Old Tom

1. Borehole

Water used for brewing is drawn from one of two brewery boreholes up to 180 metres (600 feet) deep. This water is well suited for brewing but we make some adjustments to it for different beers, including reducing some of the hardness. After this has been done we refer to it as Brewing Liquor which is usually shortened to ‘Liquor’. Some borehole water is used directly for cooling (attemperating) the fermentations.

4. Malt

Malt is made mainly from barley but also from several other cereals, especially wheat. The malting process mimics the natural germination of the grain in the field. Barley is steeped in water and then spread on floors until the shoot and rootlets start to emerge. It is then dried (kilned). The grain looks somewhat unchanged at the end of this process but a lot of the starch has been converted to sugar and the grains are more friable (crumbly). The extent of the kilning determines the colour of the malt and hence the beer, as well as influencing flavour.

Robinsons purchase their malt from British Maltsters who obtain their barley from British Farms, largely located in the Eastern Counties of England and Scotland.

5. Sugar

To some brews sugar is added. This may be done for flavour reasons or to increase the fermentability of the wort.

6. Cereals

We have the option of using unmalted “raw” cereals although currently these would only be used by a contract brewing customer who particularly requested it.

7. Cereal Cooker

This vessel can be used for two completely separate duties. Unmalted cereals can be cooked before pumping the resultant cereal mash into the mash vessel for mixing with the malt mash. Alternatively, the vessel can be used for dissolving sugars before pumping the resultant syrup into the copper.

8. The Mash Vessel

The mash vessel has dimpled heating panels in the walls and a patented system for vibrating the mash to increase the extract yield from malt and reduce oxygen levels. Very important changes take place in this vessel. Almost all the remaining malt starch is converted to sugar as a result of the naturally occurring enzymes, present in the grain. Also proteins, which would otherwise cause hazes and other problems, get broken down. Precise temperature control is very important.

9. Lauter Tun

The lauter tun is a vessel to separate the liquid sugary wort from the solid remains of the grain so it acts like a filter. There is a slotted base through which the wort flows. Brewing liquor is sprayed onto the top (sparging) to rinse out all the extract.

10. Spent Gain Tank

This tank stores the spent grains until a whole wagon load has accumulated. Spent grain is a valuable and economical source of food for cattle and in winter, demand can exceed supply in some areas of Great Britain.

11. Hops

Hops in UK are mainly grown in Kent, Worcestershire and Herefordshire. In the copper we use mainly hops from these areas. Hops provide bitterness and other flavours and assist in extending the keeping qualities of cask conditional beer.

12. Hops

Hops used in the Hopnik provide particular flavours and aromas which come from varieties grown all over the world including the UK. Each variety has its own individual flavour profile. Sometimes a blend is used, sometimes just one variety, in order to produce a beer of the desired character. This is one of many reasons why different beers from the same brewery taste so different.

13. Hop Nik

This is a recently designed vessel and Robinsons are the proud owners of the largest hopnik in the world! It is a very specially designed huge strainer which allows us to extract many of the great flavours from “leaf” hops that in conventional breweries get boiled away rather than finishing up in the beer. This is especially important in ales. The plant is designed so we can use it or not as we please, so existing beers can be brewed to existing recipes whilst new beers can be brewed using particular hop varieties to impart distinctive and exciting flavours and aromas.

14. Spent Hops

These can be used to dig into the soil and are popular with allotment holders and gardeners. They are great for improving the tilth of the soil and retaining moisture in the summer. They only rot down slowly so the benefit is long lasting.

15. Whirlpool

This is a circular vessel, the wort entering tangentially; thus the wort rotates. During boiling, proteins coagulate and these and the remains of the hops move to the centre of the vessel as a result of centripetal force. The bright wort is drawn off, leaving the solids, known as ‘trub’. As this is protein rich, the trub is saved in a small tank and ultimately mixed with the spent grain.

16. Wort Cooler

This is a counter current plate heat exchanger. Hot wort passes through alternate spaces between stainless steel plates, in one direction. In the intervening spaces, cold liquor is pumped in the reverse direction. Thus the hot wort emerges cold and the once cold water emerges hot. This is recovered for use in the next brew. This saves energy and water and reduces waste water.

17. Fermenting Vessels

Yeast is now added to the cooled wort. The vessel is only about three quarters filled as during the next five days or so, the yeast multiples rapidly forming a large head. When complete, almost all the sugar in the wort will have been converted to alcohol and at last we can now call the product ‘beer’. However it is still very cloudy due to the yeast.

18. Packaging

In cask beer, the addition of finings will cause the yeast to settle out. For all other forms of packaging, the beer will be chilled, matured and filtered before kegging or bottling. Old Tom is supplied to some pubs in cask, but is also available in distinctive bottles in both pubs and supermarkets.