Abstract:
Cavendish is the widely grown banana cultivar in the world today and the most prominent
cultivar in the international trade. Crown rot, one of the most drastic postharvest diseases of
Cavendish banana can cause severe postharvest loss both in the local and export markets. In the
industry, cut crowns of banana are treated with fungicides to control this disease. Due to
hazardous effects of fungicides, finding suitable alternatives in the management of crown rot of
banana is essential. In this study, effect of alum (potassium aluminium sulphate) in combination
with vacuum packaging was investigated in controlling crown rot disease and extending the
shelf life of Cavendish banana at cold storage.
Twelve week mature Cavendish banana (Musa acuminata, AAA, Grande Naine cultivar) hands
were treated with 1% (w/v) alum or distilled water (controlled). Treated and control fruits were
packed in Low density polyethylene bags, air inside bags were removed using vacuum and
placed in fiber board cartons and stored in a cold room at 12-14 ºC. Each treatment comprised
10 replicate boxes each with 5 hands. In-package gases were analyzed after 14 days of cold
storage. Physicochemical properties (pH, TSS, TA and firmness), sensory properties (peel
colour, flesh colour, aroma, flavour, taste and overall acceptability) and crown rot disease
severity were determined in ripening induced fruits. Test marketing trials were conducted at
CIC fruit outlet in Dambulla, Sri Lanka where treated fruits were provided to consumers and
staff to obtain feedback on the quality of treated banana.
At the end of 14 days, O2 in packages remained between 5.0 to 5.8% while CO2% ranged from
4.9% to 5.8%. Alum in combination with vacuum packaging significantly controlled crown rot
disease of Cavendish banana compared to the control. Physicochemical and sensory properties
were unaffected by alum + vacuum packaging treatment when compared to control. Treated
banana obtained higher score values from the customers and staff of fruit outlets for the sensory
properties compared to the control. Therefore, this eco-friendly treatment strategy could be
recommended in preparing Cavendish banana for local market as well as commercial scale
export to various destinations which require a transit time of two weeks.