P/00/01i1 Regulation 3.2 AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Invention Title: A lidding system The following statement is a full description of this invention, including the best method of performing it known to us: 1 A lidding system Field of the invention The present invention relates to a lidding system for the baking of items such as bread and in particular square sandwich loaves of bread. 5 Background of the invention The baking of loaves of bread is traditional carried out by placing dough pieces into a open topped bread tin. As the dough pieces prove and rise during the baking process, the dough rises above the height of the tin to produce a domed shaped top of the baked loaf of bread. 0 More recently, square sandwich loaves of bread have become popular due to their ability to conveniently fit into lunch boxes, toasters and sandwich makers. Square sandwich loaves are formed by placing a simple sheet steel panel, commonly known in the industry as a "drop in lid", on top of the tin. As the dough piece proves and rises during the baking process, it flattens against the lid. To ensure that a consistent square 5 top is achieved, the rising loaf ideally lifts the lid slightly off the bread tin as it bakes. When baking is complete, the lid is ideally 15 to 20 mm above the tin, resting on top of the loaves. Square sandwich loaves are typically produced by placing a sausage shape dough piece into a bread tin (or pan). These tins are strapped together in straps of 2, 3 or more tins and the planar "drop in lid" fits over all 2 or 3 tins to close the tins. ?0 While this lid has been in universal use over the past 50 years or so, it is not without its disadvantages. Firstly, in the proving process, a standard process prior to baking, the dough pieces prove in the tin and rise to just beneath the lid. The height of the dough piece when placed in the oven is critical in producing a consistently high quality product. If the dough height is too low baking bread will not rise sufficiently to be squared off by ?5 the lid. If the dough height is too high, the baking bread will rise too high thereby lifting the lid of the tin too far, thus causing "blow out" of the loaf top. The "blow out" of the loaf top occurs when the top of the rising loaf spreads out laterally against the lid to from an unsightly ledge. The "blow out" may close the air space between adjacent strapped 2 baking tins, causing insufficient heat flow between the sides of adjacent tins sharing the "drop in lid". This causes the sides of the loaves to under bake and hence collapse. The collapsed loaf sides combined with the unsightly top ledge creates a distorted loaf, known as a "key-hole" which is difficult to slice and bag. As a consequence, these 5 distorted loaves may be rejected as waste. Secondary, the baking of the sides of the middle loaf or loaves in the strap can be difficult, especially in non-convection type ovens. To overcome this problem, slots have been placed in the lids, in the areas between the tins, to assist in the convective air flow up between the tins. Despite this, baking dough pieces are often longer than necessary 10 to obtain a crust on the sides of the middles loaf or loaves. As a consequence, the baking quality is diminished by the uneven heat transfer within the oven. This problem is increased in "blow out" loaves where the distorted loaf further restricts convective air flow. It is well known in the bakery industry that sandwich or "squares", as they are commonly 15 known, must be constantly monitored while in the proof stage to ensure that they do not over proof and expand too high in the tins. There is no means of correcting over-proof, as pushing the dough down simply deflates the proof, thus adversely affecting quality. Therefore, there is a need to address problems of "blow out" and uneven baking profiles in the baking of loaves of bread. The present invention is directed to addressing at least 20 some of the abovementioned problems. Summary of the invention According to the present invention, there is provided a lidding system for use with loaf tins in the production of bread loaves including a plurality of lids connected together to cover a plurality of loaf tins, the lidding system being provided with venting regions 25 between the lids corresponding to space between adjacent loaf tins, each lid covering a loaf tin, the lid including four side portions fitting adjacent the interior sides of the respective loaf tin.
3 In a preferred form of the invention, the four side portions of the lid define a void beneath in which the dough is contained. The four side portions fitting within the interior of the loaf tin and adjacent to the walls to close the void. Dough pieces baked under this lidding system rise all the way into the enclosed void and up against the lid. During 5 baking the dough piece first bakes onto the lid shape, creating a crust on the upper portion of the sides of the loaf of bread. When the lid is lifted by rising dough during proofing (in particular over proofing) and baking as the dough expands and the level of the dough rises, the four side portions of the lid remain within the walls of the tin. Preferably the four side portions of the lid may have a lower edge which does not rise 10 above the level of the walls during baking. The additional conductive heat transfer of the side portions to the upper portion of the sides of the loaf of bread ensures the faster formation of a crust, thus preventing "blow out" which occurs in this region when the conventional lidding system is used. The lidding system preferably includes a plurality of lids, wherein the lids are connected 15 together by a connecting bar disposed on the top portion. The connecting bar preferably covers a relatively small area between each of the lids, so as to maximise the air space between the lids. This provides venting regions between the lids corresponding to space between adjacent loaf tins that results in good convectional air flow around the tins during the baking operation. 20 These advantageous features of the lidding system contribute to faster more even baking which is more robust to variations in dough preparation and proofing. This results in the increased production of a more consistent high quality product with lower wastage. In another aspect of the invention, there is provided a loaf tin and lid for proofing and 25 baking bread loaf; the loaf tin including a rectangular base and four walls extending upwardly from the edges of the base for receiving dough; the lid including a rectangular top portion and four side portions extending downwardly from the top portion to define a void beneath which the dough is contained; the four side portions of the lid fitting within the interior of the loaf tin and adjacent to the walls to close the void, 4 In a preferred form, the four side portions of the lid fit within the interior of the loaf tin such that during proofing and baking when the lid is lifted by rising dough as it expands and the level of the dough rises, the four side portions of the lid remain within the walls of the tin. The four side portions of the lid may have a lower edge which does not rise 5 above the level of the walls during baking. In a further aspect of the invention, there is provided a set of vessels for proofing and baking square sandwich loaves, the set including two or more vessels in accordance with the above; and a connecting portion. The loaf tins may be arranged in a horizontal array and held in relative disposition. The lids are arranged in an array complementary 10 to the array of baking tins and held in relative disposition by the connecting portion. In this aspect the lids may be arranged to define venting regions between the lids corresponding to space between adjacent loaf tins. Reference to any prior art in the specification is not, and should not be taken as, an acknowledgment, or any form of suggestion, that this prior art forms part of the common 15 general knowledge in Australia or any other jurisdiction or that this prior art could reasonably be expected to be ascertained, understood and regarded as relevant by a person skilled in the art. As used herein, except where the context requires otherwise, the term "comprise" and variations of the term, such as "comprising", "comprises" and "comprised", are not 20 intended to exclude other additives, components, integers or steps. Brief description of the drawings Figure 1a is a top view of a conventional lidding system. Figure 1b is a side view of the conventional lidding system of Figure 1a for use with the strapped baking tins. 25 Figure 2a is a top view of one embodiment of the present invention. Figure 2b is a side view of the lidding system of Figure 2a for use with the strapped baking tins.
4a Detailed description of the embodiments Figures 1(a) and 1(b) show an existing conventional lidding system for 3 rectangular loaf tins 2 held in position by strap 9 which is a metal (steel) band. The lidding system includes a lid 1 made from a sheet of plate steel material having spacings 3 formed 5 therein and extending through the lid 1. The spacings 3 are positioned on the lid to correspond to the gap between the loaf tins 2 so that air can circulate and rise up 5 between the lids, the present invention enables quicker, more even cooking of the loaf sides particularly of the centre loaf or loaves though conductive heat transfer from the top portion 4 to the side portions 5. The lids of the present invention are designed to enable the side portions to fit into the 5 interior of each of the baking tins 2 and adjacent to the side walls of the baking tins. The baking tins are typically strapped together with a specified spacing between each tin. This is in contrast to conventional lidding systems (Figures la and 1b), where the side portions 7 are designed to slide over the exterior of the baking tins 2. As mentioned above, with a conventional lidding system as shown in Figures 1(a) and 10 1(b) there is no means of correcting overproof, experienced bakers and rigorous control over the dough making and proofing stage is required to avoid excessive wastage due to poor quality product. The present invention provides a means to minimise the wastage through a lidding system which promotes a more robust baking process, which is more forgiving to variations in dough preparation and proofing. Thus, the present 15 invention is particularly advantageous for use in operations employing trainee or inexperienced bakers. In use, dough is placed into the baking tins 2 and placed into the oven. As the dough rises it fills the void 14 which is formed by the top and side portions of each lid. On the occasions when the dough is over-proof, the rising dough exerts vertical force on the 20 lids, thus causing them to rise. The lids may rise up to about 50mm, without excessive "blow out". This is achieved due to the dough first baking to the lid shape, defined by the four side portions 5 and the top portion 4, creating a crust on the upper portions of the sides of the loaf. This is the region of the loaf which is prone to "blow-out". Therefore by forming a crust in the top corner portion of the loaf, of similar width to the 25 bottom corner portion of the loaf, the "blow-out" effect is minimised.