Elimbah-Beerwah district was larger and lower in soluble constituents than that grown in the Palmwoods-Maroochy district. Processing quality was inferior to that of Florida oranges and only a small percentage of the fruit would satisfy the minimum requirements for oranges for processing laid down by Florida processors.