ARS | Publication request: Effect of edible coatings and other surface treatments on pericarp color of Thai lychee cultivars

Submitted to: Florida State Horticultural Society Meeting
Publication Type: Abstract Only
Publication Acceptance Date: March 15, 2007
Publication Date: May 10, 2007
Citation: Rattanapanone, N., Plotto, A., Baldwin, E. 2007. Effect of edible coatings and other surface treatments on pericarp color of Thai lychee cultivars. Florida State Horticultural Society Meeting. Abstract No. HP2.

Technical Abstract: Lychee fruit have a brilliant red pericarp upon harvest that turns brown during shipping and storage. 'Hong Huay' and 'Jugkapat' lychee fruit (Litchi chinensis Sonn.) were harvested at the commercial stage (90-100% red pericarp) in Thailand. In four separate experiments, fruit with pedicels were dipped for 30 s in various treatment solutions including: no dip and water as controls, ascorbic acid (AA), citric acid, acetic acid, chitosan, HCl, and two Semperfresh products, in an effort to retard browning of the percarp. Fruit were air-dried, and stored at 2 or 10 C with 90% relative humidity for 1-3 weeks. Total soluble solids (TSS), tritratable acidity (TA), weight loss, total ascorbic acid (TAA) and color (hue angle and chroma) were measured every day or once a week. During storage, TSS and pH generally increased while TA and TAA generally decreased (except for those treatments that included AA). Most treatments reduced weight loss compared to untreated fruit. Treatment of lychee fruit with acidified coatings including Semperfresh, acidified Semperfresh (with 2% citric acid), Semperfresh Lychee Treatment Power (LTP) + citric acid and chitosan + HCl sometimes resulted in brighter, redder color than control fruit, as evidenced by lower hue angle or higher chroma values.