蓮霧果實寒害時乙烯釋放率及呼吸率之變化

The objectives of this study were to investigate the symptoms and index of chilling injury of wax-apple when wax it was subjected to low temperature. Black DiamondR wax-apple suffered chilling injury while it was stored at 1℃ for two days. Symptoms of injury were first appered as the day of storage increased. Sinking of the skin happened earlier than than the development of discoloration. The abnormal ethylene production had been found after stored at 1℃ for 3 days then back to room temperature. The ethylene peak was more apparent after storage for four days, and it was more and more increased with storage days. Therespiration rate of wax-apple stored at 1 and 15℃ was low than of at 25℃. But showed an abnormal respiration peak after stored at 1℃ for 3 days. The peak remined abnormally high after storing for 4 days at 1℃ and then back to room temperature. Theresults showed that the abnormal ethylene production and respriation are not suitable indices of chilling injury in Black DiamondR wax-apple.本試驗為探討黑鑽石蓮霧果實經低溫貯藏後乙烯釋放率、呼吸速率及果皮外觀顏色之發化。黑鑽石蓮霧經l℃貯藏2天即可能發生寒害，且隨貯藏天數增加，果皮寒害徵狀由小點凹陷發展為大塊陷斑且褪色情形愈趨嚴重，並且果皮凹陷之發生較果皮褪色為早。蓮霧果實經l℃貯藏3天回溫後即有乙烯釋放異常現象產生，貯藏4天後更為明顯，並且乙烯釋放高峰隨貯藏天數增加而有逐漸上升的現象。蓮霧果實於l及15℃『低溫貯藏期間呼吸率皆低量，且較25℃為低，經l℃貯藏3天回溫後即有呼吸高峰異常現象產生，貯藏4天回溫後呼吸率則無法降至正常範圍，並且最大呼吸峰於貯藏7天後出現，隨天數增加呼吸峰反為下降。因此乙烯釋放率及呼吸率之異常現象皆出現於寒害徵狀之後

荔枝果皮褐化與多酚氧化酵素及過氧化酵素之關係

The objectives of this experiment were to investigate the relationship between pericarp browning, polyphenol oxidase and peroxidase activity of litchi fruits, and hope to distinguish the importance role of two types of enzymes to litchi pericarp browning. Results showed that water loss of fruit mainly occurred. During pericarp browning of ‘Hei Yeh'litchi fruits, peroxidase activity of the peel was higher than the polyphenol oxidase activity, and showed a tendency to increase during storage. However, variations of polyphenol oxidase activity were not coincidental. Furthermore, when fruits at low humidity induced pericarp browning, the obvious increase phase of peroxidase activity was earlier than polyphenol oxidase. Therefore, it seemed that changes in the peroxidase activity were more significant than the polyphenol oxidase activity in respect of litchi pericarp browning.本試驗的目的在研究荔枝於採收後的貯藏期間，果實乾燥失水時，果皮內的多酚氧化酵素及過氧化酵素的活性變化情形，期能釐清此兩種酵素與荔枝果皮褐化上之相關性。結果顯示，隨著果實失水而褐化期間，果皮內的過氧化酵素活性均上多酚氧化酵素活性高，並且隨著貯藏時間其活性呈增加的趨勢而多酚氧化酵素活性則無一致的變化，此外，當貯藏於低濕下的果實發生明顯的果皮褐化時，其過氧化酵素活性顯著上升時期也比多酚氧化酵素早。因此，過氧化酵素活性表現比多酚氧化酵素活性，對荔枝果皮褐化影響較大

溫度對香菇太空包氣體組成及菌絲生長之影響

本試驗目的為觀察溫度對香菇太空包內氣體組成以及菌絲生長之影響，香菇太空包於各溫度中乙烯含量普遍低於0.4ppm，二氧化碳含量隨溫度升高而上升，氧氣則隨溫度升高而降低，25°C為香茹菌絲最適生長溫度，此溫度中菌絲僅需4週即可佈滿太空包，而6°C則需16週時間，30°C下菌絲幾乎不生長。The purpose of this study was to observe the effect of temperature on the gas composition is shiitake growth bags and the mycelium growth. The ethylene concentration in each shiitake growth bag under each temperature is generally lower than 0.4 ppm. Carbon dioxide concentration slowly increased as temperature increased. Oxygen slowly decreased as temperature increased. The temperature under which the shiitake mycelium filled the growth bags completely was 25℃. This process only took four weeks, but when the temperature was under 6℃, the shiitake mycelium took sixteen weeks to fill the bags. As the temperature reach 30℃, shiitake mycelium barely grew

甲殼素處理對芒果品質之影響

本試驗調查甲殼素處理對'聖心'、'愛文'及'金煌'芒果品質之影響。結果顯示凡經甲殼素處理的果實都能較對照組果實有較低的失重率，其中以2及3%甲殼素處理效果最顯著。甲殼素處理亦能改變果實內部氣體組成份，特別是1、2及3%甲殼素處理能使果實內部累積大量的二氧化碳及較少量的氧氣濃度。'金煌'芒果經甲殼素處理後能延後果實後熟，其中以2及3%甲殼素處理的果實會延緩其果皮及果肉顏色轉包，果肉軟化及澱粉轉化成糖。但是1、2及3甲殼素處理卻會使'聖心芒果果實內部累積高量的乙醛及乙醇，進而使果實產生異味。The objective of this study was to investigate the effect of chitosan coating on the quality of 'Sensation', 'Irwin' and 'Chinn Hwang' mangoes. Results indicated that the chitosan treated mango fruits tended to have a lower weight loss than the control fruits, while 2 and 3％ chitosan coating had remarkable effect in reducing weight loss. Chitosan coating also modified fruits'internal atmosphere, especially 1, 2, and 3％ chitosan coating can cause fruits internal accumulated considerable quantities odf carbon dioxide and lower level of oxygen concentration. Chitosan coating delayed the ripening of 'Chinn Hwang' mangoes, of which 2 and 3％ chitosan coating tended to delay the changes of peel and flesh color, fruits softness and changes of starch to sugar of 'Chinn Hwang' mangoes. However, 1,2, and 3％ chitosan coating caused substantial accumulation of ethanol and acetaldehyde in 'Sensation' mango and induced off-flavor

貯藏溫度及果實大小對‘富有’甜柿果實品質之影響

本試驗之目的在調查'富有'甜柿果實不同貯藏溫度及不同果實大小對果實貯藏品質之影響，以了解'富有'甜柿果實之最佳貯藏方式及適合貯藏果實大小，以減少貯藏期間果實損失之發生。結果顯示，'富有'甜柿果實在l℃下貯藏有較佳的貯藏品質，果實於貯藏4週後可維持較高硬度，貯藏壽命約4星期;而於3~15℃貯藏時，果實嚴重軟化喪失商品價值。因此，'富有'甜柿果實建議貯藏溫度為l℃。此外，本試驗將不同大小'富有'甜柿果實貯藏於l℃下，結果顯示，以225-265g之小型果實硬度維持63.8N，l℃貯藏4週後以小果有較佳貯藏品質。The objectives of this study were to investigate the effects of temperatures and fruits size on the storage life and fruit quality of the 'Fuyu' persimmon with a view to defining the best storage temperature and condition, reducing chilling injury and fruit softness, and improving the quality as well as commercial value of the fruits. The results indicated that persimmon fruits, which were stored at 6-15℃ for 4 weeks, developed the symptoms of translucent peel and softening flesh soon after returning to the room temperature. Softness also occurring in fruits stored at 1 or 3℃, but the damage was less extensive. It is concluded that suitable storage temperature for persimmon cv. 'Fuyu' should be below 1℃. In addition, the smaller fruits(225-263 g)showed good quality and high firmness after storage for 4 weeks at 1℃ and shelved at 25℃ for 3 days

Comparative Studies of Fruit Softening in Persimmon (Diospyros kaki Thunb. cv. 'Hirataneanshi') in Relation to Different Methods for Removal of Astringency and Temperature

本試驗比較酒精脫澀法、二氧化碳脫澀法及石灰懸浮液脫澀法對‘平核無’柿果脫澀後軟化之影響。以二氧化碳脫澀法和酒精脫澀法處理之柿果在軟化速度上並無差異，但石灰懸浮液脫澀法處理者則能保持較高之硬度。‘平核無’柿果以二氧化碳脫澀時，其脫澀速率隨溫度增加而加速，在35℃下需2日才達可食用狀態，而30℃下則需3日、25℃下則需5日，而20℃者在5日內仍無法達可食狀態；在硬度方面，除35℃外，30°、25°及20℃處理者，在脫澀完成後皆有軟化之現象。此外，本試驗亦進行二氧化碳處理時間及濕度對‘平核無’柿果脫澀及軟化之影響，其中以30℃處理二氧化碳2日，再降溫至15℃放置1日，可得較佳之硬度；而以此法脫澀完後之柿果，進行貯藏溫度試驗，貯存溫度以0℃較佳，而以EVA膜逐果包裝有減輕軟化之效果，但所有貯藏後之柿果在櫥架上（25℃，2日）皆有嚴重軟化現象。 Fruit quality and softening of persimmon ('Hiratanenshi') were studied following three treatments (ethanol treatment, carbon dioxide treatment, and calcium oxide suspension dipping method) for removal of astringency. There was no significant difference in flesh softening of fruits treated with carbon dioxide and ethanol. Fruits treated with carbon dioxide softened quickly, but the firmness flesh of fruit treated with calcium oxide suspension slowly declined. The effect of temperature on 'Hiratanenshi' fruits treated with carbn dioxide was examined during deastringency at various temperature ranging from 20 to 35℃. The rate of decrease of astringency was high with higher temperature. The times required to reach under 2 of astringent index were 2, 3, 5 and more than 5 days at 35°, 30°, 25° and 20℃, respectively. A significant decrease in fresh firmness occurred when the fruits had been removed of astringency with carbon dioxide at 30°, 25° and 20℃, but except 35℃. Our results showed that carbon dioxide treatment of 'Hiratanenshi' fruits at 30℃ for 48 hr followed by storage in air at 15℃ for 24 hr produced de-astringent fruit of excellent quality without abnormal softening. However, the dc-astringent fruits could be stored at 0℃ to extend the storage life up to 1 to 2 weeks and storage of fruits wrapped individual unit with ethylene vinyl acetate film at 0℃ which improved the storage life of fruits, but the fruits appeared to became serious softening and water-logged in the flesh region when those were transferred to 25℃ for 2 day

Astringency Removal and Softening as Related to Temperature during the Deastringency by Ethanol in “Hiratanenashi” Persimmon Fruits

本試驗以本省生產之’平核無’柿果為材料，進行酒精脫澀之試驗。酒精用量每公斤柿果至少4ml，效果較佳。在30℃下，酒精處理時間達16小時即足以誘發柿果脫澀。果實以酒精脫澀之速度隨溫度增加而加速，在25℃下需4日；在30℃下需3日；而在35及40℃下則只需2日即可完成脫澀。脫澀時之軟化現象，隨脫澀溫度增加而減緩；另外，在脫澀前以48.5℃熱風處理柿果3小時，亦有減緩脫澀後的軟化現象。 The disappearance of astringency was studied in ‘Hiratanenashi’ persimmon (Diospyros kaki Thunb.) fruits which had been treated with ethanol. For adequate astringency removal and fruit quality the optimum ethanol concentration was 4 ml ethanol per kg fresh fruit at 30℃. Astringency disappearance only when fruit had been in ethanol vapor for at least 16h. The decrease in astringency was effected by temperature. The rate of decrease was high with higher temperatures. The times required to reach completely deastringency were 4, 3, 2 and 2 days at 25°，30°，35° and 40℃, respectively. A gradual decrease in flesh firmness during deastringency, and there were significant differences in the rate among the various holding temperature ranging from 25° to 40℃. The rate of decrease in firmness was loww with higher temperatures. In addition, the decrease of firmness was inhibited by the fruits treated with high temperature force air (48.5℃) for 3h before ethanol deastringent treatment

Effect of Maturity on the Quality of Harvested Passion Fruits (Passiflora edulis Sims.)

The purpose of this study was to examine how maturity of passion fruits influence the length of storage life and quality after being stored of ‘Tainung NO.1' passion fruits. After the half red color ‘Tainung NO.1' passion fruits were plucked, they would continue to change color. Furthermore, after seven days of ‘Tainung NO.1' passion fruits plucking from trees, their TSS/TA would increase to a similar degree of more mature passion fruits, and they would not have a shortage of bad flavor like low mature passion fruits. Therefore, for the purpose of storage or long distance transfer, it has better to choose the half red color ‘Tainung NO.1' passion fruits. TSS=total soluble solid; TA=titratable acidity.本試驗主要為了了解成熟度對於’台農一號’百香果貯藏壽命和貯藏後果實品質之影響。於自然落果前先行摘取果皮半紅綠之’台農一號’百香果，果實於採後能夠繼續轉色，果汁糖酸比於採收7日後可以上升至和高成熟度相似，且無低成熟度果實果汁風味不佳之缺點。因此若以貯藏或長程運輸為目的者，宜採用果皮半紅綠之果實

The Investigation of Phenylalanine, Glucosinolate, Benzylisothiocyanate (BITC) and Cyanogenic Glucoside of Papaya Fruits (Carica papaya L. cv. ‘Tainung No. 2’) under Different Development Stages between Seasons and Their Correlation with Bitter Taste

Papaya fruit is one of economic crops in Taiwan, mostly eaten as table fruits. In some Asian countries, unripe papaya fruit is eaten as salad and this led to trends in Taiwan as well. However, unripe papaya fruit may taste bitter during cool seasons. Glucosinolate and cyanogenic glucoside are among the substances that cause bitter taste in many plants, which can also be found in papaya. However, there is still no report about the relationship between seasons and bitter taste in papaya fruits. Thus, the purpose of this study is to investigate the glucosinolate biosynthesis and its correlation between bitterness intensity during cool and warm seasons. The bitterness intensity was highest at the young fruit stage and decreased as it developed. In addition, the bitterness intensity in cool season fruits is higher than in warm season fruits. Cyanogenic glucoside and BITC content showed negative correlation with bitterness intensity (r = −0.54 ***; −0.46 ***). Phenylalanine showed positive correlation with bitterness intensity (r = 0.35 ***), but its content did not reach the bitterness threshold concentration, which suggested that phenylalanine only acts as cyanogenic glucoside and glucosinolate precusors. Glucosinolate content showed positive correlation with bitterness intensity at different developmental stages (r = 0.805 ***). However, the correlation value in different lines/cultivars decreased (0.44 ***), suggesting that glucosinolate was not the only substance that caused bitter taste in immature papaya fruits