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Fats&oils in bakery products.

Present by:
Dr. Osama Aladl
COO - Modern Bakeries Co.

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Fats&oils in bakery products.

  1. 1. By: Dr. Osama Aladl COO - Modern Bakeries Co. PhD ; Influence & stability of Fatty matters in some Bakery products. MSc ; chemical, physical and technological studies on wheat germ. CQM; American Society of Quality. TQM; American University in Cairo
  2. 2. Why fats are important for bakery products? 1-Fats representing high portion as volume from the total ingredients used as it reached 25-35% in some products (cake)……storage capacity, safety stock, process flow,…. 2- They represent high ratio as a value of money from the total cost of raw materials as their price is almost triple the flour price…….Running cost, standard cost of raw materials, profit margin, losses cost,…. 3- Fats play very essential roll in product structure and shape of some bakery products and the texture of all bakery products that they involved in.
  3. 3. 4- The fats are one of the main ingredients that build up the eating quality profile as it affects the product taste, flavor, softness, texture, color,….etc. 5- The shelf life of bakery products depends on the type and quality of fats used in it…….. product image, returns, flexible distribution. Continue: Why fats are important for bakery products?
  4. 4. What are Fats & Oils ? * Belong to the second major class of organic compounds, .Lipidselectively called * Fats: Solid/ Plastic at room temperature while oil: Liquid. * Insoluble in water and soluble in such organic solvent as ether & chloroform. * They are classified into three main groups based on their chemical & physical properties.
  5. 5. Simple Lipids - Represent the largest and most important members. - Contains only C,H,O - By complete hydrolysis yield only fatty acids and glycerol. Compound Lipids - It contains in addition to fatty acids and glycerol other components such as; Phosphoric acid, Carbohydrates, Nitrogenous groups& Sulfur. Derived Lipids - They are the compounds that obtained by hydrolytic action for the first two groups. And share some of major characteristic of the former as glycerol, F.A., Mono& Di- glycerides. What are Fats & Oils ?
  6. 6. * C18 Saturated stearic. * C18 mono unsaturated Oleic - 2H * C18 Di-unsaturated Linoleic – 4H Mono glycerides: Have polar (water soluble) – non-polar (water- insoluble) groups : emulsifier "anti staling properties….” What are Fats & Oils ? * Fats = Ester= Acid+ Alcohol.
  7. 7. * Pure triglycerides are colorless, odorless and tasteless. Colors and flavors in the oils& fats are produced by small amounts of impurities that naturally associated with the fats. * All natural lipids contain lypolytic enzymes or lipases that is why all lipids contains some lipids fractions as it is very rare (seldom) to process the fat rapidly enough to prevent the all enzymatic action. What are Fats & Oils ?
  8. 8. The specifications of fats are influenced by:- 1- Weather the fatty acid is the same or dissimilar kinds. 2- Nature of the fatty acid that occupies the middle or B position on glycerol residue. 3- Variation in the degree of saturation& un-saturation of the individual F.A 4- The respective lengths of the fatty acids molecule chain.
  9. 9. "Fatty Acids" - Fatty acids represent 95% of the molecular weight of fats and largely responsible for chemical and physical properties. - Contains even no. of carbon atoms 4-26 and the most common is form 14-22 carbon atoms. - Unsaturated fatty acids are predominate over saturated. - In most of mono unsaturated the double bond is found between Carbon atom 9 and 10 – Counting from Carboxyl group.
  10. 10. - The double bond can reach 7…..but for the most common in vegetable & animal fat is one to three in 18 carbon atom chain length. - Each single bond in saturated fatty acid is completely free to rotate and gives (endows) the chain great flexibility, thus it can exist in a very large number of conformations. - By contrast; each double bond in fatty acids forms a rigid link and is unable to rotate. "Fatty Acids"
  11. 11. - In most of poly unsaturated F.A the double bonds is separated by one methyl's group (CH2)…. Non conjugated while few of them (plant sources) is conjugated (with no separation). - The double bond is the most chemically reactive part of the chain and doesn't represent double strong linkage. - Conjugated ones are more reactive than these in non conjugated position. "Fatty Acids"
  12. 12. - Double bones also more effective in lowering the melting point than the reduction in carbon chain length. - Mono unsaturated fatty acid can exist either in CIS or trans isomers. The trans configuration is more stable so that it usually exhibits higher melting points and less reactivity than CIS one. - In saturated fatty acid the longer chain the higher melting point thus the lowest melting is for butyric acid (4C) and the highest is for cerotic acid (26C) – 8◦c & 87.7◦c respectively. "Fatty Acids"
  13. 13. - Isovaleric acid is the only F.A. that has odd no# of carbon atom (5). -Palmitic acid (16) is the most common F.A. of saturated group as it is found in all known fats& oils and it is the major component in lard and tallow, palm oil, cocoa butter and some other vegetable fats. - The saturated Fatty acids are: Butyri(4), Caproic (6), Caprylic (8), Capric (10), Lauric (12), Myristic (14), Palmitic (16), Stearic (18), Arachidic (20), Behenic (22), Legnoceric (24), Cerotic (26). "Fatty Acids"
  14. 14. - There is no unsaturated F.A. in nature with less than 10 carbon atoms. And from 10 existing in few fat in trace amount. - Oleic is the most widely distributed unsaturated F.A. as it is found in all fats and oil nearly. - Palmitic, Stearic, Oleic, Linoleic are the most common in Edible fats& oils. ------------------------------------------------------------ "Fatty Acids"
  15. 15. *Palm oil: - Is obtained from the meso-carp or outer pulp of the fruit while the inner nut yield palm kernel oil . - It is semi solid 52.5 saturated (palmitic 47.5%) and 47.5% un- saturated (oleic 40%) - Palm kernel oil is 80.8% saturated F.A. with the majority of Lauric 47% and 19.2% un saturated with 18.5% oleic.
  16. 16. Formulations of the most common used palm oil products in Bakeries. BlendTypeSer 24.994 Palm stearin 74.994 Palm oil+ 0.012 TBHQ Palm Oil shortening1- 99.988% Hydrogenated palm oil 47-49 0.012% TBHQ Hydrogenated Palm Oil shortening (HPO 47) 2- 34.0% Palm oil+ 24 Palm stearin 24% Hydrogenated palm oil – 44 All purpose margarine3- 20.488% Palm oil+ 20.50 Hydrogenated palm oil 44 32.80% Palm stearin+ 8.2 liquid Soy bean oil Hard margarine4- 21.0% Palm oil+ 27.0% Hydrogenated palm oil+ 18.0% Palm olein+ 15% liquid soy bean oil Soft margarine5-
  17. 17. Fatty acids composition for most common used palm oil products: Saturated Fatty Acid Sunflower oil Palm Oil Shortening Hydrogenated Palm Oil Shortening (HPO 47) Partially Hydrogenate d Soy Shortening All purpose margarine Hard margarine Soft margarine C 12 0.05 0.23 0.17 0.12 -- -- -- C 14 0.12 0.6 1 0.05 1.44 0.8 0.38 C 16 5.44 43.5 43.3 12.5 41.96 25.8 38.2 C 18 3.95 4.3 24 18 5.77 10.8 20.8 C 20 0.12 0.3 0.44 0.23 -- 0.10 -- Total 9.68 48.93 68.91 30.9 49.17 37.5 59.38 Unsaturated Fatty Acid C 16:1 -- -- -- -- 0.35 0.10 0.15 C 18:1 35.2 37.5 29.5 65.1 38.45 35.8 30.1 C 18:2 55 10 0.57 3.7 11.66 20.5 6.0 C 18:3 0.12 0.3 0.05 0.3 0.36 0.3 0.48 Total 90.32 47.8 30.12 69.1 50.82 56.7 36.73
  18. 18. Stability of different fatty matters measured by rancimat compared to palm oil products: Fatty Matter type Sunflower oil Palm Oil Shortening Hydrogenated Palm Oil Shortening (HPO 47) Partially hydrogenated Soy Shortening All purpose margarine Hard margarine Soft margarine Induction Period 3.05 17.90 43.23 44.96 11.29 14.64 12.37 Temperature : 120o C Air Flow : 20 L/hr 0 5 10 15 20 25 30 35 40 45 Induction Period Sunflower Oil Palm Oil Shortening Hydrogenated Palm Oil Shortening (HPO 47) Partially Hydrogenated Soy Shortening All purpose margarine Hard margarine Soft margarine Stability of different studied fatty matters measured by rancimat :
  19. 19. Physical requirements of Bakery Fats 1-Flavor: Pleasant, clean, free of rancidity. 2-Plasticity: is a combination of crystalline and liquid fats under three essential conditions. a)Solid and liquid phases must be existed together. b) Solid phase must be in a sufficient fine dispersion for the mass to be held together and retain the liquid phase. c) Two phases must be in proper proportion to each other. * The firmness of plastic fat or shortening is influenced by – temperature- particles size- shape of crystalline- solid liquid ratio.
  20. 20. 3- Stability: keeping quality of fats and oils is a measure of their resistance to oxidation and rancidity. The most two commonly used tests for measuring keeping quality are: * The most effective way to evaluate the stability of fats in baked or fried goods is to run actual long term shelf test. Simulating the various conditions normally encountered. Schaal oven test 60◦c incubation till rancid odour) No# of Days till reaching certain peroxide value Active Oxygen Method AOM a steady air stream bubbled through the fat (93◦c) No# of hours till reaching certain peroxide value Physical requirements of Bakery Fats
  21. 21. 1-Tenderizing Effect: Lubricating the structure of baked products by being dispersed in films & globules in dough or batter during mixing, preventing the starch & protein components from forming 3-dimensional gluten network. Are used in baking primarily for Tenderness and Shortness of the baked goods.
  22. 22. 2-Shortening Effect: Is measured by determining the breaking strength of standard wafers (shortometer) and it is affected by the plasticity of fat. Thus the softer fats are rated as superior in shortening value to the harder ones while, the liquid oil has very little shortening ability as they dispersed in globules rather than in film in dough. 3-Aerating Function: The incorporation of air during creaming is solely a function of the shortening. As the fat entraps the air in minute cells and bubbles.
  23. 23. The dry ingredients are dissolved in liquid are: While fat is dispersed through the batter: In the form of films, or clumps which create larger fat surface. 3-Aerating Function:
  24. 24.  Surfactants increase the fat dispersion by increasing the number of fat particles and decrease their individual size, but if the emulsifiers increased more than 8 - 9 % from the fat it will affect inversely on cake volume as excessive of fat dispersion took place.  The fat enclosed air cells/ bubbles forming nuclei for accumulation water vapor and CO2. That increase the volume of butter as a result of its expansions.  Water vapor can’t exert a leavening action without pre- existing air bubbles that incorporated by fat during mixing and act as nuclei in which water vapor and CO2 can accumulate and expand. 3-Aerating Function:
  25. 25. 4- Creaming Function: - It is the ability of fat to absorb air during mixing (% of air incorporated by shortening on basis of its volume). - The creaming quality of fats governs its suitability as cake shortening. - The cake that depending only on the leavening agent to get good volume without using good creaming quality fat normally characterized by coarse grains and large pockets.
  26. 26. -It can be determined by mixing definite amounts and proportions of shortening and granulated sugar, then the density of the mix is measured at intervals .The % of air can be easily calculated based on the resulted densities. - A good shortening incorporated 270% of air at the ratio of 2 parts of shortening and 3 parts of granulated sugar by weight. - Eggs usually added when the air content reached 100- 150% and then it will rise to 300-375%. 4- Creaming Function:
  27. 27. - The finished batter usually contained 275-350% of air based on the volume of shortening as flour and milk cause some air loss while their addition. - For satisfactory creaming quality fats require the presence of highly saturated glycerides. - Partial hydrogenation effectively improves the creaming quality of oils and soft fats. 4- Creaming Function:
  28. 28. 5-Stabilizing Function: - It is intimately related to their aerating function and it is the ability of fats to provide the cake batter sufficient strength to prevent the collapse during baking. - Cake butter is an emulsion in which fat forms the internal or discontinuous phase and the remaining ingredients form the external or continuous phase……in absence of proper aeration this emulsion become very thin and sloppy Week batter structure Collapse.
  29. 29. - The finer the cellular structure of batter the greater will be its mechanical strength. - The plastic shortening doesn't coalesce in a batter as would liquid oil, it nevertheless does accumulate into larger agglomerates that greatly reduce the effectiveness of emulsion. - The higher the liquid and sugar contents of a batter the more difficult to maintain the emulsion in highly dispersed state. (sugar & milk recommended to not exceed more than 40% of total ingredients). 5-Stabilizing Function:
  30. 30. 6- Eating and keeping qualities: a) Eating quality: - Taste, flavor, tenderness, moistness of baked products are decisive factors that govern the acceptance or rejection of product by the consumer. - Fats and oils contribute to eating quality by imparting shortness and tenderness to the baked goods. From other side they enhance the taste of the products resulting in using sugar, eggs and milk.
  31. 31. b) Keeping quality: - It is measured by the degree to which the product retain its freshness over a period of time. - It differs from one product to other based on the ingredients used and method of production but generally using relatively large proportion of fat reduce the rate of staling or at least reduce the changes that normally associated with staling like moisture loss, loss of tenderness and flavor. 6- Eating and keeping qualities:
  32. 32. 1. Adding liquid (soft) oils, hard shortening and margarine to the dough of bakery products affects all the rheological properties clearly and the most affected properties are water absorption, mixing time, stability, weakening, extensibility and resistance to extension. The effect rate was strongly depended on the fat adding ratio. 2. The bread volume was enhanced by using 5-10% fatty matters maximum then decreased gradually by raising the fat or oil ratio..
  33. 33. 3. The type of fatty matter (chemical and physical properties) and the ratio of application affect the organoleptic characteristics of crunchy toast. The range of 12.5-17.5% record acceptable results while 15% was the best fat adding ratio. 4. Not only the fat type affects the stability of that fat in bakery product but the fat adding ratio also greatly impacts the stability of the used fat and shelf life of the bakery products (crunchy toast) where the higher fat ratio the shorter shelf life
  34. 34. 5. The heat treatment used in roasting process of crunchy toast obviously influences the stability of fat and shelf life of finished product as long heat treatment time deteriorates the fat stability and product shelf life more than the higher temperature. 6. Considerable improvement in product shelf life was proved by adding 1.5% (flour basis) of different herbs namely; Cumin, Fennel and Blackseed with all fat types and different heat treatments.
  35. 35. THANK YOU

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