Friday, 8 July 2016

Bottled beer in the 1950’s – Bright Bottled Beers (part nineteen)

In an age when all beer bottles were returnable, washing them was of great importance. And washing them thoroughly.

Do breweries even have bottle washing machines today? Must look it up in Briggs.

“Before the up-to-date pressure washing machines were introduced, bottles were usually transferred from the soaker to brushes. In this type of plant the brushes revolve at high speed, and, passing through the neck of the bottle, clean the interior. Other brushes sometimes remove all outside dirt and labels at the same time. We are not fully convinced in our minds that the more modern system of cleansing by high water pressure, and discarding the brush, is fully justified. Properly made brushes well used get into the corners effectively. We even know that some of the very latest washers have reverted to the use of brushes. Their chief objection is that if by a mischance they are used on an oily or foul bottle which has escaped notice many others are contaminated before the trouble is discovered. Such contamination should, of course, never occur if the bottles have been properly nosed before being placed on the brush, as they definitely should be. Wear, and constant necessity for renewing the brushes, need not be excessive, although this argument is often advanced against them. The brush must, of course, be made of good bristle, and so arranged that the ends, which wear away first, can be replaced. The body of the brush will often outlast half dozen tips.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 350.

By “”properly nosed” I guess he means someone should sniff every bottle to check for contaminants. Sounds like a great job, sniffing bottles all day.

While you were reading that I checked in Briggs to see what happens with non-returnable bottles today. It seems that they just get rinsed:

“Non-returnable bottles are delivered new to the brewery. They are normally rinsed by spraying inside and outside several times. For rinsing the bottles are turned upside down and then returned to the upright position for filling. Rinsers are now almost integral with the filling machine. The process is designed to wet the bottles prior to filling and to ensure sterility by killing micro-organisms. Steam is usually jetted into the bottle for this purpose followed by a purge of sterile air. This results in 0.1 to 0.2 ml of condensate remaining in the bottle.”
"Brewing: science and practice", by Dennis E. Briggs, Chris A. Boulton, Peter A. Brookes and Roger Stevens, 2004, page 766.

This is a description of the more modern, brushless machines of the 1950’s:

“High-pressure washers are undoubtedly more economical when it comes to a question of labour and speed. These reasons are apparently why bottlers have adopted them on a large scale. Many types of these machines are offered for sale, each claiming its own particular advantages. With experience gained from the pioneer machines the various makers can now supply really commendable plant. Some submerge the bottles in caustic solution for a time as a preliminary treatment while others subject the bottles all the time they are in the machine to a heavy spray of the solution, both internally and externally. Provided that the bottles are turned over and emptied at least once during the process of washing, we consider that a combination of the two processes gives very fine results. It is important that adequate provision is made for a thorough final rinsing of the bottles, so that all traces of the caustic solution are removed. Unless this is done the bottles will not be bright, and the contents might be condemned on account of supposed haze.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, page 350.

I’d be worried about more than a possible haziness if there was caustic soda left in the bottle. Not something you’d want to drink, even in small quantities.

It’s odd that label removal isn’t mentioned. For Briggs it’s one of the trickiest parts of the washing process:

“Label disposal. The major challenge of the operation is the removal of the soggy mass of denatured label paper and foil. A label press is used to dewater the label pulp by about 80% and the caustic solution residue is returned to the bottle washer. Disposal of the `dry' pulp is not always easy; it usually goes to landfill or to incineration.”
"Brewing: science and practice", by Dennis E. Briggs, Chris A. Boulton, Peter A. Brookes and Roger Stevens, 2004, page 764.

Let’s look at the sequence of events in a modern 1950’s bottle washer:

“The most modern machines give a preliminary hot water rinse followed by a caustic soak, then a caustic spray and finally hot and cool water rinses. To ensure effective cleaning as well as the sterility of the issuing bottle it is essential that the temperatures of the rinses and sprays should be sufficiently high. The caustic soak and spray and preliminary hot water rinse should be at least 140º F. and the final hot rinse preferably not less than 160º F. To maintain these temperatures a good supply of steam is needed and sometimes, where bottling stores are working beyond their capacity, the increased demand for the steam boiler renders this difficult, but a drop in temperature may result in the bottles leaving the water in an unsterile condition. The rinse water itself should be free from infecting organisms. Chlorination of the final rinse to an extent of 0.3 to 0.5 part per million is sometimes used, but generally it is preferable to avoid the use of chlorination, unless it is imperative. Nevertheless chlorinated rinse waters can be used without affecting the flavour of the beer, if only the minimum of chlorine necessary is used. With all bottle-washing machines accessibility to interior working parts must be an early consideration. Cleanliness is essential, and scale must be easily removed as its presence impedes the effectiveness of the machines. Ease of working in the case of a breakdown is also important.”
"Brewing Theory and Practice" by E. J. Jeffery, 1956, pages 350 - 351.

They wouldn’t need to chlorinate the water nowadays. Mains water is already full of the stuff. Which is why I find British tap water undrinkable – it’s like drinking a swimming pool.

It doesn’t sound as if much has changed:

“The sequence of operations varies with different washers. A typical system is to soak the dirty bottles in hot water and then pass them through a hot caustic soda solution. Bottles are then successively rinsed with hot caustic solution, hot water, and finally cold fresh water.”
"Brewing: science and practice", by Dennis E. Briggs, Chris A. Boulton, Peter A. Brookes and Roger Stevens, 2004, page 764.

Though Briggs does recommend a warmer temperature for the hot soak, namely 165 – 185º F*.

It’s washing stoppers next.

* "Brewing: science and practice", by Dennis E. Briggs, Chris A. Boulton, Peter A. Brookes and Roger Stevens, 2004, page 764.

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