three typical methods of chiling are employed
1. the use of clean high velocity re-circulating air at low temperatures in mechanical apparatus sparacial mechanical chillers for liquids are available
but these require appropriate cleaning and disinfecting between batches
2. the use of cryogenic approprtus involving the use of non-oxidising
gas at low temperatures
3. the immersion of packed products in a safe and suitable refrigerated liquid
with chilling techniques recipes or ingredients can be applied to a wide
range of both pre-cooked and uncooked and uncooked dishes although
there may be some trouble with the stability. care should be taken to avoid
excessive contact between the sauce and the base of the cintainers to prevent overcooking during
re-heating cooling does thicken sauces and care should be taken to ensure
that the viscosity of the sauces after cooking is slightly thinner than normal. for example concasse or croute bases may be used to insulate
the sauce from the hot container.
reheating of chilled food should begin as soon as possible and no longer
than 30 minutes after the food is removed from the chill ( EITHER bulk chill
secondary chill or chilled trolley) . for reasons of safety and palatability
the centre temperature of the food should reach at least 70c and be maintained at not less than 70c for 2 minutes . once the food has been
heated properly the service of the foods should commence as soon as possible and within less than 15 minutes of reheating . the temperature must not be allwoed to fall below 63c . any meals not consumed should be destroyed and not rrehested or returned to chilled storage. chilled food can be saved for 48 hours for cold food and 72 hours for not meals
cook-freeze
cook-freeze is another catering system based on full cooking followed by fast freezing and storage at controlled low temperature conditions well below freezing point (-18c oe blow ) as long as this storage yemperature is maintained micro-organisms cannot grow. this is subsequently followed
by thorough reheating close to the consumer before prompt consumption.
the food should reach a centre temperature of at least-5c within 90 entering
the freezer and subsequently should reach a storage temperature of -18c. the shelf-life o per-cooked frozed food varies according to the type of food but in general it maybe stored for up to 8 weeks wthout any develop in foods without any significant loss of nutrients or palatability . after that time rancidity may develop in foods with a high fat contact but other foods can be satisfactority stored for longer periods on addition a clear system of coding the containers with product identification batch production and expiry
dataes should be used so that stock can be rotated on a fist-in /frist-out basis.
these two system of catering have a number of similarities in their basic
design and the choice on which to use would depend on the balance of benefits to be obtained for the caterers needs as illustrated in table 7.3 the preservation of food in cook-chill operation is of a limited nature after which it should be destroyed . since the storage life is relatively short the linking of production to service is much tighter than what is needed in cook-freeze operation . in general the production unit would generally produce food
for a known predicted demand 2-3 days in advance working consistently to the produce either much higher wastage or greater shortages in the catering
system than might be encountered in a cook-freeze operation
sous-vide
this allows sauces and entrees to be produced on batches up to 14 days in advance and stored (gehrig 1990) food is bulk chilled and packed in vacuum
sealed bags . typically a production run may be sufficient for four flights . the benefits are said to be that productivity can be increased through the use of
three typical methods of chiling are employed
1. the use of clean high velocity re-circulating air at low temperatures in mechanical apparatus sparacial mechanical chillers for liquids are available
but these require appropriate cleaning and disinfecting between batches
2. the use of cryogenic approprtus involving the use of non-oxidising
gas at low temperatures
3. the immersion of packed products in a safe and suitable refrigerated liquid
with chilling techniques recipes or ingredients can be applied to a wide
range of both pre-cooked and uncooked and uncooked dishes although
there may be some tro