Indicators of plum maturity: When do plums become tasty?

Abstract The good taste of European plums ( Prunus domestica L.) was the main focus of this research. During three fruiting seasons, indicators of ripening stages (peel and flesh colour, soluble solids content—SSC and firmness) were measured and eating quality sensoryly evaluated on four plum cultivars (‘Haganta’, ‘Jojo’, ‘Stanley’ and ‘Toptaste’). Measurements were performed during the final 4 to 7 weeks of ripening at 3(4)- or 7-day intervals to identify the ripeness stage at which plums become tasty at optimal texture. The results indicated a high variability in pomological characteristics among different cultivars and growing seasons, especially at the ripening stage when eating quality improves. This ripening stage, when sensory quality scores shift from 2.5 on a five-step scale (lower limit taste stage, LLTS) was the start of the potential picking window (PPW), which was further analysed in detail. PPW ended when the estimated eating quality of plums exceeded a score of 4. During PPW, a change of firmness is the only useful indicator of plum maturity. Plums became tasty when they satisfied conditions in the following order: (1) fruit skin completely coloured; (2) flesh colour changed from green into characteristic colour for cultivar; (3) fruit firmness equals 15 ± 2 N.

[1]  C. Crisosto,et al.  Increasing 'Blackamber' plum (Prunus salicina Lindell) consumer acceptance , 2004 .

[2]  M. Hernández,et al.  Physicochemical and nutritional properties and volatile constituents of six Japanese plum (Prunus salicina Lindl.) cultivars , 2009 .

[3]  R. Leardi,et al.  Prediction of the optimum harvest time of ‘Scarlet’ apples using DR-UV–Vis and NIR spectroscopy , 2012 .

[4]  P. Casquero,et al.  Site and fruit maturity influence on the quality of European plum in organic production , 2009 .

[5]  V. Usenik,et al.  Phytochemicals in fruits of two Prunus domestica L. plum cultivars during ripening. , 2013, Journal of the science of food and agriculture.

[6]  P. Casquero,et al.  Influence of Harvest Dates on Quality, Storage Capacity and Sensory Attributes of European Plum cv. Green Gage , 2009 .

[7]  R. Infante,et al.  Non-destructive monitoring of flesh softening in the black-skinned Japanese plums ‘Angeleno’ and ‘Autumn beaut’ on-tree and postharvest , 2011 .

[8]  R. Infante,et al.  Instrumental and sensory evaluation of eating quality of peaches and nectarines. , 2012 .

[9]  C. Ledbetter,et al.  Development of volatile compounds during fruit maturation: characterization of apricot and plum * apricot hybrids , 1997 .

[10]  R. Tharanathan,et al.  Fruit Ripening Phenomena–An Overview , 2007, Critical reviews in food science and nutrition.

[11]  V. Usenik,et al.  Sweet cherry pomological and biochemical characteristics influenced by rootstock. , 2010, Journal of agricultural and food chemistry.

[12]  P. Casquero,et al.  Post-harvest quality of ‘Green Gage’ European plum in integrated production: effects of year and fruit maturity , 2010 .

[13]  V. Usenik,et al.  Anthocyanins and fruit colour in plums (Prunus domestica L.) during ripening. , 2009 .

[14]  Y. Gogorcena,et al.  Analysis of phenotypic variation of sugar profile in different peach and nectarine [Prunus persica (L.) Batsch] breeding progenies , 2009 .

[15]  A. Kader,et al.  Fruit ripening and quality , 1986 .

[16]  D. Valero,et al.  Changes in physicochemical and nutritive parameters and bioactive compounds during development and on‐tree ripening of eight plum cultivars: a comparative study , 2008 .

[17]  António S. Barros,et al.  Search for suitable maturation parameters to define the harvest maturity of plums (Prunus domestica L.): A case study of candied plums , 2009 .

[18]  D. Slaughter,et al.  Relationship between nondestructive firmness measurements and commercially important ripening fruit stages for peaches, nectarines and plums , 2007 .

[19]  R Core Team,et al.  R: A language and environment for statistical computing. , 2014 .

[20]  V. Usenik,et al.  Quality changes during ripening of plums (Prunus domestica L.) , 2008 .

[21]  Adel A. Kader,et al.  Flavor quality of fruits and vegetables , 2008 .

[22]  P. Casquero,et al.  Harvest parameters to optimise storage life of European plum ‘Oullins Gage’ , 2009 .

[23]  P. Holford,et al.  Ripening behaviour and responses to propylene in four cultivars of Japanese type plums , 1997 .

[24]  Scott Johnson,et al.  Factors in fresh market stone fruit quality , 1995 .

[25]  A. Khan,et al.  Physiology of plum fruit ripening. , 2010 .

[26]  K. Theron,et al.  Volatile dynamics during maturation, ripening and cold storage of three Japanese plum cultivars (Prunus salicina Lindl.) , 2012 .