Abstract:

Spiny amaranth (Amaranthus spinosus L.) is an important resource of wild vegetable in China. Its seeds have
been applied in crunchy rice candy which is a crisp, natural healthy food with a huge marketing potential greatly favored
by consumers. However, crunchy rice candy with added spiny amaranth seeds is susceptible to oxidative rancidity, flavor
deterioration and shortened shelf life. This experiment investigated the post-storage quality of the crunchy rice candy as well
as the fatty acid composition and physiochemical characteristics of spiny amaranth seed oil. In addition, changes in fatty
acid composition of spiny amaranth seeds before and after accelerated oxidation were monitored by gas chromatographmass
spectrometer (GC-MS). The analytical data showed that the average oil content of spiny amaranth seeds was 6.26%,
acid value 2.79 mg/g, saponification value 144.79 mg/g, iodine value 87.48 g/100 g, linoleic acid 33.91%, and the contents
of oleic acid, palmitic acid, stearic acid and squalene were 36.05%, 15.39%, 4.01% and 7.03%, respectively. After the
accelerated oxidation, squalene disappeared from spiny amaranth seed oil, and more fatty acids were formed as well as small
molecule substances such as aldehydes, esters, pyrazines, alkenes, anilines, phenols and ketones. Thus, squalene may be
the main cause of rancidity in crunchy rice candy with added spiny amaranth seeds. Aluminum foil vacuum packaging with
deoxidizer can effectively ease its rancidity.

Key words: spiny amaranth (Amaranthus spinosus L.) seed, crunchy rice candy, oil, rancidity