Tatar powder is an acidic white powder. The main purpose of making cakes is to help protein disperse and neutralize the alkalinity of protein, because protein is very alkaline. Moreover, the longer the eggs are stored, the stronger the alkalinity of protein will be, and the food made of a large amount of protein will have an alkaline taste and turn yellow. Adding Tata powder can not only neutralize the alkaline taste, but also make the color whiter. If you don't have Tata powder, you can also use some acidic raw materials such as lemon juice or orange juice instead, but the dosage should be considered because the acidity of these juices is different. Generally speaking, one teaspoon of Tata powder can be replaced by one tablespoon of lemon juice or white vinegar, but the amount of protein should be reduced by about10g. When using white vinegar, don't worry about the taste of vinegar. The alkaline neutralization in protein and the feeling after baking are not very good. Yeast: Yeast is a single-celled microorganism. The basic characteristics of these single-celled microorganisms are: simple nutritional requirements, full utilization of sugars and organic acids, strong reproductive ability, high utilization rate of reducing agents, acid-resistant environment, high content of protein and vitamins, no pathogens and toxicity, low content of lysine and tryptophan in grains, but rich in these substances in yeast; Especially when methionine is added, the available ammonia is about 30% higher than that of soybean. The calorific value of yeast is equivalent to that of beef, and because it is rich in B vitamins, it is usually used as an additive feed for protein and vitamins. It can be used to feed pigs, cows, chickens, ducks, minks and fish, and can obtain good economic effects, such as strengthening physique, reducing diseases, gaining weight quickly, laying more eggs and producing more milk. Yeast is rich in protein, B vitamins, 18 amino acids, fats, sugars, enzymes and some growth-promoting factors, because it can not only promote the growth and development of animals, improve their immunity and feed conversion rate, but also has strong taste and disease resistance. Yeast can be used as a high-quality protein source to partially or completely replace soybean meal, fish and meat and bone meal in feed, so it has been widely used in feed industry and animal husbandry. Custard powder is a kind of spice powder. Powder, light yellow-light orange yellow, easily soluble, suitable for soft, fragrant and smooth hot and cold desserts (such as cakes, egg rolls, fillings, bread, fruit pies, cakes, puddings, tarts and other cakes), mainly taking its special aroma and taste, is an ideal food spice powder. Custard powder series products of Cantonese source brand are indispensable excellent baking products in pastry, dessert and cooking, and are suitable for making all kinds of western pastry, cakes and fillings. The distinctive features of Guangdong source brand instant custard powder are: ready to use, no need to heat, time-saving and convenient; The finished product has fine texture and smooth taste; Color, smell and taste are impeccable; High temperature resistance, frost resistance and stable performance.