Food holder temperature maintenance system

Abstract

A food holder arrangement is disclosed for use in delivering meals including both hot and cold food items to points of consumption remote from the point of preparation with the hot and cold food temperatures maintained. The food holder arrangement includes a flat tray having a heat retaining insert extending over a portion of the area of the tray. A pair of covers are also provided, one extending over the area occupied by the heat retaining insert, the other extending over a remaining area of the tray, with this other cover having in its top a heat absorbing insert. This location of the respective inserts is such that upon preheating and prechilling of the inserts, convection currents result within the respective covers which are augmented by conductive and radiation heat transfer effects so as to maintain the hot and cold food temperatures. These inserts are disclosed as either materials having a high heat capacity or substances which have an appropriate phase change at the approximate food temperatures which are to be maintained. Also disclosed is an improved insert arrangement for maintaining the hot foods at relatively level, moderately hot temperatures, the insert including a non-toxic substance which undergoes a change of state at temperatures on the order of 125.degree.-200.degree. F. so that the heat released in undergoing such change of state may be utilized to maintain the food temperatures. Examples of such substances are given as waxy organic crystalline substances such as paraffin, stearic acid, and palmitic acid or mixtures of the same.