Source: SEAMEO BIOTROP's Research Grant | 2017
Abstract:Postharvest quality improvement of Arabica coffee beans with various processing methods using two types of packaging materials to prevent the occurrence of ochratoxin A (OTA) producing fungi and OTA contamination have been conducted. Coffee beans were dried with three types of processing methods, i.e. natural, full wash, and semi wash processings. The beans were packed using two types of packaging materials, i.e polypropylene bag and polyethylene hermetic bag (4 kg/bag). They were then stored under warehouse conditions during 4 months of storage. Moisture content of coffee beans with natural processing were higher than that with full wash and semi wash processing. Grade of coffee beans in various treatments were still grade 1, but defective value of beans increased and attained maximum defective value for grade 1 (11). Taste of coffee beans in various treatments during 4 months of storage were still above total standard score for specialty grade ≥ 80. The highest total score was found in coffee bean with natural processing was packed in polyethylene hermetic bag (84). OTA producing fungi, Aspergillus ochraceus was only found in coffee beans with full wash and dry processing at the beginning of storage.Their population were relatively low < 3 cfu/g w.b. Population of Aspergillus niger of coffee beans with various processing was < 10 cfu/g w.b. The highest population of A. niger was found in coffee beans with semi wash processing. Aspergillus ochraceus and A. niger were also found in dried green beans with full wash processing, i.e. 13 and 10 cfu/g w.b. Although OTA producing fungi was found in coffee beans, but OTA content in all samples during storage were lower than limit detection of instrument (<1.85 ppb). At the beginning of storage, all samples were dominated by yeasts with their population 1.9 x 102 – 1.2 x 103 cfu/g w.b.