Compare and contrast the physicochemical events in the production of butter and margarine INTRODUCTION Butter is one of the diary products, that is a energy-yielding food products which are produced from the milk of mammals such as sheep, goats, buffalos and yaks. Twenty litres of whole milk is required in the production of one kilogram of butter. It is produced from the cream of milk with a fat content of about 80%. Chemically butter consists of butterfat, milk proteins, water and vitamins A, D and E. Colour of butter is generally pale yellow but it range from deep yellow to light white. It has a pH ranging from slightly acidic to neutral making it compatible with other food products (Bethany Moncel).
Part B) Prepare a report on the following aspects of the food processing- -Raw materials -quality, specifications -characteristics and types of equipment used -Production systems used in processing e.g. small scale or large, manual, automation, computerisation -Food safety -Work safety Raw materials –quality, specifications Milk: Whole milk produces a better quality of milk due to its thickness, and therefore it is normally used. Goat, cow or sheep milk is usually used; each gives the cheese a unique flavour and texture. Approximately 16 cups of milk are needed to make 2.5kg of cheese. Starter culture: About 6 tablespoons should be used to make 2.5kg of cheese.
American consumers also love the rich flavor of Greek yogurt which is also creamier and sourer than regular yogurt. Regular yogurt is fermented milk produced by bacterial fermentation, which produced lactic acid. Lactic Acid acts on milk protein and produces the creamy yogurt texture and sour flavor. Like many yogurts Greek yogurt is made with milk that has been enriched by boiling off some of the water and adding extra butterfat and powdered milk. The milk for the yogurt is heated to 80 °C (176 °F) to kill off bad bacteria and to prevent milk curding.
The corn flour and water solution will then be thickened. Chemical Reaction when making Tofu Basically, there are two chemical reactions take place when tofu pudding is being made, include protein denaturation and coagulation. The denaturation occurs when soy milk is being heated. The proteins in soy milk are denatured and when the denatured proteins meet the gypsum powder mixture, coagulation slowly proceed. The gypsum powder in the mixture reacts with water to form solid gypsum slowly.
The method involved precipitation by saturation with magnesium sulfate and it was concluded that mature bovine milk had nitrogen distributed as follows: 78.3 % casein, 9.1 % albumin, 3.5 % globulin, 4.1 % protease peptone and 5 % non protein. The αs1-, αs2-, β-, and κ-casein are the major casein proteins. Apart from dairy products like cheese and yogurt, isolated casein is used in a variety of non-dairy foods like beverages, dessert-types, bakery, pasta, confectionery and meat products, pharmaceutical and health care products (Mulvihill and Ennis, 2003). It was observed by Warner (1944), that casein could be precipitated from alkaline solution by acidification. Caseins exist in milk as polydisperse, almost spherical particles, called casein micelles.
Estimation of Fat in Milk Aim: To determine the fat content in milk. Principle: The milk is mixed with H2SO4 and iso-amyl alcohol in a special Gerber tube, permitting dissolution of the protein and release of fat. The tubes are centrifuged and the fat raising into the calibrated part of the tube is measured as a percentage of the fat content of the milk sample. The method is suitable as a routine or screening test. It is an empirical method and reproducible results can be obtained if procedure is followed correctly.
Apart from milk and cultures yogurt are also made with various ingredients including sweeteners, fruits, stabilizers and flavors (Tamime and Robinson, 1999). There are various kinds of yogurt based on chemical and physical nature, flavor and production style. The chemical nature of the yogurt
“Fat molecules clump together when bonding with triglycerides, which bond to other triglycerides” (Dlc.dcccd.edu: Lipids). Most fats are in the form of triglycerides (which contain a triple bond), which clump together to form clumps of fat when agitated (as seen in shaking heavy cream). “Fat molecules also play a major role because they bond to solidify in heavy cream to leave a product of skim milk; which is milk in which fat is completely removed from the liquid into a solid form” (Lower, Claire: Cream Science: On Whipping, Butter, and Beyond). If this type of lipid did not play this role, fat molecules would not solidify and separate from its liquid
The most abundant proteins in milk are water-soluble protein molecules referred to as caseins, the caseins may be precipitated out of the milk by reaching their respective isoelectric point via a change in pH via the addition of an acid, this experiment used acetic acid to lower the pH to approximately 4.6. Butterfat is also precipitated by this change in pH. The resulting solution is precipitated casein and butterfat within a watery solution referred to as whey, the whey contains water soluble proteins that do not precipit... ... middle of paper ... ...cium tests confirmed the presence of phosphate and calcium, respectively, within the liquid whey filtrate, this was as expected, as the metal ions are water-soluble. The positive Biuret’s Protein Test confirmed that the solid curds contains proteins, this is as expected as the curds should consist primarily of insoluble casein proteins. The butterfats when added to water were found to be non-miscible, indicating that the substance is a non-polar hydrophobic material, this confirms that the butterfats consist of the non-polar fat molecules.
Refined sugars are not only found in the form of small, white crystals used in baking sweets. They are not only found as added sugars to such items as pasta sauce and deli meat. As I mentioned earlier, sugars are carbohydrates and come in all forms, including wheat flour, which is used to make such foods as breads, muffins, pizza dough, pasta and crackers. Consider trading in these “white” starches for whole-wheat starches, which don’t increase our blood sugar levels nearly as much. Many pastas and crackers today are made with brown rice, and you can hardly tell a difference in taste.