14E-17 |
Effect of MAP storage on antioxidant activity, anthocyanins, phenolics and carotenoids of shredded orange and purple carrots |
C. ALASALVAR1, M. Al-Farsi2, P. C. Quantick2, R. Wicktorowicz3, and F. Shahidi4. (1) Dept. of Biological Sciecences, Univ. of Lincoln, Brayford Pool, Lincoln, LN6 7TS, United Kingdom, (2) Food Research Center, University of Lincoln, Lincoln, LN6 7TS, United Kingdom, (3) Air Products PLC, European Technology Group, Hants, RG24 8FE, United Kingdom, (4) Dept. of Biochemistry, Memorial Univ. of Newfoundland, 300 Prince Philip Dr., Saint John's, NF A1B 3X9, Canada Carrots are being consumed increasingly, mainly due to their perceived health benefits related to their polyphenols, carotenoids and antioxidant activity. Epidemiological surveys have shown that the consumption of polyphenols, including phenolics and anthocyanins, is inversely related to the incidence of coronary heart disease. The objective of this research was to compare the effect of storage under modified atmosphere packaging (MAP) on antioxidant activity, anthocyanins, phenolics and carotenoids of ready to eat shredded orange and purple carrots. Sensory changes were also assessed. Shredded orange and purple carrots were packed in both air (control) and MAP treatments (90%N2/5%CO2/5%O2 and 95%O2/5%CO2), and stored chilled for 13 days. Antioxidant activity was measured by oxygen radical absorbing capacity (ORAC), using a RF-450 spectrofluophotometer. Total anthocyanins were determined by a pH-differential method, using a spectrophotometer. Total phenolics were determined colorimetrically, using Folin-Ciocalteu reagent. Total carotenoids were measured colorimetrically, using a spectrophotometer. Sensory changes were assessed by 5 trained panelists. Statistical significance was checked by using a two-sample t test, assuming equal variances. Antioxidant activity and total carotenoid content did not change over the storage period in any of the treatments, whereas total phenolic content showed gradual increases in purple carrot. Athocyanin, which was only detected in purple carrot, showed decreases. Purple carrots contained 2.5 and 3 times more total carotenoid and antioxidant activity than orange carrots, respectively. The MAP treatment (90%N2/5%CO2/5%O2) gave better storage quality than other treatments for purple carrots. No significant (P >0.05) changes in any treatments were observed for orange carrots. The results also showed slight organoleptic differences between the control and MAP treatments for both carrots. Thus, purple carrots may be used in place of orange carrots to take advantage of their nutraceutical components. Moreover, high nitrogen treatment may be used in maintaining the storage quality of shredded purple carrots.
Session 14E, Nutraceuticals & Functional Foods: General I
|