Dairy alternatives are generally derived from plant based ingredients such as soya, rice, almond, oat, coconut, hazelnut or hemp. While they are sometimes used as a replacement for cow’s milk, they are not nutritionally equivalent. The main difference is that the dairy alternatives are often fortified with calcium and vitamin B12, while dairy milk is a natural source of calcium and a rich matrix of other micronutrients (including riboflavin, vitamin B12, iodine, potassium and phosphorus). Dairy milk is naturally higher in good quality protein at about 3.5 %. The alternatives are generally around 0.5 % protein, with the exception of soya at around 3 %. Some alternatives have added sugar, while milk contains lactose, a natural sugar. Soy milk is the best source of protein of the non-dairy options. It does not naturally contain calcium and vitamin B12, but is often fortified with these nutrients. Rice milk is much lower in protein and could be fortified with calcium, and vitamins D and B12. Oat milk is naturally sweet and more palatable non-dairy milk options. Often sugar is added and this beverage contains very little protein (less than 1 gram per glass). Almond milk is made out of ground almonds with water. This non-dairy drink is very low in protein with just 1 g per glass, but may have more calcium than dairy milk, along with vitamins D and E. Hemp milk is made of hemp seeds, which are high in heart-healthy omega-3 fatty acids. It also has some protein but falls short in calcium. Coconut milk has little protein and about the same saturated fat as whole milk — about 4 grams in a cup.
Flavoured milk is a pasteurised and homogenised low fat dairy milk product that is coloured, sweetened and flavoured. It then undergoes a sterilisation process which removes all microorganisms and helps to extend its shelf life. This product can be kept on shelf for longer than regular dairy beverages.
Fermented milk products, also referred to as cultured milk products, are milk products that have been treated with bacterial cultures (usually lactic acid bacteria), yeast or mould. The purpose of the fermentation is to convert lactose (the naturally occurring milk sugar) to lactic acid. This causes gelatinisation, which thicken the milk. Examples of fermented milk products include yogurt, kefir, maas, sour cream and crème fraîche. These products may have additional health effects. This may be related to the lower pH (acidity), which affects the rate at which the stomach is emptied and thereby reducing the glycaemic response (i.e. the effect on blood sugar). Alternatively the beneficial effects may be due to bio-active peptides present in fermented dairy. These substances have been linked to improvement of cardiovascular symptoms (e.g. high blood pressure) and of low-grade inflammation (evident in obesity).
Functional foods are an emerging food category, generally regarded as foods that may provide additional health benefits following the addition/concentration of a beneficial ingredient, or the removal/substitution of a harmful ingredient. Dairy foods such as milk, yogurts and spreads are often used as carriers for functional ingredients. An example of a dairy-based functional food is a yogurt drink with added plant sterols or stanols, which have been clinically proven to lower cholesterol. For any health claims to be made on functional food products it is necessary that they are approved by South African Department of Agriculture, Forestry, and Fisheries (DAFF) regulations
Agriculture accounts for the majority of methane gas emissions in Ireland (85%) due to the dominance of cattle and sheep livestock production in Irish agriculture. These ruminant animals release methane as a bi-product of digestion of food in the rumen and large intestine. This process, called enteric fermentation, produces more than half of all greenhouse gas emissions from agriculture. Methane emissions from livestock depend on a number of factors, in particular livestock type, diet quality and feed intake. Research into the utilisation of this methane for energy production and the reduction of methane emissions by the dairy sector is ongoing.
The temperature and duration applied in pasteurisation (usually 72°C for 15 seconds) is relatively low in that it is sufficient to destroy micro-organisms without significant destruction of the nutritional properties. The important nutrients in milk are not affected by heat. Pasteurized milk is an excellent source of calcium, protein, riboflavin, vitamin A, and phosphorus. It is a good source of thiamine and vitamin B12.