Methods for making improved texture cereal bars
A method of producing a cereal bar is provided in which the cereal comprises a cereal mixture including ready-to-eat (RTE) cereal pieces joined together with a binder, where the cereal and binder together form a cereal matrix which is heated for a time and temperature to reduce the water activity of the external portion thereof while maintaining an internal portion of the cereal matrix at a higher second water activity. The method provides cereal bars requiring less compressive force to be formed into a cohesive self-supporting structure in providing a chewy reduced-density cereal bar with improved shelf life.
1. A method for making cereal bars, comprising:
forming a cereal matrix comprising cereal pieces and an edible binder in a wt:wt ratio of about 2:1 to about 1:2, respectively, into a cereal matrix layer by application of a compressive pressure force that does not exceed about 50 psi to form the cereal matrix layer having intact cereal pieces and to achieve a density of about 0.05 g/cc to about 0.5 g/cc and a thickness of about 0.5 cm to about 5 cm with an exposed external portion and an internal central portion, wherein the exposed external portion and the internal central portion each has an initial water activity exceeding about 0.35;
heating the cereal matrix layer for a time and temperature in an indirect fired oven having a heated zone and a subsequent non-heated zone wherein the cereal matrix layer dwells in each of the heated zone and the subsequent non-heated zone for at least about 2.5 minutes effective so that the water activity is less than about 0.3 in the exposed external portion of the cereal matrix layer, while maintaining the internal central portion of the cereal matrix layer at a water activity greater than about 0.40, to provide a heated layer;
cooling the heated layer to provide a cooled layer; and
cutting the cooled layer, or alternatively the cereal matrix layer prior to the heating step, effective to form discrete cereal bars.
2. The method of claim 1 , wherein the initial water activity of the cereal matrix layer is from about 0.50 to about 0.60, and a final water activity of the layer is about 0.40 to about 0.55 after the cooled layer is allowed to equilibrate for up to about 3 months at ambient temperature conditions.
3. The method of claim 1 , wherein the heating of the cereal matrix layer is conducted at a temperature of about 200 degrees F. to about 450 degrees F., as measured in oven air space at a location approximately one inch from the external portion of the layer, for a time of about 1 to about 20 minutes.
4. The method of claim 1 , wherein the forming shapes the cereal matrix layer into a preselected cross-sectional bar shape.
5. The method of claim 1 , wherein the cutting is performed on the cooled layer.
6. The method of claim 1 , wherein the forming comprises sheeting.
7. The method of claim 1 , wherein the forming comprises extruding the cereal matrix in generally rectangular cross-sectional shape.
8. The method of claim 1 , wherein the binder is heated to a temperature of about 120 degrees F. to about 230 degrees F. before the mixing with the cereal pieces.
9. The method of claim 1 , wherein the binder comprises a carbohydrate syrup composition.
10. The method of claim 1 , wherein the cereal bar contains 0 to 10 wt % sugar alcohols.
11. The method of claim 1 , wherein the cereal matrix contains cereal pieces and the edible binder in a wt:wt ratio of about 1.5:0.5 to about 0.5:1.5, respectively.
12. The method of claim 1 , wherein the cereal bar further includes 0.1 to about 10 wt % dairy solids.
13. The method of claim 1 , wherein the cereal pieces are selected from the group consisting of rolled cereals, puffed grains, toasted flakes, extruded pieces and mixtures thereof.
14. The method of claim 13 , wherein the cereal pieces comprise a combination of at least two different types thereof.
15. The method of claim 1 , wherein the cereal bar comprises a sweet bar.
16. The method of claim 1 , wherein the cereal bar comprises a savory bar.
17. A method for making cereal bars, comprising:
sheeting a cereal matrix comprising cereal pieces and carbohydrate syrup in a wt:wt ratio of about 1.5:0.5 to about 0.5:1.5, respectively, to provide a cereal matrix layer by application of a compressive pressure force that does not exceed about 50 psi to achieve a density of about 0.05 g/cc to about 0.5 g/cc at a thickness of about 0.5 cm to about 5 cm with an exposed external portion and an internal central portion covered by the exposed external portion, wherein the exposed external portion and internal central portion each has an initial water activity exceeding about 0.35;
heating the cereal matrix layer for a time and temperature in an indirect fired oven comprising a heated zone and a subsequent non-heated zone wherein the cereal matrix layer dwells in each of the heated zone and the subsequent non-heated zone for at least about 2.5 minutes effective so that the water activity is less than about 0.3 in the exposed external portion of the cereal matrix layer, while maintaining the internal central portion of the cereal matrix layer at a water activity greater than 0.35, to provide a heated layer;
cooling the heated layer by exposing the heated layer to chilled air effective to immobilize the binder to provide a cooled layer; and
cutting the cooled layer effective to form discrete cereal bars.
18. The method of claim 1 , wherein a temperature of the internal central portion is limited to about 150° F. to about 290° F. during the heating step.
19. The method of claim 17 , wherein a temperature of the internal central portion is limited to about 150° F. to about 290° F. during the heating step.