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