Effect of l-ascorbic acid addition on quality, polyphenolic compounds and antioxidant capacity of cloudy apple juices

Abstract

Polyphenols are one of the most important dietary antioxidants, and the apples, being a major source of polyphenolic compounds. There is increasing evidence that the consumption of fruit and their preserves, which are rich sources of vitamins and phenolics, is negatively associated with lung cancer and coronary heart disease. The influence of ascorbic acid addition on the quality, polyphenolic profile and antioxidant capacity in 14 selected varieties of apple juices during the 3 years of study was examined. Evaluation of changes of ascorbic acid content allowed to demonstrate the differences in susceptibility of apples on the enzymatic oxidation. The study shows that the variations of the least susceptible to oxidation of ascorbic acid are 'Shampion' and 'Topaz', and to a lesser extent, 'Szara Reneta', 'Arlet' and 'Jonafree' apples. A total of 17 kinds of polyphenolic compounds including catechins, procyanidins, hydroxycinnamates, flavonols, anthocyanins and dihydrochalcones were identified in apple tissues by HPLC with DAD analysis and after phloroglucinolysis and LC-MS. During the 3 years of study, the addition of ascorbic acid positively affects on the polyphenol compounds and antioxidant capacity (DPPH, ABTS and FRAP), increasing their content in the analyzed samples by 65 and 433, 328 and 300 %, respectively. The correlation coefficient between DPPH, ABTS and FRAP antioxidant capacity and ascorbic acid was 0.71, 0.71 and 0.72, respectively.

Polyphenols, ascorbic acid and antioxidant capacity of commercial nutritional drinks, fruit juices, smoothies and teas

“…). The addition of AA has been shown to increase AOC in apple and other fruit juices by protecting phenolic acids from oxidation (Miller & Rice‐Evans, ; Kolniak‐Ostek et al ., ). However, the amounts of AA measured in the beverages used in this study seemed to have limited contribution to the AOC (Figs and ).…”

Green tea extract as an anti‐browning agent for cloudy apple juice

“…Likewise cysteine, at high concentrations, produced undesirable odour and caused a bleaching effect . AA is the most frequently used for enzymatic browning prevention during processing and storage of apple juice . It reduces o ‐quinones to diphenols but it may be oxidised completely and browning may occur due to the formation of melanins .…”

Raw Juice Concentration by Osmotic Membrane Distillation Process with Hydrophobic Polymeric Membranes

“…Moreover, OMD is evaluated in terms of the concentration of aqueous solutions of thermally labile pharmaceutical products (Kolniak-Ostek et al 2013;ElAbbassi et al 2013).…”