Colour is an important attribute of any food product. Persimmon are noted for their intense orange to redcolouring and hence products marketed as made from persimmon are expected to inherit this attribute. Asthe persimmon fruit ripens the entire flesh of the fruit changes colour from a pale yellow-orange to a darkintense orange-red. This change is colour imparts changes in the colour qualities of a puree product. Theobjective of this research was to develop a model to enable colour prediction of a persimmon puree as afunction of the fruit maturity and puree strength. As a result a mathematical tool is created that enablesdesired colour properties of a puree product to be achieved by manipulating the strength of the puree. Colourdata for modelling was created with 3 sets of persimmon fruit of different maturities (firm, medium and soft)which were manipulated to 10 different solids concentrations ranging between half and double strengthsolids. Purees greater than single strength were created with the addition of freeze dried persimmon solids(source from the same persimmons), while lower than single strength purees were created with the dilution ofwater. Tristimulus CIELAB colour data was collected with a Minolta Spectrophotometer. Replicate 3 sets ofpersimmon puree were created and measured for model validation. The model was created to allowprediction the change in colour (L*, a*, b*, C or h) as a function of the change in strength of the puree. Assuch the raw data was converted to fraction change for both the solids (strength) and colour parameters.Converted data was fitted with empirical second order polynomial models that were applicable irrespective ofthe maturity of the fruit used to make the puree. The validation of the model revealed mean absolute errorsof prediction of less than 1.2 for all CIELAB parameters. The resulting model can be used to assess theimpact of puree strength manipulation on final product colour.
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