1、INTERNATIONAL STANDARD IS0 7482-l First edition 1998-06-o 1 Raw goat skins - Part 1: Descriptions of defects Peaux brutes de caprins - Partie I: Descriptions des dbfauts Reference number IS0 7482-1 :I 998(E) IS0 7482-l : 1998(E) Foreword IS0 (the International Organization for Standardization) is a
2、worldwide federation of national standards bodies (IS0 member bodies). The work of preparing International Standards is normally carried out through IS0 technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented
3、 on that committee. International organizations, governmental and non- governmental, in liaison with ISO, also take part in the work. IS0 collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards ad
4、opted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard IS0 7482-1, was prepared by Technical Committee ISOmC 120, Leather, Subcommittee S
5、C 1, Raw hides and skins, including pickled pelts. IS0 7482 consists of the following parts, under the general title Raw goat skins: - Par? 1: Descriptions of defects - Pat? 2: Guidelines for grading on the basis of mass and size - Part 3: Guidelines for grading on the basis of defects 0 IS0 1998 Al
6、l rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. International Organization for Standardization Case
7、postale 56 l CH-1211 Geneve 20 l Switzerland Internet iso iso.ch Printed in Switzerland ii INTERNATIONAL STANDARD 0 Iso IS0 7482-l : 1998(E) Raw goat skins - Part 1: Descriptions of defects 1 Scope This International Standard describes the defects which may occur on raw goat skins (see note 1). It i
8、s applicable to fresh and cured (air dried, wet salted or dry salted) goat skins. NOTE 1 - Certain defects, which are not defined in this standard, may appear only during or after the tanning process, without there being any indication of their presence on the raw skin. 2 Terms Relating to Presentat
9、ion of Trim 21 I Folded skins Skins without head, without teats, shanks cut short, tail completely emptied, presented folded along the the line of the backbone in the centre. 2.2 Open (flat) skins Skins without head, without teats, shanks cut short, tail completely emptied, presented flat, with the
10、line of the backbone in the centre. 2.3 Sleeve skins Skins without head, without teats, with legs cut short, tail completely emptied, presented as a sleeve, hair to the inside, folded along the line of the backbone. 3 Terms Relating to Defects in Goat Skins The defects defined in this standard are d
11、ivided into three categories : a) Ante-mortem defects; b) Post-mortem defects; and c Preserving defects. IS0 7482-l :1998(E) 3.1 Ante-mortem defects 3.1 .l Ecchymosis Bruise on the flesh side of the skin, varying from dark red to brown, caused by sub-cutaneous bleeding, especially if the animal has
12、been struck by a blunt object or if parts of the coat have been roughly plucked before slaughter. 3.1.2 Fire-marks Goat skins deteriorate in quality due to fire-mark. This is a man-made defect. Fire-mark is generally inflicted in different parts of the body with a view to cure some aliments or to in
13、dicate ownership of the animal. In raw skins, the defect is readily seen on the grain side. 3.1.3 Grain damage All visible and permanent alterations on the grain side of the skin, whatever their nature or origin (for example, wounds, scars, abscesses, rubbing of the shoulders or groin). 3.1.4 Greasy
14、 skin Skin in which the histological structure of the dermis is abnormally loose due to the penetration of grease. This state is revealed when the grease migrates due to localised heating after drying. After tanning, this may also result in an empty skin or a hollow skin, and can give rise to an alt
15、eration in the mass/surface ratio. 3.1.5 Pox marks Hard, circular lesion resulting in scar marks on the grain and opaque marks (due to the pus formed) on the flesh side of the skins, Pus in pox marks is also visible on the flesh side of the dried goat skins specially of African origin. 3.1.6 Ringwor
16、m , Disease caused by fungal species of two genera Microsporum and Trichophyfon mostly in goat skins. The lesions appear as raised round, crusty patches. Ringworm infections result in loss of hair in the goat skins. The incidence of ringworm affected skin is insignificant. IS0 7482-l :1998(E) 3.1.7
17、Skin infested with Ectoparasites 3.1 J.1 By Demodex caprae Goat skins are greatly affected by Demodex caprae causing Demodectic Mange (Follicular Mange). Nodules are visible on both the grain and flesh sides of goat skins. These mites may appear in : . 0 nodular forms; . . IO squamous forms; and . .
18、 . Ill) acute forms Raised nodules of varying size (several mm to 2 cm) can be seen on the flesh side of the skins. The small nodules are not altered by beamhouse operations and show up on the tanned skin in hardening of the tissues. On the other hand, if they are larger than 1 cm, they can form a p
19、it or hole by splitting the grain. 3.1.7.2 By lice Because of the irritation caused by the biting or sucking type of lice, the animals scratch the affected parts of the body which leads to wounds and bruises. Lice species belonging to the genera Linognathus are common to goat. Goat are also affected
20、 by biting lice (Damalinia or Bovicola spp.). Skins infested with lice (Linognathus stenopsis, Order anoplura) show transparency. 3.1.7.3 Psorop tic caprae Psoroptic mange defects in goat skins are caused by Psoroptes caprae. It is a seasonal defect and appears during rainy season. The lesions appea
21、r as small hard pustular nodes and are covered by long hair. After liming, the nodes are removed leaving a depression on the grain particularly on both sides of backbone. In finished leather the defect appears on the grain as innumerable pin prick marks on both sides of the backbone. 3.1.7.4 Sarcop
22、tes scabiei Sarcoptic mange is caused by Sarcoptes scabiei mites burrow into the sub- stance of the skins of goat causing galleries. Marked thickening and wrinkling of the skin takes place associated with the formation of scab as well as bald patches. Grain surface of the leather becomes rough showi
23、ng crisscross tunnels. 3.1.7.5 By ticks Skin showing considerable hardening of the tissue caused by the bites of parasites called ticks, together with the presence of their discharge in the coat and subsequently leading to pits on the grain surface of tanned skins. IS0 74821:1998( E) IS0 Ticks affec
24、t skin quality to a considerable extent. Ticks responsible for tick damage though belong to various genera like Ixodus, Haemophysalis, Der- macentor, Hyalomma, Boophilus and RI-ripicephalus, the most common live stock ticks responsible for damages in goat skins belong to the general Hyalom- IT) and
25、Boophilus. They leave scar mark on the grain side of finished leather. Ticks can also leave holes in the skins and remains of ticks can sometimes be found. 3.1.7.6 By warbles Skin on which holes or nodules can be seen on the flesh side caused by the migration of hypoderma crossi or hypoderma actaen
26、larvae (Order Diptera ), Extent of damage caused by warbles may be severe. 3.1.8 Thin skin Skin in which the quality of the fibres constituting the tissue is rendered defective by an abnormal thinning in the weeks immediately preceding slaughter of the animal because of any illness and/or malnutriti
27、on. After tanning it produces an empty skin or a hollow skin. 3.2 Post-mortem defects 3.2.1 Butcher strain Defects caused by improper flaying resulting in grain damage and/or reduction in tensile strength of leather produced from the same. 3.2.2 Deformation Pattern which gives the skin an irregular
28、shape and causes tear during process- ing. It includes over trimming of the neck or feet and/or poor off-take of the skins which deforms the skin and leads to a loss in surface area. Deformation is also caused when the backbone line forms a diagonal of the skins. 3.2.3 Extras Any useless parts attac
29、hed naturally to the skin (horns, hooves, ears, etc.) and which, by their mass, falsify the yield of the batch. NOTE 2 - This yield can also be falsified by an excess of salt or preserving product. IS0 7482-l : 1998(E) 3.2.4 Flay cuts Accident in the skinning resulting from the knife or skinning too
30、l completely piercing the skin. 3.2.5 Freezing Degradation may be caused by lowering in temperature to sub-zero for storage. This hardening of the skin is liable to cause splitting of the grain if the skin is incorrectly dried. 3.2.6 Nicking A score produced in the dermis by the knife or flaying too
31、l, without complete perforation. 3.2.7 Patches of grease or flesh All pieces of fat or flesh which remain attached to the skin and cause a defect in the grain by preventing correct penetration or dehydration of the skin. Moreover, these patches can conceal a skinning defect such as a nick. 3.3 Prese
32、rving and storage defects Raw goat skins can be preserved using various methods. Depending on the method used, raw goat skins can be presented in the form of skins preserved in the dry state (air dried skins) or in the salted state (wet salted skins) or in the dry salted state (dry salted skins). Ea
33、ch of these states has corresponding charac- teristic defects. 3.3.1 Dry salted state 3.3.1.1 Defects caused by mineral salts Discolouration of the grain or flesh side of the skin and alteration of the structure of the dermis caused by the combined action of mineral salts, in particular those derive
34、d from iron, and the moisture in the ambient air. (These defects are especially noted on skins preserved for a long time). 5 IS0 7482-l : 1998(E) 3.3.2 General case 3.3.2.1 Putrefaction (Decay) Partial decomposition of the skin revealed in a premature hair slip, which can go as far as the rotten ski
35、n stage. Putrefaction of the flanks, shanks or butt results due to the fact that, in these areas, the skin has not been suitably opened and not stretched from the start of drying. Wetting during storage, slow drying, piling without cooling and case hardening also result in putrefaction. 3.3.3 Raw dr
36、y state 3.3.3.1 Blood stains Presence of congealed blood visible on the flesh side of the skin, which can lead to staining after tanning,. 3.3.3.2 Case hardening Decaying of the internal layers of the skin, caused by the surface being dried too rapidly, thus preventing the dehydration of the deeper
37、layers of the skin; this can lead to a separation of the external layers 3.3.3.3 By Dermestes Damage caused on the flesh side of the skin by Dermestes larvae eating the dermis, thus reducing the strength of the skin and altering the regularity of its thickness. This may possibly lead to damage on th
38、e grain side of the skin and even holes. 3.3.3.4 Folding crack When skins are sun dried, they may produce grain crack during folding. 3.3.3.5 Glossiness Hard and brittle form, of glossy or shiny appearance, taken on by the skin following localised defective drying, most frequently in the sun, In the
39、 case of kid skins, this defect can be caused by excessive tension applied to the skin during frame drying. IS0 7482-l :1998(E) 3.3.3.6 Mildew Visible development of saprophytic fungus on the flesh side of the skin, promoted by prolonged storage in too humid an atmosphere ; it can also result in an
40、alteration in the grain on the tanned skin. 3.3.3.7 Sticking Sticking of the skins, flesh side to flesh side, from the start of drying and causing decay. 3.3.3.8 Strain mark Defect caused by poor handling of dry skins. 3.3.4 Salted state 3.3.4.1 Red heat Surfaces coloured red or violet (see NOTE 3),
41、 in the latter case often accom- panied by an exudation. NOTE 3- These are usually associated with the growth of halophilic bacteria (red heat). The development of this problem can be avoided by the inclusion in the curing salt of suitable preservatives. 3.3.4.2 Salting defect Putrefaction from inadequate salting or loss of salt because of storage in the open during wet weather. This page intentionally left blank This page intentionally left blank IS0 7482=1:1998(E) ICS 01.040.59; 59.140.20 Descriptors: hides, goats, raw materials, defects, vocabulary. Price based on 7 pages
