Effect of Different Blanching Methods on the Activity of the ‎Peroxidase Enzyme and the Quality Characteristics of Frozen ‎Carrot Slices

Batool Alansari*(1) and Abdulrahman Hasan Laftah(1)

(1). Department of Food Science, Faculty of Agriculture, University of Basrah, Basra, Iraq.

(*Corresponding author: Dr. Batool Alansari. E-Mail: batool.Mahmod6@gmil.com).

Received: 04/04/2020                               Accepted: 03/06/2020


This study was carried out between January to February 2019 in Basra University, Faculty of Agriculture, at laboratory of Food Science Department  to determine the effect of different blanching methods (boiling water immersion T1, steam T2 and microwave T3) for 5 minutes on the activity of the peroxidase enzyme and the quality characteristics of the carrot slices stored in freezing for a period of 30 days. The activity of the peroxidase enzyme was measured for all treatments and some chemical and sensory tests of carrot slices were performed before and after freezing. The results showed that there were significant differences at the probability level (P <0.05) between T3, T2, and T1 treatments compared to the T0 control treatment (un blanched carrots), as the enzyme activity decreased gradually as the storage period progressed. It is noted from the results that banching time was insufficient to stop the activity of the enzyme, which is evidence of the efficiency of the blanching process, while the percentage of moisture and pH increased, while the ratio of dry matter, the percentage of total acidity and the content of ascorbic acid to the treatments T3, T2, T1 decreased compared with T0 (control treatment). The results of the sensory tests showed that there were no significant differences at the probability level (P <0.05) between the T3, T2, and T1 treatments compared to the T0 (control treatment). The best treatment was the blanching method with boiling water immersion and microwave blanching in terms of color and texture, whereas there were no differences in taste and smell for all treatments after the end of the freezing storage period.

Key words: Peroxidase, Freeze storage, Carrot, Blanching, Ascorbic acid.

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Effect of Planting Date and Plant Density on Growth and Yield of (Daucus carota L.) plants in Hama Governorate

Ahmed Mohamed Jarjanazi*(1)

(1). Second Faculty of Agriculture, Aleppo University, Aleppo, Syria.

(*Corresponding author: Dr. Ahmed Mohamed Jarjanazi. E-Mail: Jarjnazi1965@gmail.com.

Received: 24/11/2018                                Accepted: 16/01/2019


The experiment was conducted to study the effect of sowing the carrot (Daucus carota. Var. Nantes) on three dates (24/9, 8/10 and 23/10) and two densities: high (80) plants/m2 and low (40) plants/m2 under the conditions of Hama governorate, according to the split design. The early sowing showed a significant superiority over the other dates in all the studied traits (germination; maturity; length of leaves; length, diameter and weight of root; number of leaves per plant; fresh plant weight, and marketable productivity). The low density was significantly higher in the number of leaves per plant; length, diameter and weight of root, and fresh plant weight, while the opposite was noticed in terms of the length of the leaves and the marketable productivity. While the speed of germination and maturity were not affected with the plant density. In terms of the interaction between the date and the density, the plants that were sown on the first date at low density achieved the highest germination velocity; maturity; length, diameter and weight of root; number of leaves per plant and fresh plant weight (10 days, 118 days, 23.1 cm, 31.33 mm, 136 g, 15 leaves/plant, 158 g/plant, respectively), while the highest leaf length and marketable productivity (28 cm, 5.71 kg/m2 respectively) were achieved at the first date and high density.

Keyword: Carrot, Daucus carota, Sowing date, Density; Marketable productivity.

Full Paper in Arabic: PDF