Effects of Chemical Pretreatments on Physiochemical and Drying Characteristics of Solar-Dried Tomato (Lycopersicon esculantum) Slices
M. Chapagain, P. Ojha, R. Karki, U. Subedi & M.B. Shrestha
The research was planned to study the impacts of chemical pre-treatments on physiochemical and drying attributes of solar-dried tomato (Var. Srijana) slices. Completely randomized Cut tomato slices were pretreated by plunging in solution of 0.2% Potassium metabisulphite (KMS), 1% calcium chloride (CaCl2), 3% sodium chloride (Nacl) and 0.2% KMS alongside 1% CaCl2 arrangement freely for 10 minutes which was then subjected to solar drying. Five Kilograms of tomato were used for each treatment and completely randomized design was used with five treatments including control (without any pre-treatment) and triplicate analysis. Acidity increased in pretreated items compared to control item aside from item pretreated with NaCl (4.42). Results demonstrated that KMS treated sample indicated higher maintenance of carotenoids (33.54mg/100g) and lycopene (16.21mg/100g) content whiloe vitamin C content was higher (34.65g/100 g) in sample pretreated with KMS+Cacl2. Non-enzymatic browning (NEB) was found to be increased in control sample (1.01) and least (0.51) in CaCl2 treatment. Here, rehydration proportion was most minimal for control item (0.22) with the high dehydration ratio of 16.47. From the microbial investigation, it was found that yeast and mould count was inside permissible farthest point (103-104 CFU/g) just for item pretreated with KMS, CaCl2 and KMS+CaCl2 from the investigation of drying curve, the drying pattern for all the artificially pretreated and untreated tomato cuts was observed to be same. It can be reasoned that pretreatments deliver considerable change in the quality of tomato.