The storage stability of passionfruit concentrate

Passionfruit (Passiflora edulis) concentrates (542 g/kg soluble solids) prepared in a wiped-film evaporator were stored for up to 6 months at - 18°, 4° and 20°C. Yeast and mould counts were taken and colour changes noted during storage. When suitable diluted concentrate colour and flavour were acceptable for 1 month at 20°C, 3 months at 4°C and 6 months at -18°C. Commercial short-term storage of concentrate at temperatures above -18°C appears to be feasible. An address presented to the 20th Annual Convention AIFST, Albury NSW, 16th- 20th May, 1987

Passionfruit growing guide - Second edition

This edition of 'The passionfruit growing guide' is a substantial update of the first edition, which was published in 2006. Each chapter deals with a specific aspect of the development and management of a passionfruit plantation. This guide is intended for use by prospective, new and established growers and addresses all aspects of passionfruit growing, from site selection and planning through to harvesting and marketing the fruit. It provides practical advice and propogation, fertilising, irrigation, and pest disease and control. Also, it includes information on varieties of passionfruit, financial budgets, chemicals registered for use on passionfruit and useful contacts.

Fruit fly host status testing of a new passionfruit cultivar

Fruit fly host status testing of a new passionfruit cultivar.

Efficient organogenesis of an Australian passionfruit hybrid (Passiflora edulis x Passiflora edulis var. flavicarpa) suitable for gene delivery

An efficient regeneration protocol based on organogenesis from cotyledon explants and suitable for gene delivery has been developed for an Australian passionfruit hybrid. Multiple shoots were regenerated from 30-day-old cotyledon explants on Murashige and Skoog (MS) medium containing 6-benzylvaminopurine (BAP) and coconut water. Media pulsing experiments were conducted to investigate the effect on organogenesis of exposure time of the explants to MS containing 10 mu M BAP and 10% (v/v) coconut water, i.e. passionfruit regeneration medium (PRM). Continuous exposure of these explants to PRM maximised the number of shoots produced to 12.1 per explant. However, periods on hormone-free medium improved the appearance of the shoots and increased the number of explants with shoots from 75 to 84.6%. Further, shoots exposed for 7 days to half-strength MS supplemented with 10 mu M NAA (1-napthalene acetic acid) produced twice as many plantlets than those on half-strength MS alone. Transient GUS histochemical assays indicated delivery of the uidA gene via Agrobacterium tumefaciens.

Efficacy of acibenzolar-S-methyl (Bion®) treatment of Australian commercial passionfruit, Passiflora edulis f. sp. flavicarpa, on resistance to Passionfruit woodiness virus (PWV) and activities of chitinase & β-1,3-glucanase

This greenhouse study investigated the efficacy of acibenzolar-S-methyl (Bion®) treatment of lower leaves of passionfruit, (Passiflora edulis f. sp. flavicarpa), on Passionfruit woodiness disease and activities of two pathogenesis-related proteins, chitinase and β-1,3-glucanase after inoculation with passionfruit woodiness virus (PWV). All Bion® concentrations reduced disease symptoms, but the concentration of 0.025 g active ingredient (a.i.)/l was the most effective, reducing disease severity in systemic leaves by 23, 29 and 30 compared with water-treated controls at 30, 40 and 50 days post inoculation (dpi) with PWV, respectively. Correspondingly, relative virus concentration as determined by DAS-ELISA in the upper, untreated leaves (new growth) above the site of inoculation at 50 dpi was reduced by 17 and 22 in plants treated with 0.025 and 0.05 g a.i./l, respectively. Bion® treatment and subsequent inoculation with PWV increased chitinase and β-1,3-glucanase activities in the new leaves above the site of inoculation at 30 dpi with PWV. It was concluded that optimal protective Bion® treatment concentrations were 0.025 and 0.05 g a.i./l.

Aseptic Packaging of Tropical Fruit Purees

The object of this investigation was to develop high quality aseptically packaged mango and passionfruit puree products. Kensington mango puree (acidified to ph 3.5) and deseeded passionfruit pulp (ph 3.0) were sterilised in a scraped-surface heat exchanger, cooled to 20°C in a tubular heat-exchanger, aseptically packaged in sterile laminate bags. Six sterilising time/temperature combinations were compared - 85°C/15 secs, 85°C/60 secs, 90° C/15 secs, 90°/60 secs, 95°C/15 secs, 95°C/60 secs. Products were assessed immediately after processing, and after eight months ambient storage, for microbial, physical, chemical, and sensory quality. All treatments were microbiologically sound and showed no enzyme activity. Sensory quality was very acceptable, and there was no evidence of heat damage. Quality (especially colour and flavour) decreased during storage in all heat treatments.