Changes in Carotenoid Composition during Preparation and Storage of Frozen and Freeze-dried Squash

Abstract

Changes in carotenoid composition during blanching and storage of frozen and freezedried winter squash were determined. (1) There was no loss of carotenoid due to the blanching process. (2) Lutein decreased at the same rate as total carotenoid content, but β-carotene was stable during the process of freezing. (3) Under frozen storage, β-carotene decreased at the same rate as the total carotenoid content, but the amount of lutein was stable. After 3 months under frozen storage, a 32% loss in the amount of β-carotene was observed. (4) There was no loss of carotenoids during the process of freeze-drying. (5) During storage of freeze-dried squash at 30°C, loss of β-carotene reached 15, 20 and 53% after 1 month, 2 months and 3 months, respectively. However, after 3 months storage at 0°C, the loss of β-carotene was only 10%. (6) The total carotenoid content was 15.5mg/100g in the raw squash pulp and it was composed of 48% lutein, 18% antheraxanthin, 14% violaxanthin, 11% β-carotene, 3% zeaxanthin, 2% β-cryptoxanthin, trollein and neoxanthin.