Proceedings 30 th Meeting

Transcription

1 Proceedings 30 th Meeting , Bonn, Deutschland Persimmons - UNECE standard and explanatory brochure Ulrike Bickelmann (BLE) BLE, IAT

2 1 Persimmons - UNECE standard and explanatory brochure Ulrike Bickelmann In 2012 and on request of Tajikistan, the UNECE Specialized Section on the Standardisation of Fresh Fruit and Vegetables did start to develop a standard for persimmons and in 2013 to develop a respective explanatory brochure. In November 2013, a working group met in Valencia (Spain) and in October 2014 in Faenza (Italy) to select samples that could illustrate the draft standard and draft brochure. The opportunity of being mid-season in two different production areas was ideal to check whether the draft standard was practice-oriented. After two meetings, the working group did submit a proposal to slightly amend the draft standard or standard recommendation and a fully illustrated draft explanatory brochure. In April 2015, the UNECE Specialized Section will decide and possibly approve standard and brochure. The standard recommendation and the draft explanatory brochure are available as in-session documents at the UNECE website: unece.org/index.php?id=38235#/ The participants of the International Meeting on Quality Control of Fruit and Vegetables will have the unique opportunity to discuss the standard recommendation and draft brochure and to assess the samples presented. Comments are welcome. Below, not the full standard but special characteristics, defects and provisions for persimmons are presented. Definition of produce Persimmons are the fruit of the species Diospyros kaki L. The varieties of persimmons are classified in four groups: Varieties of the PCNA-Group (Pollination Constant Non-Astringent) produce fruit that are non-astringent at harvest. Hard-ripe fruits are edible at harvest but may also be consumed in the jelly-soft stage. Important varieties are Fuyu (Fuyugaki) and Jiro. Varieties of the PVNA-Group (Pollination Variant Non-Astringent) produce non-astringent fruits when pollinated and a few seeds are developed. The flesh is brown and often rich in dark spots. Parthenocarpic, i.e. seedless fruits become edible after natural softening or artificial removal of astringency. An important variety of this type is Kaki Tipo (Loto di Romagna) produced e.g. in Italy. Varieties of the PCA-Group (Pollination Constant Astringent) produce astringent fruits at harvest, regardless of the presence of seeds. The flesh is light-coloured. Fruits become edible after natural softening or artificial removal of astringency. An important variety of this type is Rojo Brillante produced e.g. in Spain. Varieties of the PVA-Group (Pollination Variant Astringent) produce astringent fruits, regardless of pollination. Pollination removes the astringency around the seeds only, where there are brown spots. The number of seeds is irrelevant for fruit astringency. In these varieties the fruit may be consumed in the jelly-soft stage, or firmripe fruit may be cut if the flesh is brown the fruit is edible, if the fruit shows no brown spots the fruit is not edible or the astringency must be artificially removed. An important variety of this type is Triumph produced e.g. in Israel. Minimum requirements Intact, with calyx attached, which may be with or without peduncle, the calyx may be brown and dried: Persimmons will rarely lose their calyx naturally. The peduncle is cut off when the fruits are clipped from the tree or after harvest to avoid that fruit could damage any neighbouring fruits. During shelf life the calyx dries out and becomes dark brown which is not considered to be a defect. In the calyx area, sometimes deep cracks appear and damage the fruits. Sound: Persimmons are prone to rotting, mould and physiological defects. Clean: Fruits with slight traces of dust in the calyx or on the fruit surface are regarded as being practically clean and are allowed in all classes. Any dust and soiling exceeding this limit is not allowed. Pests: Fruits affected by an occasional insect or mite which are mainly sitting under the ca- BLE, IAT

3 Persimmons - UNECE standard and explanatory brochure 2 lyx are regarded as being practically free from pests and are allowed in all classes. Any colony of insects or mites is not allowed. Damages caused by pests and affecting the flesh are not allowed. All other defects caused by pests are assessed within the limits for skin defects. Maturity requirements Persimmons are climactric fruits. In order to guarantee a satisfactory ripening, fruits must not be harvested too early, i.e. they must have reached the size characteristic for the variety and they must be sufficient mature. Fruits of the variety Rojo Brillante are sufficiently mature when at least one third of the fruit surface is turning yellow. At the beginning of the season, fruits are harvested in this stage. Later in the season, fruits are more yellow or even orange when picked. Classification Persimmons are classified into three classes. Shape: Fruits of Extra class should hardly deviate from the varietal characteristics. In Class I slight defects in shape and in Class II defects in shape are allowed. Misshapen fruits are allowed within the tolerances only. Colouring: The variation in colour due to ripening is not regarded as a defect. On the tree, persimmons are exposed to sunlight. Defects in colouring due to sun are accepted within the classes: very slight defects in Extra Class, up to 1/8 of the surface may be affected by slight defects in Class I and up to ¼ of the surface in Class II. Skin: In persimmons skin defects develop depending on variety and growing conditions. Fruits of the variety Rojo Brillante show corky lines running down from the calyx to the pistil end. The UNECE working group proposes the following limits: in Class I the total length of those lines should not exceed the distance between the pistil and the calyx end; in Class II it should not be more than twice this distance. Skin defects e.g. caused by rubbing and appearing more spread should not exceed 1/16 in Class I and 1/8 in Class II as proposed by the UNECE working group. In no case, these defects should show cracked corkiness. These limits could also be applied on cracks caused in varieties such as Kaki Tipo under humid-warm growing conditions. Bruises: In persimmons of Class I slight bruises not exceeding 2 cm 2 in total are allowed; in Class II not more than 3 cm 2. When assessing bruises, it should be taken into account that the flesh in Classes Extra and I must be perfectly sound, while in Class II it must be free from major defects. Thus, in Class I bruises may be slightly discoloured and in Class II they may be slightly soft but not too deep. Calyx: In Class I the calyx may be slightly damaged and in Class II it may be damaged. Internal discolouration: As persimmons contain tannins, the flesh may be affected by brown discolouration. This discolouration naturally develops after seed set or is characteristic in certain varieties. Taste is not affected when the flesh is discoloured. But this internal discolouration can also be an indication of inappropriate handling. After the astringency has been removed, fruits are sensitive to shock. Thus, fruits must be graded, sorted and packed very carefully. In case of rough handling, internal discolouration will develop. UNECE proposes that internal discolouration should not exceed 1/3 of the total cross-section in Class I and 1/2 in Class II. Fruits developing this internal discolouration under the skin only should be assessed accordingly. Advice: Internal discolouration may intensify along the marketing chain, i.e. become darker, but the area affected will not increase. This is why the assessment takes into account the area affected but not the intensity of discolouration. Sizing Persimmons may be sized by weight, diameter of the equatorial section, or by count. A minimum size is fixed and must be respected in all Classes. Uniformity in size is obligatory in Classes Extra and I only. In case of sizing by diameter or count, the maximum difference in size in a package is restricted to 20 mm. In case of sizing by weight, a sizing table must be respected. Tolerances In persimmons the tolerances follow the UNECE standard layout. BLE, IAT

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10 Publisher Federal Office for Agriculture and Food [Bundesanstalt für Landwirtschaft und Ernährung] Deichmanns Aue Bonn Germany Internet: Phone: +49 (0) Fax: +49 (0) Editor Division 223 The Proceedings of the International Meeting Quality Control of Fruit and Vegetables are copyrighted. No part of these Proceedings may be reproduced, copied, translated, electronically stored, processed, duplicated or disseminated without the written permission of the Federal Office for Agriculture and Food. The proceedings is as of Spring 2015 Meeting 30th International Meeting Quality Control Fruit and Vegetables, 9 11 March 2015, Bonn, Germany BLE, IAT