Presentation is loading. Please wait.

Presentation is loading. Please wait.

Abstract The growing demand for organic food in the world requires the assessment of the value aspects of food quality, it’s safety, nutritional content.

Similar presentations


Presentation on theme: "Abstract The growing demand for organic food in the world requires the assessment of the value aspects of food quality, it’s safety, nutritional content."— Presentation transcript:

1 Abstract The growing demand for organic food in the world requires the assessment of the value aspects of food quality, it’s safety, nutritional content and biological-physiological process. Phenolic compounds are found in most fruits and vegetables. (Zhang and Hamauzu, 2005). Carrots and their fresh produce (shredded carrots, sliced carrots and carrot juice) may protect humans against certain types of cancer and cardiovascular diseases (Krinsky & Johmson, 2005). Correlations between antioxidant activity and phenolic compounds were determined by using three drying methods (carrots were sliced and dried in desicator +40 ºC and lyophilised under vacuum condition (freeze-dried) by –72 ºC) for sample preparation. Antioxidant activity was determined by using DPPH radicals spectrophotometrically. Introduction Carrots contain mainly hydroxycinnamic acids and derivatives. Among them, chlorogenic acid is a major hydroxycinnamic acid, representing from 42.2% to 61.8% of total phenolic compounds (Wang et al.,2006). In addition to the above compounds found in natural foods, vitamins C and E, beta-carotene and tocopherol are known to possess antioxidant potential. Research aim is to determine the total antioxidant activity and phenolic compounds, which are working as a free radical scavengers, peroxide decomposers, enzyme inhibitors, and synergists. Materials. Fresh carrots (Daucus carota L. Neptun) were provided by the Lithuania Horticulture institute (Babtai, Lithuania). Methanol (CH3OH) was of analytical grade (Sigma-Aldrich, Germany), 2,2- diphenyl-2-picrylhydrazyl hydrate (DPPH) was from Sigma-Aldrich (Germany). Bidistilled water was used for the experiments, (2N) Folin-Ciocalteu reagent was obtained from Sigma (USA), Na2CO3 p.a. (Chempur, Poland). Conclusions and perspectives : Antioxidant activity was determined using DPPH radicals. Influence of drying method (sliced and dried in desicator +40 ºC or lyophilised under vacuum condition (freeze-dried) by –72 ºC) was not significant p>0.05, but solvent concentration showed significant correlation with antioxidant activity and phenolic compound (p 0.05), significant for phenolic compounds (p<0.05). Acknowledgement Carrot samples provided by Institute of Horticulture in Babtai are acknowledged. Fig. 1. DPPH radical scavenger activity %. Significantly the best antioxidant activity shows 0.5g and 75% of sliced desiccated, freeze – dried and pressed desiccated samples in the Fig.1. The total phenolic content of carrots material varied from 0.07 to 0.31 mg/ml of the methanolic carrots extracts and from 1.51 to 7.01 mg/g of dry carrot content, expressed by gallic acid equivalent (GAE). Spectrophotometric analysis Methods: Spectrophotometric analysis: 1. Determination of total amount of phenolic compounds (expressed in galic acid equivalents mg/g for dry material according to the Folin- Ciocalteu colorimetric method ). 2. Determination of antioxidant activity (based on DPPH bleaching reaction slightly modified method of Brand-Williams et al.) Results Fig. 2. Content of phenolic compounds, using gallic acid as a standard and expressed as mg/g gallic acid equivalent (GAE) in dry carrots material (Folin-Ciocalteu method). Antioxidant activity % showed as a point of AOX.


Download ppt "Abstract The growing demand for organic food in the world requires the assessment of the value aspects of food quality, it’s safety, nutritional content."

Similar presentations


Ads by Google