Scientific research is always in evolution. Besides trying to identify bioactive substances naturally present in milk, it focuses more and more attention on bioactive compounds and ingredients to develop new functional dairy products and to adapt them to consumers' needs.
In this chapter, bioactive compounds will be reviewed. Some of them are already used in milk fortifications, while some others look particularly interesting for their healthy properties but their application must still be further studied, both for technology and regulations.
Long-Chain Polyunsaturated Fatty Acids
Long-chain polyunsaturated fatty acids (LC-PUFA) are important compounds. They can be distinguished in omega-3 LC-PUFAs (EPA, eicosapentanoic acid, and DHA, docosahexaenoic acid) and omega-6 LC-PUFAs (AA, arachidonic acid). They play an important role in biological reactions such as the regulation of inflammation and related pathologies (asthma, colon diseases), as well as the prevention from cardiovascular risk and from neurologic disorders (depression). For some of these effects, new studies must be further developed, while for some others, the use of LC-PUFAs is completely clear.
The proper ratio between ю6 and ю3 is 5:1. In Western countries this ratio is 15:1, due to the high use of vegetable oils, which are rich in LA. Hence, it is necessary to increase the absorption of ю3 PUFAs to reduce their deficiency (Simopoulos, 2008; Patterson, 2012). A daily absorption of 250 mg of DHA and EPA helps in reducing the risk of cardiovascular diseases.
Fish oil is a good way to ingest ю3. Since 1988, DSH's ROPUFA® has been sold. It is a purified product, with excellent performances with regard to smell and taste. Some other products are available, either with fish origins or obtained from other types of sources such as algae (Life's® and DSM's ARASCO®, Lonza's DHAid's®), krill, chia seeds (Ingredia's Benexia®), hempseed oil, and linen oil, which is involved in the production of flax milk.
The use of krill oil is particularly interesting since it is an important ю3 source rich of antioxidants such as astaxanthine, vitamin A, and vitamin E (Neptune Biotech's Neptune Krill Oil®, Enzymotec's K-real®, Reckitt Benckiser Healthcare's MegaRed®). A clinical study investigated its anti-inflammatory effect on people having vascular diseases or osteoarthritis (Deutsch, 2007).
In 2015, FDA and EFSA authorized the use of Buglossoides arvensis’s seed refined oil. Ahiflower oil® (Technology Crops International) is rich in stearidonic acid (SDA), which is transformed in EPA and in gamma-linolenic acid (GLA) to obtain the best- combined effect of ю3/ю6 (Lefort, 2015).
Over the last few years, genetic bioengineering applications have started to be used in the search for new LC-PUFA sources (Ruiz- Lope, 2012; Kitessa, 2014).