What's New

Commercial Ice Cream Display Lighting in Freezer Merchandisers

When commercial ice cream displays are exposed to the fluorescent lighting commonly found in freezer dairy merchandisers, ice crystals can form, and the light initiates two chemical reactions which result in off-flavors.

Promolux Safe Spectrum lamps emit lower levels of heat and ultraviolet radiation than regular fluorescent lamps, thus reducing the rate of these chemical reactions in ice cream.

For dairy science references and excerpts click here.

Lipid Oxidation From Ice Cream Merchandiser Lighting

When ice cream is exposed to sunlight or to the fluorescent lighting commonly found in frozen dairy display cases, the light initiates two chemical reactions which result in off-flavors and the loss of nutrients.

First, whey proteins composed of amino acids containing sulfur degrade and break down, producing “sunlight” flavors reminiscent of burnt feathers or burnt hair that can last for two to three days.

In the second reaction, the unsaturated fatty acids in milk lipids (milk fat triglycerides / triacylglycerols) become oxidized, producing malodorous carbonyl compounds that taste metallic or cardboardy and do not dissipate.

Ice cream tends to have a high fat content, making it particularly vulnerable to strong supermarket lighting and the off-flavor effects of lipid oxidation. In one study, vanilla ice cream that had been stored directly under high-intensity lighting turned rancid, developing high levels of dimethyl disulfide and hexanal, two indicators that the ice cream had been damaged by light.

Promolux Safe Spectrum lamps emit lower levels of heat and ultraviolet radiation than regular fluorescent lamps, thus reducing the rate of these chemical reactions in ice cream. Compared to other fluorescent lighting, Promolux lamps emit 86% lower UV B radiation, a shorter wavelength that penetrates and causes heating, and 52% lower UV A radiation, a longer wavelength that tends to affect surfaces.

[Top]

Ice Cream Flavor Changes in Retail Ice Cream Showcases

Factors that affect the rate of lipid oxidation in ice cream are the intensity of the light, the wavelengths present in the light, the distance between the fluorescent light bulb and the ice cream, the material of the container, the amount of surface area exposed to the light, the temperature of the ice cream, the fat content of the ice cream, and the duration of light exposure.

Ice cream in light-transmissible plastic containers is most vulnerable but ice cream in paper cartons can also be affected when the cartons are exposed to intense light for long periods of time.

Since Promolux lamps minimize the emission of damaging visible spectrum and UV wavelengths, using Promolux lamps will minimize these flavor changes in ice cream.

[Top]

Ice Crystal Formation in Supermarket Ice Cream

UV radiation easily penetrates cold atmospheres and creates heat at the surface of frozen packages. Heat and radiation from regular supermarket fluorescent lighting can cause the top surface of ice cream to melt, separating the water in the ice cream from the other ingredients. When this water refreezes, ice crystals form within the ice cream.

Ice cream can also become discolored when exposed to light. Ice crystal formation and discoloration can also happen with ice cream cakes, especially when these are stored in cardboard boxes with transparent tops. If the ice cream cake is decorated, the wrong lighting can cause white decorations or icing to appear yellow, and red decorations will seem dull.

Promolux lamps emit a more balanced range of wavelengths, including more of the red and blue wavelengths and more moderate levels of the damaging yellow and green wavelengths than regular fluorescent lighting, reducing ice crystal formation and revealing the bright colors of decorations.

[Top]

Promolux True Color Definition Lamps

Promolux Safe Spectrum balanced full spectrum lamps emit lower levels of heat and ultraviolet radiation than regular supermarket fluorescent lamps, thus reducing the rate of damaging chemical reactions in milk and dairy products. Compared to other fluorescent lighting, Promolux lamps emit 86% lower UV B radiation, a shorter wavelength that penetrates and causes heating, and 52% lower UV A radiation, a longer wavelength that tends to affect surfaces.

Because Promolux lamps are designed for true color definition, they have a more balanced visible spectrum than other fluorescent lamps. The yellow and green wavelengths that are predominant in regular fluorescent lighting are the most damaging wavelengths in the visible spectrum. Promolux lamps emit a more balanced range of wavelengths, including more of the red and blue wavelengths and more moderate levels of the yellow and green wavelengths. It is impossible to create a natural light that does not have any yellow or green wavelengths, so light sources will always be damaging to some extent.

However, since Promolux lamps minimize the emission of damaging visible spectrum and UV wavelengths, using Promolux lamps will reduce shrinkage by 30 to 50 percent compared to the shrinkage caused by standard dairy display case lights. These savings will vary depending upon the duration of light exposure, which can vary from day to day and from hour to hour; the type of packaging; the fat content; and how the dairy product has been processed.