Effective collection of protein-enriched cells from green tea residue: An innovative process for leaf protein production

Green tea residue (GTR) contains a high protein content. However, the protein in GTR can't be effectively extracted using traditional methods. Thus, a novel method using ethylenediamine tetraacetic acid (EDTA), ammonium oxalate, or Celluclast® 1.5 L were used to disperse leaf tissues and to collect mesophyll cells to enrich the protein. Compared with EDTA or ammonium oxalate treatment, Celluclast® 1.5 L treatment achieved the highest amounts of mesophyll cells, about 2.7 × 10⁶ g⁻¹ of GTR. The number of collected mesophyll cells was positively and linearly correlated with the extraction rate of glucose and xylose, indicating that cellulose and hemicellulose were key components influencing cell collection. Celluclast® 1.5 L treatment enriched the protein content by 1.65 times in collected mesophyll cells to 50% protein content with a protein recovery of 88%, providing a novel scheme to obtain high-quality leaf protein for the food industry.