Effect of CTC processing on quality characteristics of green tea infusion: A comparative study with conventional orthodox processing

Abstract

Traditionally, green tea is manufactured using orthodox processing methods. The CTC (curl, tear, and crush) method, widely employed in black tea processing, has minimal application in green tea production. However, it exhibits potential in terms of extraction efficiency to infusion. This study investigates the CTC method for producing green tea (CGT) and compares the extraction efficiency of bioactives to infusion with orthodox green tea (OGT). Total polyphenol, catechins, caffeine, and theanine extraction efficiencies were evaluated in both CGT infusion (CGTI) and OGT infusion (OGTI), along with water extract, antioxidant activity, color parameters, and sensory attributes. Results showed the amount of the bioactive compounds extracted from 2.00 g OGT could be attained from 0.75 to 1.00 g of CGT. This indicates that CGT is 100 to 167% more efficient in terms of the contents of bioactives in the infusion than OGT. This finding corroborates the observations of higher antioxidant activity of CGT compared to OGT. CGTI achieved similar taste and color perceptions with half the amount of OGT or even less. This enhanced extraction efficiency, along with CGTI's taste and color characteristics, can facilitate its commercial production, benefiting consumers and the tea industry. Industrial relevanceThis study provides comprehensive information on CTC green tea to the tea industry, which is the first of its kind with such in-depth details. As evident, the CTC processing mode of green tea promises more affordability to its growing consumers leading to increased demand for this type of tea which will immensely benefit the tea industry.