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The effect of concentration of vegeren on clotting times with three different milks, whole milk semi-skimmed milk and skimmed milk.

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Introduction

The effect of concentration of vegeren on clotting times with three different milks, whole milk semi-skimmed milk and skimmed milk. Introduction: This investigation is basically about milk coagulation of different milks. Also it includes why each milk type has potentially different milk clotting times using vegeren and how the concentration of vegeren is going to affect the different milks. Vegeren is a vegetarian substitute for rennet, which is also a milk-clotting agent. There are many differences with different milks such as calcium content and protein content. This investigation requires looking at the fat content because this will decide which milk will coagulate more. In nature, milk is a substance produced by mammals to feed their offspring. Milk contains the essentials to help the young mammal grow and develop in its first months of life. Milk contains water, solids such as fat (lipids), proteins (enzymes, caseins, whey proteins), carbohydrates (lactose) and minerals. Other constituents include vitamins, dissolved gasses and bacteria. Milk provides some compounds, which give initial protection from bacterial disease, until the young mammal can build up its own immunity. When a mammal suckles, the milk drawn from the teat is warm and sweet, and the milk sugar (lactose) provides both encouragement to drink more and will provide energy later when needed. First-milk, also known as colostrum, is a pre-milk fluid secreted directly after birth for up to 72 hours by nearly all mammals. It provides both immune factors and growth factors to the suckling mammal. The immune factors boost and regulate the immune system which protects the offspring mainly from viruses and bacteria, others include allergens, toxins, and yeast. A mother can pass cell-specific antibodies to her offspring through the milk to protect it from certain diseases. The young mammal can then produce memory cells for those antibodies to help protect it from the diseases in the future. Colostrum also helps young mammals to grow by stimulating normal tissue growth and aiding repair. ...read more.

Middle

Pilot Tests: Pilot test will be carried out to test how long I should leave the vegeren in the milk standing. This is necessary because I need a good amount of time to make sure it coagulates. If I released the milk mixture too early there could be little or no coagulation at all. If I released it too late, too much coagulation can occur and all the contents may not be able to be drained. Another pilot test would be to test how much vegeren I need to add to the same amount of milk. This is important because a decent amount of vegeren is needed to coagulate the milk, too little vegeren may cause no coagulation and therefore results would be useless. Too much again would not only over -coagulate the milk, but also would waste a lot of the vegeren, which may be needed for the real experiment. Pilot Method: A pilot test was conducted to investigate how long the mixture should be left for. The test was done on skimmed milk (randomly selected). 2 ml of vegeren was added to 2ml of milk and left for six minutes in a syringe facing down towards the lab table secured by a clamp and a stand. The plunger was then removed after the six minutes and was timed how long it took for the milk to come out. It was then repeated with twelve minutes standing time. The whole procedure was repeated once more but for a 50% diluted solution of vegeren. Another pilot test was done to see how much vegeren could be used. 2ml of vegeren was added to 2ml of milk. It was left for ten minutes and drained and timed. This was again repeated but for a 4ml vegeren solution with 2 ml of milk. Pilot results: Vegeren quantities (ml) Water content (ml) Milk quantities (ml) Mixture left standing for 6 minutes (drained)(s) ...read more.

Conclusion

* Even though the stopwatch was stopped accurately as possible, it still remains as a factor to consider. As it was not 100% accurate it will have some sort of effect on the results which were demonstrated by the odd results. Instead an automated stopwatch which can stop precisely as soon as the syringe is emptied could be used. This would eliminate this problem and would produce more reliable results. * Old apparatus used such as syringes that have just been used may still have had traces of milk or vegeren in it and may alter results in terms of wrong contents in the syringe. This means that milks may have possibly mixed and more vegeren may have been used than anticipated, this may have altered the results and would have given wrong results. Distilled water could have been used to clean the apparatus properly or even better would be to use new syringes every time however this was not possible as there simply wasn't that many apparatus. * Variability with the concentrations of the vegeren could have been increased. The experimental procedure showed only four concentrations used instead possible eight concentrations would be used. But with this the quantities would have to be increased to show a significant difference in the concentrations. This would also increase the reliability of the experiment and would produce a better graph. * If larger quantities of everything were used than the protein content of the milks can be taken in account and could possible produces a different outcome. * Also when removing the plunger from the syringe, it was difficult to synchronise it with the stopwatch. A more easy way of draining such as an automated mechanism and so the milk would be more ideal so synchronising the stopwatch and the release of the milk is easier. All these factors affected the results and could have possibly produced the odd results. It has been described how to overcome these factors if any apparatus was available and infinite time was available. These proposed further added investigations could provide more accurate and reliable results. ...read more.

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