Quality Control of Down

A vital activity in each workshop is to accurately determine the quality of the down. Upon arrival of a new batch, a sample is immediately taken and examined. Then with each wash, and after every subsequent step of the production process, new samples are made and examined. Important quality control questions are asked such as: Is the down pure? What is the oxygen content? Is the down sufficiently elastic? etc. Only when all checks have been carried out and all results meet quality specifications, the down is released for further processing.

Quality control of down in the laboratory
A Kauffmann employee inspects the down after the last wash.

Quality Determination in 6 Steps

1) Determination of Species

The first thing to determine is whether we are dealing with duck down or goose down. With the aid of a magnifying glass, a trained eye can see the difference: the tiny barbs on the hair differ in size and position. With goose down, as opposed to duck down, the barbs are slightly larger, and located in the middle rather than at the end of the hairs.

2) Determination of the Proportion of Suitable Down

After the type of down is determined, the quality of the base material is analysed by comparing the percentage of down to by-product. Three grams are tested to assess the amount of usable down to broken down and feathers.

Inspect down and feathers in laboratory

3) Determination of the Fill Power

The most important aspect of the down quality is the fill power. This is measured in ''mm / 30g'' or in CUIN. The fill power indicates the down’s ability to return to its original form after being compressed. The better the down is at decompressing, the more air it can hold, and the better it is at insulating and keeping us warm.

Fill power in cuin table

4) Determination of Purity

The purity or transparency of the down is also assessed. After each washing, the used water is poured into a cylinder with a black cross on the bottom. If this cross is still recognizable after filling the cylinder with 30cm of liquid, then the down is well enough washed and it is officially considered 'pure'. When the down is qualified as 'impure', the wash is repeated.

Of course, every workshop has its own quality standards. Kauffmann, for example, only uses down with a cross recognizable at a height of 80 cm.

5) Determination of the Oxygen Content

After the down is qualified as 'clean' and 'transparent', the oxygen content is measured. 100 grams of test material is used to determine this. With the oxygen test, any harmful substances that cannot be detected with the naked eye are identified and removed.

Measuring cylinder with liquid

6) Determination of the Residual Fat Content

Last, but certainly not least, the residual fat content is measured. Down with too low residual fat content (less than 0.7%) is fragile and will not last long. Conversely, if the residual fat content is too high (more than 2%), the down will contain unpleasant odours.