Lactose-free milk (the regulatory name is a lactose-free milk processing product ) is a product of the processing of drinking milk in which lactose is hydrolyzed or removed [1] .
The product is intended for people suffering from lactose intolerance . It differs from ordinary milk only in the absence or low content of lactose (for example, according to Russian regulations no more than 0.1 g per 1 liter of ready-to-eat product is allowed). At the same time, manufacturers select technologies that ensure the preservation of the product's taste and other properties of drinking milk.
The production of lactose-free dairy products has been mastered in most countries of Western Europe , Argentina , Australia , Canada , Japan , Malaysia , New Zealand , and the USA [2] .
Content
Manufacturing Technologies
Lactose-free milk production technologies are divided into two categories - traditional and using enzymatic degradation of lactose.
In the traditional way, pasteurized milk mixture of a special composition is fermented with sour-milk sourdough, while the components are selected in such a way as to preserve the milk taste to the maximum.
Enzymatic digestion of lactose involves the commercial production of lactase from Aspergillus niger and Aspergillus oryzae fungi or extraction from the yeast Kluyveromyces fragilis and Kluyveromyces lactis and adding it to milk. The enzyme breaks down up to 98% of lactose in milk. If in a liter of ordinary milk contains about 50 g of lactose , then after adding the enzyme it remains no more than 1 g [3] . This possibility appeared back in the 1970s , when the first commercially available enzymes for hydrolysis of lactose were obtained. The resulting low-lactose milk has a fairly pronounced sweet and creamy taste.
The membrane filtration technology developed by Valio in 2001 allows to obtain a product with a lactose content of less than 0.01% [4] . The main stage of the process is ultrafiltration on the membrane, as a result of which part of the lactose is removed from milk, only then the lactase enzyme is added, which removes lactose residues, while the sweetness of the final product is not so pronounced, since the concentration of lactose at the stage of hydrolysis is already reduced.
Comparative characteristic
| Composition: | Plain milk | Lactose-free milk [5] |
|---|---|---|
| Energy value (kcal) | 46 | 39 |
| Protein (g) | 3.2 | 3.3 |
| Carbohydrates (g) | 4.8 | 3,1 |
| Lactose (g) | 4.8 | 0.01 |
| Fat (g) | 1,5 | 1,5 |
| Calcium (mg) | 120 | 120 |
Notes
- ↑ Technical regulation of the Customs Union “On the safety of milk and dairy products” (TR TS 033/2013)
- ↑ Materials of the international conference. The relevance of developing dairy products with a low content of lactose and methods for their production. Lokotchenko N.S., Anikina E.N. Kemerovo. 2012. (inaccessible link) . Date of treatment August 29, 2014. Archived on May 9, 2016.
- ↑ Sredovarka Website about industrial biotechnology
- ↑ Medical portal
- ↑ The magazine “60 years - not age” A. Zharkikh, Ph.D. of sciences