DRAFT UGANDA STANDARD  
  DUS 1866  
First  Edition  
2018 -mm-dd 
 
 
 Refe rence number  
DUS 1866: 201 8 
© UNBS 2018   
  
Edible  natural c asing s — Sausages  —Specification  
 DUS 1866 : 2018  
ii © UNBS 2018  – All rights reserved  
 Compliance with this standard does not, of itself confer immunity from legal obligations  
A Uganda Standard does not purport to include all necessary provisions of a contract. Users are 
responsible for its  correct application  
© UNBS 2018   
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, including photocopying and microfilm, without prior written 
permission from UNBS.  
Requests for permission to reproduce this document should be addressed to  
The Executive Director  
Uganda National Bureau of Standards  
P.O. Box 6329  
Kampala  
Uganda  
Tel: +256 41 4 333 2 50/1/2/3  
Fax: +256 41 4 286 123  
E-mail: info@unbs.go.ug  
Web: www.unbs.go.ug  DUS 1866:2018  
© UNBS 2018  – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ............................  iv 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative Reference ................................ ................................ ................................ .............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  2 
4 Requirements  ................................ ................................ ................................ ................................ .........  3 
4.1 General requirements  ................................ ................................ ................................ ...........................  3 
4.2 Types of edible natural c asings  ................................ ................................ ................................ ...........  3 
4.3 Grading  ................................ ................................ ................................ ................................ ...................  3 
4.3 Casing length from different animals  ................................ ................................ ................................ .. 5 
4.4 Casing defects  ................................ ................................ ................................ ................................ ....... 5 
5 Contaminants  ................................ ................................ ................................ ................................ .........  5 
5.1 Veterin ary Drug Residues  ................................ ................................ ................................ ....................  5 
5.2 Pesticide residues  ................................ ................................ ................................ ................................ . 6 
6 Hygiene  ................................ ................................ ................................ ................................ ...................  6 
6.1 Microbiology  ................................ ................................ ................................ ................................ ..........  6 
7 Food Additives  ................................ ................................ ................................ ................................ ....... 6 
8 Packaging  ................................ ................................ ................................ ................................ ...............  6 
9 Labelling  ................................ ................................ ................................ ................................ .................  7 
10 Nutrition and health claim  ................................ ................................ ................................ ....................  7 
11 Storage and transportation  ................................ ................................ ................................ ..................  7 
12 Sampling  ................................ ................................ ................................ ................................ ................  8 
Annex  A (informative)  Preparation and recovery of edible natural casings  ................................ ...............  9 
A.1 Preparation  ................................ ................................ ................................ ................................ .............  9 
A.2 Recovery  ................................ ................................ ................................ ................................ ................  9 
Bibliography  ................................ ................................ ................................ ................................ ......................  10 
 
 DUS 1866 : 2018  
iv © UNBS 2018  – All rights reserved  
 Foreword  
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Trade , Industry and 
Cooperatives established under Cap 327 , of the Laws of Uganda , as amended .  UNBS is mandated to co -
ordinate the elaboration of standards and is  
(a) a member of International Organisation for Standardisation (ISO) and  
(b) a contact point for the WHO/FAO Codex Alimentarius Commission on Food Standards, and  
(c) the National Enquiry Point on TBT  Agreement  of the World Trade Orga nisation (WTO).  
The work of preparing Uganda Standards is carried out through Technical Committees. A Technical 
Committee is established to deliberate on standards in a given field or area and consists of key stakeholders 
including government, academia, co nsumer groups, private sector and other interested parties.  
Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the 
general public for comments. The committee reviews the comments before recommending the dra ft standards 
for approval and declaration as Uganda Standards by the National Standards Council.  
The committee responsible for this document is Technical Committee UNBS/TC 2, [Food and Agriculture], 
Subcommittee SC 12, [Meat, poultry and processed products ]. 
This the first  edition  (US 1866 :2018 ), which has been tec hnically developed .  
 DUS 1866:2018  
© UNBS 2018  – All rights reserved  v 
 Introduction  
Natural casings are made from the sub -mucosa, a layer of the intestine that consists mainly of naturally  
occurring collagen . Collagen n atural casings are derive d from the intestinal tract of farmed animals, are edible 
and bear a close resemblance to the original intestine after processing. The outer fat and the inner mucosa 
lining are removed during processing.  
Natural casings breathe, allowing smoking and cookin g flavours  to permeate the casing and infuse the meat, 
giving the sausage a  rich, even flavour  throughout. Collagen n atural casings have unique natural curves and 
sheen, with rounded ends where the sausage is linked giving the sausage visual appeal . They a lso determine 
the final size and shape of the sausage product. Collagen natural casing  serve as processing molds, 
containers during handling and shipping, and as merchandising units for display . 
Natural  casings are traditional products that have been used in the production of meat specialties for centuries 
and have remained virtually unchanged in function, appearance, and composition. Salt and water are all that 
used for cleaning and preservation. Collagen n atural casings are the only casings that can be us ed in organic 
sausage production .  
Natural  casing are delivered  exclusively from the gastro -intestinal tracts of  swine, cattle, sheep and goats . 
 DRAFT UGANDA STANDARD  DUS 1866: 201 8 
 
© UNBS 2018  – All rights reserved  1 
 Edible n atural casing s — Sausages  — Specification  
1 Scope   
This Draft Uganda Standard specifies the  recommendations, requirements, test and sampling method s for 
Edible natural casings  used in sausage production fit for the food industries and human consumption.  
2 Normative Reference  
The following referenced documents referred to in the text in such a wa y that some or all of their content 
constitutes requirements of this document. For dated references, only the edition cited applies. For undated 
references, the latest edition of the referenced document (including any amendments) applies.  
US 779 , Requireme nts for the transportation of meat and meat products  
US 737 , Hygienic requirements for the production of packaged meat products (processed or manufactured  
US CAC/GL 50 , General guidelines on sampling  
US CAC/RCP 58 , Code of hygiene practice for meat  
US EAS 38, Labelling of prepackaged foods — Specification  
US 45 , General standards for food additives  
US 1659 , Materials in Contact with Food — Requirements for Packaging materials  
US ISO 6579,  Microbiology of food and animal feeds — Horizontal method for detecti on, enumeration and 
serotyping of Salmonella, Enumeration by a miniaturized most probable number technique  
US ISO 6888 -1, Microbiology of food and animal feeds — Horizontal method for enumeration of Coagulase - 
positive staphylococci. (Staphylococcus aureus  and other species), Detection and MPN technique for low 
numbers  
US ISO 7251 , Microbiology of food and animal feeds — Horizontal method for detection, enumeration of 
presumptive Escherichia coli – Most probable number technique  
US ISO 21527 -1, Microbiology  of food and animal feeding stuffs — Horizontal method for the enumeration of 
yeasts and moulds — Part 1, Colony count technique in products with water activity greater than 0.95  
US ISO 21527 -2, Microbiology of food and animal feeding stuffs — Horizontal m ethod for the enumeration of 
yeasts and moulds — Part 2: Colony count technique in products with      water activity less than or equal to 
0.95 
US ISO 4832 , Microbiology of food and animal feeding stuffs — Horizontal method for the enumeration of 
coliforms  — Colony -count technique  
US ISO 4833 -1, Microbiology of the food chain – Horizontal method for the enumeration of microorganisms – 
Part 1: Colony count at 30 °C by the pour plate technique   
2 © UNBS 2018  – All rights reserved  
 US ISO 4833 -2, Microbiology of the food chain – Horizontal method for the enumeration of microorganisms – 
Part 2: Colony count at 30 °C by the surface plating technique  
US EAS 12, Potable water — Specification  
US EAS 35 , Fortified food grade salt — Specification  
3 Terms and definitions   
For the purposes of this document,  the following terms and definitions apply.  
3.1  
round  
animal casings derived from the small intestines of cattle, , sheep, goats and pigs   
3.2 
middles  
animal casings derived from large intestines of cattle and pigs   
3.3 
middle Cap or Cap  
animal casing p repared from the caecum of blind gut of the pig 
3.4 
bungs  
animal casing prepared  from the caecum (beef bung and pig bung)  
3.5 
bladders  
animal casings prepared from the urinary bladders of pigs and cattle  
3.6 
weasands  
animal casing prepared made from the mu cosa of oesophagus of cattle  
3.7 
runners  
animal casings prepared from small intesti nes of c attle 
3.8 
nodule  
small rounded structure  
3.9  
cicatrice   
scar of healed -up wound.  
3.10 
Domestic  
small grease spot in the casing.  
3.11.  
Kink  
twisted loop in the casin g 
3.12 
Rust  
black spot caused by putrefaction due to bacterial or fungal action  DUS 1866: 2018  
© UNBS 2018  – All rights reserved  3 
 3.13 
Casing  
material that encloses the filling of a  sausage  
3.14 
Hank  
is a unit of measure used in sausage casing  
4 Requirements  
4.1 Gene ral requirements  
Edible  natur al casings shall;  
a) be obtained from healthy animals slaughtered in licensed premises and subjected to ante -mortem and 
post-mortem inspection according to the procedure prescribed in US CAC/RCP 58  
b) be clean, safe and suitable for the intended purpose, prepare d and handled in a sanitary manner and 
where no contamination or exposure to infectious material during handling  
c) be prepared under hygienic conditions and shall be wholesome not have been subjected to any 
bacterial activation or fermentation  
d) quality of wat er used for processing shall be of potable quality and in accordance with US EAS 12.  
e) be strong enough to resist the pressure produced by filling them with sausage mix  
f) be permeable to water vapour and gases , thus allowing fillings to dry  
g) absorb smoke for ad ditional flavour and preservation  
h) expand or shrink firmly  attached to the sausage mix  
i) be closed at the ends by tying or clipping  
j) free from foreign matter and odour  
k) be free from any parasitic infestation and from scars of healed -up woun ds 
4.2 Types of edibl e natural casings  
Edible  natural casings shall be from;  
a) Dried cattle casings known commercially as ‘Beef Casings’  
b) Salted cattle casings known commercially as ‘Beef Casings’  
c) Salted sheep or goat casings known commercially as ‘Sheep or goat Casings’  
d) Salted pig casings known commercially  as ‘ pig Casing ’. 
4.3 Grading  
Edible natural casing shall be graded basing on quality as in Table 1.   
4 © UNBS 2018  – All rights reserved  
 Table 1 — Quality grading of Edible natural casing  
S/N Grade  Requirement  
Dried Cattle 
Casings  
 
 Prime quality  (PQ)   The casings shall be of uniform natural colour, lustrous throughout without 
any spot or mark and free from discolouration. The casing wall shall be 
intact, free from any tear or laceration and shall be perfectly rolled. The 
casings shall also be free fro m salt burns, rust, domestics, black nodes, 
slime, mucus, dung, mould or fungus infestation and free from defects like 
holes, blisters, lacerations, nodules and cicatrices . 
Grade 1  The requirements for this grade shall be the same as for Grade PQ except 
that a slight deviation in colour and folds and a few black nodes shall be 
permitted. Total fat streaks shall not exceed 40 per meter; a streak of fat 
shall not exceed 30 mm in length and 10 mm in breadth. The middle of the 
seam shall be free from fat -streaks. 
Grade 2  Casings not c onforming to Grade PQ or Grade 1  due to defect in rolling 
and/or having larger black nodes or rough texture or streaks of fat not 
exceeding 60 in a meter shall be classed in this grade . 
Grade 3  This grade shall include short pieces of any or all of the above grades and/or 
having fat streaks in excess of 60 in a meter . 
Bladder  Bladder, otherwise conforming to requirements of Grade PQ.  
Weasands  Weasands, otherwise conforming to requirements of Grade PQ.  
Bungs,  Bungs, other wise conforming to requirements of Grade PQ.  
Fat ends  Fat ends, otherwise conforming to requirements of Grade PQ.  
Salted Cattle 
Casings  Prime quality  The casings shall be of uniform natural colour, lustrous throughout without 
any spot or mark and free from discolouration. The casing wall shall be 
intact, free from any tear or laceration and shall be perfectly rolled. The 
casings shall also be free from salt burns, rust, domestics, black nodes, 
slime, mucus, dung, mould or fungus infestation and free fro m defects like 
holes, blisters, lacerations, nodules and cicatrices. On being inflated with air, 
rolled round the finger and pressed, the casings shall burst with a sharp 
sound.  
Bladder  The wall shall be of uniform natural colour, lustrous throughout wit hout any 
spot or mark and free from discolouration. The material shall be free from 
any tear or laceration. The material shall also be free from salt burns, rust, 
domestics, black nodes, slime, mucus, dung, mould or fungus infestation 
and free from defects  like holes, blisters, nodules and cicatrices . 
Weasands  Weasands, otherwise conforming to requirements of ‘Bladder’  
Bungs,  Bungs, otherwise conforming to requirements of ‘Bladder’  
Fat ends  Fat ends, otherwise conforming to requirements of ‘Bladder’.  
Salted Sheep 
Casings (including 
Goat Casings)  Prime Quality (PQ) 
or Grade  1 The casings shall be of natural colour throughout without any discolouration. 
The casing wall shall be intact and not torn or lacerated. The casings shall 
also be free from salt b urns, rust, domestics, black nodes, slime, mucus, 
dung, mould or fungus infestation and free from defects like holes, blisters, 
lacerations, nodules and cicatrices. The casing shall not burst when filled 
with air or water to its normal capacity and slightl y pressed. The rings or 
hanks shall have been cured properly with common salt . 
Grade 2  The requirements for this grade shall be the same as for Grade PQ except 
that a slight deviation shall be allowed in respect of colour and/or strength 
and pinholes on walls not exceeding 2 in a meter. The material should be fit 
for use in preparation of sausages.  
Grade 3  The requirements for this grade shall be the same as for Grade II  except 
that the presence of nodules shall be permitted  
Salted pig Casings  Prime Q uality (PQ)  The casings shall be of natural colour throughout without any discolouration. 
The casing wall shall be intact and not torn or lacerated. The casings shall 
also be free from salt burns, rust, domestics, black nodes, slime, mucus, DUS 1866: 2018  
© UNBS 2018  – All rights reserved  5 
 dung, mould or fungus infestation and free from defects like holes, blisters, 
lacerations, nodules and cicatrices. The casing shall not burst when filled 
with air or water to its normal capacity and slightly pressed. The rings or 
hanks shall have been cured properly with  common salt .  
 
4.3 Casing length from different animals  
Edible natural casings shall  be measured in hanks as Table 2 ; 
Table 2—Edible collagen natural c asing Length of different animals  
Species  Type  Length (m)  
Cattle / pig Runner  25-40 
Middle  5.5-7.5 
Bung  1-1.5 
Weasand  5.5 
Bladder  20-35cm wide  
Sheep  Round  27 
Goat  Round  22 
 
Note 1  
• 1 hank = salted sheep and goat casings of 92 metres in length  
• 1 hank = dried cattle casings of 180 meters in case of runners or 90 meters in case of middles  
4.4 Casing defects  
Edible  natural casings shall be free of the following defects;  
a) Dull colour: (grayish or greenish instead of white or milky) due to defective cleaning.  
b) Nodules: due to oesophagostomum (a round worm) in the intestines of sheep, goat and pigs  
c) Holes and lacerations: caused by negligence or rough handling of guts during processing.  
d) Salt burns: due to long storage of guts in the salt or packed loosely leaving the air inside. Such 
patches may also develop due to defective salt, which has calcium and magnesium ions.  
e) Defective grading  like c icatrices, d omestics , kink and rust  
5 Contaminants  
5.1 Veterinary Drug Residues  
Edible  natural casings shall have a maximum residual limit for veterinary drugs in accordance with Codex 
standards    
6 © UNBS 2018  – All rights reserved  
 5.2 Pesticide residues  
Edible natural casings shall have a maximum residual limit for veterinary drugs in accordance with Codex 
standards.  
6 Hygiene  
Edible n atural casings  shall be handled, stored and transported following hygienic practices in accordance 
with US CAC/R CP 58, the person nel handling natural casings  shall also be clean and health y. 
6.1 Microbiology  
Edible  natural casings shall be free from mic roorganisms as stated in Table 3  below;  
Table 3  — Microbiological requirements for Edible  natural casings  
S/No.  Microorganism  Limit  Test method  
i) Salmonella spp  Absent  US ISO 6579  
ii) Total plate count, cfu per gram, Max.  106 US ISO 4833  
iii) Coliform count, cfu per gram, Max.  Absent  US ISO 4832  
vi) Yeast and mould count, cfu per gram, Max.  10 US ISO 21527 -2 
v) E.coli cfu per gram, Max  Absent  US ISO 7251  
vi) Staphylococcus areaus  Absent  US ISO 6888 -1 
 
7 Food Additives  
Edible  natural casings  shall be preserved prior to storage as in accordance with US 45 . 
8 Packaging  
Edible casings  shall be packaged  in food grade  material and in accordance with US 1659 . 
Edible natural c asings may be packaged using the following methods  in order to preserve the quality, extend  
shelf life and add the aroma  using . Any other method may also be used,  
a) Dry salt packed: Excess moisture is  removed from the casings and packed in a semi -dry state. This 
type of packaging is usually appropriate for long distance travel and/or prolonged storage at ambient 
temperatures.  
b) Slush or pre -flushed packed: Casings are packaged in a water/salt mixture. Th e casings are very soft 
and flexible and do not require flushing prior to stuffing sausage.  
c) Pre-tube packed: Each strand of natural casing is shirred on a tube to allow one -step loading   of   the   
casings  directly onto the stuffing horn . 
 DUS 1866: 2018  
© UNBS 2018  – All rights reserved  7 
 9 Labelling  
In addition to the requirements of US EAS 38, the following labelling requirements shall apply and shall be 
legibly and indelibly marked.  
a) Common name of the product to be declared on the label as ‘’ Edible  natural casing'’  
b) Type of Edible collagen n atural casin g eg ‘ cattle, goat , sheep and pig  
c) The grade and the length  
d) Net contents by weight (‘ System International') units;  
e) Name and physical address of the manufacturer/distributor;  
f) Country of origin;  
g) Lot /batch identification;  
h) Shelf life: best before/use by date ; 
i) Statement ‘Food for Human Consumption’ shall appear on the package;  
j) Storage conditions as “Store in a cool dry place away from contaminants”:  
k) Instructions on disposal of used package;  
l) Each container may also be marked with a Certification Mark  
m) Any other requirement as given OIML R87, Quantity of product in pre -packages.  
n) Religious note eg Halal or not Halal  
o) Names of the ingredients used  
p) Pack aging date.  
q) Instruction for use  
r) Product storage life of properly stored natural casings can last under refrigeratio n for at least one to 
two years . 
10 Nutrition and health claim  
Edible n atural casing may have health claims associated with nutritional composition and health. Such claims 
when declared shall be consistent with US EAS 805 . 
11 Storage and transportation  
11.1 Edibl e natural casing shall be stored  and transported as in accordance with US 737 and US 779.  
11.2 Salt used in salted natural casings shall be in accordance with US EAS 35  
Note 2  
Natural casings shall be Stored in  air tight container s and refrigerate   
8 © UNBS 2018  – All rights reserved  
 Natural casings shall not be frozen since f reezing a natural casing will weaken it and it will be no good after it has thawed.  
12 Sampling  
Sampling shall be carried out in accordance with US CAC/GL 50 . DUS 1866: 2018  
© UNBS 2018  – All rights reserved  9 
 Annex  A 
(informative)  
 
Preparation  and recovery of e dible  natural casings  
A.1 Preparation  
• Casings should be manufactured from gut of healthy animals, which have been properly slaughtered, 
inspected and passed.  
• Intestines for processing should not have ulcers and heavy parasitic infestations with nodule s.  
• Sanitary handling conditions should be maintained from slaughter to final packing.  
• The product should be clean with good colour and without objectionable odour. It should have proper 
length and be sufficiently cured.  
• The preparation of casings derived from different species of animals is basically similar.  
• The main difference is pig; sheep and goat casings being very fragile require more careful treatment than 
that of beef’s casings.  
• Because of this removal of fat from the casings of the s mall animals must be performed by hand, helped 
with a scrapping sticks while patting of beef casings require harsh treatment.  
• beef casing has to be turned inside out, whereas sheep and goat casings are sold unturned.  
• Pig casings, if possible, should be turned after defattening  
A.2 Recovery  
• The removal of entrails should be done in such a way that the whole intestinal tract comes out without 
being damaged by cuts or unnecessary contamination.  
• The separation and division in to different parts shoul d take place on a table with a supply of running 
water.  
• The casing should be detached and the ligature made so that the contents do not run out.  
• As soon as the different parts are separated they undergo further treatment.  
• When the quantity is larg e, it is essential to have different casings treated separately.  
• For example, the bladder and weasand that are to be dried should not be mixed with those, which are 
to be salted.  
• Sheep and goat casings are generally stored wet and salted whereas catt le casings are generally 
dried in processing and sprinkled with insecticide to safeguard during storage period.  
  
10 © UNBS 2018  – All rights reserved  
 Bibliography  
[1] Indian Standard - animal casing -grades and specification (1981) Second revision   
[2] Jay B. Wenther – Basics of casing, Interna tional Natural sausage casing Association, Washington DC 
20005  
[3] Joseph Sebranek (PH.D), Natural Vs artificial casings, (2010), evaluating which is best for your 
products 
. DUS 1866: 2018  
© UNBS 2018  – All rights reserved  11 
 Certification marking  
Products that conform to Uganda standards may be marked wi th Uganda National Bureau of Standards 
(UNBS) Certification Mark shown in the figure below.  
The use of the UNBS Certification Mark is governed by the Standards Act, and the Regulations made 
thereunder. This mark can be used only by those licensed under th e certification mark scheme operated by 
the Uganda National Bureau of Standards and in conjunction with the relevant Uganda Standard. The 
presence of this mark on a product or in relation to a product is an assurance that the goods comply with the 
requirem ents of that standard under a system of supervision, control and testing in accordance with the 
certification mark scheme of the Uganda National Bureau of Standards. UNBS marked products are 
continually checked by UNBS for conformity to that standard.  
Further particulars of the terms and conditions of licensing may be obtained from the Director, Uganda 
National Bureau of Standards.  
 
 DUS 1866: 2018    
 
ICS 67.120.10  
Price based on nn pages  
© UNBS  2018 – All rights reserved