Color Measurement Methods for Optimization of Oven Operation (Baking of Sliced Bread with Superheated Steam and Hot Air)

Abstract

An in-situ color measurement method during heating in an oven is required for optimizing the oven cooking operation. However, conventional colorimetric apparatus is not applicable because such processes usually involve high temperatures and wet surfaces. In this study, we equip an oven chamber with optical fibers connected to a halogen light and spectrometer to perform the in-situ (real time) color measurement. To demonstrate the usability of this method, we observed the color change in white bread heated by hot air and superheated steam at 200℃ as a trial experiment, and compared results from two other types of colorimetric measurements of the samples after heating: a color image recording system using a digital camera, and a commercial spectrophotometer. We found that the value of L* decreased more quickly, and b* had a lower value for baking by superheated steam in comparison with baking by hot air at the same temperature.

Superheated steam processing of cereals and cereal products: A review

“…SS drying has a more significant effect on food color than hot air drying. After SS drying or baking, the color of foods becomes darker than that using hot air drying (Iyota et al., 2013; Jittanit & Angkaew, 2020; Markowski et al., 2003; Swasdisevi et al., 2013; Taechapairoj et al., 2003; Taweerattanapanish et al., 1999), which is mainly due to the condensation of SS on the cereal surface and the diffusion of particular substances with color pigments from the cereal surface to the endosperm during SS processing (Jittanit & Angkaew, 2020; Taechapairoj et al., 2003). The condensed water can promote the migration of reducing sugars and amino acids, which are the materials required for the Maillard reactions (Jittanit & Angkaew, 2020).…”