Lactose-Free Milk

Laone, Benedetta, Noelia

Introduction

• Lactase is an enzyme which is produced to digest milk sugar.• It is found in the pancreatic juice or in the surface of villi.• Lactose intolerant are those people who don’t produce

lactase anymore.• The enzyme lactase is produced in the gut of all human

babies; and little amount as adults or no lactase at all.• These people are advised to drink only lactose free-milk.

Benedetta

• How can Industry provide lactose-free milk for lactose intolerant consumers?

= Producing milk using IMMOBILISED ENZYMES; they permit:

• Enzyme-free product• More stable and long lasting enzyme • Re-use of enzyme preparation• The enzyme is obtained from bacteria purified

and enclosed in capsules

The Process of Making Lactose-Free Milk

• Enzyme Immobolisation:• It is possible to make the process more efficient by immobilising the lactose on a

recoverable surface such as alginate. • • First the Lactase is immobilised in alginate beads.• Next the beads are placed in a container over which milk can be passed.• The milk is collected and re-circulated (pump) to convert any remaining lactose

to glucose and galactose. • The circulation is maintained until all lactose has been converted.• This model of an industrial process allow the lactase to be recovered and re-

used (cheaper).• Efficient conversion of lactose to glucose and galactose.• reduced purification of milk since enzyme is retained and a high % lactose

conversion is achieved.• All these factors reduce cost particularly on the downstream processing and

purification.•