|Obenland, David - Dave|
|Arpaia, Mary Lu|
Submitted to: Postharvest Biology and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/20/2013
Publication Date: 8/1/2013
Citation: Obenland, D.M., Collin, S., Sievert, J., Arpaia, M. 2013. Mandarin flavor and aroma volatile composition are strongly influenced by holding temperature. Postharvest Biology and Technology. 82:6-14. Interpretive Summary: Mandarins are increasing in acreage planted but often suffer from poor flavor following storage. To enhance understanding of the effect of temperature on the storage disorder ‘W. Murcott’ mandarins were stored for either 6 weeks at a continuous 5 ºC or held at 20 ºC for either 1 or 2 weeks following 0, 2 or 4 weeks of 5 ºC. Flavor was unaffected if the fruit was kept at 5 ºC but rapidly worsened in the fruit held at 20 ºC. Flavor loss increased as the duration of cold storage prior to the warm temperature holding period was lengthened. These effects were also observed in three of the four other mandarin varieties tested. Increases in aroma compounds were closely linked to the development of off-flavor, while soluble solids concentration (sweetness) and titratable acidity did not consistently change as a result of temperature. The increases in aroma compounds were apparent within one day of transferring the fruit from 5 ºC to 20 ºC. This study suggests that it may be possible in many cases to prevent flavor loss in mandarins during storage by maintaining the fruit at a cold temperature ranging from 5 ºC to 10 ºC.
Technical Abstract: Mandarin flavor quality often declines during storage but the respective contributions to the flavor disorder of warm versus cold temperature portions of the storage regime were unknown. To determine this ‘W. Murcott’ mandarins were stored for either 6 weeks at a continuous 5 ºC or held at 20 ºC for either 1 or 2 weeks following 0, 2 or 4 weeks of 5 ºC storage. Sensory quality as measured by likeability was maintained throughout the 6 week storage when the fruit were kept at 5 ºC, but rapidly declined upon moving fruit to 20 ºC. Flavor loss increased as the duration of cold storage prior to the warm temperature holding period was lengthened. The beneficial effect of maintaining mandarins in cold storage was also observed in three of the four other varieties where there was flavor quality loss during storage at a warmer temperature. Soluble solids concentration (SSC) and titratable acidity (TA) were relatively unchanged by holding at 20 ºC, but aroma volatiles, with alcohols and ethyl esters being of the greatest importance, were greatly enhanced in concentration and are the likely cause of the off-flavor. The increases in aroma volatile concentration were apparent within one day of holding the fruit at 20 ºC, indicating the need to carefully control postharvest storage temperatures. This study suggests that it may be possible in many mandarin varieties to prevent losses in mandarin flavor quality by maintaining the fruit at a cold temperature (5 to 10 ºC) following packing and until the time of consumption.