Enhancing shelf life of tomato under controlled atmosphere condition using diffusion channel system

Abstract

Experiments were conducted to extend the shelf-life of tomato using diffusion channel system. Diffusion channels of different combination in length (60, 120, 180, 240 mm) and diameter (3, 6, 9, 12 mm) were installed in the storage chambers of 2L capacity. Tomato samples (800 ± 15 g) at breaker stage were taken in the chambers and stored at 10 °C, 20 °C and 30 °C. Gas concentrations in the chambers were measured periodically untill the end of storage period. O₂ concentration decreased and CO₂ concentration increased with increase in channel length and become more distinct as the diameter increased. These channels were maintained the O₂ concentration in the ranges between 7.2% and 15.5% and CO₂ was 5.2% and 16.3% in the storage chambers. Respiration rate (RR) of tomato decreased with increase in channel length and increased with diameter. The RR of 1.95–8.36, 2.52 to 11.43 and 4.21–14.32 mg O₂/kg h was sustained at 10 °C, 20 °C and 30 °C respectively irrespective of channel length and diameter. Temperature, channel length and diameter had a significant (P ≤ 0.05) effect on visual quality index, firmness, ascorbic acid and lycopene and no significant difference on titratable acidity, total soluble solids and total sugars. The colour change was directly related to lycopene formation. Tomato was stored for 40 days at 10 °C, 32 days at 20 °C and 23 days at 30 °C under diffusion channel combination of length 180 mm and diameter 9 mm with good colour, texture, fresh appearance, retained nutritional values and good marketability conditions.