For quantitative determination of L-malate (L-malic acid) and drug effects on malate metabolism. Key Features: Fast and sensitive. Use of 20 µ L sample. Linear detection range 0.02 to 2 mM L-malate in 96-well plate assay. Convenient. The procedure involves adding a single working reagent, and reading the optical density at time 15 minutes. Room temperature assay. No 37° C heater is needed. High-throughput. Can be readily automated as a high-throughput 96-well plate assay for thousands of samples per day. Method: OD565nm. Samples: Malate in food, juice, beverage and other agricultural products. Species: All. Procedure: Assay takes 15 min. Kit size: 100 tests. Detection limit: 0.02 mM.