WO2010094837A2

WO2010094837A2 - Sugar product

Info

Publication number: WO2010094837A2
Application number: PCT/FI2010/050103
Authority: WO
Inventors: Kyllikki Kilpi; Reijo Suomela
Original assignee: Nordic Sugar Oy
Priority date: 2009-02-17
Filing date: 2010-02-17
Publication date: 2010-08-26
Also published as: WO2010094837A3; FI20095144A0

Abstract

The present invention relates to a product that contains sucrose and a berry polyphe- nolic compound. The present invention also relates to a use of a polyphenolic compound for controlling postprandial blood glucoseand/or insulinconcentration in a subject. The present invention further relates to a use of the product for controlling postprandial blood glucoseand/or insulinconcentration in a subject. In addition, the invention relates to a method of controlling postprandial blood glucoseand/or insulinconcentration in a subject by administering a polyphenolic compound and/ or the product to the subject.

Description

SUGAR PRODUCT

FIELD OF THE INVENTION

[0001] The present invention relates to a sugar product and a method of producing the product. Particularly, the present invention relates to a product that contains sucrose and a polyphenol. The present invention also relates to a use of a polyphenol for controlling postprandial blood glucose and/or insulin concentration in a subject. The present invention further relates to a use of the sugar product for controlling postprandial blood glucose and/or insulin concentration in a subject. In addition, the invention relates to a method of controlling postprandial blood glucose and/or insulin concentration in a subject by administering a polyphenol and/or the sugar product to the subject.

BACKGROUND OF THE INVENTION

[0002] Sugar, also called as sucrose and saccharose, is a disaccharide consisting of glucose and fructose. Sugar is a natural product, and its pure, sweet taste is the standard for all sweeteners. Sucrose occurs naturally in fruits, berries, vegetables and root crops, but in modern-day food most of it comes from added sugar, i.e. purified (refined) sugar from sugar beets or sugar cane. Sugar's main function is to provide sweetness and energy, but it also has a number of other functional properties. It can be used for purposes such as flavour enhancement, preservation, providing body and texture, and freezing point reduction. Areas of application range from confectionery, ice-cream and pastries to beverages and fermentation. The most common industrial sugar products are granulated sugar, liquid sugar, syrup, icing sugar, nib sugar and brown sugar.

[0003] It is known that sugar in jam, marmalade and juice impedes bacteria growth and keeps the colour and flavour of the berries.

[0004] Health issues with respect to sucrose intake have increased and high intake of sucrose is considered to have an influence on obesity, insulin resistance, diabetes and cardiovascular disease.

[0005] Wilson T. et al., (J Med Food 11 (1 ) 2008, 46-54) did not find a significant effect of cranberry juice on postprandial glucose concentration compared to its isocalohc sugar solution.

[0006] The present invention provides a novel sugar product and a novel manner for controlling postprandial blood glucose and/or insulin concentration in context with the consumption of added sugar in a subject. BRIEF DESCRIPTION OF THE INVENTION

[0007] The present invention relates to a sugar product that contains sucrose and at least one berry polyphenol. The present invention also relates to a method of producing the sugar product. The present invention further relates to a use of the product for controlling postprandial blood glucose and/or insulin concentration in a subject. In addition, the present invention relates to a use of a berry polyphenol for controlling postprandial blood glucose and/or insulin concentration in a subject. In addition, the invention relates to a method of controlling postprandial blood glucose and/or insulin concentration in a subject by administering a berry polyphenol and/or the sugar product to the subject.

[0008] The objects of the invention are achieved by the sugar product, methods and uses set forth in the independent claims. Preferred embodiments of the invention are described in the dependent claims.

[0009] Other objects, details and advantages of the present invention will become apparent from the following detailed description and examples.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 shows plasma glucose concentrations after ingestion of the berry puree meal and the control meal in study subjects as presented in Example 3.

[0011] Figure 2 shows venous plasma glucose concentrations after ingestion of the berry puree meal and the control meal in study subjects as presented in Example 4.

[0012] Figure 3 shows serum insulin concentrations after ingestion of the berry puree meal and the control meal in study subjects as presented in Example 4.

DETAILED DESCRIPTION OF THE INVENTION

[0013] High carbohydrate diets increase generally postprandial glucose levels in blood and are considered to increase the risk of obesity, insulin resistance, type 2 diabetes and cardiovascular disease (CVD).

[0014] In the present invention, sugar refers to sucrose, a disacchahde of glucose and fructose. Further, the term "added sugar" refers to purified and/or refined sucrose derived from sugar beets or sugar cane that is added to an edible product or consumed separately with an edible product, for example, sprinkled on an edible product. In one embodiment of the present invention, sugar and/or the added sugar are derived from sugar beets.

[0015] In general, a polyphenol refers to a chemical compound found in plants and characterized by the presence of more than one phenol unit per molecule. Fruits, berries, vegetables as well as tea, especially green tea, chocolate/coca, coffee, walnuts an peanuts contain varying amounts of polyphenols, which can be extracted from these sources using generally known techniques. Polyphenols and polyphenol extracts derived from different plants, such as green tea and berries, are commercially available. Particularly in the present invention, the term "a berry polyphenol" refers to a polyphenol and/or mixture of polyphenols derived and/or derivable from a berry, such as, a strawberry, a raspberry, a blackberry, a blueberry (bilberry), a lingonberry, a cranberry, a red- and/or blackcurrant or any mixture thereof. The berry polyphenol may be in the form of a polyphenol extract, a berry extract, a berry concentrate or puree, a berry juice concentrate, a dried berry, a dried crushed berry, dried berry powder and/or a mixture thereof.

[0016] In the present invention, the term "a dried berry" refers to a dried whole berry or dried chopped or sliced berry, and the term "a berry extract" refers to an extract that is enriched with one or more ingredient or component of the berry, such as a polyphenol.

[0017] The term "a berry concentrate" or "a berry puree" refers to an essentially homogenous puree, that is optionally concentrated, i.e., the content of water, predominantly, is controlled.

[0018] In the present invention, the term "sugar product" refers to an edible food ingredient and/or a semifinished product that contains added sugar at least 50 weight-% based on the total weight of the sugar product. Typically, the amount of added sugar is from 55 to 99 weight-% based on the total weight of the sugar product. In one embodiment of the invention, the amount of sugar is from 75 to 95 weight-% based on the total weight of the sugar product. Typically, the sugar product of the present invention is not to be eaten as such and/or alone, but with other foods.

[0019] The sugar product of the present invention has a water content of max 20 weight-% based on the total weight of the sugar product. The water content of the sugar product of the present invention is typically from 5 to 15 weight-% based on the total weight of the sugar product. [0020] The sugar product of the present invention may also contain additional ingredients and/or additives typical for this type of products. Examples of such components are thickening agents, such as alginate or pectin, anticaking agents, preservatives, colors, flavors, dietary fibers, organic acids and other sugars, such as fructose.

[0021] The sugar product is well suited to be used, for example, with fresh or frozen berries and/or fruits and with or without heating or cooking. Especially when the sugar product contains a thickening agent, such as alginate, and citric acid, it can advantageously be used with frozen berries to make jam or puree without heating.

[0022] The sugar product of the invention may be in the form of a granulated sugar type of product or a soft brown sugar type of product, for example.

[0023] In one aspect, the present invention is based on the surprising finding that berries and/or the berry polyphenols are capable to attenuate glucose and/or insulin response of sucrose in a subject. It is thus, an object of the present invention to develop a sugar product containing at least one berry polyphenol and sucrose. In one embodiment of the invention, the amount of sugar is about 75% based on the total weight of the product, and in another embodiment of the invention, the amount of sugar is from 75 to 95 weight-% based on the total weight of the sugar product.

[0024] The berry polyphenol may be in the form of a polyphenol extract or a berry extract, a berry concentrate or puree, a berry juice concentrate, a dried berry, a dried crushed berry, dried berry powder and/or a mixture thereof.

[0025] In one embodiment of the invention, the sugar product is formulated into a granulated sugar type of product, wherein the sucrose is in the form of granulated sugar and the form of the polyphenol is a dried berry, a dried crushed berry, a berry powder and/or a mixture thereof. In this embodiment, the product is produced using any method for dry mixing applicable to food industry. In another embodiment of the invention, the product is formulated into a soft brown sugar type of product, wherein the sucrose is in the form of granulated sugar and the form of the polyphenol is a polyphenol extract or a berry extract, a berry concentrate or a berry puree, a berry juice concentrate or a mixture thereof. In this embodiment, the product is produced using any method for wet mixing applicable to food industry. [0026] In general, soft brown sugar is produced by coating the granulated sugar with a dark sugar syrup. In the present invention, the soft brown sugar type product is produced respectively by coating the granulated sugar with a berry juice concentrate. In a preferred embodiment, the soft brown sugar type product is produced by first mixing the granulated sugar with berry powder, extract or another type of dried berry preparation and then coating the obtained mixture with a berry juice concentrate.

[0027] The sugar product of the present invention can be cooked and/or boiled. In one embodiment of the invention, the sugar product is uncooked and/or unboiled product.

[0028] In another aspect, the present invention is based on a finding that when sucrose is consumed with berries the blood glucose and/or insulin level of a subject increases less than when the same amount of sucrose is eaten without berries. It is thus an object of the present invention to provide a method for controlling and/or lowering the postprandial blood glucose and/or insulin concentration by administering and/or ingesting a berry polyphenol and sucrose essentially simultaneously.

[0029] Further, another object of the present invention is to provide the sugar product for use in reducing and/or lowering the postprandial blood glucose and/or insulin concentration. Additionally, the present invention relates to a use of a berry polyphenol for the manufacture of a product for reducing and/or lowering the postprandial blood glucose and/or insulin concentration in context with the consumption of added sugar in a subject i.e., when the polyphenol and sucrose are ingested essentially simultaneously. Furthermore, the present invention relates to the berry polyphenol for use in reducing and/or lowering the postprandial blood glucose and/or insulin concentration in context with the consumption of added sugar in a subject, i.e., when the polyphenol and sucrose are ingested essentially simultaneously.

[0030] The product of the present invention comprises sucrose and at least one berry polyphenol. The berry polyphenol may be in the form of a polyphenol extract or a berry extract or concentrate, a berry juice concentrate, dried crushed berries, dried whole berries and/or dried berry powder. The polyphenol extract, the berry extract or concentrate and the berry juice concentrate are produced using any feasible method of extraction and/or concentration applicable to food industry. The dried crushed berries, the dried whole berries and the dried berry powder are produced using any feasible method for drying and/or grinding applicable to food industry.

[0031] Berries are good sources of various polyphenols in the diet. The largest and most studied polyphenols are flavonoids, which include fla- vonols, anthocyanins, catechins and flavanols. Flavonols, anthocyanins and flavanols (catechins) are three subclasses of flavonoids found in berries. Chlorogenic acid is a typical phenolic acid and ellagitannins and proanthocya- nidins are typical tannins found in berries. Anthocyanins are pigments and provide pink, red, blue or purple color to red fruits, such as cherries, strawberries, raspberries, blackberries, blueberries, red and black currants.

[0032] The amounts of polyphenols in different berries vary. For example, the content of polyphenols is about 85 mg/100 g in blueberries, about 27 mg/100 g in raspberries, about 24 mg/100 g in lingonberhes, about 23 mg/100 g in black currants, about 14 mg/100 g in strawberries, and about 12 mg/100 g in cranberries (Mattila, P. et al., J. Agric. Food Chem. 2006, 54, 7193-7199).

[0033] In one embodiment of the invention, the berry is selected from the group of a strawberry, a raspberry, a blackberry, a blueberry, a Nn- gonberry, a cranberry, a redcurrant, a blackcurrant and/or any mixture thereof.

[0034] The sugar product of the present invention may contain varying amounts or percentages of these ingredients. The amount of sucrose in the product is from 55 to 99,5 weight-%, typically from 70 to 95 weight-% and preferably from 75 to 90 weight-%, based on the total weight of the product.

[0035] In one embodiment of the invention, the product of the present invention contains sucrose and a polyphenol extract, a berry extract, a berry concentrate or puree, a berry juice concentrate and/or a mixture thereof. A specific application of this embodiment is a product containing sucrose up to 99,5 weight-% of the total weight of the product and a polyphenol extract. Another specific application of the embodiment is a product containing sucrose and berry puree. In a product containing fresh berry puree and sucrose, the amount of sucrose typically varies between 10 and 30 weight-%, specifically from 15 to 25 weight-% based on the total weight of the product. The amount of berry puree typically varies between 70 and 90 weight-%, specifically from 75 to 85 weight-%, based on the total weight of the product. An amount of 150 g berry puree made of black currants, bilberries, cranberries and strawberries in 1 :1 :1 :1 (i.e., 37,5 g of each berry) contained about 750-800 mg polyphenol^ compounds. Accordingly, an amount of about 0.5 weight-% of polyphenol^ compounds based on a total weight of the product, was found to be effective in controlling the postprandial blood glucose and/or insulin level in a subject.

[0036] In another embodiment of the invention, the product of the present invention contains sucrose and dried berry extract, dried crushed berries, dried whole berries and/or dried berry powder. Specific application of this embodiment is a product containing sucrose and dried berry extract. In a product containing dried berry extract and sucrose, the amount of sucrose in relation to the amount of berry extract varies from 55:45 to 95:5, and is typically between 35:15 and 50:5. The product of the present invention provides a useful means for consumers to reduce the postprandial blood glucose level. Especially, the sugar product of the present invention provides a new way to help controlling the blood glucose level of a subject.

[0037] The following examples illustrate the present invention. The examples are not to be construed to limit the claims in any manner whatsoever.

EXAMPLE 1

[0038] A sugar product containing granulated sucrose and dried berry extract in amount of 45:15 was prepared. The dried berry extract was prepared from fresh berries (150 g) by evaporating the water to a yield of 15 g of dried extract. Granulated sucrose (45 g) and the dried berry extract (15 g) were mixed together and the mixing was continued until a homogenous mixture was achieved. The product contained added sucrose in an amount of 75 weight-% based on the total weight of the product.

[0039] Exploiting the same method sugar products containing sucrose up to 95 weight-% can be prepared.

EXAMPLE 2

[0040] A soft brown sugar type of product was prepared by mixing together 75 g granulated sucrose and 15 g berry extract. The obtained mixture was then coated with a berry juice concentrate having a dry matter content 40- 70⁰Bx. (Brix) measured using a refractometer. The amount of the berry juice concentrate was from 8 to 10 % of the total weight of the product. EXAMPLE 3

[0041] A total of 12 subjects participated in a randomized, controlled, crossover study that was carried out single blind for the study nurse.

[0042] The characteristics of the study subjects are shown in Table 1.

Table 1. Pretrial characteristics of the study subjects

Mean SD minimum - maximum

[0043] Each subject was studied in two 3-h meal tolerance tests, on separate days, at least 5 days apart. One of the two test meals was administered on each occasion in a randomized order in an open label design.

[0044] The subjects were randomized in blocks of four and the order of the test meals was randomly determined in each block for each subject. The subjects were tested at the same time of day under similar conditions and they acted as their own controls. The experiment began in the morning after a 12 h overnight fast. The fasting blood sample was obtained from a fingertip. The subjects were advised to consume the meal within 15 minutes. The mean meal duration was 9.9 (0.7) min for the test meal and 10.0 (1.0) min for the reference drink. The first bite/swig in the mouth was set as time 0 and the following fingertip capillary blood samples were taken at 15, 30, 45, 60, 90, 120, 150 and 180 min afterwards. During the 180 min period after the meal ingestion the subjects remained seated, but were allowed to walk to the next room for blood sampling and to the toilet. The study subjects were instructed to follow their habitual diet throughout the study. In the evening before the test each subject was told to consume a meal of choice and repeat that meal before the second test. There were no remarkable differences between the consumed meals in the evening before the two test days within the study subjects. In addition the subjects were requested to refrain from intensive physical activity day before the test days and abstain from alcohol two days before the test days, and to avoid berries in the prior evening meal. Smoking was prohibited on the morning before the test and during the test. [0045] One test meal and a reference drink were studied. The test meal included a mixed berry puree with 35 g sucrose. The mixed berry puree was made of black currants, bilberries, cranberries and strawberries. The total amount of berries in a portion of puree was 150 g, thus the amount of each berry in a portion was 37.5 g. The calculatory amount of polyphenols in the berry meal was about 0.42%. The total contents of sucrose, glucose and fructose for berry puree were analyzed by HPLC. The sugar composition of berry puree is presented in Table 2. The portion of berry puree was thawed before the test day and 35 g of sucrose was added on the puree just before eating by the study subject. 120 ml of water was served with the berry puree.

Table 2. The sugar composition of the berry puree

¹Frozen whole berries were thawed, homogenized and the sugar composition was analyzed. 2The berry puree was frozen, then thawed and the sugar composition was analyzed.

[0046] The control included 250 ml of water, 35 g of sucrose, 4.5 g of glucose and 5.1 g of fructose. The oral sucrose load was made by dissolving sucrose, glucose and fructose into water at room temperature on the day before the test day and it was stored in the refrigerator. The amounts of glucose and fructose were added to the sucrose load in purpose to achieve the similar profile and amounts of available carbohydrates as was found in the sucrose- sweetened berry puree.

RESULTS

[0047] The ingestion order of the berry puree and the control meal did not affect the results of this study. The body weight of the study subjects remained stable during the study. The fasting plasma glucose concentrations i.e baseline situation did not differ between the test meal occasions. The plasma glucose concentrations at 15 and 30 min after the berry puree meal were significantly lower than those after the control meal. In addition, the plasma glucose response at 150 min after the berry puree meal was signifi- cantly higher than at same timepoint after the control meal indicating delayed glucose response. The mean plasma glucose concentrations at different time points after the test meals are presented in Table 3 and Figure 1.

Table 3. Plasma glucose concentrations (mmol/l) at different timepoints (n=12)

¹ The overall difference in blood glucose concentrations between the berry puree and control meal analyzed with the GLM repeated measures.

[0048] The mean maximum plasma glucose concentration was reached later at 45 min after the berry puree meal and respectively at 30 min after the control meal. The difference in plasma glucose concentration between the meals at those time points is presented in Table 4.

Table 4. The difference in plasma glucose concentration between the berry puree and control at 30 and 45 min after ingestion of the meal

[0049] The maximum increase in plasma glucose concentration from the baseline was significantly smaller after ingestion of the berry puree meal than after ingestion of the control meal (Table 5). Compared to the control meal the peak increase was 1.0 (0.8) mmol/l and significantly smaller after ingestion of berry puree meal. The 0-180 min AUC after the berry puree meal was 16 (50) min x mmol/l smaller than after the control meal. Table 5. The maximum increase in plasma glucose concentration from the baseline after ingestion of the test meals and the areas under the glucose response curve (n=12). Mean (SD)

EXAMPLE 4

[0050] A total of 12 subjects participated in a randomized, controlled, crossover study that was carried out following the same study design and protocol as in Example 3.

[0051] The characteristics of the study subjects are shown in Table 6.

Table 6. Pretrial characteristics of the study subjects

Mean (SD) (minimum - maximum)

[0052] To determine plasma glucose and serum insulin concentrations, blood samples were collected through an indwelling plastic cannula inserted into a forearm vein at fasting and 15, 30, 45, 60, 90 and 120 min after starting to eat the meal. Plasma samples were taken into citrate-fluoride tubes. Blood samples were stored at -20⁰C before analyzing. Serum glucose concentrations were analyzed with the hexokinase method and serum insulin concentrations were analyzed with the immunoluminometric assay at Yhtyneet Medix Laboratoriot Oy, Finland.

[0053] The mean venous plasma glucose concentrations at different timepoints are presented in Table 7 and Figure 2. Table 7. Venous plasma glucose concentrations (mmol/l) at different timepoints (n=12)

¹ The overall difference in venous plasma glucose concentrations between the berry puree and control meal analyzed with the GLM repeated measures.

[0054] The fasting venous plasma glucose concentrations in baseline situation did not significantly differ between the test meal occasions. The ingestion of berry puree meal resulted in a significantly lower venous plasma glucose response in the postprandial phase at 15 min timepoint than did the control meal and the glucose response at 90 min after starting the berry puree meal was significantly higher than after the control meal. The peak venous plasma glucose concentration was reached at 30 min after meals. The maximum increase in venous plasma glucose from the baseline after ingestion of the test meals were 1.9 (0.9) mmol/l after the berry puree meal and 2.3 (0.9) mmol/l after the control meal.

[0055] The mean serum insulin concentrations at different time- points are presented in Table 8 and Figure 3.

Table 8. Serum insulin concentrations (mU/l) at different timepoints (n=12)

¹ The overall difference in serum insulin concentrations between the berry puree and control meal analyzed with the GLM repeated measures.

[0056] The mean fasting serum insulin concentrations in baseline situation did not differ significantly at beginning of each test meal occasions. The insulin concentrations were significantly lower at 15 min after starting the berry puree meal than after the control meal and the postprandial insulin response was significantly higher at 90 min and 120 min after starting the berry puree meal compared to the control meal. The peak insulin concentration was reached at 30 min after the meals. The maximum increase in serum insulin from baseline after ingestion of test meals differed significantly between the meals [mean difference 6.3 (7.8) mU/l,] being 16.8 (10.1 ) mU/l after the berry puree meal and 23.1 (8.5) mU/l after the control meal.

[0057] Soluble dietary fiber is known to attenuate postprandial glucose responses after carbohydrate-rich meals. The estimated dietary fiber content of the berry puree meal used in Examples 3 and 4 is about 5.4 g, of which approximately 70% is insoluble. Thus, the reduced glycaemic and insulin responses are not solely explained by the fiber content of the berry meal.

[0058] The ingestion of sucrose-sweetened berries produced a more favorable postprandial glycemic response than the control without berries. A mixture of berries rich in polyphenols delays and attenuates postprandial glycemic response after sucrose ingestion and simultaneously reduces postprandial insulin response in healthy adult subjects. [0059] It will be obvious to a person skilled in the art that, as the technology advances, the inventive concept can be implemented in various ways. The invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.

Claims

1. A sugar product comprising sucrose and at least one berry polyphenol.

2. The sugar product according to claim 1 wherein the polyphenol is in a form of a polyphenol extract, a berry extract, berry concentrate or puree, a berry juice concentrate and/or a mixture thereof.

3. The sugar product according to claim 1 wherein the polyphenol is in a form of dried crushed berries, fresh crushed berries, dried whole berries, berry powder and/or a mixture thereof.

4. The sugar product according to any one of claims 1 to 3 wherein the berry is a strawberry, a raspberry, a blackberry, a blueberry, a lingonberry, a cranberry, a red currant, a black currant and/or any mixture thereof.

5. The sugar product according to any one of claim 1 to 4, wherein sucrose is in the form of granulated sugar.

6. The sugar product according to any one of claim 1 to 5 wherein the product contains sucrose at least 75 weight-% based on the total weight of the product.

7. The sugar product according to claim 6 wherein the product contains sucrose from 75 to 95 weight-% based on the total weight of the product.

8. Use of at least one berry polyphenol in the manufacture of a sugar product for reducing and/or lowering the postprandial blood glucose and/or insulin concentration wherein the polyphenol and sucrose are ingested essentially simultaneously.

9. The use according to claim 8, wherein the polyphenol is a polyphenol extract, a berry extract, a berry concentrate or puree, a berry juice concentrate, a dried crushed berry, a dried whole berry, dried berry powder and/or a mixture thereof.

10. A berry polyphenol for use in reducing and/or lowering the postprandial blood glucose and/or insulin concentration wherein the polyphenol is ingested essentially simultaneously with sucrose.

11. The sugar product according to claim 1 for use in reducing and/or lowering the postprandial blood glucose and/or insulin concentration.

12. A method for reducing and/or lowering the postprandial blood glucose and/or insulin concentration of a subject by administering at least one berry derived polyphenol and sucrose to the subject.

13. The method of claim 12 wherein the polyphenol is a polyphenol extract, a berry extract, a berry concentrate or puree, a berry juice concentrate, a dried crushed berry, a dried whole berry, dried berry powder and/or a mixture thereof.

14. The method according to claim 12 or claim 13 wherein the polyphenol is administered before, simultaneously or after the administration of sucrose.

15. A sugar product according to claim 1 wherein the product is pro- cued by coating the granulated sugar with a berry juice concentrate.

16. A sugar product according to claim 15, wherein a soft brown sugar type product is produced by a) mixing the granulated sugar with berry powder, extract or another dried berry preparation, and b) coating the obtained mixture with a berry juice concentrate.