The Pink, Brown and Yellow Discoloration of Coconut Water and Products

When I was employed in a juice processing industry, one of our biggest problem was the discoloration of coconut water. Young coconut water concentrates, immediately  after processing were fine but were experiencing top discoloration after some time in cold storage. The top were becoming reddish brown. We suspected it was a reaction involving oxygen but wasn’t able to find any suitable solution. The company opted dropping the product line.

Lately, the raw nata de coco I left under the refrigerator got frozen and became pink. I thought it was still related to our previous experience. I guess it is time to find its real cause and solution if possible.

nata de coco with pink liquid

I found only two literature but I think they are enough.

Optimum activities of polyphenoloxydase (PPO) and peroxydase in green coconut water occurred at pH 6.0 and pH 5.5 at temperatures of 25°C and 35°C, respectively. However, various levels of PPO and POD activity are reported in literature. These enzymes are assumed to be responsible for the discoloration (pink, yellow or brown) frequently observed in coconut water. Porexydase activity was also observed in coconut water samples stored at -20°C.

Coconut water uses, composition and properties: a review. By:  Alexia Prades, Manuel thDornier, Nafissatou Diop, Jean-Pierre Pain.

The pink discoloration in coconut water is a result of the initial enzymatic reaction of the polyphenol oxdydate (PPO) on the phenolic substrates which are naturally present in the product. Enzyme activity is further enhanced by metal contamination such as copper and exposure to high temperature during processing and storage. Younger coconuts are more prone to discoloration than matures.

Control of pink discoloration in coconut water. By:  B. Garcia, D.B. Masa, M.J. Rodriguez and R. Rolle

The last set of authors belong to Philippine Coconut Authority. I suggest contacting the agency if you want to know more about control of coconut water discoloration.

Marvin is the lead chocolate maker of Ben and Lyn Chocolate Inc. Has strong background in food research and development. Occasionally conducts training and lectures. Accepts coaching and consultancy services. Lecturer of Cocoa Foundation of the Philippines.

Nata de Coco – Drying and Reconstitution?

The drying and reconstitution experiment on kaong meat went well. I successfully dried few kaong meats to a hard rock like thing. All came back to normal after soaking in tap water overnight.

The trick might also work on nata de coco cubes. I secured few pieces and dried them for one and one half day. Pieces became flat like a transparent sheet of paper. Then I soaked them in heavy syrup in hope that it can reabsorb water together with sugar particles. A sweet nata de coco after…

nata de coco cubes dried nata de coco flattened nata de coco in syrupto be continued….

Update as of April 26, 2013: The nata de coco can be dried successfully but bringing it back to its original form is not possible.  No increase in size observed after 24 hours of soaking in heavy syrup. I drained the syrup and replaced it with plain water. No increase in size either after another 24 hours.

Marvin is the lead chocolate maker of Ben and Lyn Chocolate Inc. Has strong background in food research and development. Occasionally conducts training and lectures. Accepts coaching and consultancy services. Lecturer of Cocoa Foundation of the Philippines.

The Possibility of Real Sweet Kaong and Nata de Coco

Kaong meat and nata de coco have things in common. First, they are both semi-transparent white. Second, they are both chewable, not so soft and not so tough, just enough for enjoyable munching. Third, hard to sweeten or it is more right to say that both cannot be sweetened.

Do you notice it too? Both if boiled in syrup for long and short period never take in the syrup sweetness. It never take any no matter how light or how strong the syrup is.  Sweetened nata de coco and sweetened kaong meat are sweet just because they are submerged in syrup. It is the syrup that is tricking us to believe that they are sweet.

Please tell me I a wrong!

What is preventing the sugar particles from entering the white semi transparent product?  Maybe the fiber matrix is well built that it never allow entry and exit of water and solutes.

Recently the drying and reconstitution experiment, the pieces of dried kaong meat regained their original form after soaking in water for 24 hour. The toughened fiber matrix reabsorbed water. How I wish I soaked them in syrup instead of plain water so I could see whether I can make a real sweet kaong meat. I want to know if it can absorb sugar particles and water together.

Gonna test this idea for both kaong meat and  nata de coco.

yet another set of kaong meatsUpdate as of April 26, 2013: My concept was proven wrong on nata de coco. It can be dried successfully but could not be returned back to its original form. See, Nata de Coco Drying and Reconstitution?

Marvin is the lead chocolate maker of Ben and Lyn Chocolate Inc. Has strong background in food research and development. Occasionally conducts training and lectures. Accepts coaching and consultancy services. Lecturer of Cocoa Foundation of the Philippines.