It is hardly necessary to stress the importance of bread as an article of food. It is not only consumed in all countries of the world, but it is also the most acceptable form of food there.
Maurizio in his bock "Grain Foods" refers to bread as the emblem of the highest degree of culture, and gives an interesting account of tbe development of bread from the point of view of cultural history.
Now, wheat which furnishes the material for bread is grown all over the world. Depending on the degree of culture achieved, the form given to the food prepared from wheat also varies greatly. But history demonstrates that in any country which aims at cultural advancement, the final food form arrived at, Is bread. It is in view of the foregoing that an account bas been attempted here of the plan for a cottage scale bakery.
There are many kinds of bread peculiar to the respective countries. For example, there are French, Russian, German. British and other bread, each of which has its own characteristics in materials, methods of making and tastes.
Bread is bound to become more popular throughout the world.
Raw Material For Bread
Wheat Flour
Wheat flour, the main raw material for bread may broadly be classified into high protein(protein over 11% , medium protein flour(protein 8-11%)and low protein flour (protein below 8%).
Flour which contains proteins when moistened and beaten , form gluten, which is elastic and so helps to hold the air and carbon dioxide in the mixture and make it light. In bread making the gluten is developed by kneading to form a strong network which sets on baking. Different wheats have varying amounts of gluten but plain flour on the market can be used for bread making, cakes and biscuits.
Whole meal flour can be used for bread making but cakes and pastery will be
coal-se in texture dark in colour.
Generally speaking, high Protein flour is used as a base with medium and low protein floul mixed in appropriate amounts.
yeast
There are two kinds of yeast…raw and dry yeast. It is convenient to use dry yeast because its handling is simple and its preservation easy.
It is important to remember that:
(a)approximately half as much dried yeast as fresh is required in any recipe.
(b) reconstitution is necessary before using dried yeast. This is done by soaking the yeast in lukewarm water (85℉) containing 1/2 oz sugar to 1/2 pint water the water and sugar used for reconstitution should be substracted from the quantities given in the recipe. Sugar can be omitted, but the proving is more necessary than with fresh yeast.
Yeast is a living plant which requires warmth(80-85"F), food and liquid
so that it can live and reproduce The Ingredients and utensils used in bread making and the atmosphere in which the bread is proved must, therefore, be lukewarm; sudden cooling hingers growth and anything hot will kill yeast before it has had time to multiply.
Other Materials
Carbon dioxide is produced in cookery in the following ways:…
(a) By using bicarbonate of soda with something containing acid, such ascream of tartar, syrup or treacle, or sour milk in for example. ginger
bread and soda cake recipes;
(b) By adding baking powder this consists of an alkali and an acid, and is capable of producing a certain amount of carbon dioxide. This is themost accurate method of raising mixtures. All powders should be kept in airtight jars or tins as they quickly deteriorate if allowed to become damp.
(c) By using yeast which feeds on the sugar in mixtures and produces carbon dioxide. Yeast is used in break making.
As for water, there is no problem generally, if city water is available. However. in the case of drawing water from well, hard water is not desirable.
Water with 5-8 pH is best.
As for the materials for packaging, some countries are using polyethylene.
But many use wax paper or grease proof paper.
Process Description
The plant to manufacture breads involves the following sequence of operation;
l. Air Sifter with Pneumatic Conveyor
Flour should flow into the air sifter to be sifted and to eliminate obstructions and is conveyed to the hopper of the mixer by the pneumatic conveyor.
2. Mixing
Dough is made from flour and such materials as yeast. sugar, salt. jot, yeast food etc. This type of mixer has two steps of speed. low and high. For mass production, a high speed horizontal mixer will be suitable. The dough is fermented in the room for 2 to 4 hrs. and again mixed at this stage.
3. Dough Divider
Mixed dough Is weighed and cut by this machine.
4. Rounder
The weighed and cut dough pieces are carried by the conveyor belt of the dough divider and is rounded with this machine.
5. Proofer Machine
Rounded dough pieces are fermented in this machine under an ideal condition, and these are conveyed by a bucket conveyor to be fermented for about 15 minutes.
6. Moulding Machine
Fermented dough pieces are transferred by shooter and moulded by this machine.
7. Second Fermentation Room
Eased dough pieces on racks are carried into this room which has a temperature of 38-40℃ and humidity of 80-85℃ percent.
8. Oven
Fermented dough pieces are baked by this machine.
9. Cooling Conveyor
Baked products are conveyed by this machine and they are cooled during Conveying.
IO. Slicer & Wrapper
Cooled products are sliced and wrapped automatically.
Manufacturing Characteristics of Bread
Bread is products by making a dough from wheat flour and aerating this with carbon dioxide produced by yeast fermentation. Salt is included in the dough because it regulates the rate of fermentation, toughens the gluten, and prevents the bread from being insipid in taste.
The proportion of water need to make the dough varies with the nature of the flour but usually it is in the region of 15 gallons per 280 lbs. of flour.
The proportion of salt used also varies but it is common practice to use about 5 lbs. per 280 lbs. of flour.
The Proportion of yeast needed depends upon the proposed duration of the Fermentation and can be calculated approximately by dividing 12 by the number of hours that will elapse between the mixing of the dough and the placing of the dough in the oven.
The water need to make the dough is brought to a temperature that will give the finished dough a temperature of 75 to 80"F, the exact temperature required depending upon the proposed length of the fermentation. The necessary water temperature can be arrived at by substracting the temperature of the flour from twice the desired dough temperature.
When bread is to be made by what is known as the straight dough system, the required proportions of flour, yeast, salt, water and any other dough ingredients, such as fat, sugar, bread improvers, are mixed together until a homogeneous dough is obtained and this is then covered over and allowed to ferment in bulk. When about three quarters of the proposed bulk fermentation time has passed the dough is very thoroughly kneaded or 'Knocked back', so as to expel much of the gas and to tighten up the dough. It is then covered once more and allowed to complete its bulk fermentation.
At the completion of the bulk fermentation, the dough is divided into pieces
of the required weight, an operation known as ‘scaling’ and each of these pieces is moulded into a ball. After a short period in which they can recover from the action of the scaling and rounding up, the dough pieces are moulded into the shape required for the type of bread that is to be made.
These finally moulded dough pieces are placed in baking tins and allowed a
fermentation period, which is known as "final proof" so that they can become once more inflated with gas. since much of the old gas had been expelled during the moulding operation. The proving period normally occupies from 25 to 40 minutes. according to the type of bread being made.
At the end of this final proof the tins containing the dough pieces are placed in the oven and baked, The baking temperature is 450 to 500℉, and tbe baking time from 40 to 50 minutes.
面包在食品中的重要地位毋需強調。不僅全世界所有的國家消費面包,而且也是那里最受歡迎的食物形式。莫里齊奧在他的《谷物食品》一書中把面包比作人類高度文明的象征,并且從文明史的角度饒有興趣地描述里面包的發(fā)展過程。
當今世界到處種植作面包原料用的小麥。有小麥制成的食品,它所能具有的形式也因各地文明化程度的不同而有很大差異。但是,歷史證明,任何一個旨在文明進步的國家,其最終能達到的食品形式便是面包。
按照上述的觀點,我們在這里嘗試對作坊規(guī)模面包房的制面包方法作一些說明。
不同的國家都有她各自特有的許多種面包。例如,有法國式,俄羅斯式,德國式,英國式以及其他形式的面包,每種面包在原材料、制作方式和口味諸方面都有它本身的特點。
看來,面包終將會在全世界范圍內日益流行。
面包的原料
小麥面粉
小麥面粉是制作面包的主要原料,它大體可分為高蛋白質面粉(蛋白質含量超過11%),中量蛋白質面粉(蛋白質含量8~11%)和低蛋白質面粉(蛋白質含量低于8%)。
面粉中含有好幾種蛋白質,這些蛋白質經和加水攪打后形成面筋。面筋有單性,從而有助于保持空氣和二氧化碳在混合料之中,使混合料變松。在面包制作過程中,面筋靠揉捏作用形成,構成一定強度的網(wǎng)絡,它在烘時固定下來。不同小麥的面筋含量不同,而市場上的普通面粉可以用來制作面包、蛋糕和餅干。
全麥面粉可以用來制作面包,但全麥面粉制的蛋糕和糕點質地粗糙顏色暗。
一般來說,高蛋白質面粉用作一種主要成分,并以適當?shù)臄?shù)量混以中量蛋白質面粉和低蛋白質面粉。
酵母
酵母有兩種:鮮酵母和干酵母。使用干酵母比較方便,因為它貯運簡便,也容易保藏。 以下兩點值得記。
(a)在任何面包配方中,要求干酵母的用量多到約為鮮酵母的一半。
(b)干酵母在使用前必須復原。做法是:將酵母浸泡于(1/2盎司糖對1/2品脫水的) 溫水(85°F);復原用的糖和水,其量應當從配方所給量中扣除.糖可以不加,但對干酵母進行復水活化則比用鮮酵母時更有必要。
酵母是一種植物類生命體,需要溫熱(80~85°F)、養(yǎng)分和液體才會生存和繁殖。因此,面包制造上所用的配料和器具以及面包發(fā)酵所在的周圍氣體都必須是溫熱的;在酵母按時完成增殖之前,突然降溫會妨礙它生長,任何熱的東西又會殺死它。
其他材料
在面包烤房里,二氧化碳的產生有以下幾條途徑:
(a)碳酸氫鈉于某些含酸物質如酒石酸氫鉀、糖漿或糖蜜、或譬如象姜汁餅和蘇打餅配方中的酸乳等等一起使用。
(b)加入發(fā)粉(烘烤粉)。發(fā)粉由酸和堿組成,能產生一定量的二氧化碳。這是使混合面料帶氣鼓起最為準確的方法。各種發(fā)粉如果讓其吸潮就會迅速變壞,所以都應保存在密封的瓶子或鐵罐中。
(c)使用酵母。酵母以混合物中的糖為原料,并產生二氧化碳。面包制作中使用的是酵母。
至于說水,如果有自來水,一般就不成問題。但是,在使用地下井水的場合,若為硬水則不適合。pH5~8的水最適宜。
至于包裝材料,有些國家使用聚乙烯膜。但許多國家則使用蠟紙或防油紙。
工藝過程說明
生存面包的設備涉及以下的操作程序:
1.帶氣力輸送系統(tǒng)的風篩機
面粉流送,進入風篩機,以除去有礙的物質,然后由氣力輸送系統(tǒng)送入混合機進料斗。
2.混合
面團又面粉和酵母、糖、鹽、添加劑、酵母養(yǎng)料等物質制成。這種混合機有低、高兩檔速度。對于大規(guī)模生產,宜用高速臥式混合機。面團在室內發(fā)酵2~4小時后,仍在臺混合機上再次進行混合。
3.面團分切機
將混合好的面團過秤后由本機進行分切.
4.面團搓圓機
過秤和分切之后的面塊,有面團分切機的輸送帶傳送,并由本機進行搓圓.
5.面團發(fā)酵機
搓圓后的面團在本機內于理想條件下進行發(fā)酵,面團由斗式升運機傳送,收到約15分鐘的發(fā)酵作用.
6.面團形成機
發(fā)酵過程的面團由滑槽傳送,并由本機進行成形.
7.二次發(fā)酵室
架子上已膨松的面團被送往本發(fā)酵室,此室的溫度為38~40℃,濕度為80~85%.
8.面包烤爐
發(fā)酵好的面團在此烤爐中進行烘烤.
9.冷卻輸送機
烘烤后的產品由本機邊輸送邊冷卻.
10.切片機和包裝機
對冷卻后的產品進行自動切片和包裝.
面包的生產特點
面包的生產方法是先將小麥面粉制成面團,而后使此面團充以由酵母產生的二氧化碳氣體。面團中還摻進了鹽,因為鹽可以調節(jié)發(fā)酵速率,韌化面筋,防止面包味道變淡。
制備面團所需的用水比例跟著面粉的性質而不同,但通常范圍是每280磅面粉為15加侖.
用鹽的配比也有差異,通常做法是每280磅面粉約用5磅鹽.
酵母的使用比例取決于設定發(fā)酵時間的長短,并且可以粗略地按下法計算:將12除以面團混合到面團入爐兩者之間所經過的小時數(shù)便得.
制造面團由的水要加熱,使最終面團的溫度在75~80°F之間,確切的水溫要求取決于設定的發(fā)酵時間.可將必要的面團溫度乘2減去面粉的溫度便得這一必要的水溫.
當采用所謂直接發(fā)酵面團法制作面包時,先將所需比例的面粉、酵母、鹽、水和其他面團配料(如脂肪、糖、面包改良劑)一起混合,直至得到均勻一致的面團,然后將它遮蓋起來,讓它整塊發(fā)酵.當發(fā)酵進行到預定大塊發(fā)酵時間的3/4時,便對面團進行非常充分地揉捏,即揉緊發(fā)面使發(fā)過頭的回縮,如此驅走大量氣體,縮緊面團.然后再次遮蓋面團,讓其最后完成大塊發(fā)酵.
大塊發(fā)酵結束時,將面團分切成重量合乎要求的小面塊(此操作稱為"面塊定量"),然后每一面塊都經模制成球形.經過一個很短的時間(在此期間,面團會從定量分切和搓圓的影響之后得到恢復)之后,面塊再經模制成合乎待制面包品種所要求的形狀.
將最后成形的面塊放在聽型烤模(烤聽)中,讓其發(fā)酵一段時間,這稱為"最后發(fā)酵",這樣可使面塊再次充氣鼓起,因為成形操作過程中曾驅走許多以前的氣體.此發(fā)酵階段通常需25~40分鐘,視待制面包的品種而定.
最后發(fā)酵結束時,將裝面塊的烤聽進爐烘烤.烘烤溫度為450~500°F,烘烤時間為40~50分鐘.