[5-1130-P] Postharvest/Food Technology and Process Engineering (5th)

[5-1130-P-02] Palm Oil based Wax Coating Maintained Postharvest Quality of Thai Lime cv. Paan Pichit#1

*Varit Srilaong¹, Nutthachai Pongprasert¹, Songsin Photchanachai¹, Panida Boonyaritthongchai¹, Kornkanok Aryusuk² (1. Division of Postharvest Technology, School of Bioresources and Technology, King Mongkut's University of Technology Thonburi(Thailand), 2. Division of Biochemical Technology, School of Bioresources and Technology, King Mongkut's University of Technology Thonburi(Thailand))

Keywords:Coating, Palm oil wax, Lime, Postharvest, Quality

Immature green lime fruit cv. Pann Pichit#1 is widely consumption in Thailand as an ingredient of Thai’s dish. Most of consumers prefer to have immature green lime due to its enriches with special aromatic compound, taste and flavor. Thus, to maintain the green color of lime fruit is very important for retarding quality losses. Peel yellowing is one of a major problem in lime fruit during postharvest period which lead to reduction of fruit qualities thus the inhibiting or delaying of chlorophyll breakdown is needed. There are several kind of postharvest technology to prolong storage life and maintain green color of fresh produces and one of them is coating technique by using natural based wax. According to Thailand produces a lot of palm oil and a byproduct from palm oil industry, palm oil wax, has potential to use as a wax based to form coating material. Thus, this research aimed to use palm oil based wax coating for maintaining quality of immature green lime cv. Pann Pichit#1. Lime fruit were harvested from commercial orchard and coated with palm oil based wax (PW) and commercial wax (CW), and then stored at 13^oC. Uncoated fruit was set as a control. Changes of lime fruit qualities including fresh weight loss, browning spot, chlorophyll content, ascorbic acid content and acetaldehyde content were investigated at 5 days interval. The results found that lime fruit coated with PW showed the lowest water loss compared with that of CW coated and the control, respectively. The percentage of peel browning spot occurrence was also reduced in the fruit coated with PW while the application of CW induced a browning spot to higher level than the control. This result was concomitant with the incidence of peel browning. Lime fruit coated with both PW and CW delayed the chlorophyll breakdown in the same trend while the continuously degradation of chlorophyll was observed in the control. There was no consistent change of ascorbic acid content in all treatments, anyway the content was slightly change from the initial until the end of storage. The accumulation of acetaldehyde in lime juice was initially observed on day 10 in all treatments and then declined throughout the end of storage with slightly difference among the treatments. From the results indicated that PW has potential to apply with immature green lime fruit during postharvest period. In addition, the use of byproduct from palm oil industry for formulating a coating material will support the zero waste policy and also added a value of byproduct.