Midseason oranges for juice production

Abstract

Juice quality, yield performance, and cropping efficiency of 6 midseason orange varieties (Hamlin, Parramatta, Pineapple, Joppa, White Siletta, and Mediterranean Sweet), together with Seedless Valencia on 4 rootstocks [Troyer citrange, Poncirus trifoliata, rough lemon, and either Benton citrange (coastal) or sweet orange (inland)], were studied for their suitability for both processed and fresh orange juice production. Promising midseason varieties for processed orange juice were Parramatta and Hamlin on Troyer citrange, and Parramatta on P. trifoliata, when grown in coastal districts. Debittered juice of Joppa on Troyer citrange could also be used for processing by early September on the coast. Preferred inland varieties for production of processed orange juice were Mediterranean Sweet and Harnlin on Troyer citrange. Midseason oranges grown inland had higher citric acid levels than the same variety grown on the coast. This resulted in inland fruit having lower ratios of total soluble solids (TSS) to acid, and later maturities, than fruit grown on the coast. Acceptable fresh orange juice was produced from fruit of Parramatta, Hamlin, White Siletta, and Mediterranean Sweet varieties grown on Troyer citrange rootstock in coastal districts; inland, fruit of Mediterranean Sweet, Joppa, Parramatta, and White Siletta varieties on Troyer citrange rootstock produced good quality, fresh orange juice. Hamlin can also be marketed as fresh fruit. In coastal production areas, harvesting can commence from mid July for Hamlin, from mid to late August for Parramata, and from early September for White Siletta and Mediterranean Sweet. Harvest in inland districts for processed juice should commence in mid July for Hamlin and in early September for Mediterranean Sweet, whilst harvest for fresh juice and/or fruit should proceed in early September for Mediterranean Sweet, and in late September for Parramatta, White Siletta, and Joppa. Highest fruit yields and large trees were produced by Parramatta and Joppa on Troyer citrange and rough lemon rootstocks. Most quality characteristics were better for fruit produced on Troyer citrange than on rough lemon. Both Benton citrange and sweet orange performed poorly and are not recommended as rootstocks for midseason oranges. All varieties on Troyer citrange had better yield and TSS/ha than those on P. trifoliata rootstock, which produced smaller but highly cropping efficient trees.

Qualidade industrial e maturação de frutos de laranjeira "valência" sobre seis porta-enxertos

“…Por sua vez, Sarooshi & Hutton (1992) verifi caram que sete variedades de laranja, entre as quais 'Seedless Valencia', tiveram os maiores valores de rendimento de suco, em sete anos de avaliação, quando enxertadas em citrangeiro 'Troyer'.…”

Fruit yield of common orange varieties in south-east Australia: Initial evaluation versus long term performance

“…To address the fresh orange juice supply gap, and to reduce the impact of 'Valencia's other negative traits on citrus producers' profitability, local varieties originating as limb sports of 'Valencia' and a limited number of common orange varieties from overseas that had been in the country for some time have been evaluated (El-Zeftawi et al, 1985;Sarooshi and Hutton, 1992). However, a significant increase in the range of processing orange varieties available to the industry followed the removal in 1986 of an embargo on the importation of citrus planting material into Australia.…”