Effect of postharvest L-arginine or cholesterol treatment on the quality of green asparagus (Asparagus officinalis L.) spears during low temperature storage

Bundled green asparagus (Asparagus officinalis L.) were vertically placed in L-arginine (0.05 mmol L-1) or cholesterol solution (0.52 mmol L-1) and stored at 4 +/- 0.5 degrees C for 30 days. The changes of general appearance, disease incidence, weight loss, water-insoluble solids, lignin, total phenolics, chlorophyll content, malondialdehyde (MDA), phenylalanine ammonia lyase(PAL) enzyme activity, antioxidant capacity and soluble protein content were investigated during storage. General appearances of asparagus treated with L-arginine or cholesterol for 18 days were rated as good and excellent, unlike that of untreated spears. L-arginine or cholesterol treatment significantly reduced disease incidence and losses of fresh weight and chlorophyll content. Total phenolics and soluble protein contents were maintained higher in L-arginine-treated or cholesterol-treated asparagus, whereas water-insoluble solids and lignin content was significantly reduced. L-arginine treatment or choldsterol treatment also decreased the accumulation of malondialdehyde (MDA) and increased the antioxidant capacity. These results indicated that L-arginine or cholesterol treatment could be selected to maintain postharvest quality of green asparagus and provide long storage life.