Today 22 September 2020
Cereal 

Quality of Wheat for Producing Flours

  There are more than hundred varieties of wheat. The varieties have different properties and features and the producer and consumer supply or purchase them based on their aims. Generally speaking, the quality of wheat in terms of the properties of its application is divided into three categories:

1. Quality in Respect of Flour Yielding: Experience has proved that in the wheat grains whose grooves are superficial, the bran is separated from endosperm easily and so the flour yielding is higher. The size of the grain (hectoliter eight) too is important. The bigger, longer, and more uniform the grain is and the less its salts are, the higher is the flour yield.

2. Quality in Respect of Nutrition: Considering nutritional value, the higher nutritional materials specially minerals and proteins is desirable.

3. Quality in Respect of Bakery Value: Different properties of flour for producing better and more desirable bread is called the bakery value of wheat. The desired properties of flour are swelling when dough has been made (getting more voluminous), getting porous with gases, existence of uniform holes of entrapped gas in the dough, good taste, good appearance, and non-being pressed after being baked.

Most properties enumerated above are dependants on the protein existing in the wheat not in their quantity. The principal factors which determine the bakery value of wheat is the quantity and quality of gluten in the grain. The quantity of gluten is mostly determined by environmental factors but it qualitative properties are necessarily influenced by genetic factors. What determines the quantity of gluten most is the period which is needed by the wheat plant to yield ripen grains. The shorter the period needed for getting ripen, the higher is the percentage of gluten in the grain. Wheat earned in dry farming is full of gluten because of high temperature and less water. Durum wheat is not suitable for making bread. However, since the dough of durum wheat is not resilient, absorbs less water, is formed into dough easily, and is overflowing with protein, it is highly suitable for producing macaroni. Degree of being glassy in durum wheat is between 25 and 65 per cent and sometimes even 80 per cent. But, the conventional wheat is less than 25% glassy.

Rainy weather and low temperature generate starchy tissue. The protein of wheat is poor in respect of lysine amino acid but there are sufficient amount of other amino acids such as leucine, isoleucine, valine, histidine, and proline. Generally, the amount of protein in wheat grain is about 9 to 13 per cent. Out of this amount of protein, 3-5 per cent albumin, 6-9 percent is globulin, 30-40 per cent is gliadin, and 40-50 is glutenin. There is a negative correlation between hectoliter weight and percentage of protein. Further, the proteins existing in endosperm consists of approximately equal amount of gliadin and glutenin while the protein existing in germ is albumin, globulin, and proteases.

For assessing the bakery property, there are different methods. The elementary methods are measuring total wet gluten, volume of protein , and time of dough ball spread. For finding the amount of wet gluten, ten grams of flour is weighed and then wash it with water to separate starch from protein. When the separation occurred, protein is weighed and its percentage is calculated. The more wet gluten, the higher bakery value exists.

For finding the volume of protein, 3.2 grams of the flour is put in graduated cylinder and 50 mililiters of ready-to-use bluphenol solution is added to that. The graduated cylinders are closed tightly and are shaken horizontally for 5 seconds till the flour gets into suspension state. The cylinders are put on special shaker and are shaken for five minutes. Now, 25 mililiters of acid lactic-alcohol solution is added to that. Again, it is shaken for five minutes and after 5 minutes, the amount of the sediment is measured.

For finding time of dough ball spread, some dough of flour are formed into ball and the ball is placed in water with temperature of 32 Celsius. The time need for dispersion of ball dough is measured and then, the bakery value is calculated by following relation:

25 X Weight of Wet Gluten + (100 X Volume of Gluten) + (50 X Resistance Time of Dough) = Bakery Value

If the total of above mentioned three factors is more than 4050, the bakery value is very good, between 3000 and 4050 it is medium, and less than 3000 is bad. One hundred kilogram of wheat in terms of its bakery value, yields 15-166 kilogram dough and 114-136 kilogram bread.

Effects of Cereals on Prevention of Gum Diseases

Recent studies show that eating good amount of whole grains may decrease the frequency of oral diseases including gum diseases. The studies made by Dr. Merchant in Ontario University of Canada suggest that any regimes helpful to general health of body are helpful for health of mouth too. The gum diseases may be prevented by diet regime. Diabetes and high value of sugar in blood are among the factors which make the occurrence and intensification of gum diseases more likely. On the other hand, whole grains and fibers having capability of blood sugar direction have proved to decrease the possibility of gum diseases occurrence. Before this study of Dr. Merchant, the relation of whole grain consumption and gum diseases was not been studied.

The mechanism by which grain consumption affects the frequency of gum diseases are as follows: The energy extracted from the grains improves the burning of glucose and this leads to lesser amount of glucose in blood. Lesser amount of glucose in blood decreases the probability of gum diseases in diabetic and non-diabetic persons. Thus, consuming macaroni which is a good source of cereals, grains, and fiber prevents gum diseases.

 

Amount of Vitamins, Minerals, and Fatty Acids

Vitamins Mg/g Minerals Mg/g Amino Acids g/16 g of Nitrogen Fatty Acids %
Thiamin 3.5 K 453 Argenine 2.6 Saturated  
Riboflavin 1.2 P 380 Cysteine 2.2 Mirsetic C14:5 0.1
Nicotinic Acid 5 S 196 Histidine 3.8 Palmitic C18:5 24.5
Pantothe- nic 12 Mg 157 Isoleucine 6.7 Stearic C18:5 1
Biotin 0.1 Cl 76 Leucine 2.3 Other Saturated Fatty Acid 0.2
Proxidin 5 Ca 51 Lysine 1.7    
Folic Acid 1000 Na 24 Methionine 4.8 Unsaturated  
Inositol 2500 Si 12 Phenylalanine 2.8 Palitoleic 0.8
Cyanoco-balamin 0.002 Fe 5 Threonine 1.5 Oleic 11.5
    Ze 5 Tryptophan 2.7 Linoleic Acid 56.3
    Mn 4 Tyrosine 4.4 Inolenic 3.7
    Cu 0.7 Valine 3.3 Other Unsaturated Fatty Acid 1.9
        Alanine 4.7    
        Aspartic Acid 33.1    
        Glutamic Acid 3.7    
        Glycine 11.1    
        Proline 5    
        Serine 4    
Reference: Bajaj, Y.P.S. 1991, Wheat. Narosa-Publishing House-Springer Verlage

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