Baking
Practical Action
have gas, or it is too expensive, the next preferred option is electricity, especially if it is produced by
hydro-electric power generation or other renewable sources. Solid fuels may be the lowest-cost option
in countries that have significant coal reserves or extensive local forests for wood or charcoal
production. Traditionally, wood has been cheap or free and hence widely used in bakery ovens, but
deforestation in many countries has resulted in legal restrictions on its use and/or increased costs.
Charcoal and coal are often more expensive than wood, but they produces an intense heat with little
smoke. All solid fuels require considerable skill and experience to control the fire, and hence the
temperature in an oven: a careless or unskilled oven operator can waste large amounts of fuel and
also produce products that have inconsistent quality. Liquid fuels such as kerosene or diesel are not
widely used to fuel ovens because they risk contaminating products with off-odours (other liquid
fuels, such as petrol, should never be used because of the risks of fire and explosions).
Worked example: Calculating the size of bakery equipment
A small bakery expects to sell 250 loaves per day, with each loaf weighing 500g. Dough is mixed for
15 minutes, making it possible to mix 3 batches per hour, and a total mixing time of two hours is
allocated per day. Wastage during dough preparation is estimated at 12% and the weight loss from
dough during baking is 10%. Each batch of bread is baked for 20 minutes (i.e. 2 batches per hour)
and a total of five hours per day is set aside for baking. Calculate the minimum size of the mixer and
the oven that would be required.
The amount of dough required per day
Plus extra to take account of losses
Therefore the amount mixed per hour
And the size of the mixer is
The capacity required for the oven
And the oven should be able to bake
= 250 x 0.5 kg = 125 kg
= 125 + (125 x 12%) + (125 x 10%)
= 125 + 15 + 12.5 = 152.5 kg
= 152.5/3 = 50 kg per hour
= 50/2 = 25 kg (i.e. a bowl size of 30 kg to avoid
over-filling).
= 250/5 = 50 loaves per hour
= 50/2 = 25 loaves per batch.
Packaging
The types of packaging used for bakery products depend mostly on their required shelf life: those
with a shelf life of a few days, such as cakes, flatbreads or bread, need minimal packaging, such as
simple paper wraps or polythene bags for hygienic handing and to protect them from dust or other
contaminants during retail or food service sales. Fragile products such as cakes or macaroons may be
sold in cardboard cartons. Bakery products are usually distributed in trays or cardboard boxes.
Plastic trays that are easier to clean have now largely replaced wooden trays. Products with a long
shelf life, such as biscuits and crackers, require protection against breakage; picking up moisture
that would lead to softening; and exposure to heat, light and air that would lead to development of
rancid off-flavours. At a small-scale, biscuits may be packed into biscuit tins, jars, or cartons that
have plastic inserts to hold the biscuits in place during distribution. The biscuits are filled by hand
and the cartons are covered with moistureproof, airtight plastic film and heat-sealed. They are then
contained in corrugated cardboard boxes or other containers to protect them against breakage. Long
shelf life bakery products may also be packed in ‘modified atmospheres’, which are packs that
contain a high concentration of CO2. For example, this prevents mould growth on cakes and
increases the shelf life to 3-6 months; and other bakery products have their shelf life increased from
a few days to 3-4 weeks. However, the cost modified atmosphere packing equipment and an
available supply of CO2 gas may be too expensive for many small-scale bakeries.
Product safety and quality assurance
Baked products rarely cause food poisoning because the heat of the baking process kills most micro-
organisms or reduces their numbers to safe levels. However, bakery products that contain meat,
vegetable or cream fillings have the potential to contain food poisoning bacteria if they are not
handled correctly and stored under refrigeration. Contamination may also arise after baking, caused
by dirty slicing machines or poor staff hygiene. Freshly baked foods should therefore be handled
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