This invention relates to a method for preparing sweet bakery fillings using enzymatically modified xyloglucan.

5 Bakery fillings inserted into breads, dumplings and other food products have been known to leak out of the food product when heated. JP2002349576 discloses the use of enzymatically modified xyloglucan in savory fillings, e.g., Chinese bean-jam. However, this reference does not address the problems in processing sweet fillings having a high sugar content.

o Statement of the Invention

The present invention is directed to a method for making a baked food containing a sweet filling; said method comprising incorporating into a sweet filling formulation comprising at least 15 wt% sugars and from 0.1 to 2 wt% enzymatically modified xyloglucan.

5 The present invention is further directed to a composition which is a sweet bakery filling formulation comprising at least 15 wt% sugars and from 0.1 to 2 wt% enzymatically modified xyloglucan.

Detailed Description of the Invention

Unless specified otherwise, all percentages are weight percentages (wt%), all

0 temperatures are in °C and all operations are performed at room temperature (20-25 °C).

Weight percentages are based on the entire weight of the dough formulation unless otherwise specified. The "filling formulation" is the mixture of ingredients which forms the filling. The composition of the filling formulation is substantially identical to that of the filling, although the filling may contain slightly less water due to evaporation during

5 cooking. The term "sugars" refers to mono- and di-saccharides in any natural sweeteners, e.g., sucrose, corn syrup, honey, maple syrup, brown rice syrup, molasses and agave. The weight of sugars is the dry weight of saccharides contained in the natural sweetener.

Preferably, the filling formulation is heated to produce the final filling, preferably over medium heat. Preferably, the filling is encased in pastry dough to produce a filled raw o pastry. Filling may be refrigerated or frozen prior to use. Preferably, the filled raw pastry is baked under suitable conditions known to those skilled in the art. In general, baking temperatures may range from 300 to 550 °F (150 to 290 °C), and times may be from 5 to 60 minutes. The filling formulation preferably comprises at least 18 wt% sugars, preferably at least 20 wt%, preferably at least 22 wt%; preferably no more than 60 wt%, preferably no more than 55 wt%, preferably no more than 50 wt%, preferably no more than 45 wt%, preferably no more than 40 wt%. Preferably, weight percentages of sugars are total weight 5 percentages of sucrose, fructose and glucose.

Preferably, enzymatically modified xyloglucan is made from xyloglucan which has Mw from 500,000 to 1,500,000, preferably from 700,000 to 1,300,000. Preferably, the modified xyloglucan is present in the filling formulation in an amount of at least 0.15 wt%, preferably at least 0.2 wt%, preferably at least 0.3 wt%, preferably at least 0.4 wt%;

i o preferably no more than 1.7 wt%, preferably no more than 1.5 wt%, preferably no more than 1.3 wt%, preferably no more than 1.1 wt%, preferably no more than 0.9 wt%.

Enzymatic modification is believed to remove side-chain galactose units from the basic hemicellulose backbone of xyloglucan. A preferred enzyme is β-galactosidase. Preferably, the enzymatic modification produces gelling xyloglucan, i.e., xyloglucan which is a gel in

15 the range from 30-70°C. Preferably, the gelling temperature is no higher than 65°C,

preferably no higher than 60°C, preferably no higher than 55 °C, preferably no higher than 50°C. Times for enzymatic modification depend on other parameters but can easily be determined. Typical reaction times may vary from 4 hours to up to 2 days, providing enzymatically modified xyloglucan with different gelling temperatures ranging from 30-

20 70 °C. The upper limit is not critical, but beyond it there is little change in gelling

temperature and it would not be economically feasible to continue the reaction beyond this point. Preferably, from 30 to 60% of the galactose units are removed, preferably at least 33%, preferably at least 35%; preferably no more than 55%, preferably no more than 50%, preferably no more than 45%.

25 Preferably, the filling formulation comprises from 40 to 85 wt% water; preferably at least 45 wt%, preferably at least 50 wt%, preferably at least 55 wt%; preferably no more than 80 wt%, preferably no more than 75 wt%, preferably no more than 70 wt%. The amount of water includes water present in liquid ingredients, e.g., fruit juice, liquid sweeteners (e.g., honey, corn syrup), milk and vinegar

30 Examples of other optional ingredients in filling formulation are as follows: gums, including xanthan gum and guar gum; gelatin; eggs, such as egg white; egg replacers; salt; yeast; chemical leavening agents, including baking powder and baking soda; fats, including margarine, butter and oils (e.g., vegetable oil); vinegar; dairy products, including milk, powdered milk, and yogurt; soy milk; nut ingredients, including almond meal, nut milk, and nut meats; fruit and vegetable ingredients, including fruit puree and fruit concentrate; and flavorings, including vanilla, cocoa powder, and cinnamon. However, this is not a comprehensive list of all ingredients that can be used to make sweet fillings. Preferably, the total amount of optional ingredients (excluding any contained water) is no more than 25 wt%, preferably no more than 20 wt%, preferably no more than 15 wt%; preferably at least 5 wt%, preferably at least 10 wt%, preferably at least 12 wt%. Preferably, the composition comprises from 1 to 9 wt% fats; preferably at least 2 wt%, preferably at least 2.5 wt%; preferably no more than 7 wt%, preferably no more than 6.5 wt%.

The composition of the present invention is useful for bakery products having a sweet filling, such as pies, cakes, pastries, donuts, muffins and turnovers. The composition of the present invention can be processed to the bakery product in a conventional manner, for example by producing a dough or a batter which is used to encase the sweet filling and optionally baking it, depending on the kind of food product to be produced.

Preferably, the xyloglucan comprises less than 0.5 wt% organic solvents, preferably less than 0.2 wt%, preferably less than 0.1 wt%. Preferably, the xyloglucan comprises less than 1 wt% chitosan, preferably less than 0.5 wt%, preferably less than 0.2 wt%, preferably less than 0.1 wt%. Preferably, the xyloglucan comprises less than 1 wt% pectin, preferably less than 0.5 wt%, preferably less than 0.2 wt%, preferably less than 0.1 wt%.

Examples

Enzymatic modification process: lmg/ml of β-galactosidase is added into 3% of xyloglucan (in PBS buffer, pH 5.5), the reaction is conducted in oven (55-60 °C) for 7.5 hours. Then the enzymatically modified xyloglucan is freeze-dried, the resultant material has a gelling temperature of 37 °C (measured by rheometer, at G'=G", G': storage modulus; G" : loss modulus)

The intention of doing enzymatic modification is to obtain a thermal gelling xyloglucan. Untreated xyloglucan has a non-gelling property that G' (storage modulus) and G" (loss modulus) decrease at the same time as temperature increases. After 7.5h enzymatic reaction, enzymatically modified (EM) xyloglucan exhibits a distinctive rheology profile compared to that of untreated xyloglucan. G' starts to increase at 30 °C and cross G" at 37 °C. The intersection of G' and G" is generally believed to be the gelling point so that 2% EM-xyloglucan has a gelling temperature at 37 °C. The rheology profile of 2 % METHOCEL K4M shows that it has a gelling temperature above 70 °C. The modules of untreated xyloglucan and EM-xyloglucan are comparable to those of METHOCEL K4M, which are in the magnitude of 10s Pa or above. The rheology data suggests the enzymatic treatment gives xyloglucan a thermal gelling property.

GPC data suggests that untreated xyloglucan has a molar mass about 100,000 Da. NMR was used to quantitatively measure the galactose remove ratio (GRR) after reaction. The signature peaks from 105 ppm to 98 ppm represent galactose, glucose and xylose content respectively in xyloglucan. Assuming the peak area of glucose is 1, in the conventional sample, the ratio of galactose over glucose is 0.49 to 1. β-galactosidase is specifically cleaving galactose from back bone, so the glucose content is assumed not to change during this reaction. The ratio of galactose over glucose is 0.31 to 1, which leads to 37 % galactose removal for the measured EM-xyloglucan.

Lemon Danish and Donut Filling

The lemon juice was approximately 80-90 wt% water.

Procedure:

1. In a cooking vessel, dry blend sugar, starch and METHOCEL HPMC, and blend until homogeneous.

2. In a separate container, mix water, vinegar and juice. Add flavor

3. Blend water mixture with the dry ingredients in the cooking vessel. Mix unit sugar is dissolved.

4. Place mixture over medium heat. Mix in egg yolk. Continue mixing until homogeneous.

5. While stirring constantly, cook filling until it is thick and smooth, without boiling.

6. Remove from heat and stir in butter.

7. Store refrigerated or frozen.

Testing in Pie Crust:

8. Cut crust dough into 4-inch (10.2 cm) diameter circles.

9. Weigh 18 g of filling onto center of dough, fold dough over and crimp edges.

10. Freeze overnight.

11. Bake at 475 °F (246 °C) on middle oven rack for 11-12 minutes.

12. Remove from oven for evaluation. Starch, native xyloglucan and gelling EM-xyloglucan were compared to

METHOCEL K100M in lemon filling application. Starch and xyloglucan were not able to hold the ingredient during oven heating (400 °F (204 °C), 15 min). In comparison, gelling EM-xyloglucan and METHOCEL K100M hold the ingredient inside of the pocket. The surface of the EM-xyloglucan pastry has cracks which are slightly smaller than those on the K100M pastry, although both are within acceptable limits.