Sensory Evaluation of Cucumbers Treated with Blue Light

Blue light delivered at wavelengths of 405 to 470 nm has been demonstrated to inhibit growth of bacteria on foodstuffs. This study investigated the effect of a narrow band of visible light on the color, texture, and flavor (organoleptic) properties of cucumbers. Previous research in this area has focused on either broad-spectrum light or specifically the UV bands of energy. Two experiments were performed, a sensory evaluation and a discriminative test. in both experiments, half of the cucumbers were irradiated with 464 nm at 18 J/cm2 and half were left untreated. For the sensory evaluation, each evaluator received a treated cucumber slice and an untreated cucumber slice, then rated each slice based on organoleptic properties using a 9-item scoring sheet. For the two-out-of-five test, each evaluator received five slices, two slices of treated cucumber and three slices of untreated cucumber. The evaluators were asked to group the cucumber slices based on how the slices were prepared. Statistical analysis revealed that trained sensory evaluators were unable to distinguish between treated and untreated samples using sensory assessment. Blue light does not diminish the organoleptic qualities of the tested vegetables and appears to be at least as acceptable, from an organoleptic perspective, as other light decontamination methods.