Withering as first stage in black tea manufacturing is very important for producing black tea with high quality. During the tea green leaf withering, reduction in moisture content of the tea leaves is accompanied by occurrence of biochemical interactions that play an important role in black tea quality. Withering stage includes two parts as physical and biochemical withering. Withering time duration play an important role in biochemical interactions. In the present study, impact of withering time on the quality of black tea was examined based on environmental conditions and green tea quality through colorimetriy experiments and sensory quality evaluation by tea tasters. Also tea water extract was determined. A laboratory scale trough was used for withering operation. Temperature of blown air was 27°C and air flow rate was adjusted in 6.3 m3/min per 1 kg tea green leaf. Withering time was considered with five levels in three replications. Results related to determination of tea water e

Withering, Trough, Tea Processing, Duration, Green leaf, Sensory quality.

According to the results withered leaves in 16 hours had good biochemical properties and high sensory quality score and withering in 8 hours resulted in black tea with poor biochemical and sensory quality. Also impact of withering time on liquor tea brightness when air flow rate was adjusted in 0.63 m^3/min per 1 kg green tea leaves, was none significant. All of the sensory quality attributes play an important role in tea final quality, because all of these attributes had a significant linear correlation with total quality of black tea. Withering time duration is very crucial for biochemical attributes and controlling and monitoring this stage can help to produce black tea with high quality

Farshad Soheili-Fard, Hamid Reza Ghassemzadeh and Seyed Babak Salvatian (2015). Impact of Withering time duration on some Biochemical Properties and Sensory Quality Attributes of Black Tea .Biological Forum – An International Journal 7(1): 1045-1049.