Studies on the physical and chemical changes associated with development of broccoli curds to determine the maturity stage and the suitable age for harvesting

Hamad S. A. S; S. A. Shanan; A. A. Mohammed and A. E. Ashmawi

Abstract

Two experiments were carried out on broccoli cultivar "Marathon" in the winter seasons of 2013-2014 and 2014-2015 at the farm of the Faculty of Agriculture, AL-Azhar University, Nasr City, Cairo. Curds of 5, 10, 15, 20, 25 and 30 days from the start of bud formation were used to study the changes occurred in the physical and chemical characteristics during developmental stages which stored under cold storage (8ºC and 60-65% RH) to determine the maturity stage and the most suitable age for harvesting. The obtained results showed that there was a slow increase in the initial periods in the curd fresh weight and size until the age of 20 days which was followed by a sharp increase up to the age of 30 days exhibiting statistically a curvilinear shape. Meanwhile, the curd diameter increased from the start of curd formation up to the last examining age establishing a linear shape. Moreover, rapid accumulation in the contents of total chlorophyll, total carotene, titratable acidiy, ascorbic acid and total sugars were detected up to the age of 25 days then followed by a decline up to the last age showing statistically a curvilinear shape. In addition, a linear curve with T.S.S. and dry weight which increased steadily with the progress of age from the start of curd formation up to the last examined age of 30 days. Furthermore, storing the curd developmental stages at 8ºC and 60-65% RH exhibited that the age of 25 days reflected the minimum loss in weight, unmarketable percentage, lower degradation in colour during storage and contained and the highest contents of total chlorophyll, T.S.S, ascorbic acid and total sugars. So, the curd maturity stage was determined at the age of 25 days from bud formation which consider fortunately the most suitable age for harvesting.

Key words

-broccoli, curds, maturity, harvesting