Effects of Blackcurrant and Apple Mash Blending on the Phenolics Contents, Antioxidant Capacity, and Colour of Juices
Jan Oszmiański , Aneta Wojdyło
AbstractThe objective of this research was to evaluate the effect of blackcurrant mash blended with apple pulp during juice production and storage on its phenolic composition, antioxidant activity, L-ascorbic acid, and colour. Five variants of samples were prepared: apple juices from two cultivars: the Shampion and Idared cultivars without and with 20% of blackcurrant pulp and blackcurrant juice which were stored at 4 degrees C and 30 degrees C for 6 months. The apple juices prepared from the Idared and Shampion cultivars had a very low L-ascorbic acid contents (1.32 mg/l and 6.26 mg/l, respectively) whereas blackcurrant juice showed the highest amount Of L-ascorbic acid, i.e. 704.3 mg/l. The addition of 20% of blackcurrant pulp before apple crashing resulted in a great difference between L-ascorbic acid contents in juices. The addition of blackcurrant fruits before apple crushing had a statistically significantly different (P < 0.05) influence on phenolic compounds, especially in Idared blended pulp. As compared with the control samples, flavan-3-ol concentration increased 4 times in juices made from 80% of Idared apples blended with 20% of blackcurrant fruits. Apple pulp blended with blackcurrant was richer in hydroxycinnamic acids (especially caffeic, p-coumaric, and neochlorogenic acids) than juices made only from apples. The results ranged from 83.05 to 3297.6 mu M T/100 ml for DPPH (1,1-diphenyl-2-picrylhydrazyl radical), from 20.64 to 490.93 mu M T/100 ml for ABTS (2,2'azinobis-(3-ethylbenzthiazoline-6-sulphonic acid)), and from 1.52 to 37.35 mu M T/ml for FRAP (Ferric reducing antioxidant power assay) for apple juice made from the Idared cultivar and for blackcurrant juice, respectively. The highest level of the antioxidant capacity (P < 0.05) observed in the blackcurrant sample was due to the effect of the high anthocyanin and ascorbic acid contents. The apple juice colour showed a moderate degradation with time as indicated by the slight reduction of L* values in the samples stored at 4 degrees C for 6 months, and a much higher decrease of L* values in the samples stored at 30 degrees C. The lightness of the apple blended with blackcurrant increased during storage as a result of the coloured anthocyanin degradation. The temperature during the sample storage (30 degrees C) had a significant influence, resulting in a higher degradation of all phenolics compounds analysed, colour and antioxidant activity.
|Journal series||Czech Journal of Food Sciences, ISSN 1212-1800, (A 15 pkt)|
|Publication size in sheets||0.65|
|Keywords in English||blackcurrant; apple; juice; phenolic compounds; L-ascorbic acid; antioxidant activity; colour; storage|
|Publication indicators||= 21; = 27; : 2009 = 0.625; : 2009 = 0.602 (2) - 2009=0.763 (5)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.