摘要

Free soy oil and soy oil treated with polyphenols extracted from sea buckthorn fruits, BHA and BHT synthetic antioxidants was submitted to thermal oxidation for 8 days at 62 C and to photo-oxidation for 30 min. at 254 nm wave-length light. Oxidation processes were evaluated by determining the peroxide value, para-anisidine value and the absorbance in UV domain. Using second derivative spectroscopy, it was determined the cis,trans/trans,trans conjugated dienes ratio. The concentration of 100 ppm sea buckthorn polyphenols determined the decrease of peroxide values and para-anisidine values after a pattern similar to BHT synthetic antioxidant and also the increase of cis,trans/trans,trans conjugated dienes ratio in case of soy oil submitted to thermal oxidation. The increase of cis,trans/trans,trans conjugated dienes ratio was also recorded in case of soy oil submitted to UV light oxidation, under the influence of sea buckthorn extract. The obtained results indicate that polyphenols extracted from sea buckthorn are able to protect soy oil against thermal and photochemical oxidation.

  • 出版日期2010-6