PRE-SHIPMENT

INSPECTION

Pre-shipment inspection is OFCO Group's core service


Buyers confirm order directly to Vietnamese suppliers and request OFCO for inspection. When necessary, we follow with suppliers to ensure that there is no misunderstanding regarding the specification and quality between both parties. Our inspections are systematically carried out by two people at the same time (one Vietnamese and one foreigner). Our team emphasize on the sampling method to make sure to come up with a representative result. After inspection we send by mail to our customers a comprehensive and objective quality report supported by pictures. We also systematically provide extensive analysis to help them interpret the results and make an informed and wise decision about their consignments.

To our regular customers we also offer advice and we guide them on their seafood purchase in Vietnam. We invoice only the buyers and do not accept any payment and/or compensation for suppliers.

For the complete list of our service, fees and responsibilities limits, please contact us for more information.






NET WEIGHT
 
INSPECTION

The net weight inspection is part of our pre-shipment inspection


The seafood world is controlled by strict international standards and applying correctly those standards is the basic to carry out correctly an inspection but that is not enough: common sense is at least as much important as standards.  Because applying norms or standards without correct understanding and without common sense can't give reliable result. It even can go against development of the quality because standards could become an obsession at the detriment of the quality.  

The control of the net weight is no exception to the rule.
Therefore, to check correctly the net weight of a product in real condition of inspection some 'adjustments' to most of the international standards are necessary. The term 'adjustments' has been used by a high representative of those organization while explaining to me how to follow those norms and standards. 

As standard procedure to control the net weight, OFCO follows the codex alimentarius and AOAC International but with two necessary adjustments.

 

OFCO METHOD USED FOR BLOCK FROZEN AND
IQF PRODUCT
(STANDARD METHOD USED BY OFCO)

The samples are transferred into a water bath and kept immersed by hand. The product may be carefully agitated, till no more glaze can be felt by the finger-tips on the surface of the product: change from slippery to rough. Needed time, depending on size,shape and glaze content of the product, 10 to 60 sec. (and more in case of higher glaze contents or if frozen together). Remove adhering water by the use of paper towel (without pressure) and weight the product in a tared pan.

  

TWO ADJUSTMENTS NEEDED:
1- Several international methods impose to use a "gentle spray of cold water" to remove the glazing on IQF product. 

-> This method goes against the law of physics as the 'gentle spray of cold water' will instead increase the glazing if done in proper condition. Inspection must be carried in correct condition and therefore adjusting the 'strength' or the 'temperature' of this gentle spray of cold water is not a correct option. The best way is to go around this norm and dip the product into a water bath and kept it immersed by hand until no more glaze can be felt by the finger-tips on the surface of the product.

 2- Several international methods impose to use a "incline sieve at angle of 17-20° to facilitate drainage and drain exactly for 2 mn (or 3 mn according to the method)" instead of a towel or paper towel to remove the adhering water.

-> Theoretically this method is not consistent because if the control is done in proper condition a proportion of the adhering water will refreeze on the product. This proportion will depend on several external factors which are difficult to control as for example the temperature of the frozen product and of the room, the shape of the product and the irregularity of its surface.

Using a paper towel to remove the adhering water, as recommended by OFCO, is a more 'visible' external factors but with less impact on the result.   
-> Practically using an inclined sieve is simpler than OFCO Method on a small number of sample/product controlled. But as soon as the number of sample/product to be controlled increased, the risk of errors increases as well therefore affect the reliability of the result. 

Therefore, this method is theoretically not consistent and practically risky.

 

OFCO ALTERNATIVE  METHODS 

1- Using a "gentle spray of cold water to remove the glazing " is not an option as it is physically not possible. 

OFCO is an independent third party inspection:  We follow international norms and standards for our inspections but we do not have the obligation to lie about following or pretending to follow norms that are not applicable or not efficient.

We still remain open for any discussion and possible way to improve our inspection method and our services in general.

 2- Using a "incline sieve at angle of 17-20° to facilitate drainage" is possible and OFCO can follow this method if requested by our client with his/her understanding that the "gentle spray of cold water to remove the glazing" is anyway not an option.

Observation: In my opinion, the only reason to follow this method is just to follow blindly some international norms because the consistency of this method is less than 'using a paper towel' and the risk of errors are much bigger. Also considering that the previous step of those international norms which is 'using a gentle spray of cold water to remove the glazing' can't be followed, the international norms will be followed only partially and therefore not respected anyway. 

Remark: Codex alimentarius does not impose this method.


3-
Instead of measuring the net-weight on deglazed product, there is possibility to measure the net-weight on defrosted product. This method is not recommended but OFCO can apply it on Pangasius fillet. OFCO will follow this method only if requested by our client and with his/her understanding of the limit of the method.

Interest of the method: The added water on Pangasius fillet can go over 50% of the final weight (usually from 30 to 45%) and therefore it is an important part of the product we inspect. The classical control of the net weight (# deglazed method) do not consider how the muscle of the fillet retain the water. The 'defrosted method' will take in consideration the water release right away by the muscle after defrosting and according to the additive used, the variation can be significant. This method is more understandable for most of the final consumers and that is what they expect.

limit of the method: We do not recommend any more this method because the external factors are very difficult to control and the consistency of the method is much less than the deglazed method. Also, this method is far from international norm.

 

 

NET WEIGHT RESULT

INTERPRETATION

I didn't find in any publications a statistically correct interpretation of net weight result and its tolerance.


OFCO gives some guidance to buyers and to suppliers who are interested. This guidance does not have value of absolute and in anyway, the decision to accept or reject a consignment remains the decision of the buyers and the tolerances imposed by him/her. Buyers are invited to share those tolerances with the suppliers and with OFCO.

FOR OFCO NET WEIGHT TOLERANCE GUIDANCE, please contact vietnam@ofco.info 

 

 

 

 

OFCO Group, the seafood

specialist with common sense.

You need a seafood specialist -

not only a norms specialist.

 

 

For your reference:

CODEX ALIMENTARIUS COMMISSION
7.3.2 Determination of Net Weight of Products Covered by Glaze
As soon as the package is removed from low temperature storage, open immediately and place the contents under a gentle spray of cold water. Agitate carefully so that the product is not broken. Spray until all ice glaze that can be seen or felt is removed. Remove adhering water by the use of paper towel and weight the product in a tared pan.

CODEX ALIMENTARIUS COMMISSION
ANNEX B (Method for the determination of net content of frozen fish block covered by glaze)
The pre-weighed samples/sub-samples are transferred into the water bath and kept immersed by hand.  The product may be carefully agitated, till no more glaze can be felt by the finger-tips on the surface of the product: change from slippery to rough. Needed time, depending on size/shape and glaze content of the product, 10 to 60 sec. (and more in case of higher glaze contents or if frozen together). The deglazed sample/sub-sample, after removal of adhering water by use of a towel (without pressure) is immediately weighed. 

AOAC OFFICIAL METHOD 963.18
Net Contents of Frozen Seafoods Drained Weight Procedure
Remove package from low temperature storage, open immediately, and place contents under gentle spray of cold H2O. Agitate carefully so product is not broken. Spray until all ice glaze that can be seen or felt is removed. Transfer product to circular No. 8 sieve, 8 in. (20cm) diameter for 0.9 kg (2lb) and 12 in. (30cm) for >0.9kg (2lb). Without shifting product, incline sieve at angle of 17-20° to facilitate drainage and drain exactly 2 min (stop watch).