Modeling Skin Injury from Hot Rice Porridge Spills

Abstract

The present work analyzes skin burns from spills of hot rice and milk products. The traditional Norwegian rice porridge serves as an example. By testing spills on objects emulating an arm, it was concluded that spills were seldom thinner than 3 mm, and stayed in place due to the viscosity of the porridge for more than one minute. The Pennes bioheat equation was solved numerically for such spills, including heat conduction to the skin and convective heat losses from the porridge surface. Temperatures were analyzed in the porridge and skin layers, and the resulting skin injury was calculated based on the basal layer temperature. Parameters influencing burn severity, such as porridge layer thickness, porridge temperature, removal of the porridge and thermal effects of post scald tempered (15 °C) water cooling were analyzed. The spilled porridge resulted in a prolonged heat supply to the skin, and the skin injury developed significantly with time. The porridge temperature turned out to be the most important injury parameter. A 70 °C porridge temperature could develop superficial partial-thickness burns. Porridge temperatures at processing temperatures nearly instantly developed severe burns. It was demonstrated that prompt removal of the hot porridge significantly reduced the injury development. The general advice is to avoid serving porridge and similar products at temperatures above 65 °C and, if spilled on the skin, to remove it quickly. After such scald incidents, it is advised to cool the injured area by tempered water for a prolonged period to stimulate healing.

Injury Threshold of Oral Contact with Hot Foods and Method for Its Sensory Evaluation

“…The results shown in Figure 8 for boiled potatoes are in good agreement with the results for hot rice porridge spills on skin [29]. Both material systems obviously have similar thermal properties.…”

“…The feeling of warmth on the hand, however, was similarly perceived to that on the tongue (data not shown)-so there does not seem to be much difference. This is confirmed by the fact that human skin pain receptors are located at approximately 0.1 mm depth [29].…”

“…For gases in free convection, they are between 3 and 30 W/(m 2 •K) [28]. Increasing the heat transfer coefficient between the free surface of the sample and the respiratory air to fictitious values up to 50 W/(m 2 •K) leads to faster cooling of the edge areas, the temperature profiles in the contact zone around x = 0 remain unchanged over a period of up to 10 s. According to Log [29], the heat transfer coefficient between the food sample and air was estimated to be 10 W/(m 2 •K). During short periods an increase of the heat transfer coefficient between the control volume and the surrounding skin tissue up to fictious values of 3000 W/(m 2 •K) has only a very small influence.…”

Ethanol and Methanol Burn Risks in the Home Environment

“…Assuming a flame temperature of 1500 K and a skin temperature of 310 K, this typically results in a convective heat flux of ≈30 kW/m 2 . Exposing naked skin to this heat flux quickly heats the skin surface, and the basal layer, to temperatures associated with burn injuries [ 35 ]. If combustible clothing textiles are exposed to flames of this heat flux or hit by burning liquid, the fabric is pilot-ignited almost instantaneously.…”