Effect of surface coating on the quality of minimally processed red chillies (Capsicum annum) stored at low temperature

Fresh red chillies are used a great deal in our local dishes. One of the popular usages is for garnishing, usually in the form of thin slices. However, the major problem is to avoid excessive water loss due to transpiration that may cause shrinkage, softening and pathological disorders that severely reduced the quality and acceptability of this minimally processed (MP) chillies. Therefore, this study is aimed at determining the effect of surface coating on the quality and shelf life of the MP chillies. Red chillies (Capsicum annuum), variety Kulai of commercial maturity were dipped into 1% sodium hypochlorite solution for 5 minutes and rinsed three times with deionized water. Then, chillies were minimally processed and dipped in surface coating solution namely carboxylmethylcellulose (CMC) at a concentration of 0.5% (Treatment A), 1.0% (Treatment B) and distilled water (Treatment C) as control. After the treatment, approximately 100gm of the samples were placed on polystrene plate J-2 and packaged with low density polyethylene (LDPE) film followed by storage at 5 (+-) 1C75-90% R.H. Physico-chemical characteristics were studied colour, texture, titratable acidity, ascorbic acid content, pH, total soluble solids, percentage water loss and capsaicin and dihydrocapsaicin content. Data obtained were analysed using statistical analysis system (SAS) program and LSD at 5% level. Red chili slices that were treated with 1.0% CMC gava the best result for reduction of water loss. There was no significant difference in visual colour, titrable acidity and texture of minimally processed red chillies stored at low temperature between the treated samples and control. The pH values and total soluble solids were significantly (p0.05) different between the control and all the treated samples. However, there was no significant difference found between minimally processed red chillies treated in the different concentration of CMC. There were no significant difference observed in the capsaicin and dihydrocapsaicin contents between control abd CMC dipped minimally processed red chillies. However, there was a significant (p0.05) in both capsaicin and dihydrocapsaicin contents from day 0 to day 8 and later decreased after day 12.