Problems with streaking on your machine-washed glasses? CESA has the answer…
Q Can you tell me what a gastronorm tray is and how it differs from any other tray?
A The gastronorm system exists to give compatibility between storage containers, cooking trays and items of holding and cooking equipment ranging from ovens to fridges. It is there to give maximum cooking or holding capacity by co-operation between those who manufacture fridges and cookers and those who manufacture the containers and cooking trays. They both work to the same sizing system.
Before the gastronorm system came in a chef might find that an oven shelf was under-utilised because the cooking tray filled only three-quarters of the shelf, and there were similar frustrations with container boxes in a fridge. The tray and containers are fractions or multiplications of the 1/1 size, which is 530mm x 325mm in width and breadth.
Ovens are commonly built to accommodate the 1/1 size, which means the whole of a cooking shelf can be used. But if two separate items are to be cooked on one shelf, the chef can use two 1/2 cooking trays - which are half a full gastronorm size - and still get maximum use from the oven shelf.
As well as the popular derivatives of the standard 1/1 gastronorm widths and breadths listed below, there is also a big selection of depths.
GN1/6 - 175mm x 162mm
GN1/4 - 265mm x 163mm
GN1/3 - 325mm x 175mm
GN1/2 - 325mm x 265mm
GN2/3 - 354mm x 325mm
GN1/1 - 530mm x 325mm
GN2/1 - 650mm x 530mm
Q We sell a lot of fish in the restaurant and my fishmonger has recommended we get a proper fish fridge. What is the difference?
A A fish fridge looks the same as a standard fridge cabinet from the outside, but has deep boxes inside which prevent any ice or liquid seeping out from the fish and contaminating other food in the fridge by drips or through the fishy smell. The temperature of a fish fridge can also be turned down to 1°C or 2°C without risk of damage to more sensitive foods in the fridge.
Q We are disappointed with the inconsistency of cleanliness in the new glasswasher we have put in the restaurant. We are having to frequently re-wash glasses or wipe them clean with a tea towel before we can put them out to customers. Are we paying the price of buying a cheap machine?
A As long as the glasswasher is of commercial specification, the price paid usually reflects the speed, capacity and longevity of the machine more than wash performance, so it is important to look at how the machine is being used first.
There are three main causes of streaking on glasses. The biggest one is the failure to fit a water-treatment system to the water intake for the machine. Mains water contains dissolved salts. While they are less likely to be seen on a plate, they show up clearly as foggy streaks on glassware. The type of water-treatment system a glasswasher needs depends on the level of hardness in the local water, but the manufacturer or installer will be able to advise on this.
Glasswasher detergents don't need to be as powerful as those needed to shift last night's dried-on lasagne, but things like lipstick are notoriously difficult to remove. If lipstick is staying on the glass after a wash cycle, then talk to the supplier of the detergents or, better still, use the ones recommended by the manufacturer.
CESA, the Catering Equipment Suppliers' Association, has a huge amount of buying and using advice on its website. Visit www.cesa.org.uk and click on the link "CESA Buying Guides".