外銷椪柑、桶柑與柳橙之採收、檢疫處理與貯、運、銷技術方略

Abstract

綜合近十餘年來對台灣產椪柑、桶柑及柳橙之採收成熟度、貯藏條件與貯藏壽命、檢疫處理及催色要領等研究成果，提供有關外銷柑桔之採收處理與貯、運、銷技術方略要點如次： 1. 椪柑、柳橙與桶柑依序自11 月中旬、12 月中旬與1 月中旬起約半個月內是採收外銷果最適期。 2. 適宜之貯、運條件為15℃，90~95%相對濕度。椪柑有2~3 個月，柳橙與桶柑有3~5 個月的安全貯、運、銷期間。 3. 須經低溫檢疫處理之外銷柑桔採後愈快低溫處理愈好；延遲處理則較易受低溫傷害。椪柑最好在採後5 日內，桶柑與柳橙在10 日內開始處理。早處理者處理後尚有30~45 日的貯、運壽命。 4. 低溫檢疫處理造成果實傷害之嚴重性因生產年份與供果園而異；宜注意各年之狀況並慎選供果園。 5. 低溫檢疫處理傷害之果實置15℃五日後即易識別剔除；因此可考慮在15℃貯放5 日後選別包裝。 6. 桶柑及柳橙可耐高溫檢疫處理；椪柑則易發生熱傷害。 7. 早採半黃半綠的椪柑置15℃最快完全轉色；需時20~25 日。用乙烯催色則可加快10 日。 8. 趕早輸日之椪柑若在11 月20 日左右採收，速經低溫檢疫處理後在15℃運銷，12 月20 日之前可上市金黃色的果實。若在採後或檢疫處理之後速用乙烯催色，轉色更快。 Based on the results of a series of research on the maturity, storage conditions and storability, fruit fly quarantine treatments, and degreening methods for major Taiwan citrus, i.e. ‘Ponkan’ mandarin, ‘Liucheng’ orange, and tankan, several key technologies and strategies for harvesting, handling and marketing the fruit targeted for export are summarized as follows. (1) Optimum harvesting periods of ‘Ponkan’, ‘Liucheng’, and tankan for export are about half-month beginning mid-November, mid-December, and mid-January, respectively. (2) Optimum condition for storage and transportation of the fruit is 15℃, 90~95% relative humidity; safe storage periods are 2~3 months for ‘Ponkan’ and 3~5 months for ‘Liucheng’ and tankan. (3) If low-temperature quarantine treatment is required, the treatment should begin as soon as possible, preferably within 5 days after harvest for ‘Ponkan’ and within 10 days for ‘Liucheng’ and tankan; early-treated fruit has a storage and marketing life of 30~45 days, but late treatment encourages low-temperature injury. (4) The severity of rind injury induced by low-temperature quarantine treatment varies with harvesting years and orchards; careful evaluation and orchard selection are advisable. (5) Most of the fruits injured by low-temperature quarantine treatment are discernible and can be sorted out 5 days after being kept at 15℃. (6) ‘Liucheng’ and tankan can tolerate high-temperature quarantine treatment, but ‘Ponkan’ cannot. (7) Early harvest half-green ‘Ponkan’ turns yellow most rapidly, within 20-25 days, at 15℃; coloration can be accelerated for about 10 days by ethylene-degreening treatment. (8) ‘Ponkan’ for early season Japanese market can be harvested on around November 20th, quickly treated with low temperature for quarantine, shipped at 15℃, and arrive golden colored before December 20th, just make for Christmas; earlier supply of well-colored ‘Ponkan’ is possible by employing ethylene degreening.