United States Patent:  6,013,255

Assignee:  Gist-brocades B.V. (NL)

Filed:  November 26, 1997

The present invention describes stable water-in-oil emulsions comprising the following components: water, oil, a labile compound of interest, a stabilizing agent and an emulsifier. The labile compound present in the water phase is stabilized by addition of a stabilizing agent which preferably is a polyol. Specific emulsifiers are described which give rise to stable emulsions in the presence of high amounts of a polyol.

SUMMARY OF THE INVENTION

The present invention discloses stable water-in-oil emulsions. Specifically, the present invention discloses a water-in-oil emulsion characterized in that it comprises the following components: water, oil, a labile compound of interest, a stabilizing agent and an emulsifier.

The water-in-oil emulsions of the present invention comprise a labile compound of interest dissolved in the water phase and stabilized by addition of a stabilizing agent. Preferably, the stabilizing agent is a water activity lowering agent. More preferably, the stabilizing agent is a polyol.

The polyol is added to the water phase of the water-in-oil emulsion in high concentrations, i.e. in amounts of at least 10%, preferably in amounts of 10-70%, more preferably in amounts of 30-70% (w/w).

A preferred composition comprises a water-in-oil emulsion containing a labile compound of interest in the water phase together with a polyol, and wherein the emulsion is stabilized using an emulsifier which is active at high concentrations of the polyol. The emulsifier which is used preferably is a distilled monoglyceride or polyglycerol polyricineolate.

Furthermore, the compound of interest preferably is an enzyme, a vitamin, a colourant or a vaccine.

The presented emulsions are used to protect labile compounds before addition to food, feed, cosmetic or oily compositions.

The water-in-oil emulsions of the present invention are stable for prolonged periods of time. They can be used for the preparation of human or animal food compositions. For instance, the water-in-oil emulsions of the present invention are sprayed on feed or food particles. Preferably, the emulsions are sprayed on feed or food particles after dilution of the emulsion in an oil or fat. In addition, the emulsions of the present invention can be used for the preparation of cosmetic compositions.

Claim 1 of 8 Claims

1. A water-in-oil emulsion that is stable upon storage for at least one month comprising 1) water, oil, an enzyme, a water activity-lowering polyol and an emulsifier, wherein the enzyme is present in the water phase of the emulsion at a concentration of 0.01-30% w/w, and 2) the polyol water activity-lowering agent is present in the water phase at a concentration of at least 30-70% w/w, which is effective to stabilize the enzyme, wherein said oil component is provided at a ratio of oil to water from 5:1 to 1:1; and wherein said emulsifier is active in the presence of said polyol and wherein said oil is animal, vegetable or mineral oil.

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