ABSTRACT
Climatic conditions in retail stores are very poor for most perishables. The primary problem is the high water loss because of the tremendous water vapor partial pressure difference between the produce surface and the surrounding air. In addition, high temperatures in retail stores accelerate decomposition.
In preliminary experiments with a laboratory display cabinet combined with an ultrasonic humidifier, water loss of butterhead lettuce were reduced by as much as 80%. The vegetable surface stayed visibly dry.
Based on the results of these experiments, an investigation of three food display cabinets were carried out under retail conditions. One of the cabinets was used as a reference and had no cooling and humidification capability. The two other cabinets were modified using ultrasonic humidifiers with and without cooling.
Relative humidity in both humidified cabinets was similar, i.e., about 20% to 30% higher than in the control cabinet. The water loss, measured by small bowls with wet fleece was reduced in all cases by more than 50 %. The keeping quality of small radishes, measured by external and internal quality parameters, clearly increased for both tested versions of the display cabinets.
