Availability of gac fruit is seasonal. The gac fruit is only available three months out of the year. In Vietnam, gac vines are grown mainly in the red river delta areas. Harvesting of the fruits start on September and lasts until December. Gac fruits are picked when they are at optimal size, weight, and color. Poor post-harvest handling and transportation reduce the shelf-life of the fruit. After harvesting, without proper storage, fruits perish quickly and lose market ability after one week. In the markets of urban areas, gac fruits are available for only about 3 months, from November to January. Gac fruit, Momordica cochinchinensis Spreng contains extraordinarily high levels of carotenoids, especially β-carotene and lycopene, and a comparatively high content of α-tocopherol (vitamin E) and of polyunsaturated fatty acids. The aim of this study is therefore to develop an understanding of suitable conditions for the processing of Gac fruit, with three pretreatment methods: blanching, blanching in citric acid solution and steaming. The result shows that steaming in 6 minutes is the best pretreatment method for the protection and maintenance of total carotenoid content in gac powder.
Keywords: Blanching, Carotenoid, Gac Fruit, Steaming
