Uppsats: Mjölkens Förändring Från Ko till Bord
Kategori: -Pluggdagar
I chose milk for this assignment. The ingredient in this product is organic low-pasteurized milk and is supplemented with vitamin D and vitamin A. It has been heated to 72-76 degrees for 15 seconds. The package does not inform us about where the cows have lived, where the cow is milked or how far it is from the cow to the factory. I contacted the governmental company called Svensk Mjölk (translation: Swedish Milk) and Arla (the company which are selling the milk) to get information about nutritional information, pasteurization, their view on “organic” and other processed the milk are going through before packaging. I specifically asked for a list of nutrition in the semi-skimmed milk and nutrition in colostrums (raw milk), and was given a rapport of 139 pages. I created the list at the bottom of the page with nutritional value, semi-skimmed milk vs. colostrums. (The figures are not exact.)
The fact that the milk is organic is a good start regarding this product. This means that no pesticides have been used, only natural fertilizer has been used and the cows have not been subjected to any medication. But if a cow, which gives organic milk, gets sick it is seen by a veterinary which decide if the condition will be treated with medication or if alternative treatments can be used. If it is put on medication, the milk won’t be used during medication and the time before the milk can be used again is longer for cows giving organic milk then non-organic milk (withdrawal-time). No medication is used for preventive purposes.
The first process the milk is treated with is separation, which includes separating the water from the fat. In separation; water soluble vitamins ends up in the water, while fat soluble vitamins are present in the fat/cream substance. Most minerals end up in the water substance. After this process different levels of fat/cream are mixed with the watery part to determine the fat content. Semi-skimmed milk, skimmed milk and milk have different levels of fat and fat soluble vitamins. As you can see in the list below, the fatty acids and vitamins are lower in semi-skimmed milk than in colostrums, except for vitamin D which have been added to the product in the supplementation process (see below).
The next step is homogenization which means that the milk is passed through small holes to break up larger fat droplets into smaller one. This process prevents the product to separate into cream and skimmed milk. This make it easier for the body to digest as the fat droplets are smaller, but it is also easier for the body to absorb without any digestive processes as it easily can pass through the intestine wall into the body. It is not a good thing that food particles can pass the intestine wall as they like. Elson Haas claimed that this is a reason cardiovascular diseases increase in today’s society. Oxidation of the milk does decrease by this process, but the taste is lowered.
The next step is to supplement the milk with vitamin A and D as the fat soluble vitamins are lowered and it has to be supplied by law in Sweden. The vitamin D that Arla is using is produced by illuminating sheep-wool with UV light. I did not get information of how vitamin A was produced only that it was ordered by their supplier. I do not know how natural the process for producing the vitamin is, so I can not inform you of this. But if it is a natural product with a natural process that is great news.
After this, pasteurization is needed to destroy dangerous bacteria, viruses and fungus; unfortunately it is also killing the god bacteria needed for the intestines. Pasteurization is also lowering the water soluble vitamins such as vitamin C, the B vitamins, folic acid and protein content to a small degree.
On Arla’s homepage, it says that the fat in the milk is not affected by pasteurization. But I would not agree fully, we know that heat destroys and also damage mono- and poly unsaturated fatty acids. Unfortunately I do not know if 72-76 degrees for 15 seconds is enough time and heat for destroying it. But if we compare each type of fatty acid we see that polyunsaturated fatty acids are lowered with 100%, while total fat, mono- and saturated fatty acids are all lowered with around 65%. If all the numbers would have the same percentage of decrease I would understand their statement, but why would polyunsaturated fatty acids decrease more than the other types of fatty acids if they are were not affected by heat?! So the heat is one of the reasons the fatty acids are lowered in semi-skimmed milk. But mainly it is due to the how much fat is added after the separation (see above). If you remove around 4,18% substance of fat from one liter of milk and then only add 1,5% to get the right amount of fat content, the fat soluble vitamins and fatty acids are lower. Because the fat that was removed contains the vitamins and fatty acids, so these are therefore lost. The saturated fatty acids are not affected, or damaged, by heat as it is more stable.
The water soluble vitamins, B-vitamins and C, in milk are mostly lost affected by the heat during pasteurization as the vitamins are lost during heat. Vitamin B6 can in some forms be very unstable in other forms the heat does not affect the vitamin. Oxidation can affect the folic acid in milk and light can affect the riboflavin. I am not sure about the actual process of pasteurization and if light and/or oxygen are present at all, but it is affected by oxygen before and after the process and so is unpasteurized milk.
The milk contains all 8 essential amino acids, but must be obtained from the cows diet. And the cows from this particular product obtain its food from natural products which is a natural and great thing.
Minerals are stable to heat, but they can bind to proteins molecules if the protein is altered with. So if the mineral bind to this protein it will not be as available as before. One example is that; according to the label 1 dl contains 120mg calcium, but the truth is that the body only absorbs about 29% of this, due to its inorganic form. One good thing with supplementation of vitamin D is that this vitamin is helping the absorption of calcium in the intestines.
One interesting thing that I could not wrap my head around was the fact that the mineral content was increased. I had to contact Svensk Mjölk again to understand the reason. And it brings us back to the separation process. During the separation most of the minerals are placed in the water substance which is 95, 82% of a liter, after 4, 18% fat has been removed. When 1, 5% of fat is added we have 97, 32% of one liter, which mean 2, 68% more water has to be added. In which more minerals are present, so that is the reason why mineral content are higher in processed milk then in colostrums.
Ämne | Mellanmjölk | Råmjölk | |
Semi- | |||
skimmed | Colostrum | ||
milk | milk | Notes | |
Energy | 200KJ/45 kcal | ||
Total fat g. | 1,5 | 4,18 | |
Saturated | 1 | 2,834 | |
Mono unsaturated | 0,4 | 1,203 | |
Poly unsaturated | 0 | 0,104 | |
Transfatty acids g | 0,137 | ||
Cholesterol mg | 6,1 | 13,6 | |
Carbohydrates g | 4,9 | ||
lactose g | 4,86 | 4,73 | |
Protein g | 3,5 | 3,47 | |
Casein gr | 2,69 | ||
Fat soluble vitamins | |||
Vitamin D ug | 0,45 | 0,0096 | Supplied |
Retinol/Vitamin A ug | 12,9 | 36 | |
Vitamin K ug | 0,439 | 1,224 | |
Water soluble vitamins | |||
Tiamin | 0,05 mg | 49 ug | 1μg=o,oo1mg |
Riboflavin | 0,147 mg | 143 ug | 1mg=1000μg |
Pantothenic acid ug | 490 | 477 | |
Folic acid ug | 14,6 | 14,9 | |
Vitamin C mg | 0,6 | 0,8 | |
Vitamin B12 ug | 0,6 | 0,57 | |
Vitamin B6 | 0,045 mg | 43,3 ug | |
Minerals | Water/Fat part | ||
Potassium mg | 160 | 159 | 100/0 |
Chloride mg | 95 | 93 | 100/0 |
Calcium mg | 120 | 119 | 100/0 |
Phosphor mg | 105 | 101 | 100/0 |
Molybden ug | 4,72 | 4,68 | 97//3 |
Iodine ug | 12 | 11,7 | 100/0 |
Iron mg | 0,02 | 0,02 | 86/14 |