(a) Keeping ovens, stoves or grills switched on much before they are required for use.
(b) Sometimes cooking range tops are left switched on by mistake when the fuel being burnt is not visible, such as in equipment with solid tops in which a radiant filament is not visible.
(c) Fuel may be wasted if equipment is lighted for full heat irrespective of the size of container in which the cooking is done.
(d) When the temperature of cooking is higher than is necessary for a particular food, wastage takes place. This is also true for extended periods of cooking, which may not be required.
(e) Food cooked straight from the freezer without thawing use up more fuel than if thawed in advance.
(f) Non-seasonal foods take longer to cook and therefore consume more fuel than seasonal vegetables, or tender cuts of meat and so on.
(g) Methods of cooking involving preparation of food long before the time of service, require food to be held hot for longer periods. Besides affecting food quality fuel bills go up.
(h) Use of high wattage bulbs in areas where lesser light can do.
(i) Keeping exhaust fans running when kitchens and service areas are not being used.
(j) Using colours on walls and ceilings, and materials which absorb light instead of reflecting it back for good visibility. This aids to the necessity of providing artificial lighting involving the use of electricity, which could otherwise have been saved.
(k) Up to 30 per cent energy can be saved through good cooking habits.
(l) Use only high efficiency ISI marked gas or kerosene stove.
(m) Use pressure cooker. It cooks faster and saves between 20 to 46 per cent fuel.
(n) Surplus water consumes up to 65 per cent additional fuel. Use optimum water.
(o) Soak dal, rice, etc. before cooking. This reduces cooking lime.
(p) Place a lid on an open cooking vessel or Pan., An open vessel loses heat to the atmosphere.
(q) Regularly clean the burner and trim or replace wicks of kerosene stoves.
(r) Keep frozen food out of the fridge for some time before putting them on the stove.
Around 40 percent of energy is expended in preparing, cooking and serving food. The greatest proportion of this energy is used in the Cooking equipment and much of it is wasted by excess use and poor utilisation, e.g. salamanders and all stoves and ovens being turned fully on as soon as chefs appear in the kitchen, regardless of whether they are required immediately or not.
This type of practice inevitably causes maximum heat to be expended in a short space of time which requires further energy to be expended for mechanical ventilation.
Light diesel oil is cheaper than electricity & LPG, this can be proved by knowing calorific value of fuels and present market price. Calorific value of LPG 11850 K cal/kg Electricity 850 K cal/kw Light diesel oil 19000 K cal/lit
Energy Savings in Food Preparation:
Load and unload ovens, steamers and refrigerated cabinets as quickly as possible and do not leave doors open.
Whenever possible, cover pots and pans while cooling.
Ensure maintenance contract includes adjustment of gas burners.
Install timers to switch off cooking processes automatically.
Use internal thermometers to avoid the necessity to open the door when checking core food temperatures in ovens, etc.
Segregate cooking equipment from refrigeration equipment within the kitchen.
Encourage staff to use high-efficiency modern equipment where there is a choice; pressure cookers, combination ovens, brat pans etc.
(i) Set up a schedule of preheating times for appliances and stick to it, 10-15 minutes preheat period for solid top gas ranges, 5-15 minutes deep fat fryer.
(ii) Cool in the largest volume possible.
(iii) Set thermostat to the lowest temperature that will give satisfactory re suits, lower temperature results in lower energy consumption because less energy will be lost to the surrounding air.
(iv) Plan menues to, as not to over load particular equipment (r) Reduce peak load.
(vi) Practice preventive maintenance. Use baking ovens during no peak demand hours.
(vii) Schedule energy intensive cooking.
(viii) Use solar energy for cooking.
Surface Cooking Units:
(i) Place foil under range and griddle burners
(ii) Cover pots and pans with lid.
They will keep the heated air in and decrease cooking time, less consumption of fuel
(iii) Turn down heat as soon as food begins to boil and maintain liquids at a simmer.
Keeping the heat higher than the boiling temperature, does not cook food faster, it uses more energy.
(iv) Keep all cooking surface clean.
(v) Check regularly all gas units for yellow flames and adjust air fuel ratio. Clean uie burners, pilot lights and orifices with a still wire bi ash.
(i) Group kettles and pots in closed top ranges. Use as little surface as possible.
(ii) Adjust the flame, it is entirely blue and has firm centre cone. The tip of the flame should just touch the utensil bottom.
(iii) Burners should always be small than the kettle or pot placed on them. The diameter of the pot should be about 2.5 cm larger than the diameter of the electric coils or plates.
(iv) Use of flat bottom pots & pans to maximise heat transfer.
(v) Clean off build up of spilled food.
(i) Use warm up time to begin cooking
Start the day’s baking with foods that require the lowest oven temperature.
(ii) Plan baking and roasting operation to use ovens to capacity. Allow at least a 5 cm clearance for air to circulate around pans.
(iii) In roasting, use lowest practical temperature.
(iv) Load and unload quickly to avoid unnecessary heat loss and minimize opening door to check food condition.
(v) Remove boil ovens and spill ovens promptly to avoid building of carbon deposits which reduces efficiency.
(vi) Repair broken door hings and cracks that allow heat to escape. Clear all crumbs and encrusted matter from around the door opening. Do not slam or stand on oven doors.
(i) Clean fan blades regularly.
(ii) Maintenance of the motor should be done regularly.
1) Use microwave ovens for reheating and reconstituting.
2) Wipe up spills frequently.
3) Keep interior surface clean.
4) Never use abrasive.
(i) Turn thermo state up only as high as required to reach frying temperatures.
Preheat time is 5 minutes.
(ii) Load baskets one half to two thirds capacity. Crowded food in basket takes longer time and wasters energy.
(iii) Food must be covered with oil, this reduces energy consumption
(iv) Clean fryers regularly.
(v) Drain fryers regularly.
Food Warmers, Hot Plates, Infrared Lamps, Toasters
(i) Turn on only as needed.
(ii) Turn off at night.
Steam Cookers and Tables:
(i) Use steam cookers for vegetables, rice, pasta, to speed up cooking time.
(ii) Maintain the temperature control on steam tables at a level that will keep food warm without allowing clouds of steam to escape. Clouds of steam waste energy.
(iii) Keep equipment and door seals free of debris to prevent steam leakage.
(i) Coal tired tandoors – At the time of installation, use tire proof bricks and sand to insulate the tandoor. Use coal of high calorific value.
(ii) Now a day’s electric tandoors are available use them.
(iii) Dung, wood fired tandoors are also available use them.
Refrigerators and Freezers:
(i) Thaw frozen food in the refrigerator
(ii) Allow hot food a few minutes to cool before placing it in refrigerator freezer.
(iii) Reduce the frequency and length of the time refrigerator and freezer doors are opened.
(iv) Consolidate goods stored in refrigeration and freezer space when possible.
(v) Schedule fan and condenser cleaning and compressor check up.
(vi) Be sure units are leveled periodically.
(vii) Maintain defroster.
(viii) Keep kitchen refrigerators, water coolers, ice cube making machines away from the heat of kitchen.
(i) Locate hot water boosters with in 1.5 metre of the dish washer to avoid heat loss in the pipes.
(ii) Do not wash dishes until you have a sufficient load.
(iii) Adjust the power dryer.
(iv) Check the flow controls.
(v) Use steam hose if necessary to remove excessive grease.
(vi) Regularly remove water lime deposit from spray nozzles and tanks.
(vii) Check speed reducer on conveyor type dish washers for proper lubrication.
(viii) Keep pressure reducing valves in good condition?
(ix) Check pumps regularly.
Keep clean and regularly maintained; check thermostats and heating controls regularly; turn off after use.
Keep clean, especially door runners; check temperature controls; switch off after use. Do not use for reheating food, maintain lower temperature in plate- warming cabinets.
Maintain regularly; check fan efficiency and suitability.
Clean filters, ducting, fan blades, and fan motors regularly to free them from grease & dust.
Food Service Establishment:
It would therefore be appropriate to list out the possible ways of saving time and energy in a food service establishment. Some suggestions are;
(a) Invest on equipment designed to switch off fuel supply automatically when cooking is done. Examples are equipment fitted with automatic timers on which a time period is fixed by the person who places the dish to be cooked.
(b) Use of thermostats to control temperatures so that higher than necessary temperatures are not used for cooking, holding or storing food.
(c) Using the right size of pans for the quantities being prepared, so that fuel is not wasted in heating up larger vessels.
(d) Heating elements and range tops should be switched off when not required. The hot plates may be switched off a few minutes before the food is done as it retains heat for some time after it is turned off.
Experience with cooking of various dishes enables kitchen staff of judge fairly accurately which food will need to be kept on the source of fuel longer than others.
It is now possible to manufacture pan sensing devices which automatically switch off the fuel source when the pan is lifted from the cooking range. Similarly warming bells are used to remind staff that a dish in the oven has to be checked. In some cases warning lights may be used.
(e) Arrangement of work centres to avoid extra movements.
(f) Efforts to recycle heat given off from kitchens for purposes of raising the temperature of washing water would conserve lot of fuel.
(g) Arrangement of refrigerators away from kitchens would require less electricity to run them efficiently. Also, condensers of cooling equipment should never face the wall, because the heat released has no outlet and tend to raise the temperature of the environment unduly.
Some points to pay special attention go while preparing foods for service:
(i) Collect all equipment and ingredients required before starling work to save extra steps.
(ii) Light burners only after all the ingredients are ready for cooking and pans have been placed in position for healing.
(iii) Extinguish idle flames at once when cooking one item and going for another.
(iv) Once boiling starts, reduce the flame to maintain at boiling temperature. This results in a fuel saving of nearly 30 percent.
(v) The size of the burner or flame should be proportionate to the utensil placed on it. Smaller burners consume 5-6 percent less fuel, and should be made use of when preparing small quantities of food.
(vi) Minimum amount of water should be used for cooking to conserve resources.
(vii) Soak whole cereals and pulses to soften them before cooking to reduce cooking time and fuel.
(viii) Soak all used utensils immediately after use for quick and easy cleaning. This procedure reduces the quantity of detergent required as well as effort required for cleaning.
(ix) Coating of un dissolved salts on the insides of boiling or steaming equipment increases fuel consumption. A good procedure to follow is to clean such equipment regularly with a scrubber to prevent deposits from accumulating in the equipment.
(x) When holding foods hot for service, the best procedure to follow is to preheat the holding equipment before placing the foods in the bain-marie or hot case. If hot foods are placed in a cold holding equipment the fall and rise of temperature not only affects the quality of the food, but more fuel is required to reheat the food.
(xi) Minimising the number of utensils used in cooking saves energy in washing. This can be done by using pressure steamers or cookers, which can be used for processing number of items one after the other before washing it. This can also be done by cutting fruits, for instance, straight into the bowls in which the fruit salad is going to be served.
(xii) Use of labour saving devices cuts down an effort if planned properly. It is clear therefore that effective utilisation of resources is simply a matter of good planning, organisation, and control-in short that is effective management.