Course:FNH200/2013w Team20 GlutenFreeBread

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Introduction

Bread was originally found more than 5,000 years ago. The loaves and wheat were found in ancient Egypt. [1] In modern time, variety of breads were baked and consumed by everybody. Normally breads had Gluten in them, but recently Gluten Free Bread has been invented. Many people favour to consume Gluten Free Bread. What is Gluten Free Bread? What are the differences? What makes Gluten Free better? We discovered Gluten Bread can affect someone with Celiac Disease. This wiki page will cover all the important components for the Gluten Free Bread.

Gluten

What is Gluten?

The proteins that make up gluten

Gluten is a protein composite that is formed by four proteins: albumins, glutelins, globulins, and prolamins. [2] True gluten is a protein composite found in wheat, and it is composed mostly of gliadin and glutenin (prolamin and glutelin proteins respectively). However, gluten is found in many grains like rye and barley. [3]

Gluten gives dough its elastic properties, which will later give the structure and chewiness of baked bread. As dough is kneaded, the gliadin and glutenin proteins join together. Gluten helps a loaf of bread keep its shape because as bread is baked, the proteins thicken and trap carbon dioxide that is produced by the yeast. If there is too little gluten in the bread flour, the final product will be too dense and crumbly. [2]

Gluten Functions

Gluten can be found in a wide variety of food products for different reasons. Gluten can be used to:

  • Add texture and chewiness to baked goods.
  • Thicken soups, gravies, and sauces like ketchup and salad dressings.
  • Enhance flavour in bouillon, spice blends, and other foods such as coffees, dairy products, vinegars, and liquors.
  • Act as a stabilizer ingredient for sealing envelopes. [2]
This is a short video about the science of gluten. This compares the amount of gluten protein in cake flour and bread flour, and how that can give different consistencies.

Nutrition

Diagram of the normal digestion of gluten

There is a perception that gluten-free foods are in general, healthier alternatives that can assist individuals with weight loss. Conversely, gluten-free bread does not necessarily provide a healthier alternative, as they typically have higher or equivalent caloric values when compared to regular white bread. Furthermore, there is no published data supporting such weight loss claims and some studies have shown that a gluten-free diet may actually worsen a person’s BMI[4]. One of the main concerns is that most gluten-free breads are made from flours and starches, meaning that these breads will exhibit a high glycaemic index[5]. Nutritionally, gluten-free breads when compared to their regular counterparts, lack fibre and numerous micronutrients such as iron, B vitamins, folic acid, niacin and riboflavin[6]. This has led many manufacturers to enrich their products with vitamins and minerals to fill this nutritional gap.

Normal Gluten Digestion

During the normal digestive process, gluten dissolves into the proteins gliadin, glutenin and other nutrients when digested[7]. After passing from the stomach into the small intestine, the mucosa has lining cells that absorb the gliadin from the bowels[7]. These are the cells that begin metabolising gliadin and because the gliadin is too large to pass through the intestinal wall; it can only enter our bloodstream through this digestive process[7]. During this process, tissue transglutaminase begins breaking down some of the amino acids on the gliadin[7] and the end result is “deaminated” gliadin that then moves on to other cells for further digestion[7].

How Gluten affects people with Celiac Disease

People with celiac disease can trigger an autoimmune response within the body when they ingest a small amount of gluten. This means that the body will reject the proteins instead of absorbing them and, this results in damage of the villi lining the small intestine. If left untreated, this can cause inflammation, diarrhoea, bloating, irritable bowel syndrome, ulcers, intestinal cancer, anemia, and other nutritional deficiencies[8]. Currently, Celiac disease affects approximately 1% of the U.S and the U.K., and this number is continuing to rise.

Thus, Gluten-free diets are beneficial for people with celiac disease or for people with gluten sensitivity. It may also be suitable for persons with other chronic autoimmune disease conditions such as psoriasis, rheumatoid arthritis, and type 1 diabetes [9].

Controversies

  • Some celebrities are promoting a gluten free diet as a way for weight loss, however there is no research to show this is true. The reason people lose weight is most likely because they stop eating cakes and high fat pastas that contain gluten, and not the gluten itself. [10]
  • Some food manufacturers are putting “gluten free” on their labels even though the foods naturally do not contain gluten. This creates confusion for many consumers as they believe that a gluten free diet is healthier, even though they do not have celiac disease. [11]
  • Some companies are selling pills that they claim to prevent celiac symptoms. These tablets contain the enzymes amylase, glucoamylase and dipeptidyl peptidase-4. These enzymes do break down some gluten molecules, but very little and are not proven to work. These would be dangerous for someone with celiac disease to use, and should avoid them. [12]
  • A gluten-free diet is something needed and recommended for someone with celiac disease, but is not healthy for someone else to do. A gluten free diet that consists of using rice flour or potato flour has relatively lower levels of nutrients like iron, B vitamins, and folic acid. [12]
This is a short video that about the truth behind the gluten free controversy. This talks briefly about celiac disease, and why people without celiac disease should not go on a gluten free diet.

Processing Methods: Baking without Gluten

Baking bread without gluten can be challenging because gluten proteins provide the structure that holds the loaf together and traps gases given off by leavening agents. It is the elastic nature of gluten which allows the dough to rise and to expand in the oven. However, improvements are constantly being made to the texture of gluten-free breads as new ingredients and manufacturing techniques are developed. The desirable properties of gluten can be approximated with the combination of gluten-free flours and gums to create a loaf with good volume, softness and texture.[13]

Ingredients

The essential ingredients of bread dough that are required for the principle fermentation process are: Flour, Yeast, Salt, Water.

Flour (Starch)Flour is the key ingredient that adds bulk and structure to bread. Gluten-free bread is made with ground flours from a variety of gluten-free materials such as:

  • Almond
  • Amaranth
  • Buckwheat
  • Brown rice
  • Chickpea
  • Coconut
  • Corn
  • Garfava
  • Millet
  • Potato
  • Quinoa
  • Sorghum
  • Soy
  • Tapioca
  • Teff
  • White rice


Since these flours lack gluten, they do not provide the same elastic matrix when mixed with water and it can be difficult for them to retain their shape as they rise and they may be less "fluffy". This is the reason why Gluten free bread is described as more dense and lacking in the light texture that we associate with wheat bread. However, additives that are used to mimic the elasticity, chewy texture and fluffiness properties of gluten are;


  • xanthum gum
  • guar gum
  • hydroxypropyl methylcellulose (HPMC)
  • corn starch
  • eggs
  • fruit pectin


The most common binder in gluten-free baking are eggs. Eggs replace the binding function of gluten and provide improved structure and texture to gluten-free bread. Eggs also have a drying effect on bread, which helps retain moisture. Besides eggs, guar gum and xanthan gum are two starch-based products that are also often used to bind and thicken gluten-free bread. These products are largely interchangeable and are used to add volume and texture[14]. Traditionally used in making jams and jellies, fruit pectin can also be added to help maintain moisture in the finished product.


Yeast. Yeast is the driving force of fermentation, the fundamental biological process in bread making. Baker's yeast is name of the common strain of yeast used in baking and belongs to the Sacchromyces cervisiae species[15]. This is the same species but different strain of the yeast used in alcoholic fermentation, which is called Brewer's yeast. Baker's yeast is used as a leavening agent in bread making. It converts fermentable sugars in the dough into carbon dioxide gas. The carbon dioxide makes the dough rise which contributes to the light and airy texture. The by-products of fermentation give bread it's characteristic flavour and aroma. The yeast continues to grow and ferment until the dough reaches around 46°C at which temperature yeast dies [16].

All brand-name packaged yeasts sold in North America are gluten free with the one exception of Brewer's yeast. Brewer’s yeast is not normally considered to be gluten free. It is a byproduct of beer making that is used to add flavour and is usually contaminated with barley. Otherwise, regular yeast is gluten free so those suffering from celiac disease or gluten intolerance can safely use it for baking [17]


Other Ingredients:

  • Fat (butter/vegetable oil): contributes to the softness of bread, crispiness of crust, and shelf-life
  • Flour Treatment Agents: Vitamin C is commonly added to flour to improve volume, softness, and crumb structure
  • Emulsifiers : provide dough stability, crumb structure, loaf volume, and softness
  • Enzymes : processing aids to supplement naturally present enzymes in the flour. There are several enzyme catalysed reactions that occur during breadmaking.Starch breaks down into sugar. Sugar breaks down into simple sugars that are necessary for yeast to react with during fermentation. [18]


Key Steps

1.Mixing/ Kneading [19][20] Once the ingredients have been measured, they are mixed to form dough and the dough is kneaded. Kneading involves pushing and pulling the dough with the original purpose of stretching and strengthening the gluten in the dough. When stretched, gluten will trap the carbon-dioxide bubbles produced by the yeast during fermentation, allowing the bread to rise. In the case of gluten-free bread, kneading is still important to incorporate gums and other gas-retaining additives that mimic the properties of gluten.

Different recipes include specific instructions for how and when to add ingredients. However, two important rules of thumb can be used during this step. First, prevent the salt from coming in direct contact with yeast. It is best to add salt to the dough after the yeast has already been mixed into the flour because yeast has a high sensitivity to salt and can be killed. The second pertains to the temperature of water added to dough: Cool, room-temperature, and warm water are fine, but ice water and hot water (anything above 120°F) risk killing the yeast. Using cold water will take the dough longer to rise because it slows down the fermentation process.

Bread machines, stand mixers, or kneading by hand are all acceptable methods. However, when kneading by hand it is easy to add too much flour, which can dry out the dough


2.Proofing/ Fermenting

The next step is called "proofing," or "the first rise." This is the main fermentation and is essential for developing the bread's structure and flavour. During this step, the yeast is activated by the liquid and begins to feed on the sugars from flour, releasing carbon dioxide bubbles. Replacement gum products trap these gas bubbles, which would be trapped normally by gluten. Also, more alcohol and acids are produced, which flavor the bread. The dough needs to be covered during proofing to keep its surface soft and moist. Proofing should also be done in warm room temperature, ideally 75°F to 80°F. Fermentation produces heat, so the maximum temperature should be 85°F. Temperature higher than 90°F can result in off flavors.

Dough is sufficiently proofed when it has doubled in size. To test by touch, the dough is sufficiently proofed when if poked it holds the depression of the fingertip. Breads vary in the number of times they are proofed. A simple bread such as focaccia might only be proofed once, but a more complex-flavored bread, such as a rye loaf could be proofed as many as 3 times.


3.Baking After proofing, the dough is shaped and ready to be baked. The goal of baking is to "gelatinize" or cook the dough and to achieve good volume and an attractive crust. Bread benefits from an immediate hit of strong heat right at the beginning of baking. Always preheat the oven to the appropriate temperature. Different types of bread bake at different temperatures and the recipe should give the exact temperature to use. Generally, baking at lower temperatures results in thicker crusts and prevents overbrowning. To get the most volume from your bread, you need to slow down the formation of the crust, the slower the crust forms, the more time the dough has to expand.


4.Cooling & Storing

Once bread is removed from the oven, it should be placed on a cooling rack to allow air circulation to prevent the crust from becoming soggy. It is important to allow bread to cool all the way to complete the cooking process before cutting and storing. Bread baked in a loaf pan can take as long as 1 hour and a large free-form loaf can take as long as 1 1/2 hours to cool.

The shelf life of bread is affected typically by the fat content. In some commercially made bread, vinegar is added to maintain freshness. Store the bread in an airtight container or bag at room temperature. Bread should not be stored in the refrigerator as the starch will crystallize and the loaf will go stale more rapidly. Bread can also be frozen and if well wrapped can last for at least 3 months.

This video shows how bread is commercially manufactured. Keep in mind it is demonstrating how regular non-gluten-free bread is made, however, the process of making gluten-free bread follows the same essential steps of mixing/kneading, proofing, baking, and cooling.

Methods

There are two main methods of making bread:

Bulk Fermentation Process (BFP)

The more traditional method of Bulk Fermentation Processing involves mixing ingredients to form dough and then leaving the dough to ferment for up to three hours. During this time the yeast is activated and changes the dough from a short dense mass into an elastic dough.

Chorleywood Bread Process (CBP)

The Chorleywood Bread Process is a modern process typically used by large commercial bakeries. CBP utilizes high speed mixing to develop the dough for proofing and baking. This process of rapid kneading is designed to reduce the lengthy bulk fermentation and will take around 4 hours from start to finish. Other than mixing and bulk fermentation, all other parts of the bread making process – dough dividing, proofing, baking, cooling and slicing are the same as any other method. Flour treatments agents, fats, or emulsifiers are typically added to aid in this process[21].

Canadian Specific Food Standards, Regulations, and Guides

Food Dietary Use

As defined in B.24.001 of the Food and Drug Regulations (FDR) (2014)[22] constituted by the Government of Canada, “Food for dietary use” is food intentionally processed or made for a people with “physical or physiological conditions” due to a disorder, disease or injury or to achieve a certain effect that requires controlled consumption of foods. The applicable foods are and listed in Division 24 of the FDR.

The FDR Definition of Gluten

According to section B.24.018 of the FDR (2014)[23], it is illegal to label, package, market or advertise products in a way that implies it is gluten-free when it contains gluten proteins. The following definition of “gluten” is covered by the subsection B.01.010.1(1)[24]. The term "gluten" includes any gluten protein from the grain of any of the subsequent cereals or hybridized strain developed from at least one of the subsequent cereals: barley, oats, rye, triticale, or wheat, kamut or spelt. As aforementioned, oats do not naturally contain gluten but are often contaminated during processing in plants that do process other gluten-containing products. Furthermore, any altered gluten protein, including but not limited to gluten protein fraction, imitated from the previously listed cereals or their hybrids strains are also considered gluten.

Health Canada's Position on Gluten-Free Standards

Even though the FDR did not set a threshold for gluten content in gluten-free products, Health Canada recognizes that there are scientific findings suggesting gluten content below 20 parts per million (ppm), which is the smallest traceable amount of gluten possible with current technology, is safe for the majority who have Celiac disease (Codex Stan 118-1979, 2008)[25]. Therefore, if any added ingredients contain gluten ( ie. in seasoning) that would result in the overall product exceeding the 20ppm limit, gluten needs to be included in the ingredients or in the “contains” statement (Health Canada, 2012)[26]. In this case, the product cannot be labelled as gluten-free unless a later process is able to extract the gluten from the added ingredient. These are the criteria Health Canada, which is the Federal division responsible for helping Canadians improve and maintain health, currently follows when inspecting gluten-free products.

Team 20 Video

This is the video we created to talk about the main points about gluten free bread.

Final Exam Question

Given what you learned about the main ingredients in bread...

a.Name and describe the phenomenon that occurs to the dough when baked in the oven.

b.What preservation method do you recommend to ensure that the quality of the bread is maintained? Why might storing the bread in the refrigerator be a poor storage method?

c.What ingredient is responsible for the fermentation process in bread making? Why is fermentation essential?


Bonus Question: The bread dough is considered a [I. colloidal dispersion] while the final baked product is a [II.colloidal dispersion]

  • A. I.foam II.solid foam
  • B. I.foam II.foam
  • C. I.gel II.solid foam
  • D. I.foam II.solid emulsion


'Answers:

a. Gelatinization - during baking, the crystallized structure of starch granules from the flour absorbs water molecules and swells. This contributes to the moistness of the bread.

b. Freezing, will slow the rate of staling in bread by freezing/trapping the water molecules within the starch matrix. Starches can lose some of their water holding capacity during refrigerated storage through the phenomenon known as retrogradation. Starch molecules will orient themselves back into their crystalline structures leading to a squeezing out ("syneresis") of water and a loss of moisture in the bread.

c.Yeast. Without yeast and fermentation, CO2 gas molecules will not be produced and trapped within the dough and therefore the bread is unable to rise and form the desirable product so many people enjoy!

Bonus: A

Reflection

As more health concerns arise, it is expected that the food industry will take advantage of them by marketing all sorts of “food for dietary use” to us, consumers. And while it might only be beneficial to a certain category of people, for the sake of profit, large corporations would often find ways to convince everyone that we need it. In this situation, it will be our responsibilities to understand the background of what we eat; it is, ultimately, our decision to either believe what the media says or ask our own questions.

The case of “gluten-free diet” is a prime example. It started out as a good notion to offer celiac disease victims with a wider variety of food choices, but soon it was misunderstood as a weight-losing diet. The internet began rumours that eating gluten-free is a good way to “shape up” and even the celebrities joined in. However with further research, one would find that going on such a diet without having celiac disease could potentially result in weight-gain instead, not to mention the reduced nutrients in comparison with regular gluten containing products. It is perhaps a good time to begin critically thinking about our food rather than taking what the big corporations feed us, whether it is innutritious food or just plain lies.

References

  1. History of Bread 1. Botham's Educational Pages. Retrieved from http://www.botham.co.uk/bread/history1.htm
  2. 2.0 2.1 2.2 Kietzman, Shannon. (2014) What is Gluten? wisegeek. Retrieved from http://www.wisegeek.com/what-is-gluten.htm
  3. Castro, Joseph. (2013) What is Gluten? livescience. Retrieved from http://www.livescience.com/39726-what-is-gluten.html
  4. Gaesser G., Angadi, S., (2012), Gluten-Free Diet: Imprudent Dietary Advice for the General Population?, Journal of the Academy of Nutrition and Dietics, Vol. 112, No. 9, page 1332
  5. Fugo, J., (2013), Gluten-Free Bread: Why are you STILL eating it?, Gluten Free School, retrieved from: http://www.glutenfreeschool.com/2013/04/29/gluten-free-bread/
  6. Anderson, J., (2013), How Do Calories in Gluten-Free Foods Stack Up?, About.com, retrieved from: http://celiacdisease.about.com/od/sideeffectsofthediet/a/Calories-In-Gluten-Free-Foods.htm
  7. 7.0 7.1 7.2 7.3 7.4 Petersen V., Petersen R. (2009), The Gluten Effect: How "Innocent" Wheat Is Ruining Your Health, True Health Publishing, page 28
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  10. Johnson, Gail. (2013) Gluten-free movement growing amid controversy. Straight. Retrieved from http://www.straight.com/life/340926/gluten-free-movement-growing-amid-controversy
  11. Gold, Sarah. (2013) The Gluten Controversy Continues. ASN. Retrieved from https://www.nutrition.org/asn-blog/2013/12/accn-2013-the-gluten-controversy-continues-1/
  12. 12.0 12.1 McCardle, Guy. (2011) Gluten Free Diets: Fad vs Fact. Celiac. Retrieved from http://www.celiac.com/articles/22726/1/Can-Enzyme-Supplements-Really-Break-Down-Gluten/Page1.html
  13. F. Watson, M. Stone and M. Bunning (2013). Gluten-Free Baking. Retrieved from: http://www.ext.colostate.edu/pubs/foodnut/09376.html
  14. Gallagher, E. Gormley, T.R. Arendt, E.K. (2004). Recent advances in the formulation of gluten-free cereal-based. products. Trends in Food Science & Technology. 15: 3. 143-152. Retrieved from: http://www.sciencedirect.com.ezproxy.library.ubc.ca/science/article/pii/S0924224403002590
  15. Young, Linda; Cauvain, Stanley P. (2007). Technology of Breadmaking. Berlin: Springer. p. 79
  16. Baking Industry Research Trust. (2014). Yeast Information. Retrieved from: http://www.bakeinfo.co.nz/Facts/Bread-making/Bread-ingredients/Yeast
  17. Dekker, C. (2013). Is yeast gluten free? Retrieved from: http://gluten-free-blog.thebestglutenfreerecipes.com/is-yeast-gluten-free/
  18. Baking Industry Research Trust. (2014). What happens without Gluten in Bread? Retrieved from: http://www.bakeinfo.co.nz/Facts/Gluten/What-happens-without-gluten-in-bread-
  19. G. Stephen Jones (2012, July). How to make Bread: The Reluctant Gourmet. Retrieved from: http://www.reluctantgourmet.com/how-to-make-bread/
  20. Laucke Flour Mills (2014). Bread Making Process. Retrieved from : http://laucke.com.au/baker-s-corner/bread-making-process/
  21. The Federation of Bakers: The Bread Industry: retrieved from: http://www.bakersfederation.org.uk/the-bread-industry/how-bread-is-made/production-methods.html
  22. Food and Drug Regulations. (2014). Section B.24.001. Retrieved from http://laws-lois.justice.gc.ca/eng/regulations/C.R.C.,_c._870/page-175.html#h-128
  23. Food and Drug Regulations. (2014). Section B.24.018. Retrieved from http://laws-lois.justice.gc.ca/eng/regulations/C.R.C.%2C_c._870/page-177.html#docCont
  24. Food and Drug Regulations. (2014). Subsection B.01.010.1(1). Retrieved from http://laws-lois.justice.gc.ca/eng/regulations/C.R.C.%2C_c._870/page-14.html#docCont
  25. Codex Stan 118-1979. (2008). CODEX STANDARD FOR FOODS FOR SPECIAL DIETARY USE FOR PERSONS INTOLERANT TO GLUTEN. Retrieved from http://www.codexalimentarius.net/download/standards/291/cxs_118e.pdf
  26. Health Canada. (2012). Health Canada’s Position on Gluten-Free Claims. Retrieved from http://www.hc-sc.gc.ca/fn-an/securit/allerg/cel-coe/gluten-position-eng.php