New Technologies Applied to Milk and Dairy Products to Reduce Lactose
Fermented milk products such as yogurt have been shown to be tolerated by lactose- intolerant individuals (Heyman 2006; Lomer et al., 2008). The bacteria in the yogurt partially digest the lactose into glucose and galactose (and the glucose to lactic acid); in addition, yogurt semisolid state slows gastric emptying and gastrointestinal transit, resulting in fewer symptoms of lactose intolerance. Aged cheeses tend to have lower lactose content than other cheeses and, thus, may also be better tolerated. Predigested milk or dairy products with lactase are available in some countries and will often permit a lactose-intolerant individual to be able to take some or all milk products freely (Heyman 2006).
Lactase enzyme replacement is another option, although it changes the taste of the food when mixed with dairy products because glucose and galactose produced by lactose digestion are sweeter than the original sugar. To preserve the taste of milk, Valio launched a lactose-free milk drink that is not sweet but has the fresh taste of ordinary milk. Valio patented the chromatographic separation method to remove lactose (Valio 2011). Another strategy involves probiotics that alter the intestinal flora and may have beneficial effects in irritable bowel syndrome patients that persist even after treatment (Almeida et al., 2012). Finally, although lactase expression is not upregulated by lactose ingestion, tolerance may be induced by repeated lactose dosing due to adaptation of the intestinal flora (Shaukat et al., 2010). Plant-based "milks" and derivatives such as soy milk, rice milk, almond milk, coconut milk, hazelnut milk, oat milk, hemp milk, and peanut milk are inherently lactose-free. In conclusion, dairy products with low-lactose and lactose-free are available and could be a valid alternative to replace dairy-based foods for people with lactose intolerance.