Please check the following links

Determination of Antioxidant Properties of Fruit Juice by Pa..http://www.revistadechimie.ro/pdf/glewitzky.pdf

Conference Paper Total antioxidant activity and total phenolic compounds of o...

http://dergipark.gov.tr/download/article-file/411779

Thank You Sir

I have doubt too.

Is Phosphomolbdenum assay applicable for pineapple fruit antioxidant assay

You could test the antioxidant capacity of a volume of pineapple juice when challenged with reactive oxygen species such as superoxide or hydroxyl radical. There is a simple to use ABEL antioxidant test with superoxide which uses ascorbate as a standard. See www.knightscientific.com (kits). This test requires a luminometer, either a microplate luminometer or a tube luminometer. You can also produce ABEL-RAC (relative antioxidant acticity) of the juice, also using the superoxide antioxidant test, but this time you will obtain a score per mg/ul which you can use to compare to any other juice or to other pineapple juices. It is a good way also to measure real time shelf life.

I forgot to add a kit insert for the ABEL superoxide test kits. I also have a more uptodate background document on ABEL-RAC as well as a publication.

Please contact me if you would like to discuss this further. Jan