Production of Lactose-Free Milk



PRODUCTION OF LACTOSE-FREE MILK

Do you feel discomfort after consuming milk or dairy products? As it turns out, people all around the world have this problem called lactose intolerance. Lomer et. al. (2007) asserts that 70% of the world population have lactase non-persistence (loss of enzyme activity) that cause discomfort. The severity of the condition varies among people and are still studied.

Lactose is found in breast milk and a good energy source for infants. As the baby grows -and as it stops consuming milk- need for the enzyme that digests lactose is unnecessary and its production stops (Jelen & Tossavainen, 2003). This is normal for other species of mammals, but humans continue consuming milk from various animal sources (cow milk, goat milk, sheep milk etc.) yet experience lactose intolerance.

The dairy industry is a big one. In 2019, it had an estimated 673.8 billion U.S. dollars of market value, and market share of liquid milk was 54% (Shahbandeh,2020). Milk is the product that lactose-intolerant people react most.

A problem faced by the industry is lactose intolerance because it cost them consumers. The dairy industry is losing many people experiencing lactose intolerance. So, lactose-free milk is introduced.

 

Lactose-free milk is not necessarily completely lactose-free. A distinction can be made to call such products low lactose or lactose-free. A common lactose-free milk from your supermarket contains 0.1% lactose.  Such low concentrations generally do not cause discomfort.

Lactose is hydrolyzed using many technologies. Lactase enzyme is used as an essential part of the process. This could be done in a tank where lactase is introduced to pasteurized milk or a continuous operation where the enzyme is chemically bonded to alginate beads (immobilized enzyme). This technology allows reuse and the stability of enzyme (Mai et. al, 2013). The lactose content of milk can be reduced using a packed bed of alginate beads. A 2010 patent uses a combination of filtration technologies to produce lactose-free milk where lactose content is reduced by many steps of filtrations and a final enzyme process. The paper reports a lactose content below 0.01% (“Lactose-free milk product”,2010).

Additionally, after hydrolysis of lactose, milk becomes sweeter since end products (glucose and galactose) are sweeter than lactose. This gives the milk a pleasant taste and reduces the need for sweeteners.

Industrial need for the enzyme has led to biotechnological applications of enzyme production. Today, the industrial lactase enzyme is produced using microbes, especially fungi. Microbes can grow in bioreactors and produced enzymes are collected and purified.

 

REFERENCES

Jelen, P., & Tossavainen, O. (2003). Low lactose and lactose-free milk and dairy products - prospects, technologies and applications. Australian Journal of Dairy Technology, 58(2), 161st ser.

LOMER, M. C. E., et al. (2007). “Review Article: Lactose Intolerance in Clinical Practice - Myths and Realities.” Alimentary Pharmacology & Therapeutics, vol. 27, no. 2, 2007, pp. 93–103. Crossref, doi:10.1111/j.1365-2036.2007.03557.x.

Mai, T., Tran, V., & Le, V. (2013, March 14). Biochemical studies on the immobilized lactase in the combined alginate–carboxymethyl cellulose gel. Retrieved October 23, 2020, from https://www.sciencedirect.com/science/article/pii/S1369703X13000636?casa_token=dya_1Rv7TeYAAAAA%3AWN0E11iLuFIQL0vvRTz5jIQFxP49M96s-GXRHJZdRbLVvAGm-6xtYGj16Ai0iKp9 CO V dEs9bA

Shahbandeh, M. (2020, September 03). Dairy products: Production by category worldwide 2019. Retrieved October 21, 2020, from https://www.statista.com/statistics/869510/global-dairy-production-by-category/

US8449938B2 - Lactose-free milk product and processes for producing the same. (2010, November 09). Retrieved October 23, 2020, from https://patents.google.com/patent/US8449938B2/en