Logistic regression analysis of marketability of tomato fruit harvested at different maturity stages and subjected to disinfection, storage condition and storage period treatments

Abstract

This study was conducted to apply the logistic regression analysis to study the combined effects of continuous and categorical variables on the probability of marketability of tomato. Tomato fruits harvested at three maturity stages (green, pink, red) after pre-storage disinfections treatments (control, anolyte water, hot water, chlorinated water) were stored under evaporative cooler and ambient conditions for 28 days. Changes in the quality characteristics of the tomatoes were assessed every 7 days. Significant relationships were observed (p < 0.001) between the variables and probability of marketability of tomato. Nevertheless, some of the variables were not significant (p > 0.05) for the multiple logistic regression models. Combination of chlorinated water (Tr4), anolyte water (Tr2), green tomato (MS1) and evaporative cooler (SC2) showed high odds ratios. For instance, the odds of marketability of tomato for Tr4 was 27.501 times that of control (Tr1), for Tr2 it was 17.971 times that of Tr1, for MS1 it was 15.792 times that of red tomato (MS3) and for SC2 it was 3.271 times that of ambient storage over 28-day. This showed that Tr4 and Tr2 extended the marketability over a longer period, when compared to that of Tr1. The probability of the marketability of tomatoes was higher for tomatoes stored in the evaporative cooling environment. The model developed can be used by farmers and processors by measuring any of the convenient physical/chemical parameters (pH, TA, TSS, colour, texture) and apply the model to predict the marketability level for different storage periods.