Kinetic evaluation of color, texture, polyphenols and antioxidant capacity of Irish York cabbage after blanching treatment

School of Food Science and Environmental Health, College of Sciences and Health, Dublin Institute of Technology, Cathal Brugha Street, Dublin 1, Ireland
Food Chemistry (Impact Factor: 3.33). 01/2011; DOI: 10.1016/j.foodchem.2011.08.032

ABSTRACT In the present work, York cabbage was blanched between 80 to100°C with an increment of 5°C for up to 14 min and kinetics of the different physio-chemical properties were studied. Significant reductions in the texture, color, polyphenols (PPs) and antioxidant (AO) capacity were observed due to blanching. Total phenolic and flavonoid content retained ranged from 19.6-24.5 and 22.0-25.7%, respectively. Heavy losses in the AO capacity also occurred as a result of blanching, which was evident with a loss of 74.0-82.0% in activity as compared to raw York cabbage. Textural studies showed that blanching caused a significant reduction in firmness in the range of 24.0-73.2% and similar trend also observed for color. Kinetic evaluation of degradation was carried out for all the studied quality parameters. The fractional conversion (FC) first-order reaction model showed a good fit for the different studied parameters with the coefficient of determination ranging from 0.892-0.992 except for texture and color, which followed first order and zero order kinetics, respectively. The temperature effect followed the Arrhenius law with activation energy for polyphenolic content, AO capacity, color and texture calculated as 9.22-11.5, 9.05-35.05, 15.73 and 33.8 kJ/mol K, respectively.

  • [Show abstract] [Hide abstract]
    ABSTRACT: This work aimed at assessing the effect of heat treatment and frozen storage on the sensory and chemical properties of chicory with the goal of optimizing the heat pretreatment-storage condition to best preserve the chemical and sensory properties of chicory. Raw, boiled (10 min), blanched (90 °C for 60 s) and steamed (for 20 s) chicory samples were produced and stored at −6 °C, −12 °C or −18 °C for 4 months. Chemical analyses (moisture, ash, vitamin C, peroxidase activity, chlorophyll and color) and sensory evaluation (QDA and hedonic evaluation) were conducted. Treatment significantly influenced all chemical variables (p < 0.001), except for moisture; and so did freezing temperatures for a-value (p < 0.001), chlorophyll-a, peroxidase activity, vitamin C and ash (p < 0.01), total chlorophyll, moisture and b-value (p < 0.05). Differences were obtained for age for all chemical variables (p < 0.001). Treatments affected consumers' acceptability of chicory and QDA showed that boiled chicory was significantly more tender, less chewy and crunchy and needed less time to disintegrate than other samples. PCA showed that PC1 and PC2 separated attributes based on type and intensity of treatments, respectively. It is recommended to use blanching at 90 °C for 60 s and freezing at −12 °C or −18 °C to best preserve the quality of chicory.
    Lebensmittel-Wissenschaft und-Technologie 09/2014; 58(1):230–238. · 2.55 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The present study was conducted in order to evaluate the effects of blanching on the total and individual phenolic and antioxidant activities of 4 young sprouts of medicinal plants: dureup (Aralia elata), caster aralia (Kalopanax pictus), tree-of-heaven (Cedrela sinensis), and ogapi (Acanthopanax sessiloflorus). Caster aralia and dureup displayed significant reduction of Fe2+ chelation following blanching, but no alteration of DPPH or ABTS radical scavenging activity. Blanched ogapi displayed lower Fe2+ chelation as well as decreased DPPH and ABTS radical scavenging activities compared to raw sample. In contrast, tree-of-heaven displayed significantly increased antioxidant activity after blanching. Major phenolic compounds in mountain vegetables were chlorogenic acid and vanillic acid. In particular, chlorogenic acid contents increased by 11.2–68.1% in all vegetables except for ogapi after blanching. The results of this study show that blanching might be a useful tool for improving the beneficial properties of tree-of-heaven.
    Food science and biotechnology 06/2013; 22(3). · 0.70 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Rheological behavior and green color retention are important parameters during thermal processing of pureed leafy vegetables. In this study, an attempt was made to investigate thermal effect on the color and rheological characteristics of rocket (Eruca sativa L.) purees made from leaves with and without stems. The color degradation kinetics of rocket puree was studied at temperatures between 60 and 110 �C using fractional conversion technique. The degradation kinetics of puree followed a 1st order reaction kinetics and the activation energy values for puree with and without stems were ranged between 38.90 and 51.21 kJ/mol. Effects of blanching on oscillatory and steady flow rheology of puree made from leaves with and without stems were studied in the temperature range of 25 to 70 �C. All puree samples exhibited an elastic modulus that is larger than the loss modulus in the tested frequency range. Blanched leaf puree exhibited the highest mechanical strength at 70 �C. The steady flow data fitted the Herschel– Bulkley model well. The complex viscosity and the apparent viscosity at similar frequency and shear rate range failed to follow the Cox–Merz rule. Scanning electron microscopy and sieve-analysis revealed that the leaf puree had smaller particle sizes than puree with stems.
    Journal of Food Engineering 01/2013; 119(3):660-667. · 2.28 Impact Factor

Full-text (3 Sources)

Available from
May 26, 2014