Photoacoustic spectroscopy as an approach to assess chemical modifications in edible oils

Journal of the Brazilian Chemical Society

Silva, Charles L. da¹  Universidade Federal de Viçosa, Viçosa, Brazil¹  Reis, Alexandre M.¹  Instituto Federal do Sul de Minas Gerais, Pouso Alegre, Brazil¹  Martins, João Paulo¹  Campos, Júlio César C.¹  Santiago, Bruno C. L.¹  Albuquerque, José Eduardo de¹  Coimbra, Jane S. R.¹ 

关键词: thermal degradation;    fatty acid;    food process;    physicochemical properties;    vegetable oil;   

DOI  :  10.5935/0103-5053.20130047

学科分类：化学（综合）

来源: SciELO

【 摘 要 】

Photoacoustic spectroscopy was used to obtain optical properties of edible soybean, canola and olive oils as well to evaluate the oil modifications induced by thermal treatment. The normalized photoacoustic signal intensity and its phase were independently measured as a function of wavelength of the radiation source. The oil samples were heated up to the smoke point and then for additional 30 min in order to degrade them. After, the oil samples were cooled down and photoacoustic measurements were conducted in order to obtain the absorption spectra of samples at both degraded and non-degraded conditions. Comparisons between the two conditions indicate that the degraded oil samples exhibited widening of the absorption bands in ultraviolet region of the spectra, relative to the respective non-degraded sample. Also, the peaks of those absorption bands presented a red shift.

【 授权许可】

Unknown