Coursework- allergen free products PDF

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Coursework for creating allergen-free products....

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Production of allergen free products - bread Introduction Gluten-free products are consumed for medical reason and for lifestyle choices. A gluten intolerance can cause vomiting and diarrhoea. Coeliac disease, which affects one in a hundred people in the UK (Kent and Sussex Courier, 2013), causes the individual’s immune system to react to gluten; producing antibodies against their own tissues and the protein gliadin (Lorgeril and Salen, 2014). This gives more extreme symptoms and damages the lining of the gut, affecting digestion. Creating products without gluten improves and eases quality of life for those suffering from coeliac disease and gluten intolerances. Bread is an important staple food and producing a glutenfree loaf and a standard loaf, allowed the differences to be analysed. There are nutritional differences between gluten-free and standard breads. The ingredients for gluten-free products are used to create similarity to the standard products, but gluten-free ingredients can have a higher fat content, such as tapioca flour. Fibre, found in wholegrains including strong flour, is replaced with a higher fibre content rice flour. The low carbohydrate content of gluten-free bread can be beneficial to those managing weight or diabetes, and reduces some risk factors of heart disease (Foster, et al., 2003). Table 1: Nutritional Content of Warburton's sliced white bread - standard bread.

Typical Values Energy Fat of which saturates Carbohydrate of which sugars Fibre Protein Salt

Typical Values Per 100g of product 1025kJ 244kcal 2.0g 0.5g 46.4g 3.0g 2.3g 9.1g 0.98g

Per average slice (47.4g) 486kJ 116kcal 0.9g 0.2g 22.0g 1.4g 1.1g 4.3g 0.46g

Reference Intake (Adult) 8400kJ 2000kcal 70g 20g 260g 90g 50g 6g

Table 2: Nutritional Value of Tesco Free From Sliced White Bread – Gluten-free bread

Typical Values Energy Fat of which saturates Carbohydrate of which sugars Fibre Protein Salt

100g contains 844kJ (201kcal) 4.1g 0.3g 32.5g 0.6g 6.4g 5.2g 1.0g

Each slice (approx 42g) contains 354kJ (84kcal) 1.7g 0.1g 13.7g 0.3g 2.7g 2.2g 0.4g

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16002521 Materials and Methods The recipes shown below were used to observe, compare and evaluate the differences: cooking methods and sensory attributes, between a gluten-free bread and standard bread. In producing the gluten-free bread a small Hobart mixer was used, but the standard bread required a large industrial Hobart mixer, to deal with the quantity of dough.

Gluten-free recipe: Figure 1: Recipe for gluten-free bread

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Weigh and mix the dry ingredients in a small Hobart mixer at speed 1: •200g tapioca starch •152g rice flour •18g sugar •6g salt •4g mono-glyceride (GMS) •30g stabilizer (made of powdered egg white, HPMC and Xanthan gum)

Add the following, and continue mixing for 2 minutes at speed 1: •12g yeast •40g oil •100g egg

Add 190g water. Mix at speed 1 for 1 minute, then speed 2 for 2 minutes.

Seperate the mixture into 450g portions, and place into two greased loaf tins

Leave the dough to prove at 37°C for one hour, before baking at 180°C for 35-40 minutes.

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Standard Recipe for white bread: Figure 2: Recipe for standard white bread

Sieve and combine the following in a large, industrial Hobart mixer: •1500g strong flour •30g salt •30g improver

Add 30g yeast to the mix.

Gradually add 840g hot water and mix for five minutes.

Once the dough is warm, remove the dough hook. Turn the bowl upside down on the bench surface; so the dough is covered by the bowl. Leave for 5 minutes.

Divide the dough into five equal, round pieces, around 450g.

Cover the pieces with polythene and leave for 5 minutes.

Place each dough into a greased loaf tin.

Dough processing 4

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Results and Discussion Once cooked there were obvious differences between the breads and consumer’s reaction to the different attributes are shown in figure 3. The appearance of the standard bread, in terms of size and colour, was preferred. The gluten-free bread did not rise as much as the standard bread, due to the quantity of yeast in the standard recipe. Yeast is a rising agent, producing carbon dioxide as it breaks down starch into sugars (Wrigley, 2009). Strong flour has a high gluten content and adding water causes hydration of the gliadin and glutenin proteins; forming gluten. The use of both yeast and strong flour in the standard recipe produces carbon dioxide, which causes leavening: the creation of gas pockets. This stretches gluten complexes and causes dough to rise, giving structure to the bread (Wrigley, 2009). In the gluten-free recipe, strong flour was replaced with tapioca starch and rice flour. Salt enhances gluten; adding strength and effecting colour (Krupa-Kozak, 2012). Sugar and egg also impact the colour of products. The gluten-free bread had a pale crust and crumb colour, whereas the standard bread had a golden crust with a pale crumb; this colour and appearance was preferred. As sugar caramelises, it creates a browning effect in the gluten-free recipe. However, sugar competes for water; hindering the development of gluten and further inhibiting the rise of the dough (Krupa-Kozak, 2012). Egg was only used in the gluten-free recipe, to add moisture; thickening and binding ingredients together, acting as an emulsifier and also to enhance colour and create some browning (Funke, 2009). Mono-glyceride (GMS) acts as an additional emulsifier, which increases gas retention, enabling the dough to rise, creating softness to the bread. Neither of these ingredients were needed in the standard recipe. Gluten is responsible for the crumb texture of bread. The gluten-free bread had a dense, yet soft texture, which made it taste dry; an aspect less liked by consumers. The recipe used stabilizer containing xanthan gum, which gave structure to the bread by preventing the separation of ingredients, allowing the flours and water to bind, and enabling crumb formation. Gas pockets formed, which should create a texture similar to standard bread, but in large amounts xanthan gum makes a dense texture (Shittu, 2009). In comparison, vegetable fat in the standard recipe develops flavour and gives texture; creating a smooth mouth feel, making it taste less dry (Funke, 2009), which was favourable. In bread making, the distinctive aroma is created by the fermentation of ingredients. This gave the standard bread its recognisable malty smell, whereas the gluten-free bread had a more metallic smell. Consumers preferred the aroma of the standard bread, however, in this attribute the breads were more comparable with each other.

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Figure 3: Sensory comparisons between breads

Sensory comparisons between standard bread and gluten-free bread Standard bread

Gluten-free bread

Appearance 10.0 Overall liking

Smell/aroma 5.0

0.0

Aftertaste

Taste

Texture

Conclusion Producing gluten-free products is a complex process, which needs to be carefully controlled to meet the gluten-free requirements as set by the Food Standards Agency: ‘20 parts per million or less’ of gluten (2016: online). Figure 3 shows that each sensory attribute of the standard bread was preferred. Without flour containing gluten it is difficult to produce products with similar sensory outcomes and nutritional content to the standard versions. The consumers ‘overall liking’ was determined by appearance, texture, taste, aftertaste and aroma, and this comparison identified the greatest difference between the two breads.

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References Food Standards Agency. (2016) Labelling of 'gluten free' foods. [Online] [Accessed 23rd November 2017] https://www.food.gov.uk/business-industry/allergy-guide/labelling-of-gluten-free-foods Foster, G, et al. (2003) ‘A randomized trial of a low-carbohydrate diet for obesity’, The New England Journal of Medicine. Volume 348 (Issue 21). Pages 2082-2090 Funke, A. (2009) Emulsifiers in bread improvers and bakery ingredients. Second Edition., Germany. Wissensforum Backwaren. [online] [Accessed 17th November 2017]. http://www.wissensforumbackwaren.de/files/wfb_broschuere27_e.pdf Kent and Sussex Courier. (2013) ‘Coeliac Facts.’ Kent and Sussex Courier. 1st August. Page 10. Krupa-Kozak, U, et al. (2012) ‘Breadmaking performance and technological characteristic of glutenfree bread with inulin supplemented with calcium salts’, European Food Research and Technology. Volume 235 (Issue 3). Pages 545-554. Lorgeril, M, Salen, P. (2014) ‘Gluten and wheat intolerance today: are modern wheat strains involved?’ International Journal of Food Sciences and Nutrition, Volume 65 (Issue 5) Pages 577-581 Shittu, T, et al. (2009) ‘Functional effects of xanthan gum on composite cassava-wheat dough and bread’, Food Hydrocolloids, Volume 23 (Issue 8). Pages 2254-2260. Wrigley, C, et al. (2009) Gliadin and Glutenin: The Unique Balance of Wheat. First Edition., American Association of Cereal Chemists.

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