Novel ice-cream coating fats based on diglycerides comprise at least 30 wt. %, preferably 50-90 wt. %, of diglycerides, which diglycerides have an SU content of 10-25 wt. %, while the total fat composition has a SAFA content of 5-35 wt. % and an N line (unstab.) of N.sub.20 <35 and N.sub.25 <10.

This application is the national phase of International application 
PCT/EP95/01572, filed Apr. 25, 1995 which designated the U.S. 
BACKGROUND OF THE INVENTION 
Ice-cream coating fats known so far are mainly based on triglycerides, in 
particular triglycerides containing medium-chain fatty acid residues, such 
as lauric acid residues. Typical examples of such fats are disclosed in, 
e.g., EP 23,150, U.S. Pat. Nos. 5,017,392, 4,560,563, 4,086,370 and 
3,959,516. However, hydrogenated vegetable non-lauric fats and 
triglycerides high in polyunsaturated fatty acids are also known as 
ice-cream coating fats, e.g. from EP 502,697, EP 246,366, EP 23,151 and 
U.S. Pat. No. 3,333,968. 
Hitherto, no composition has been disclosed that is based on diglycerides 
and is suitable as ice-cream coating fat. 
According to EP 402,090 oil-in-water emulsions are known, in which the fat 
phase comprises 10-99 wt. % of a diglyceride mixture having an increasing 
melting point of at most 20.degree. C., which mixture can also contain 
some monoglycerides, the total glyceride blend having a melting point of 
35.degree. C. or below. These emulsions are suitable as cream alternatives 
and for ice-cream application. For the latter application, however, the 
emulsion is used for the ice-cream mass and not for the coating of the ice 
cream. 
SUMMARY OF THE INVENTION 
We have studied how to develop ice-cream coating fats that have a low SAFA 
content (a maximum of 35 wt. %) and an N-line that renders them suitable 
as ice-cream coating fat and which fat composition would be based on the 
presence of a minimum amount of diglycerides. The above-mentioned study 
resulted in novel fat compositions being found that are suitable for 
ice-cream coatings. These novel fat compositions comprise at least 30 wt. 
%, preferably 50-90 wt. %, of diglycerides, which diglycerides have an SU 
content of 10-25 wt. % (S=saturated fatty acid residue; U=unsaturated 
fatty acid residue), while the fat composition displays a SAFA content of 
5-35 wt. % and an N line (NMR pulse, not stabilized) of N.sub.20 &lt;35, 
preferably 1.0-20, more preferably 1.0-5.0; N.sub.25 &lt;10, preferably &lt;1.0. 
Although known ice-cream coating fats, such as coconut oil or cocoa butter, 
have an N.sub.20 of at least 40, it was found, unexpectedly, that fats 
with a lower N.sub.20 can also be applied as ice-cream coating fats; 
however, the fats should contain enough of the required diglycerides. 
DETAILED DESCRIPTION OF THE INVENTION 
The above-mentioned finding therefore contradicts the general belief that a 
high N.sub.20 is a prerequisite for obtaining high crystallisation rates 
and acceptable drying times. 
In particular, the diglyceride part of our novel fat compositions has a 
U.sub.2 content of 75-90 wt. % and an S.sub.2 content below 5 wt. %. 
In a preferred embodiment of our invention the fats display an N.sub.0 of 
more than 35, in particular N.sub.0 =45-80. It was found that, when 
N.sub.0 &gt;80, the coating became too brittle, while below N.sub.0 =35 the 
coating was too soft. The N.sub.20 controls the oral mouthfeel (waxiness) 
and meltdown of our ice-cream coating compositions. 
As coconut oil and cocoa butter have relatively high N.sub.20 values, 
whereas our fats have low N.sub.20 values, the oral meltdown of our fat 
compositions is much shorter than the meltdown of coconut oil- or cocoa 
butter-based fat compositions. 
Our diglyceride compositions are based on diglycerides derived from fatty 
acid residues with 12-24 C atoms, preferably 16-22 C atoms (for the 
saturated fatty acid residues (s)), and for the unsaturated fatty acid 
residues (U) these acids have at least 16 C atoms, preferably 18 C atoms; 
in particular, U is oleic acid. 
Diglycerides can exist as both the sn-1,2 (sn-2,3) and sn-1,3 isomers. Both 
isomers can be applied in the present invention. In a preferred embodiment 
of our invention, however, products enriched in the sn-1,3 isomer are 
applied. Preferably, a ratio of sn-1,3/sn-1,2 diglyceride isomers &gt;2.5 is 
applied to increase the melting profile of the blend. Diglyceride 
fractions enriched in the sn-1,3 isomer can be prepared by fractionation 
(in solvent or dry); solvent fractionation using hexane is preferred. 
Our novel fat compositions can also contain some triglycerides. Preferred 
compositions also comprise 10-50 wt. % of a vegetable triglyceride 
composition, preferably having a total (U.sub.3 +U.sub.2 S) content of at 
least 50 wt. %. 
Although our triglyceride compositions can be manufactured by blending of 
their components, either as pure components or as mixtures of components, 
a preferred way of producing our fats is by performing a glycerolysis of a 
liquid oil and glycerol. This glycerolysis can be performed by using an 
enzyme, preferably a 1,3-specific enzyme, or by using a base, such as 
sodium methanolate. 
The reaction conditions for an enzymatic conversion of a liquid oil with 
glycerol are typically: 
weight ratio oil: glycerol 1:10 to 100:1; 
reaction times: 6-120 hours; 
temperature: 0-40.degree. C. 
enzymes: selected from Rhizopus, Rhizomucor, Pseudomonas, Candida, and 
preferably Humicola. The enzymes are used in amounts of 100-1000 LU/gm of 
oil. 
The oils that can be applied for the above-mentioned conversion are 
typically: sunflower oil, high-oleic sunflower oil, safflower oil, 
high-oleic safflower oil, corn oil, cottonseed oil, rapeseed oil, olive 
oil and soybean oil. 
After separation from residual glycerol, the crude glycerolysis product is 
processed to produce the final product by evaporation to remove 
monoglycerides and optionally fractionation (dry or solvent). This can 
lead to an optimum ratio of diglycerides to triglycerides in the mixture 
and this post-treatment can be used to control the N values (in all 
instances NMR pulse measurements were performed on non-stabilised fats, 
i.e. after the fats had been stored at 0.degree. C. for 90 minutes) or the 
SAFA content of the product. Sometimes it can be suitable to subject the 
fats as obtained to a refining treatment (using bleaching earth and 
steam). 
A typical ice-cream coating composition comprises the following 
formulation: 
35-55 wt. % of a polysaccharide, preferably sugar; 
25-65 wt. % of the fat composition according to the invention; 
0-20 wt % of cocoa powder, preferably 5-15 wt. %; 
0-10 wt. % of a milk component, preferably skim-milk powder; 
0-2 wt. % of an emulsifier, preferably lecithin. 
Part of our invention are also ice creams coated with the above-mentioned 
ice-cream coating compositions.

EXAMPLE 1 
1.1 Glycerolysis of high-oleic sunflower oil 
High-oleic sunflower oil (having the composition given below) was reacted 
with glycerol in a ratio of 5 parts of HOSF oil to 1 part of glycerol by 
weight, in the presence of Humicola lipase (1000 LU/gm of oil). The 
reaction time was 24 hours and the temperature was 40.degree. C. After 
separation from glycerol, monoglycerides were removed by evaporation at 
240.degree. C. and 1 mbar pressure. The resulting product was fractionated 
in hexane at -10.degree. C.; the product obtained was refined by a 
treatment with bleaching earth and steaming at 190.degree. C. for 4 hours 
to give a diglyceride-rich fraction of the following composition: 
______________________________________ 
C.sub.16:0 
C.sub.18:0 
C.sub.18:1 
C.sub.18:2 
C.sub.20 
% SAFA 
______________________________________ 
Product (= Fat A) 
3.9 5.7 86.2 1.5 2.6 12.2 
HOSF (= Fat B) 
4.0 4.7 84.3 4.9 2.1 10.8 
______________________________________ 
1.2 Preparation of another diglyceride-product (=fat E) 
Two diglyceride-rich fat products (an olein and a stearin) were prepared 
from the glycerolysis of HOSF, followed by separation techniques: 
a) 100:20:0.5 by weight of HOSF, glycerol, Lipolase 100 L enzyme (ex-Nove 
Nordisk) respectively, were stirred at 40.degree. C. for 24 hours. 
b) Excess glycerol was decanted off, and mono-glycerides/FFA were removed 
from the crude reaction product (22.1 wt % DG, 3.8 wt % MG) in a falling 
film evaporator (260.degree. C., 0.3 mm Hg abs.). 
c) After refining, the diglyceride rich product was fractionated from 
hexane (2:1 hexane oil to oil by weight at -12.degree. C.), collecting the 
olein (16.9 wt % DG, yield 90 wt %) and the stearin (63 wt % DG, 7.8 wt % 
MG, yield 10 wt %). 
d) The olein product had a composition of: 16.9 wt % DG, 0.8 wt % MG DG 
part 0.0% SS type, 15.1% SU type, 84.8% UU type. 
e) The diglyceride content of the olein product was increased by a 
two-stage silica treatment: 
i) Diglycerides and monoglycerides were absorbed onto silica, using hexane 
as a solvent (in the proportion 2:1:1 hexane, oil, silica by weight). The 
silica complex was washed with hexane (2.6:1 hexane to oil by weight) and 
the wash discarded. 
ii) The silica complex was washed with 88 wt % hexane/12 wt % acetone 
(3:2:1 wash to oil by weight), and the diglyceride-rich wash collected. A 
diglyceride-rich fat was formed by evaporation of the hexane/acetone 
solvent. 
f) The diglyceride enriched olein had a composition of: 51.5 wt % DG, 0.1 
wt % MG, DG part 0.0% SS type, 16.5 % SU type, 83.5% UU type. 
g) Excess monoglycerides were removed from the stearin product via a silica 
treatment with hexane/acetone (88 wt % hexane, 12 wt % acetone) as the 
solvent (5:1:1.21 solvent, oil, silica by weight) washed with 3 parts 
solvent to 1 part oil (by weight). The stearin product was recovered from 
the wash solvent by evaporation. 
h) The silica treated stearin had a composition of: 69.6 wt % DG, 0.3 wt % 
MG DG part 0.6% SS type, 25.1% SU type, 74.4% UU type. 
A diglyceride-rich fat blend was prepared by blending the silica treated 
stearin and diglyceride enriched olein in the ratio 30:70 by weight. The 
blend was bleached and deodorised. 
The refined blend contained: 55.5 wt DG, 0.1 wt % MG. The DG composition 
was 0.4 % SS, 21.1 % SU, 78.5 % UU. The FAME profile of the total blend 
was (wt %): 
______________________________________ 
14:0 16:0 16:1 18:0 18:1 18:2 18:3 20 22 24 
0.0 4.0 0.1 4.5 84.9 4.6 0.0 0.6 1.1 0.2 
______________________________________ 
giving a total SAFA level of 10.1 wt %. 
The triglyceride part contained 20 wt % of SOO and 65.9 wt % of OOO. 
1.3 The glyceride compositions of the refined fat A, of the starting oil 
(=Fat B), of a chemically made product (Fat C), of coconut oil (Fat D) and 
of the second enzymically made fat (=E) were as follows: 
______________________________________ 
(Wt %) 
Diglyceride 
Fat Triglyceride (1,3 + 1,2) 
Monoglyceride 
______________________________________ 
A 14.2 80.3 5.5 
B 98.0 2.0 -- 
C -- 98 2 
D 98.0 2 -- 
E 44.4 55.5 0.1 
______________________________________ 
The melting profile of the refined fat composition was measured. Fat C is a 
product that is made using a chemical conversion with a base; Fat D is 
coconut oil. 
______________________________________ 
Solids Temperature (.degree.C.) 
Fat 0 20 25 
______________________________________ 
A 42.0 2.7 0.1 
B 4.1 
C 63.5 18.8 10.7 
D 89.0 37.6 0 
E 34.4 0.2 0 
______________________________________ 
2. Ice-cream coatings 
2.1 Ice-cream coatings were prepared, using the following recipe: 
______________________________________ 
Recipe: wt. % 
______________________________________ 
sugar 42.7 
fat 38.1 
cocoa powder D-11-MC 12.5 
SMP 6.2 
lecithin 0.5 
______________________________________ 
The fats applied were: cocoa butter (=CB), coconut oil (CN) and the refined 
enzymic conversion product of Example 1.1 and 1.2. 
2.2 Ice creams were dipped in a melt of the above-mentioned ice-cream 
coating compositions. 
The following results were obtained: 
______________________________________ 
wt. % 
Coating T Dripping time 
Drying time 
of 
Fat (.degree.C.) 
(sec) (sec) coating 
______________________________________ 
CB 40.5 17 122 36 
Enz. conv. 
41.0 25 99 26 
product A 
CN 38.5 22 73 36 
Enz. conv. 
40 23 97 32 
product E 
______________________________________ 
The oral properties of the products were similar (all good-tasting). 
However the products according to the invention resulted in coatings that 
were softer and less brittle, which had quicker and smoother meltdown than 
CB-based coatings.