Methods for making purple corn nectar that contains native anthocyanins originating from the source purple corn kernels and methods for using the same are provided.
Where is ample need and demand for foods containing antioxidants such as anthocyanins. Oftentimes, these antioxidants are added to products such as juices, candy and other consumables. The public is however increasingly becoming suspicious of compounds that are not native to the source material of the consumables and are instead added during the process. Furthermore current regulations are requiring manufacturers to disclose more about the composition of the products sold to the public and to label their products in such a way as to reflect any added materials. To respond to the consumer's demand, many manufacturers are starting to emphasize the preservation of certain compounds during the process of making a given consumable rather than adding them later. For instance, certain proteins and vitamins that are usually eliminated during the manufacturing process are now preserved to give extra value to the consumable. However, with the attempt to preserve these compounds come new manufacturing challenges. Oftentimes, some of these challenges relate to the fact that some of the compounds that one is trying to preserve degrade during the processing of the desired product. Furthermore, other non-desirable solids tend to get extracted during the process.
Corn nectars or syrups and the processes to make them are known in the art. U.S. Pat. No. 2,822,303 describes a method for making corn starting from a starch. There is a need however for a corn nectar that contains native anthocyanins (originating from the kernels used in the process itself) and manufacturing methods for making it.
The current invention aims, among other things, to provide such methods for the manufacture of a purple corn nectar containing anthocyanins, native to the very kernels used in the manufacturing of the nectar, in amounts that exceed those in known corn nectar manufacturing methods while minimizing the extraction of other solids that can interfere with the nectar making process.
Generally, in some of its embodiments, the invention aims to provide methods that result in a purple corn nectar composition having an antioxidant profile high in native anthocyanins resulting directly from the kernels used in process of making the nectar. In other embodiment, the invention provides brewing compositions containing a certain amount of the said purple corn nectar as well as confectioneries containing the purple corn nectar. More particularly, the invention relates to a corn nectar having high anthocyanin content as well as consumables made from the invention and its dried products thereof.
Objects and advantages of the invention are set forth in part in the ensuing description, or may be obvious from the description, or may be learned through practicing the invention. Suitable methods and compositions are described herein without limitations on the scope of the invention.
In this application the words nectar and syrup are equivalent and maybe used interchangeably. The word “grits” is used to mean corn kernels ground to a particle size which could be as fine as a flour or meal or as coarse as several hundred microns. For simplicity when the grits are larger than 600 microns they will be called grits and when they are smaller than 600 microns they will be called flour or meal. The words candy bar, nutritional bar or health bar are intended to mean the same product.
In one of its embodiments, the invention describes a first method for obtaining a purple corn nectar having total solids in excess of sixty percent by weight and having an anthocyanin content in excess of 80 milligrams per one hundred grams of nectar from purple corn grits. The grits were chosen such that the majority of them had a size larger than 1200 microns. For instance in one of the examples the purple corn grits were chosen such that more than 50% of the grits had a size larger than 1200 microns, larger than 1200 microns but smaller than 3350 microns, preferably larger than 1200 microns but smaller than 1680 microns, more particularly, 65% to 70% of them were larger than 1500 microns but less than 3500 microns. A first acid hydrolysis was carried out on the grits by steeping them in water that has been acidified by the addition of enough sulphuric acid to reach a pH below 7 and more particularly below 6 but preferably below 5. As described in example 1, the acid hydrolyzed grits were then subjected to the action of the two saccharifying enzymes San Extra and Saczyme. A filtrate was obtained that had about 1.89% solids (table 8 in the examples section). When concentrated to about 70% solids as shown in table 9 (Nectar 1), the nectar obtained showed an anthocyanin content of about 86 milligrams per 100 grams of nectar.
In another embodiment of the invention, purple corn grits were chosen such that more than 50% of the grits had a size larger than 1200 microns, larger than 1200 microns but smaller than 3350 microns, preferably larger than 1200 microns but smaller than 1680 microns, more particularly, 65% to 70% of them were larger than 1500 microns but less than 3500 microns. A first acid hydrolysis was carried out on the grits by steeping them in water that has been acidified by the addition of enough sulphuric acid to reach a pH below 7 and more particularly below 6 but preferably below 5. As described in example 2 and tables 8 and 9, the acid hydrolyzed grits were then subjected to the action of the two saccharifying enzymes Alpha-Amylase and Saczyme. After the action of these two enzymes, the hydrolyzed product maybe further subjected to isomerizing enzymes if for instance, high fructose nectars are desired. In example 2, a filtrate was obtained that had about 1.88% solids (table 8 in the examples section). When concentrated to about 65% solids, as shown in table 9 (nectar 2), the nectar obtained showed an anthocyanin content of about of 84 milligrams per 100 grams of nectar.
Comparatively, when corn meals/flours, having particles sizes much less than 600 microns as shown in table 5 and described in comparative examples 3 and 4, are used to make the nectars, the purple corn nectars obtained, (nectars 3 and 4 in table 9), while slightly higher in total carbohydrates than the ones obtained from the larger size grits they show significantly lower concentrations of anthocyanins only 43 to 74 mg per 100 g of nectar as compared to 84 to 86 mg per 100 g of nectars from the grits (table 9). A close inspection of table 8 demonstrates that the smaller size of the corn meal particles enables extraction of far more solids which is shown from these results to be a detrimental factor to the extraction of higher amounts of total anthocyanins. While not intending to be bound by any theories, the investigators recognized that a certain size of grits when hydrolyzed in the presence of acids and treated with saccharifying enzymes, of the type described in the invention, produce nectars higher in total anthocyanins than purple corn meals (flours) with particle sizes much below 600 microns. It can be appreciated from table 10 that grits having a size predominantly between 1200 microns and 33350 microns show an average anthocyanin contents at least 60% higher than their counterparts with sizes much below 600 microns. On skilled in the art could for instance use the larger size grits to obtain nectars that are much higher in anthocyanins but only slightly lower in total carbohydrates.
The purple corn nectar of the invention is useful in many applications and in particular consumable compositions. The purple corn nectar of the current invention finds uses as a sweetener, thickener, binder, natural colorant and a source of antioxidants. These consumable compositions may contain various amounts of the purple corn nectar of the invention as a liquid or a dried form. Ranges vary from a few milligrams to several hundred grains in the total consumable composition depending on the application.
For instance in one of the embodiments of the invention, the purple corn nectar is used as a substrate for alcoholic fermentation for a beer. Example 7 describes a process of making a purple beer using the purple corn nectar of the invention as a suitable substrate for alcoholic fermentation. In this example for instance hops were replaced by purple corn kernels.
The purple corn nectar of the invention not only provides the source of sugar for the yeast but also an antioxidant source both for nutritional value and protection of the beer against the oxidative effects of oxygen. Furthermore, the purple corn nectar of the invention serves as a colorant for the beverage. In some other embodiment of the invention the purple corn nectar of the invention is used as an additive to the fermentation of other fruits or grains. One skilled in the art can easily determine from the description of this invention suitable proportions of the nectar for each intended application.
In other embodiments of the invention such as drinks, the purple corn nectar of the invention is used as not only as a suitable sweetener but also as a colorant and antioxidant. The juices of this embodiment can be natural juices such as orange and other fruit juices as well as artificial juices and lemonades as described in example 9. One skilled in the art may choose to dry the purple corn nectar of the invention and use the dried resulting product in any of the embodiments discussed above. One may also supplement the resulting dried product with other nutritional or non-nutritional compounds.
In another embodiment of this invention and in particular in the nutritional (snack bar) bar, health snacks and candy manufacturing industry, a binder is often required to hold the different components together thus acting like a glue. The corn nectar of the invention lends itself to such application. Furthermore, the purple corn nectar of the invention is not only capable of contributing by its mechanical utility but also by its added nutritional value of delivering sufficient amounts of antioxidant to the candy bar or health and nutritional bar.
In some aspect of the current invention, the purple corn nectar of the invention is used to provide the natural safe color desired for the application. Example 6 describes one of the embodiments of the invention whereby a composition for making a snack bar comprises as one of its elements the purple corn nectar of the invention. Alternatively, example 5 describes an embodiment of the invention teaching the application of the invention to the manufacturing of a hard candy consumable.
The following examples are presented to further illustrate and explain the present invention and should not be taken as limiting the scope of the invention in any regard.
A modified version of the method described in “Characterization and measurement of anthocyanins by UV-Visible spectroscopy” by M. Monica Giusti and Ronald Wrolstad, Current Protocols in Food Analytical Chemistry (2001) F1.2.1-F1.2.13, Copyright © 2001, John Wiley & Sons, Inc. was used to determine the content of anthocyanins in the different nectars, using the THERMO SCIENTIFIC™ Evolution Spectrop[hotometer.
E551 Buffer Preparation (wear personal protective equipment):
Monomeric anthocyanin (mg/L)=(A*MW*DF*1000)/(ε*1)
A=absorbance (absorbance reading at peak wavelength)
MW=molecular weight (449.2 for cyanidin-3-glucoside)
DF=dilution factor
ε=molar absorptivity (26900)
Method for Determination of % of Solids in the Samples before and after Concentration
Weigh and record the weight of an aluminum pan, add 5 mL of material, record weight, place to dry at 65° C./18-24 hrs then weigh again. Run sample in duplicates. Calculate average % solids based on the moisture weight loss.
The grits and corn meal extractions were all run in duplicates and values for all measurements were averaged and reported as average values.
Concentrated sulphuric acid (Sold by Sigma Aldrich)
Suntava purple corn grits product code 220102, lot #3273NM06 (supplied by Suntava, Inc.)
1920 g of water contained in a stainless steel container is brought to a temperature between 55 and 60° C. To this, 330 g of corn grits are added. Next approximately 0.035 g of concentrated sulphuric acid is added to achieve a starting pH of 5.35. The container with its content is then loosely covered with a lid and placed at 60° C. in an oven overnight (about 20hrs). The next day, the container with its content is removed from the 60° C. and 5 ml of San Extra is added to the content. The content is then stirred and allowed to cool to 35° C. At this point the content is filtered through a colander lined with a fine mesh cheese cloth. 5 ml of Saczyme is then added to the now filtered content and mixed well. The filtered content is then brought to 60° C. on an electric burner top to activate the enzymes. It is then placed at 60° C. in an oven for 30 min. After this, the whole filtered content is brought to a boil and held there for 1 minute to stop the enzymatic activity. It is then left to simmer at medium-low for 15 minutes. The filtered content is then further filtered through a bag filter (nominal size of one micron) using a vacuum filtration apparatus known in the art. At this point the final pH, the concentration of anthocyanins as well as the weight of the filtrate recovered are determined. The recovered filtrate is then placed to dry overnight at 60° C. in an air air oven.
Concentrated sulphuric acid (Sold by Sigma Aldrich)
Suntava purple corn grits product code 220102, lot #3273NM06 (supplied by Suntava, Inc.)
1920 g of water contained in a stainless steel container is brought to a temperature between 55 and 60° C. To this, 330 g of corn grits are added. Next approximately 0.035 g of concentrated sulphuric acid is added to achieve a starting pH of 5.35. The container with its content is then loosely covered with a lid and placed at 60° C. in an oven overnight (about 20 hrs). The next day the container with its content is removed from the 60° C. and 5 g of Alpha-Amylase is added to the content. The content is then stirred and allowed to cool to 35° C. At this point the content is filtered through a colander lined with a fine mesh or cheese cloth. 5 ml of Saczyme is then added to the now filtered content and mixed well. The filtered content is then brought to 60° C. on an electric burner top to activate the enzymes. It is then placed at 60° C. in an oven for 30 min. After this, the whole filtered content is brought to a boil and held there for 1 minute to stop the enzymatic activity. It is then left to simmer at medium-low for 15 minutes. The filtered content is then further filtered through a bag filter (nominal size of one micron) using a vacuum filtration apparatus known in the art. At this point, the pH, the % solids and the % filtrate recovered are determined. The recovered filtrate is then placed to dry overnight at 60° C. in an air oven.
Concentrated sulphuric acid (Sold by Sigma Aldrich)
Suntava purple corn meal product code 220106, lot #113099 (supplied by Suntava, Inc.)
1920 g of water contained in a stainless steel container is brought to a temperature between 55 and 60° C. To this, 330 g of corn meal/flour are added. Next approximately 0.035 g of concentrated sulphuric acid is added to achieve a starting pH of 5.75. The container with its content is then loosely covered with a lid and placed at 60° C. in an oven overnight (about 20 hrs). The next day the container with its content is removed from the 60° C. oven and 5 ml of San Extra is added to the content. The content is then stirred and allowed to cool to 35° C. At this point the content is filtered through a colander lined with a fine mesh or cheese cloth. 5 ml of Saczyme is then added to the now filtered content and mixed well. The filtered content is then brought to 60° C. on an electric burner top to activate the enzymes. It is then placed at 60° C. in an oven for 30 min. After this, the whole filtered content is brought to a boil and held there for 1 minute to stop the enzymatic activity. It is then left to simmer at medium-low for 15 minutes. The filtered content is then further filtered through a bag filter (nominal size of one micron) using a vacuum filtration apparatus known in the art. At this point, the pH, the % solids and the % filtrate recovered are determined. The recovered filtrate is then placed to dry overnight at 60° C. in an air oven.
Concentrated sulphuric acid (Sold by Sigma Aldrich)
Suntava purple corn meal product code 220106, lot # 113099 (supplied by Suntava, Inc.)
1920 g of water contained in a stainless steel container is brought to a temperature between 55 and 60° C. To this, 330 g of corn meal/flour are added. Next approximately 0.035 g of concentrated sulphuric acid is added to achieve a starting pH of 5.75. The container with its content is then loosely covered with a lid and placed at 60° C. in an oven overnight (about 20 hrs). The next day, the container with its content is removed from 60° C. and 5 g of Alpha-Amylase is added to the content. The content is then stirred and allowed to cool to 35° C. At this point, the content is filtered through a colander lined with a fine mesh or cheese cloth. 5 ml of Saczyme is then added to the now filtered content and mixed well. The filtered content is then brought to 60° C. on an electric burner top to activate the enzymes. It is then placed at 60° C. in an oven for 30 min. After this, the whole filtered content is brought to a boil and held there for 1 minute to stop the enzymatic activity. It is then left to simmer at medium-low for 15 minutes. The filtered content is then further filtered through a bag filter (nominal size of one micron) using a vacuum filtration apparatus known in the art. At this point, the pH, the % solids and the % filtrate recovered are determined. The recovered filtrate is then placed to dry overnight at 60° C. in an air oven.
White sugar—197 g
1 cut pitted dates
¼ cup of Suntava purple corn nectar
¼ cup of creamy nut butter
1 cup roasted nuts (almonds or peanuts)
1½ cup of rolled oats
Fermentis Safale Us-05 Dry Ale Yeast obtained from Fermentis
Optimal yeast Temperature range: 15-24 C (59-75 F)
Wine Yeast Lalvin RC-1118 Saccharomyces cerevisiae—champagne obtained from Lallemand.
Dosage: 5 g makes 1-6 gallons
1 cup fresh lemon juice
3 to 4 cups cold water (depending on desired strength)
½-1 cup Purple Corn Nectar (or to taste)
Combine fresh lemon juice, Purple Corn nectar and water. Mix well until nectar has completely dissolved. Add more Purple Corn nectar depending on desired sweetness. Refrigerate.
This application is a divisional application which claims benefit, under 35 U.S.C. §121, to U.S. patent application Ser. No. 14/321,702 filed on Jul. 1, 2014, now pending, which in turn claims benefit to U.S. Patent Provisional Application No. 61/843,132 filed on Jul. 5, 2013 the disclosure of which is herein incorporated by reference in its entirety.