Why you need to know the functions of protein in the food?  

1.    Mayonnaise normally used as a condiment. A LOT of people love it so much. If you are plan to make a mayonnaise, but without protein used as an emulsifier……

After you put in egg protein, what will happen?

Therefore, protein is highly dependent for making a mayonnaise.

2.     Everyone loves ice cream as it contains perfect creamy texture. But if you don’t know the protein’s function, the ice cream will end up like this………

It will looks like a layer of oils on the surface of ice cream. Thus, the apperance is being incluenced.

After the protein added in, it will maintains the structure and volume of air during storage.

3.     Next, we you plan to make a pudding. Without  egg protein in the pudding…….

Let's show the coagulation function of egg protein with pudding!

Egg pudding in a few steps!

Ingredients

2 eggs

400 ml milk

30 g sugar

Steps

1. Put the milk into a pan and turn on the gas. Do not let it boil. Turn the gas off when the milk is just warm.

2. Mix the egg with the sugar.

3. Mix the milk with the mixture of egg and sugar.

4. Put the mixture into the mould.

5. Boil the water in a pot.

6. Put the mixture into the pot and steam for 10 minutes.

7. Finished product.

Title: Protein Chemistry Seminar

Date: 19&20 November 2016

Time: 10a.m.-4p.m.

Venue: Taylor’s University lakeside campus

Register’s venue: Taylor’s University Administration

Register Fee: RM10

Sponsored by: Taylor’s University & School of Biosciences

FREE FOODS are provided! 

                                                         

 
                                           

Function of Protein

Protein is formed when amino acids ( usually less than 50) linked together by peptide bonds in a quaternary structure.

Peptide Bond Formation :

                               R¹                                                                            H    R²

                                |                                                |      |

                  H₃N⁺ -  CN -  C - OH         +        H – N – CH – COO^-     

                                          || 

                                         O

                                                               ||(Remove H₂0)

                                                     R¹                 H     R²

                                                      |               |        |

                                       H₃N⁺ -  CN -  C – N – CH – COO^- 

                                                               ||

                                                              O

There is TWO main type of proteins can be found in food  

   v  Gluten

   v  Egg proteins

Figure 1: Gluten (Canadian Grain Commission  2016)

Figure 2: Egg (NCPTT 2016)

Gluten

Content:

  Ø  Found in the endosperm of mature wheat grain

Figure 3: Gluten in the endosperm of wheat( Canadian Grain Commission  2016)

Function:

    ü Use in dough formation :

    ü Contains gliadins and glutenins ( Canadian Grain Commission  2016)

•    Gliadins facilitate fluidity, extensibility, contribute to bread-loaf volume.
•    Glutenins is responsible for elasticity, cohesiveness and mixing tolerance of dough.

Egg Proteins

Content:

   ü  Egg white - Albumin Protein (NCPTT 2016)

Figure 4: Content of Egg white (NCPTT 2016)

      Ø  Ovalbumin - the most abundant protein in egg white

      Ø  Ovotransferin – act as a metal-chelating antioxidant , bind metallic ions

      Ø  Lysozyme – act as an antibacterial shielf for the egg

      Ø  Ovomucin – responsible for egg-white viscosity

   

   ü  Egg yolk

      Ø  Phosvitin- Emulsifying activity (Samaraweera et al. 2011).

     Ø Lecithin- Improve emulsification, texture and flavour.

EGG PROTEIN

Function of EGG PROTEIN:

Figure 5 : Function of Egg Protein (NCPTT 2016,Nii & Ishii 2005,American Egg Board 2016,Tarleton Academy 2016)

  ü Coagulation

   - Process that results in loss of solubility or a change from a fluid state to a solid state when it is exposed to heat or acid (NCPTT 2016).
               o   Egg white begins to thicken at around 62 °C

               o   Egg yolk begins to thicken at 65 °C

-   - Can affect the texture of food as it can act as a thickening agent due to the coagulation process (NCPTT 2016)

-   - Sugar can delay the coagulation process (NCPTT 2016)

             oIt can decrease the rate of heat denaturation and increase the coagulation temperature.

     - Salts promote coagulation

                                          

Figure 6: The process of protein coagulation(Socratic 2015).

   ü Emulsification

      - Egg yolk is a type of oil in water emulsion

      - Lecithin is an emulsifying agent (Nii & Ishii 2005) 

      - Important process in making salad dressings and whipped topping

                                  Figure 6: The process of emulsifier functions in oil and water.

   ü Foaming

      - Bubbles will be trapped by egg albumen and decrease in size, increase in number after whipping or beating (American Egg Board 2016)

              o Involve denaturation of protein at an air-liquid interface

              o then hydrophobic part of the protein will enter the air

              o the hydrophilic part of the protein remains in the water (Athaualpa 2006)

              o Globulins and ovomucin is responsible for foaming properties of the egg (NCPTT 2016)

      - Salts and lipids can reduce foaming performance by reducing its stability thus the  bubbles formed will collapse more easily

      - Sugar can improve stability of the food product.

      - It is important to dairy desserts such as ice-cream and custard (American Egg Board 2016).

               o Due to its foaming properties

               o It can increase its volume

Figure 7: The process of foaming (A Dash Of Science 2013).

ü ü Enrichment

       - To add colour and nutritional values in sauce (Tarleton Academy 2016).

Figure 8: The process of maillard reaction.

                        

Others function of Protein:

Figure6: Other Function of Protein ((Nii & Ishii 2005, Gorton 2012,British Nutrition Foundation 2016a,Tarleton Academy 2016, Food Info 1999 )

  ü  Emulsification

        - Protein is an amphiphilic substance which contains hydrophobic part and hydrophilic part (Nii & Ishii 2005) 

        - Protein can stabilize oil in water emulsion or air in water emulsion( Nii & Ishii 2005) 

               o by diffusing to interface,

               o unfold 

               o then exposing the hydrophobic group 

               o and interact with lipid

        - Prevent droplet coalescent ( separation of two immiscible phase)

        - It is important to salad dressing

  ü  Gelation
       - Involves denaturation of proteins

       - Gel is a continuous network of macroscopic dimensions immersed in a liquid medium and exhibit no steady-state flow due to water immobilization (Gorton 2012).

       - Gelation can make whey protein in the bakery product starts to bind water and lead to a better mouthfeel and palatability (Gorton 2012).

       - It is important to bakery products

  ü  Bulking  

        - Some Protein can mimic the sensory properties of meat

        - Form the main part of the filling of foods for vegetarians such as cottage pie (British Nutrition Foundation 2016a)

         - Eg. Texture Vegetable Protein

          

  ü  Glaze

         - Enhance the colour of the product

         - Give products a shiny glaze (Tarleton Academy 2016)     

     

  ü    Maillard Reaction
       - A type of non-enzymatic browning

           - Involve the reaction of simple sugars and amino acids

           - Form brown nitrogenous polymers which is called melanoidins (Food-Info 1999)

           - Gives a desirable colour to bread crust and cookies (Food Info 1999)

           - Give a desirable flavour to coffee , cocoa

 - 

Reference:

A Dash Of Science 2013, How do egg whites make a foam?, viewed 11 November 2016,
<http://adashofscience.com/2013/04/04/egg-white-foams/>
American Egg Board 2016, AERATION/FOAMING/STRUCTURE, viewed 8^th November, <http://www.aeb.org/food-manufacturers/eggs-product-overview/functional-properties/39-functional-properties/207-aeration-foaming-structure>

Athaualpa R. 2006, “ALBUMEN PROTEIN AND FUNCTIONAL PROPERTIES OF GELATION AND FOAMING”, viewed 7^th November 2016, < http://www.scielo.br/pdf/sa/v63n3/29835.pdf>.

      British Nutrition Foundation 2016a, Food Functions-Bulk, viewed 8th November 2016,http://www.foodafactoflife.org.uk/attachments/d12facea-6d5a-4f87b3289646.pdf

      British Nutrition Foundation 2016b, Food Functions-Glaze, viewed 8th November<2016,http://www.foodafactoflife.org.uk/attachments/7d85f595-53bd-450e90df0edc.pdf>.

Canadian Grain Commission  2016 ,Gluten's role in bread baking performance, viewed 8^th November 2016,<https://www.grainscanada.gc.ca/fact-fait/gluten-eng.htm>.

Eufic 2010, The Why, How and Consequences of cooking our food, viewed 7^th November 2016, <http://www.eufic.org/article/en/expid/cooking-review-eufic/>.

Gorton L. 2012, Protein's vital role in baking , viewed 7^th November 2016, <http://www.foodbusinessnews.net/articles/news_home/Supplier-Innovations/2012/12/Proteins_vital_role_in_baking.aspx?ID=%7B779890A3-9041-49F4-946A-7FDBB51FAE0D%7D>

NCPTT 2016, Protein Chemistry of Albumen Photographs , viewed 7^th November 2016, <http://albumen.conservation-us.org/library/c20/messier1991a.html>

Nii T., Ishii F 2005, “Dialkylphosphatidylcholine and egg yolk lecithin for emulsification of various triglycerides” ,viewed 7^th November 2016, <https://www.ncbi.nlm.nih.gov/pubmed/15748826>.
Samaraweera, H, Zhang, W,  Lee, EJ, & Ahn, DU 2011, 'Egg Yolk Phosvitin and Functional Phosphopeptides—Review', Journal of Food Science, vol.76, no.7, viewed 11 November 2016,
<http://www.aeb.org/images/Egg_Yolk_Phosvitin_and_Functional.pdf>
Socratic 2015, Can someone explain to me the chemistry of cooking an egg, and how amino acids, functional groups of proteins, and polymerization are used/completed?, viewed 11 November 2016,
<https://socratic.org/questions/can-someone-explain-to-me-the-chemistry-of-cooking-an-egg-and-how-amino-acids-fu>

Tarleton Academy 2016, FUNCTIONS AND PROPERTIES OF

INGREDIENTS, viewed 7th November 2016, <http://www.tarletonacademy.org/images/FUNCTIONS-AND-PROPERTIES-OF-INGREDIENTS.pdf>