Dabai (Canarium odontophyllum Miq.) is a fruit that is often eaten by first blanching in hot water to make the flesh creamier and softer, before it is served as a snack or side dish. In this study, Dabai fruit was blanched at different temperatures between 60 and 100 °C, with an increment of 10 °C, for up to 10 min, and the kinetics of quality changes (color and texture) were studied. Kinetic models that were assessed for changes of color and texture were zero-order, first-order, and fractional conversion model. The results showed that L parameter had no change throughout the blanching process, while parameters a*, b*, chroma (C), and total color difference (TCD) resulted as significantly increased as the temperature and duration of blanching increased. However, the change of firmness was not significant due to minor changes of firmness as the temperature and time increased. In terms of kinetic models, zero and fractional-conversion order well described the changes of a* parameter; while zero, first and fractional conversion well described parameters b*, C and TCD. Change of firmness did not fit with zero or first-order. All of the kinetic models obeyed the Arrhenius equation. Thus, the fitted kinetic models can be used to design the blanching process of Dabai fruit.

The Dabai fruit (Canarium odontophyllum Miq.) is seasonal in Sarawak. The flesh is often blanched in hot or lukewarm water to make it creamier and softer before being served as a snack or side dish. The fruit was blanched at temperatures ranging from 60°C to 100°C, with 10°C increments, for up to 10 minutes, whereby the quality changes in color and texture were investigated. Notably, the L parameter has remained unchanged during the blanching process, indicating that the dabai fruit’s dark color is retained. The parameters a*, b*, chroma (C), and total color difference (TCD), on the other hand, have increased significantly as the temperature and time of blanching are increased. However, the change in firmness was not substantial due to the slight variations in firmness as the temperature and time increased. From these findings, it can be inferred that the temperature and duration of blanching have significantly changed the dabai fruit’s color except for the firmness of the fruit. These findings would be useful in designing thermal processes and related calculations for the dabai fruit.

Blanching have been used as a thermal treatment in food processing especially as a pre-treatment of processes such as drying, freezing and canning that includes fruits and vegetables. Blanching treatment helps to remove the microorganisms, lengthen the shelf life and enhancing the color, flavor and texture of the fruits and vegetables. However, blanching affected the nutrients and characteristics of fruits and vegetables that contributes to the quality changes of the fruits and vegetables fruit. Thus, it is necessary to study about the quality changes during heat blanching of fruits and vegetables fruit to study the changes of the characteristics, nutrients and properties of the fruits and vegetables fruit. Kinetic modelling on the quality changes of fruits and vegetables fruit is crucial for quality modelling and quality control of fruits and vegetables fruit during the heat blanching treatment. Kinetic modelling is also important to identify which temperature and time that is optimum for the quality of fruits and vegetables after the heat blanching treatment, also to identify the kinetic trend of the properties of fruits and vegetables fruit that were affected. In this paper, general aspects of blanching process are discussed. Properties and methods to measure the quality changes were discussed. Models of kinetic according to the properties and characteristics affected by the blanching treatment were also reviewed. Keywords: fruits and vegetables; blanching; kinetic modelling; quality changes; thermal treatment