A method for producing a lactase-containing composition which is purified by selectively removing protease contaminating the lactase using simple and easy means; a lactase-containing composition; and a dairy product containing the lactase-containing composition. A method for producing a lactase-containing composition having a reduced protease content includes: dissolving a composition containing lactase and protease in an aqueous salt solution having an electric conductivity of from 2 to 45 mS/cm; bringing the resultant solution into contact with an ion exchange resin; and collecting a fraction which is not adsorbed onto the ion exchange resin.

The present invention relates to a method for producing a dairy product using an enzyme having lactase activity.

A method of generating a saccharide, especially lactulose or lactosucrose, in the presence of a transgalactosylase enzyme, is described herein.

The invention relates to a process for producing a lactose-free milk powder with a fat-standardized content, such as whole milk, skim milk, lowfat milk, organic milk, non-organic milk and the like.

The invention provides a gas infused milk product, wherein the gas infused milk product comprises a lactose hydrolyzed concentrated milk infused with a soluble gas. The invention also provides methods of making such a product. Such methods include providing milk (skim milk, 1% milk, 2% milk, whole milk, half and half, cream or other milk product) and concentrating and hydrolyzing the milk with lactase to from a lactose hydrolyzed milk concentrate. The milk can be concentrated in vacuo (in a vacuum) in order to remove the dissolved gasses from the lactose hydrolyzed milk concentrate. Soluble gasses, such as nitrous oxide or carbon dioxide are then introduced into the lactose hydrolyzed milk concentrate to form a gas infused milk concentrate. In one aspect of this invention, the gas infused milk concentrate is then introduced into a stream of carbonated or still water resulting in a gas infused milk beverage.

To provide a method that reduces clogging of a filter device (filter) during a filtering step prior to addition of milk to a previously formulated lactase solution, and to provide a lactase solution which is not prone to having an occurrence of clogging of the filter device. A lactase solution having a permeation rate of 5 kg/min×m.sup.2 or more at the time of permeation of 366 kg/m.sup.2 through a membrane filter with a pore diameter of 0.22 μm at a concentration for having an activity of 1,000 NLU/g or 2,000 ALU/g, after being subjected to a stirring treatment at 100 rpm, 10° C. for 16 hours with a concentration for having an activity of 5,000 NLU/g or 10,000 ALU/g.

The subject invention aims to solve the problem of production of glucose accompanying the production of galactooligosaccharides after milk raw material is treated with lactase, by additionally adding transglucosidase to convert glucose to functional isomalto-oligosaccharide. The subject invention relates to a process for the production of a milk product enhanced with oligo-saccharides, characterized in that lactase and transglucosidase are used to treat milk raw materials. The subject invention further relates to the milk product of the process of the invention, whose oligo-saccharide content reaches a functional level. Human physiological effect assays confirm that the milk product increases intestinal probiotics, reduces harmful intestinal bacteria, improves the intestinal bacterial flora, reduces blood total cholesterol, reduces blood LDL cholesterol, increases blood HDL cholesterol, and improves the immunity, and may be used as low glycemic index (GI) dietary supplements.

The present invention relates to new improved methods for expressing native lactases in their native hosts. Methods for homologous as well as heterologous expression of lactase in lactic acid bacteria with altered expression dynamics are comprised by present invention.

Systems and methods for filtering dairy may filter milk with a wide-pore filter to produce a wide-pore retentate and a wide-pore permeate, wherein the wide-pore retentate may comprise casein and beta-lactoglobulin. The systems and methods may further ultra-filter the wide-pore permeate to produce an ultra-filtered retentate and an ultra-filtered permeate, wherein the ultra-filtered retentate comprises alpha-lactalbumin. The systems and methods may further nano-filter the ultra-filtered permeate to produce a nano-filtered retentate and a nano-filtered permeate, wherein the nano-filtered retentate comprises lactose. The systems and methods may further perform reverse osmosis (RO) on the nano-filtered permeate to produce a reverse osmosis retentate and a reverse osmosis permeate.

A process for preparing lactose-free skimmed, partially skimmed and whole milk is proposed in which: (1) the milk is pasteurized and skimmed; (2) the skimmed milk is hydrolyzed enzymatically by a lactase; (3) the hydrolyzed skimmed milk is microfiltrated to obtain an ultrafiltration retentate (RMF) and a microfiltration permeate (PMF); (4) the PMF is ultrafiltrated and an ultrafiltration retentate (RUF) and an ultrafiltration permeate (PUF) are obtained, 5) the PUF is nanofiltrated and a first nanofiltration retentate (RNF1) and a first nanofiltration permeate (PNF1) are obtained, 6) the PNF1 is nanofiltrated to obtain a second nanofiltration retentate (RNF2) and a second nanofiltration permeate (PNF2), and 7) final step: lactose-free milk is obtained by mixing one or more of the fractions deriving from one or more of the previous steps.