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Why do cakes shrink and deform during baking?
1, reason:
(1) It may be that the temperature in the furnace is uneven, and the cakes string up and down, back and forth, which leads to the shrinkage and deformation of the cakes due to vibration and gas loss before forming in the furnace.
(2) Too much sugar is used in the formula, and the specific gravity and viscosity of batter are too high, which affects the formation, expansion and foaming of protein film.
(3) The eggs used are not fresh, the cooking time is too long, the viscosity is reduced, the stability is poor, and it is not easy to swell and bubble.
(4) The proportion of flour used in the formula is too low, the batter structure is not firm, and the gas retention is poor, which is easy to cause the phenomenon of thermal expansion and cold contraction.
(5) Excessive chlorine bleaching of flour leads to a serious decline in gluten strength, which makes the batter's organizational structure unstable and has poor gas retention, and also causes the phenomenon of expansion with heat and contraction with cold.
(6) At the beginning of baking, the oven temperature is too low, and the excess moisture in the cake cannot be evaporated; In the middle of baking, the oven temperature is too high, and the fire is too big, which causes the external coke to be immature, and the cake has too much residual water, so it shrinks when it is cold after baking.
(7) Too much leavening agent is used in the formula, which leads to excessive expansion of the cake, destruction of the cake's organization, unstable structure, decreased gas retention, and contraction when discharged.
2. Improvement measures: (1) Try not to move the cake during baking to avoid collapse due to vibration.
(2) Check whether the amount of sugar in the formula milk exceeds the amount of eggs.
(3) Fresh eggs must be used.
(4) Check whether the formula and the total water amount are balanced.
(5) Don't bleach excess flour with chlorine.
(6) The oven temperature of sponge cake should be 177~205 degrees, and the baking rules should be adjusted flexibly according to different varieties.
(7) Except for low-grade sponge cakes, it is best not to use leavening agents.
(8) Don't stir too much when beating eggs.
Problems and countermeasures caused by improper ingredients in cakes.
The ingredients of the cake are eggs, sugar, flour, etc. As the main raw materials, there are dairy products, leavening agents, flavoring agents and so on. As an auxiliary material. Because of the difference of processing performance of these raw materials, the proportion of various raw materials should also follow certain principles, which is the principle of raw material formula balance, including the balance between dry raw materials and wet raw materials, as well as the balance between strong raw materials and weak raw materials.
Cake raw materials can be divided into the following categories according to their different functions in cake processing:
(1) Dry raw materials: flour, milk powder, leavening agent, cocoa powder, etc. (2) Wet materials: eggs, milk, water, etc. (3) Strong raw materials: flour, eggs, milk, etc. (4) Weak raw materials: sugar, oil, leavening agent, emulsifier, etc.
(a) Dry raw materials and wet raw materials
The dry ingredients in the cake formula need a certain amount of wet ingredients to be wetted before they can be made into cake paste. For example, flour in a cake recipe needs about the same amount of egg liquid to be wetted, but it varies according to the type of cake. For example, the main feature of sponge cake is foam system, and the amount of water can be slightly more; But the oil cake is mainly emulsified system, and too much water is not conducive to oil-water emulsification. The amount of water (percentage of flour) in the cake product formula is: the amount of eggs added in sponge cake is 100%-200%, which is equivalent to 75%- 150%. When preparing ingredients, when the amount of eggs in the formula decreases, milk or water can be used to supplement the total liquid amount. However, it should be noted that the conversion between liquids is not equivalent, and the reduced 1 egg needs to be replaced by 0.75 part of water or 0.86 part of milk, or milk and water are added at the same time in a certain proportion, because the water content of eggs is about 75%, while the water content of milk is about 87.5%. For example, when making a cake in the shape of cocoa, the added cocoa powder can be counted as replacing part of the flour in the original formula, and the addition amount is generally not less than 4% of the flour. Because the water absorption of cocoa powder is stronger than that of flour, it is necessary to supplement the same amount of milk or water to adjust the dry-wet balance. If the dry and wet substances in the ingredients are unbalanced, it will have an impact on the volume, appearance and taste of the product. Too much wet material will form a "wet zone" at the bottom of the cake, and even make some cakes collapse and the product volume shrink; Insufficient wet materials will make the product compact in appearance, rough in internal structure and hard and dry in texture.
(2) Strong raw materials and weak raw materials
The balance of strong and weak raw materials mainly considers the ratio of oil and sugar to flour, and the amount of oil and sugar added to products with different characteristics is different. The basic proportion of oil and sugar in all kinds of main cake products (percentage of flour) is as follows: sponge cake: sugar 80%- 1 10%, oil 5%-10%; Cream sponge cake: sugar 80%- 1 10%, oil10%-50%; Oil cake: sugar 25%-50%, oil 40%-70%. The principle of adjusting the balance between strength and weakness is that when strong raw materials are added to the formula, the balance of weak raw materials should be increased accordingly, and vice versa. For example, if the amount of fat is increased in the formula of fat cake, the amount of eggs should be increased accordingly to balance the amount of flour and sugar. When the amount of eggs increases, the amount of sugar will generally increase accordingly. Both cocoa powder and chocolate contain a certain amount of cocoa butter. Therefore, when these two raw materials are added, the amount of grease in the original formula can be appropriately reduced. In addition, the strength balance can be adjusted by adding chemical bulking agent.
(C) cake ingredients are prone to problems
Whether the cake formula is reasonable and balanced plays an important role in cake making, and also has a great influence on the quality, nutrition and appearance of the cake. The following are all kinds of problems and solutions that are easy to occur when making cakes due to improper ingredients.
1. There are not enough eggs. Eggs and flour are the main materials that make up the cake structure, and eggs play an adhesive role in the cake structure, which can make the cake swell and soften. The preparation of sponge cake batter mainly depends on beating eggs to make it filled with a lot of air, thus making the cake huge. If the amount of eggs is small, the amount of air wrapped in the cake batter will be small, and the volume of sponge cake will not expand enough. As for the preparation of cream cake batter, although it does not depend on the stirring and foaming of egg liquid, it is the cake batter that whips fat and fills the air. At the initial stage of baking, when the temperature rises to the point where the fat melts and shrinks from the oil film to oil droplets, bubbles transfer from the oil phase to the liquid phase, and the protein of eggs also plays a role in stabilizing and protecting tiny bubbles. Therefore, the amount of eggs in the cream cake formula is generally greater than 65,438+00% of the fat content, at least equal to the fat content. Solution: When the number of eggs is insufficient, the number of eggs can be appropriately increased. When the amount of eggs in the cake formula decreases, besides other liquids, a small amount of chemical leavening agent should be added or appropriately added to make up for the deficiency of leavening agent.
The amount of flour is too small. Because the amount of flour in the formula is too small, the cake tissue is too soft to support the quality of the cake itself, which makes the middle part of the top surface of the cake sag downward. Solution: increase the amount of flour or use flour with medium gluten content.
3. Too much or too little water. Keeping enough water content in the cake can make the cake tissue soft and moist and prevent the cake from drying. The total amount of water and eggs in the batter should not be lower than the amount of sugar. If it is too small, the sugar will not melt completely when preparing the dough, and tiny and light spots will appear on the top of the cake. Moreover, the batter of the cake is too thick, which makes the texture of the cake rough and the size of the holes uneven. Solution: appropriately increase the water consumption in the formula. When too much water is added, because the total amount of water in the cake batter is large, the cake batter expands too much in the baking process, and the water vapor condenses into water after cooling, so too much water in the cake causes the tissue to collapse, making its top surface uneven and concave downward.
4. Too many dairy products. Because of the high lactose content in dairy products, it is easy to color when baking. Solution: Reduce the consumption of dairy products appropriately.
5. The amount of sugar is not appropriate. Sugar can soften the gluten of flour, increase the amount of water added and make the cake moist and soft. When the sugar content in the cake batter is high, in the baking process, the cake batter after sugar dissolution is thinner, its volume expansion is also greater, and the fruit is easy to sink to the bottom. Because the volume of the cake expands rapidly during baking, the top surface of the cake tends to sag downward when it cools, and the volume shrinks to form a rough structure. On the contrary, when the sugar content in the cake batter is low, the swelling is small and the surface color of the product is light.
6. The amount of grease is not appropriate. Oil has a strong defoaming effect, which can increase the softness and smoothness of cakes. When making protein cakes, only egg whites are used. Due to the lack of emulsification of egg yolk, you should not be contaminated with oil when stirring protein and sugar to produce foam. When preparing the whole egg sponge cake, we should also prevent oil pollution, otherwise we can't finish beating, foaming and filling the air. The grease in the formula can only be carefully added after the batter is prepared, so that it can be mixed evenly. The amount of grease depends on the percentage of eggs in the baking percentage. When the amount of eggs is above 140%, the oil content does not exceed 40%; When the egg quantity is 1 10%- 140%, the oil quantity can only be about 20%. In the cream cake formula, the oil content is generally lower than that of eggs 10%, and can only be the same as that of eggs at most. Too much grease will also weaken the structure of the cake, causing its top to sink.
7. Improper use of expansion agent. Although leavening agent plays an auxiliary role in the expansion of cake volume, leavening agent has become one of the indispensable auxiliary materials in thicker cake batter. For smaller cakes, the amount of leavening agent should be increased appropriately. However, when the amount of leavening agent is too much, the leavening agent will produce too much gas during baking, which will make the cake too large, and will also affect the top surface of the cake to sag downwards, resulting in rough texture and uneven hole size. Improper selection of leavening agent, such as ammonium bicarbonate, will leave a strong pungent ammonia smell in the cake; Too much baking soda will make the cake alkaline. Solution: use high-quality acid-base compound leavening agent, and the dosage should not be too much.
8. The gluten content of flour is too high and the gluten strength is too strong. When the cake batter is mechanically stirred, it is easy to form more gluten and has strong elasticity, which will affect the expansion of the cake volume when baking. Solution: Choose low gluten cake powder, which has weak gluten content and gluten strength. In the absence of this kind of flour, proper amount of wheat starch can be used to replace part of flour to reduce gluten content.