Reference number  
DRS 125: 2018 
© RSB 2018 
 
 
 RWANDA 
STANDARD  DRS 
125 
 
Second  edition  
2018-mm-dd 
 
Fresh tofu — Specification  
 
  DRS 125:201 8 
©RSB 2017  - All rights reserved                  ii 
 In order to match with technological development and to keep continuous progress in industries, 
standards are subject to periodic review. Users shall ascertain that they are in possession of the latest 
edition  
 
 
 
 
 
 
 
 
© RSB 2018 
All 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 
prior written permission from R SB. 
Requests for permission to reprodu ce this document should be addressed to : 
Rwanda Standards  Board  
P.O Box 7099 Kigali -Rwanda  
KK 15 Rd, 49  
Tel. +250 252 586103/ 582945  
Toll Free: 3250  
E-mail: info@rsb.gov.rw  
Website: www.rsb.gov.rw   DRS 125:201 8 
iii                ©RSB 2018 - All rights reserved  
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ...................  iv 
1 Scope  ................................ ................................ ................................ ................................ .............  1 
2 Normative references  ................................ ................................ ................................ ...................  1 
3 Terms and definitions  ................................ ................................ ................................ ..................  2 
4 Esse ntial composition, quality and nutritional requirements ................................ ..................  2 
4.1 Raw materials  ................................ ................................ ................................ ...............................  2 
4.2 Optional ingredients  ................................ ................................ ................................ .....................  3 
4.3 Compositional requirements  ................................ ................................ ................................ ....... 3 
4.4 Nutritional and organoleptic factors  ................................ ................................ ..........................  3 
5 Heavy metals  ................................ ................................ ................................ ................................ . 3 
6 Hygiene  ................................ ................................ ................................ ................................ ..........  4 
7 Microbiological re quirements  ................................ ................................ ................................ ..... 4 
8 Packaging  ................................ ................................ ................................ ................................ ...... 4 
9 Labelling  ................................ ................................ ................................ ................................ ........  4 
10 Sampling  ................................ ................................ ................................ ................................ ....... 2 
 DRS 125:201 8 
©RSB 2017  - All rights reserved                  iv 
 Foreword  
Rwanda Standard s are prepared  by Technical Committees and approved by R wanda Standards Board (RSB) 
Board  of Directors in  accordance with the procedures of RSB, in compliance with Annex 3 of the WTO/TBT 
agreement on the preparation, adoption and application of standards.  
The main task of technical committees is to prepare national standards.  Final Draft Rwanda S tandards adopted 
by Technical committ ees are ratifie d by me mbers of RSB Board of Director s for publication and gazettment as 
Rwanda Standards.  
DRS 125 was prepared by Technical Committee RSB/TC 003, Cereals, Pulses, Legumes derived Products  
In the preparation of this standard, reference was made to the foll owing standard:  
1) CODEX STAN 175 -1989, Codex general standard for soy protein products.  
The assistance de rived from the above source is hereby acknowledged with thanks.  
This second  edition cancels and replaces the first edition (RS  125:2012 ), which has been technically revised.  
Committee membership  
The following organizations were represented on the Technical Committee on Cereals, Pulses, Legumes 
derived Products  (RSB/TC 003) in the preparation  of this standard.  
ADMA International Ltd  
FARMFRESH Ltd  
Lamane B akery  
Rwanda Agriculture Board  
SIMBA Supermarket  
SOSOMA Industries  
Rwanda  Standards Board  (RSB) – Secretariat  
  DRS 125: 2018 
1                ©RSB 2018 - All rights reserved  
 Fresh tofu  — Specification  
1 Scope   
This standard specifies requirements, sampling and test method s for fresh tofu intended for use in food 
preparations  for human  consumption  
2 Normative references   
The following documents are referred to in the text in such a way 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 reference d document (including any amendments) applies.  
AOAC 963.21, Arsenic in food Kjeldahl flask digestion  
AOAC 999.10, Lead, Cadmium, Copper, Iron, and Zinc in foods, Atomic Absorption Spectrophotometry after  
microwave digestion  
EAS 147 -1:2000, Vinegar — Specification — Part 1: Vinegar from natural sources  
ISO 16649 -2, Microbiology of food and animal feeding stuffs -- Horizontal method for the enumeration of beta -
glucuronidase -positive Escherichia coli -- Part 2: Colony -count technique at 44 degrees C usin g 5-bromo -4-
chloro -3-indolyl beta -D-glucuronide  
ISO 2171, Cereals, pulses and by -products — Determination of ash yield by incineration  
ISO 6541 , Agricultural food products — Determination of crude fibre content — Modified Scharrer method  
RS EAS 38, General  Standard for the Labelling of Pre -packaged Foods . 
RS EAS 762, Dry soybeans — Specification  
RS ISO 11085, Cereals, cereals -based products and animal feeding stuffs — Determination of crude fat and 
total fat content by the Randall extraction method  
RS ISO 2 0483, Cereals and pulses — Determination of the nitrogen content and calculation of the crude protein 
content — Kjeldahl method  
RS ISO 21527 -2, Microbiology of food and animal feeding stuffs -- Horizontal method for the enumeration of 
yeasts and moulds -- Part 2: Colony count technique in products with water activity less than or equal to 0,95  
RS ISO 24333 , Cereals and cereal products — Sampling   
©RSB 2017  - All rights reserved                  2 
 RS ISO 6579 -1, Microbiology of the food chain -- Horizontal method for the detection, enumeration and 
serotyping of Salmonella -- Part 1: Detection of Salmonella spp  
RS ISO 6888 -1; Microbiology of food and animal feeding stuffs — Horizontal method for the enumeration of 
coagulase -positive staphylococci (Staphylococcus aureus and other species) — Part 1: Technique usi ng Baird -
Parker agar medium  
3 Terms and definitions  
For the purposes of this standard, the follow ing terms and definitions apply . 
3.1 
fresh Tofu  
food made by coagulating soya milk and then pressing the resulting curds into soft white blocks  
3.2  
soya milk or  soy drink/beverage  
 
beverage made from soya beans. It is a stable emulsion of oil, water, and protein, produced by soaking dry  
soybeans and grinding them with water.  
3.3 
soybean  
grain that consists of 50 percent or more of whole or broken soybeans (Glycine max (L.) Merr.) that does not  
pass through an 8/64 round -hole sieve and not more than 10.0 percent of other grains for which standards  have 
been established.  
4 Essential composition, quality  and nutritional requirements  
4.1 Raw materials  
The following raw materials shall be used in the manufacture of fresh tofu:  
a)  Soybean complying with RS EAS 762 ; 
b) Vinegar complying with RS EAS 147 -1; and  
c)  Potable water complying with RS  EAS 1 2 DRS 125: 2018 
3                ©RSB 2018 - All rights reserved  
 4.2 Optional ingredients  
Optional ingredients which may be used shall comply wit h relevant standards. They include but are not limited 
to the following:  
a) Vitamins and minerals ; 
b) Salt complying with RS EAS 35; and  
c) Herbs and spices.  
4.3 Compositional requirements  
The compositional requirements for Fresh Tofu shall be as given in Table 1.  
Table 1 – Composition requirements for fresh tofu  
S/N  Parameter  Maximum limits  Test method  
i.  Crude protein, % m/m, on dry matter 
basis  60- 90 RS ISO 20483  
ii.  Crude fiber ( % on a dry weight basis)  0.5-6  ISO 6541  
iii.  Ash (on a dry weight basis)  Not less than 10% ISO 2171  
iv.  Fat content % 2 -5 RS ISO 11085  
4.4 Nutritional and organoleptic factors  
4.4.1  Processing should be carefully controlled and sufficiently thorough to secure optimum flavour and 
palatability, as well as to control such factors as trypsin inhibitor and hemaglutinins, in accordance with intended 
use.  
4.4.2  The finished product shall be  of characteristic flavour, free from taint and rancidity.  
5 Heavy metals  
Fresh Tofu shall conform to the limits for heavy metal contaminants specified in Table 2.  
Table 2 ― Heavy metal limits in fresh tofu  
S/N  Heavy metal  Maximum level  (mg/kg)  Test method  
i.  Lead (Pb)  0.3 AOAC 999.10  
 ii.  Copper (Cu)  5.0  
iii.  Zinc  5.0  
iv.  Arsenic (As)  0.2  AOAC 963.21   
©RSB 2017  - All rights reserved                  4 
 6 Hygiene  
Fresh Tofu shall be prepared in premises built and maintained under the hygienic conditions stipulated in the  
RS CAC/RCP 1.  
7 Microbiological requirements  
Fresh tofu shall comply with the maximum microbiological limits stipulated in table 3  
Table 3 — Microbiological limits  
S/N  Microorganism   Maximum limit  Test method  
i.  Total viable counts , CFU/g  105 RS ISO 4833 -1 
ii.  E.coli  CFU/g   Absent  ISO 16649 -2 
iii.  Staphylococcus aureus  CFU/g  Absent  RS ISO 6888 -1 
iv.  Salmonella Sp p CFU/  25g Absent  RS ISO 6579 -1 
8 Packaging  
Fresh Tofu shall be packed in suitable  food grade made of substances which are safe and suitable for their 
intended use and which will not  impart any toxic substance or undesirable odour or flavour to the product.  
9 Labelling  
In addition to the requirements of RS EAS 38, the following requirements shall apply and shall be legibly and 
indelibly marked:  
d) name of the product, ‘Fresh  Tofu’;  
e) name an d physical address of the manufacturer;  
f) net weight;  
g) list of ingredients in descending order of proportion;  
h) date of manufacture;  
i) expiry date;  
j) country of origin;  
k) instructions of use; and  
l) instructions of storage.   
©RSB 2017  - All rights reserved                  2 
 10 Sampling  
Sampling of fresh tofu shall be done  in accordance with RS ISO 24333.  
 DRS 125:201 8 
ICS 67.060  
 
 
©RSB 2018 - All right s reserved