Yeast slanted agar culture

The yeast is activated beforehand in the wort then it is transferred onto a wort as the culture medium, then it is inoculated. After a successful monitoring and controlling of the growth the pure cultivated strains are then prepared for dispatch.

The Slant agar culture tubes are packed to avoid damage and for longer destinations are packed in a cooled transport packaging.

This is the appropriate packaging with little volume and weight for longer distances. The only disadvantage is that the slanted agar culture has to be in the first step used for a small wort volume (100 ml).

Yeast on sterilized cotton wool

A similar method comparable to the slant agar culture, a dried yeast culture is placed on the sterilized cotton wool.

The advantage of this method compared to the slant agar culture is due to the longer life period in a non-cooled situation and the usage of a break proof tube for the transportation. The wort usage of (100 ml). The disadvantage of this method is that pure cultivated yeast cannot be sub-cultivated.

Liquid Culture

Liquid yeast is delivered in aluminium vessels (500 ml). This is the only method for transporting larger amounts of yeast. This saves the end user the first steps of cultivating in a laboratory and reduces the time consuming planning of the initial pure cultivation. Therefore the biological risk is less for the brewery.

Due to the fact that less human contact occurs with the pure cultures. The only disadvantage is the larger volume and the fact that the pure cultivated yeast strains categorically have to be cooled during dispatch and shipment.

Compressed dried yeast

Larger yeast amounts can be dispatched as compressed dried yeast that can be implemented directly for the pitching and for the cultivation within the brewery. It is to be pointed out that compressed yeast has to be used in sterile conditions when removed from its packaging in a sterile wort and has to be re-suspended.

The compressed dried yeast is stored in an aluminium container. It is not recommended (more than 6 days) as the yeast may loose its fermentation activity. This product is only available as strains W 34/70 and W 34/78.

Kryo-Pearls

The Kryo–Pearls of the Hefebank Weihenstephan are a Pure Yeast, that is on crystalized pearls "Shock-Frozen". The Pearls are produced so that the yeast cells as well as the surface and the hollow spaces within the pearls can be immobilized in a frozen form.

This character of shock – freezing guarantees the highest activity once the cultures have thawn and it has a viability rate of up to a period of one week after the thawing process.

Advantages

• Small packaging (ideal for shipping)
• No breakage during shipping
• Can be removed individually therefore a parallel start to a laboratory pure cultivation possibility is given.
• Better protection during the handling
• Exact dosage during the start of the pure cultivation in a laboratory (3 Pearls/100ml)
• Good possibility of the "worst-case" to ensure that the storage of a reserve cultivation
  is on hand for up to one year.