Should we avoid the milk and green tea combo? “Milk protein negates Catechins’ benefits because Catechins bind with milk protein.” This used to be true, and we still find this statement online. But now recent studies have discovered that is not quite correct.   

The interactions between catechins and proteins alter the protein structure, leading to a partial decrease in antioxidant activity of EGCG, the protein protects EGCG against degradation.”    

While the above statement is still true; recent studies have revealed more about the positive outcome from the “binding” activities, and science says now milk protein helps to enhance the bioavailability of Catechin benefits:

“Milk proteins, containing caseins and whey proteins, were considered as ideal carriers for delivering catechins. Sodium caseinate adsorbed at the oil water interface, can load high ratios of EGCG. Casein micelles can be used as protective carriers for EGCG in foods. It was demonstrated that nanoencapsulation of EGCG in casein micelles did not diminish antiproliferative activity of the catechins on colon cancer cells, compared with free form EGCG. Accordingly, casein micelle is considered to be an ideal platform for catechin delivery while the binding of caseins with EGCG would not affect the bioaccessibility of EGCG.”  

The above quotation was taken from this scientific report:  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6225109/  (September 2018).      

The following study was done in Japan to see if green tea and milk together is a taboo or not. They observed the benefits of EGCG lasted longer when EGCG was taken with milk protein than when EGCG was taken by itself.
https://www.j-milk.jp/report/marketing/f13cn00000000w8r-att/8d863s000006uqvm.pdf 

  They looked at the influence of milk protein over the EGCG as below:

milk protein and green tea

Fig. 17 shows Green Tea Catechins decreases blood pressure and its peak is 2 hours after the intake. Milk protein also decreased blood pressure and its peak was 2-4 hours. When they were taken together, the level of effect was about the same as Catechin itself, but it prolonged for 8 hours.  

Fig. 18 shows The same prolonged effect was observed when Green Tea Catechins and Powdered fat free milk were taken together.   

This study also mentions whey showed a better effect than casein in terms of the extending effect. 80% of milk protein in casein and 20% is whey. When you buy yogurt, often you see the watery liquid at the top–that is the whey. 

Matcha Latte and smoothies have now a GREEN light backed by science!

References:

  • Sabouri S., Geng J., Corredig M. Tea polyphenols association to caseinate-stabilized oil–water interfaces. Food Hydrocoll. 2015;51:95–100. doi: 10.1016/j.foodhyd.2015.04.034. 
  • Sabouri S., Wright A.J., Corredig M. In vitro, digestion of sodium caseinate emulsions loaded with epigallocatechin gallate. Food Hydrocoll. 2017;69:350–358. doi: 10.1016/j.foodhyd.2017.02.008.
  • Haratifar S., Meckling K.A., Corredig M. Antiproliferative activity of tea catechins associated with casein micelles, using HT29 colon cancer cells. J. Dairy Sci. 2014;97:672–678. doi: 10.3168/jds.2013-7263. 
  • Hu S., Wang T., Fernandez M.L., Luo Y. Development of tannic acid cross-linked hollow zein nanoparticles as potential oral delivery vehicles for curcumin. Food Hydrocoll. 2016;61:821–831. doi: 10.1016/j.foodhyd.2016.07.006.