Process for preparing oligo-saccharide enhanced milk products

Abstract

The subject invention aims to solve the problem of production of glucose accompanying the production of galactooligosaccharides after milk raw material is treated with lactase, by additionally adding transglucosidase to convert glucose to functional isomalto-oligosaccharide. The subject invention relates to a process for the production of a milk product enhanced with oligo-saccharides, characterized in that lactase and transglucosidase are used to treat milk raw materials. The subject invention further relates to the milk product of the process of the invention, whose oligo-saccharide content reaches a functional level. Human physiological effect assays confirm that the milk product increases intestinal probiotics, reduces harmful intestinal bacteria, improves the intestinal bacterial flora, reduces blood total cholesterol, reduces blood LDL cholesterol, increases blood HDL cholesterol, and improves the immunity, and may be used as low glycemic index (GI) dietary supplements.

Claims

1. A process for the production of a milk product enriched with galactooligosaccharide and isomalto-oligosaccharide and having reduced lactose and glucose contents, comprising treating milk raw materials with lactase and transglucosidase, comprising the following steps: (1) providing the milk raw materials, wherein the milk raw materials comprise about 10 to 60% (w/w) solid; (2) adding about 0.01 to 0.5% (w/w) lactase and about 0.01 to 1.0% (w/w) transglucosidase to the milk raw materials; (3) reacting at about 50° C. for about 60 minutes, and (4) subjecting the product of step (3) to heating and enzyme inactivation followed by cooling, wherein after treatment, the content of galactooligosaccharide is about 1.0 (g/100 g) or more and the content of isomalto-oligosaccharide is about 0.5 (g/100 g) or more.

2. The process according to claim 1, wherein the milk raw materials are cow milk, goat milk or sheep milk.

3. The process according to claim 2, wherein the milk raw materials are cow milk.

4. The process according to claim 1, wherein the lactase is from Kluyveromyces and the transglucosidase is from Aspergillus.

5. The process according to claim 1, further comprising: step (5): subjecting the product of step (4) to ultra-high temperature (UHT) pasteurization.

6. The process according to claim 5, further comprising packaging the milk product obtained from step (5) with aseptic cold filling technology.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 relates to the blood glucose change after the subjects ingested a glucose aqueous solution containing 25 g glucose, wherein 0 minutes represents fasting, and 15, 30, 60, 90 and 120 minutes respectively represent 15, 30, 60, 90 and 120 minutes after ingestion of the glucose aqueous solution.

(2) FIG. 2 relates to the blood glucose change after the subjects ingested an oligosaccharide milk product (containing 25 g saccharides) of the present invention, wherein 0 minutes represents fasting, and 15, 30, 60, 90 and 120 minutes respectively represent 15, 30, 60, 90 and 120 minutes after drinking the milk product of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

(3) The present invention utilizes an enzymatic degradation method comprising using lactase and transglucosidase to treat milk raw materials to produce a milk product enriched with oligosaccharides. The enzymatic degradation method of the present invention can simultaneously reduce lactose and glucose contents in a milk product.

(4) Any milk raw materials are suitable in the present invention, including but not limited to cow milk, goat milk and sheep milk, preferably cow milk. The milk raw material may be fresh milk or modified milk.

(5) In one embodiment, the milk raw material comprises a solid content of about 10 to 60% (w/w), preferably about 30 to 50% (w/w), more preferably about 40% (w/w).

(6) Lactase suitable in the method of the present invention may be of any origin, including but not limited to lactase from Aspergillus, Saccharomyces and Kluyveromyces, preferably from Kluyveromyces.

(7) In one embodiment, the amount of lactase to be added is, based on the weight of lactose of the milk raw material, about 0.01 to 0.5% (w/w), preferably about 0.05 to 0.2% (w/w), more preferably about 0.1% (w/w).

(8) Transglucosidase suitable in the method of the present invention may be of any origin, including but not limited to transglucosidase from Aspergillus and Acremonium, preferably from Aspergillus, such as Aspergillus niger.

(9) In one embodiment, the amount of transglucosidase to be added is, based on the weight of lactose of the milk raw material, about 0.01 to 1.0% (w/w), preferably about 0.02 to 0.6% (w/w), more preferably about 0.05 to 0.3% (w/w).

(10) In one embodiment, the milk raw material reacts with lactase and transglucosidase at a temperature of about 40 to 60° C., preferably about 45 to 55° C., more preferably about 50° C.

(11) According to the present invention, the milk raw material reacts with lactase and transglucosidase for a suitable period of time so that a milk product enriched with oligosaccharides including galactooligosaccharide and isomalto-oligosaccharide is produced. In one embodiment, the milk raw material reacts with lactase and transglucosidase for about 30 to 90 minutes, preferably about 40 to 80 minutes, more preferably about 50 to 70 minutes, most preferably about 60 minutes.

(12) In one embodiment, the milk product produced by the method of the present invention is further enriched with lactoprotein solid. In one embodiment, the amount of lactoprotein solid contained in the milk product produced by the method of the present invention is about 10 to 18% (w/w), preferably about 12 to 16% (w/w), more preferably about 14% (w/w).

(13) The milk product produced by the method of the present invention is enriched with oligosaccharides. In one embodiment, the amount of galactooligosaccharide contained in the milk product produced by the method of the present invention is about 1.0 (g/100 g) or more, for example, about 1.0 to 7.0 (g/100 g); preferably about 3.0 (g/100 g) or more, for example, about 3.0 to 7.0 (g/100 g); more preferably about 5.0 (g/100 g) or more, for example, about 5.0 to 7.0 (g/100 g). In one embodiment, the amount of isomalto-oligosaccharide contained in the milk product produced by the method of the present invention is about 0.5 (g/100 g) or more, for example, about 0.5 to 4.0 (g/100 g); preferably about 2.0 (g/100 g) or more, for example, 2.0 to 4.0 (g/100 g); more preferably about 3.0 (g/100 g) or more, for example, 3.0 to 4.0 (g/100 g).

(14) In one embodiment, the method of the present invention comprises the following steps:

(15) (1) providing a milk raw material containing about 10 to 60% (w/w) solid, preferably a milk raw material containing about 30 to 50% (w/w) solid, more preferably a milk raw material containing about 40% (w/w) solid;

(16) (2) adding about 0.01 to 0.5% (preferably about 0.05 to 0.2%, more preferably about 0.1%) (w/w) lactase and about 0.01 to 1.0% (preferably about 0.02 to 0.6%, more preferably about 0.05 to 0.3%) (w/w) transglucosidase to said milk raw material; and

(17) (3) reacting at about 40 to 60° C. (preferably about 45 to 55° C., more preferably about 50° C.) for about 30 to 90 minutes (preferably about 40 to 80 minutes, more preferably about 50 to 70 minutes, most preferably about 60 minutes).

(18) The method of the present invention further comprises an enzyme inactivation step. Any known methods for inactivating an enzyme are suitable in the present invention.

(19) In one embodiment, the method of the present invention further comprises step (4): heating liquid milk obtained from step (3) to inactivate enzymes followed by cooling. In one embodiment, the temperature of step (4) for heating and inactivating enzymes is 70 to 80° C., and the temperature is cooled to 10 to 20° C.

(20) The milk product produced according to the method of the present invention can be sterilized by any known sterilizing method and then packaged.

(21) In one embodiment, the method of the present invention further comprises step (5): subjecting the product obtained from step (4) to ultra-high temperature (UHT) pasteurization. In one embodiment, the UHT pasteurization of step (5) is conducted at 140° C. for 30 seconds.

(22) In one embodiment, the milk product of the present invention having undergone the sterilization process of step (5) is further packaged by aseptic cold filling technology.

(23) In one embodiment, the milk raw material is cow milk containing 40% of solid. After addition of 0.1% (w/w) lactase and 0.05% (w/w) transglucosidase and reaction at 50° C. for 60 minutes, the obtained milk product contained 14.32% (w/w) lactoprotein solid, 5.64 (g/100 g) galactooligosaccharide and 2.2 (g/100 g) isomalto-oligosaccharide.

(24) In one embodiment, the milk raw material is cow milk containing 40% of solid. After addition of 0.1% (w/w) lactase and 0.1% (w/w) transglucosidase and reaction at 50° C. for 60 minutes, the obtained milk product contained 14.13% (w/w) lactoprotein solid, 5.77 (g/100 g) galactooligosaccharide and 2.41 (g/100 g) isomalto-oligosaccharide.

(25) In one embodiment, the milk raw material is cow milk containing 40% of solid. After addition of 0.1% (w/w) lactase and 0.2% (w/w) transglucosidase and reaction at 50° C. for 60 minutes, the obtained milk product contained 14.50% (w/w) lactoprotein solid, 6.10 (g/100 g) galactooligosaccharide and 2.38 (g/100 g) isomalto-oligosaccharide.

(26) In one embodiment, the milk raw material is cow milk containing 40% of solid. After addition of 0.1% (w/w) lactase and 0.3% (w/w) transglucosidase and reaction at 50° C. for 60 minutes, the obtained milk product contained 14.08% (w/w) lactoprotein solid, 6.76 (g/100 g) galactooligosaccharide and 3.16 (g/100 g) isomalto-oligosaccharide.

(27) Experiments prove that by drinking the milk product of the present invention enriched with oligosaccharides, the levels of triglycerides, total cholesterol in the blood, and low-density lipoprotein cholesterol can be effectively decreased, and the level of high-density lipoprotein cholesterol can be effectively increased.

(28) Accordingly, the present invention provides a use of the milk product of the present invention enriched with oligosaccharides for modulating blood lipids, preferably for reducing blood triglyceride level, reducing the level of total cholesterol in blood, reducing the level of low-density lipoprotein cholesterol in blood, and/or increasing the level of high-density lipoprotein cholesterol in blood.

(29) Further, experiments prove that by drinking the milk product of the present invention enriched with oligosaccharides, probiotics such as Lactobacillus spp. and Bifidobacterium spp. in the intestinal tract can be increased and harmful bacteria such as Clostridium perfringens can be reduced, which can help improve the intestinal bacterial flora.

(30) Accordingly, the present invention provides a use of the milk product of the present invention enriched with oligosaccharides for improving intestinal function, including increasing intestinal probiotics, reducing intestinal harmful bacteria, and/or improving the intestinal bacterial flora.

(31) Furthermore, experiments prove that by drinking the milk product of the present invention enriched with oligosaccharides, immunity can be improved.

(32) Accordingly, the present invention also provides a use of the milk product of the present invention enriched with oligosaccharides for improving immunity.

(33) According to the GI values of various foods as measured by Brand-Miller et al (2003, 2008), by using glucose as reference food, the food with a GI value less than 55 is a low GI food, the food with a GI value between 55 and 69 is a medium GI food, and the food with a GI value greater than 70 is a high GI food. Experiments prove that the milk product of the present invention enriched with oligosaccharides has a GI value of less than 55, and thus is a low GI food.

(34) The milk product of the present invention enriched with oligosaccharides, the process of producing the same and use thereof in the present invention are further illustrated in the following non-limitative examples. These examples should not be deemed as overly limiting the present invention. Persons of ordinary skill in the art can modify or change the examples described below without deviating from the spirit or scope of the present invention.

EXAMPLES

(35) The following examples are provided only for the purpose of further describing the present invention and are not intended for limiting the scope of the present invention.

Example 1

(36) According to the content of lactose, whole milk (solid content of 12%, w/w) (CNS3056) was added with 0.1% lactase from Kluyveromyces followed by reaction at 50° C. for 0 to 2 hours. The obtained milk product contained a lactoprotein content of 3.06, 3.07, 3.03, 3.08% (w/w) and a galactooligosaccharide content of 0, 0.14, 0.61, 0.35 (g/100 g) at 0, 30, 60, 120 minutes, respectively.

Example 2

(37) According to the content of lactose, whole milk (solid content of 40%, w/w) (CNS3056) was added with 0.1% lactase from Kluyveromyces followed by reaction at 50° C. for 0 to 2 hours. The obtained milk product contained a lactoprotein content of 14.22, 14.12, 14.01, 14.15% (w/w) and a galactooligosaccharide content of 0, 1.5, 5.46, 3.75 (g/100 g) at 0, 30, 60, 120 minutes, respectively.

(38) The reaction conditions and galactooligosaccharide content of Examples 1 and 2 are shown in the table below:

(39) TABLE-US-00001 TABLE 1 Galactooligosaccharide content produced at different reaction times final liquid milk product milk product source of after enzyme (milk solid milk solid enzyme reaction lactoprotein treatment content 12%) content (reaction time content GOS content GOS content Example (%, w/w) temperature) (minutes) (%) (g/100 g) (g/100 g) Example 12 Kluyveromyces 0 3.06 0 0 1 (50° C.) 30 3.07 0.14 0.14 60 3.03 0.61 0.61 120 3.08 0.35 0.35 Example 40 Kluyveromyces 0 14.22 0 0 2 (50° C.) 30 14.12 1.5 0.45 60 14.01 5.46 1.64 120 14.15 3.75 1.13

Example 3

(40) Milk powder was homogeneously dissolved in 55° C. water to form a high concentration milk (solid content of 40%, w/w), then added with 0.1% lactase from Kluyveromyces followed by reaction at 50° C. for 60 minutes. The milk product obtained at 60 minutes contained a lactoprotein content of 14.15% (w/w), a galactooligosaccharide content of 5.16 (g/100 g) and an isomalto-oligosaccharide content of 0 (g/100 g).

Example 4

(41) Milk powder was homogeneously dissolved in 55° C. water to form a high concentration milk (solid content of 40%, w/w), then added with 0.1% lactase from Kluyveromyces and 0.05% transglucosidase from Aspergillus followed by reaction at 50° C. for 60 minutes. The milk product obtained at 60 minutes contained a lactoprotein content of 14.32% (w/w), a galactooligosaccharide content of 5.64 (g/100 g) and an isomalto-oligosaccharide content of 2.22 (g/100 g).

Example 5

(42) Milk powder was homogeneously dissolved in 55° C. water to form a high concentration milk (solid content of 40%, w/w), then added with 0.1% lactase from Kluyveromyces and 0.1% transglucosidase from Aspergillus followed by reaction at 50° C. for 60 minutes. The milk product obtained at 60 minutes contained a lactoprotein content of 14.13% (w/w), a galactooligosaccharide content of 5.77 (g/100 g) and an isomalto-oligosaccharide content of 2.41 (g/100 g).

Example 6

(43) Milk powder was homogeneously dissolved in 55° C. water to form a high concentration milk (solid content of 40%, w/w), then added with 0.1% lactase from Kluyveromyces and 0.2% transglucosidase from Aspergillus followed by reaction at 50° C. for 60 minutes. The milk product obtained at 60 minutes contained a lactoprotein content of 14.50% (w/w), a galactooligosaccharide content of 6.1 (g/100 g) and an isomalto-oligosaccharide content of 2.38 (g/100 g).

Example 7

(44) Milk powder was homogeneously dissolved in 55° C. water to form a high concentration milk (solid content of 40%, w/w), then added with 0.1% lactase from Kluyveromyces and 0.3% transglucosidase from Aspergillus followed by reaction at 50° C. for 60 minutes. The milk product obtained at 60 minutes contained a lactoprotein content of 14.08% (w/w), a galactooligosaccharide content of 6.76 (g/100 g) and an isomalto-oligosaccharide content of 3.16 (g/100 g).

(45) The reaction conditions and the contents of lactoprotein, galactooligosaccharide and isomalto-oligosaccharide are shown in the table below:

(46) TABLE-US-00002 TABLE 2 Oligosaccharide content produced from different concentrations of transglucosidase added final liquid milk product after milk product milk enzyme treatment (milk solid solid source of enzyme reaction GOS IMO content 12%) content (reaction temperature) time lactoprotein content content GOS/IMO Example (% w/w) amount (%) (minutes) content (%) (g/100 g) (g/100 g) (g/100 g) Example 40 Kluyveromyces Aspergillus 0 0 0 0 3 (50° C.) (50° C.) 60 14.15 5.16 0 1.55/0   0.1 0   Example Aspergillus 0 0 0 0 4 (50° C.) 60 14.32 5.64 2.22 1.69/0.67  0.05 Example Aspergillus 0 0 0 0 5 (50° C.) 60 14.13 5.77 2.41 1.73/0.72 0.1 Example Aspergillus 0 0 0 0 6 (50° C.) 60 14.50 6.10 2.38 1.83/0.71 0.2 Example Aspergillus 0 0 0 0 7 (50° C.) 60 14.08 6.76 3.16 2.03/0.95 0.3

(47) Liquid milk obtained from Examples 3 to 7 was subjected to heating and enzyme inactivation (70 to 80° C.) followed by cooling to 10 to 20° C. The resulting product was then subjected to UHT pasteurization (140° C. for 30 seconds), followed by packaging using aseptic cold filling technology.

Example 8: Evaluation of the Function of Blood Lipid Modulation

(48) The experiment is primarily focused on the effect of the oligosaccharide milk product of the present invention on the blood lipids of adults. The experiment is a single-blind parallel experiment. 24 subjects aged 22 to 64 were recruited, excluding those having any major diseases (such as liver, kidney, gastrointestinal, cardiovascular diseases or mental illness) or taking any blood lipid-lowering drugs or supplements. The subjects were randomly assigned to the experimental group or control group. The 12 subjects in the experimental group drank the oligosaccharide milk product of the present invention, and the 12 subjects in the control group drank a milk product not belonging to the present invention. Each subject drank a bottle of the oligosaccharide milk product of the present invention (or the milk product not belonging to the present invention) at breakfast and after lunch, (270 ml per bottle, two bottles (540 ml in total) per day) for 8 weeks followed by a two-week emptying phase. Blood from the subjects was collected at weeks 0, 4, 8 and 10 of the experiment and the diet of the subjects was recorded for three days to ensure that the diet was not changed during experimentation. No blood lipid-lowering drugs or supplements were taken during experimentation.

(49) Levels of triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) in the blood of the subjects were measured before commencement of the experiment and at weeks 4, 8 and 10 during the experiment. The results are shown in Table 3 below.

(50) TABLE-US-00003 TABLE 3 Blood lipid changes after the subjects ingested the oligosaccharide milk product Control Group (n = 12) Experimental Group (n = 12) baseline Week 4 Week 8 Week 10 baseline Week 4 Week 8 Week 10 TG  92.1 ± 33.5  93.6 ± 32.7  90.4 ± 29.0  89.3 ± 34.0  91.1 ± 47.3 88.8 ± 59.3 74.4 ± 48.5* 77.4 ± 40.9 (mg/dL) TC 216.9 ± 16.9 222.3 ± 18.2 220.2 ± 21.4 211.1 ± 22.7 220.8 ± 15.7 207.7 ± 20.9* 200.3 ± 13.0*† 196.2 ± 17.3* (mg/dL) HDL-C  59.8 ± 12.6  59.7 ± 13.9  59.9 ± 14.1  60.1 ± 14.0  60.9 ± 11.3  67.0 ± 11.6* 66.0 ± 10.2* 62.3 ± 10.0 (mg/dL) LDL-C 144.0 ± 21.8 146.1 ± 23.1 144.6 ± 19.6 141.1 ± 24.6 141.0 ± 21.8 129.0 ± 27.5* 125.6 ± 15.6*† 125.3 ± 18.4* (mg/dL) Experimental data is expressed by mean value ± standard deviation (SD), n = 12 *p < 0.05 represents that data in the same group are significantly different from baseline †p < 0.05 represents that data in the same week are significantly different from Control Group

(51) The above results demonstrate that by drinking the oligosaccharide milk product of the present invention for 8 weeks, the levels of triglyceride, total cholesterol and low-density lipoprotein cholesterol in the blood can be effectively decreased, and the level of high-density lipoprotein cholesterol can be effectively increased.

Example 9: Evaluation of the Improvement of Gastrointestinal Function

(52) Healthy adult subjects drank 540 ml of the oligosaccharide milk product of the present invention per day for 4 weeks. The bacterial numbers of Coliform organisms, Lactobacillus spp., Bifidobacterium spp., and Clostridium perfringens in the feces samples of the subjects were measured at weeks 0, 2, 4 and 5. The results are shown in Table 4.

(53) TABLE-US-00004 TABLE 4 Changes of intestinal flora after the subjects ingested the oligosaccharide milk product Week 0 2 4 5 Log 10 CFU/g (feces weight) Total anaerobes 11.20 ± 0.62  11.49 ± 0.35  11.06 ± 0.49  11.32 ± 0.92  Coliform organisms 7.43 ± 0.45 7.81 ± 0.61 7.33 ± 1.10 7.04 ± 0.85 Lactobacillus spp. 9.41 ± 0.68 10.41 ± 0.57* 10.58 ± 0.64* 10.53 ± 0.81* Bifidobacteriurn spp. 9.67 ± 0.64 10.74 ± 0.35* 10.53 ± 0.76* 10.88 ± 0.63* Clostridium perfringens 5.79 ± 0.81  4.21 ± 0.38*  4.71 ± 0.31* 5.36 ± 0.61 Experimental data is expressed by Mean ± SD, n = 8 ∘ *represents significant difference P < 0.05 compared to Week 0

(54) As demonstrated in the table above, the bacterial numbers of both Bifidobacterium spp. and Lactobacillus spp. are significantly increased (P<0.05), the bacterial numbers of Clostridium perfringens are significantly decreased (P<0.05), and the bacterial numbers of Coliform organisms have no significant change. The results demonstrate that for the healthy adults who ingested 540 ml of the oligosaccharide milk product of the present invention per day, the probiotics in the intestinal tract are increased and the harmful bacteria are decreased. The oligosaccharide milk product of the present invention can improve intestinal bacterial flora and has a health-care effect.

Example 10: Evaluation of Immune Modulatory Function

(55) The experiment mainly studies the immune modulatory efficacy of the oligosaccharide milk product of the present invention. Through evaluating specific immune modulatory function and non-specific immune modulatory function, the animal experiments prove that the product of the present invention is useful in:

(56) 1. promoting the ability of immune cells to proliferate;

(57) 2. promoting the activity of phagocytes;

(58) 3. promoting the activity of nature killer cells;

(59) 4. modulating cytokine secretion; and

(60) 5. elevating antibody levels in the serum.

(61) Tables 5 and 6 demonstrate the experimental results on the modulation of specific and non-specific immune functions.

(62) TABLE-US-00005 TABLE 5 Summary of the experimental results of the modulation of specific immune functions Medium Measured Items Low dose dose High dose Ability of immune Con A — P < 0.05↑ P < 0.05↑ cells to proliferate LPS — P < 0.05↑ P < 0.05↑ OVA P < 0.05↑ P < 0.05↑ P < 0.05↑ Function of cytokine IL-2 Con A P < 0.05↑ P < 0.05↑ P < 0.05↑ secretion LPS — — — OVA P < 0.05↑ P < 0.05↑ P < 0.05↑ IL-4 Con A — — — LPS — — — OVA — — P < 0.05↓ IL-5 Con A P < 0.05↓ — P < 0.05↓ LPS — — — OVA P < 0.05↓ P < 0.05↓ P < 0.05↓ TNF- Con A P < 0.05↓ P < 0.05↓ P < 0.05↓ LPS P < 0.05↓ P < 0.05↓ P < 0.05↓ OVA — — P < 0.05↓ IFN- Con A P < 0.05↑ P < 0.05↑ P < 0.05↑ LPS — — — OVA — — — Lymphocytes T4 cell — — — subpopulation T8 cell — — — analysis T cell — — — B cell — — — NK cell — — — Serum antibody anti-OVA-IgG1 — P < 0.05↓ — production anti-OVA-Ig2a P < 0.05↑ P < 0.05↑ P < 0.05↑ anti-OVA-IgE P < 0.05↓ P < 0.05↓ P < 0.05↓ — represents no significant difference compared to the negative control group P < 0.05↑ represents significant increase compared to the negative control group P < 0.05↓ represents significant decrease compared to the negative control group

(63) TABLE-US-00006 TABLE 6 Summary of the experimental results of the modulation of non- specific immune functions Group Medium Measured Items Low dose dose High dose Ability of Con A P < 0.05↑ P < 0.05↑ P < 0.05↑ immune cells LPS P < 0.05↑ P < 0.05↑ P < 0.05↑ to proliferate Function of IL-2 Con A P < 0.05↑ P < 0.05↑ P < 0.05↑ cytokine LPS — — P < 0.05↑ secretion IL-4 Con A — — — LPS P < 0.05↓ P < 0.05↓ P < 0.05↓ IL-5 Con A P < 0.05↓ P < 0.05↓ P < 0.05↓ LPS — — — TNF- Con A P < 0.05↓ P < 0.05↓ P < 0.05↓ LPS P < 0.05↓ P < 0.05↓ P < 0.05↓ IFN- Con A — P < 0.05↑ P < 0.05↑ LPS — — — Lymphocytes T4 cell — — — subpopulation T8 cell — — — analysis T cell — — — B cell — — — NK cell — — — Serum antibody IgG — P < 0.05↑ P < 0.05↑ production IgM — P < 0.05↑ P < 0.05↑ IgA P < 0.05↑ P < 0.05↑ P < 0.05↑ IgE — — — Activity of NK E/T ratio = 5:1 P < 0.05↑ P < 0.05↑ P < 0.05↑ cells E/T ratio = 10:1 — P < 0.05↑ P < 0.05↑ E/T ratio = 25:1 P < 0.05↑ P < 0.05↑ P < 0.05↑ Activity of M.O.I. = 12.5 — P < 0.05↑ P < 0.05↑ phagocytes in M.O.I. = 25 — P < 0.05↑ P < 0.05↑ abdominal cavity M.O.I. = 50 P < 0.05↑ P < 0.05↑ P < 0.05↑ — represents no significant difference from negative control group P < 0.05↑ represents significant increase over negative control group P < 0.05↓ represents significant decrease over negative control group

(64) The above experimental results demonstrate that the oligosaccharide milk product of the present invention has an efficacy in modulating immune functions.

Example 11: Evaluation of GI

(65) A free-living and self-diet control design was utilized for the experiment. Each subject enrolled in the GI test participated in two tests, including one standard food test (glucose aqueous solution) and one experimental food test (the oligosaccharide milk product of the present invention). The subjects were starved for 10 to 12 hours at night before testing. On the morning of testing, the subjects were first examined for body status, and then their fasting blood was collected by a nurse. Then, the subjects were given an experimental food containing 25 g saccharides. Venous blood was collected at 15, 30, 60, 90 and 120 minutes after ingestion. Each time about 3 ml blood was collected.

(66) At fasting and after ingestion of the standard experimental food, i.e., the glucose aqueous solution, the average blood glucose levels at fasting, 15 minutes, 30 minutes, 60 minutes, 90 minutes and 120 minutes were 84.2±4.5, 104.0±10.4, 110.0±11.7, 81.8±18.5, 70.7±14.2 and 70.7±7.5 mg/dL, respectively; and the area under the curve (AUC) of total blood glucose was 846.6. When using glucose aqueous solution as the standard test food, the GI value was 100. The values and diagram of blood glucose change are shown in Table 7 and FIG. 1, respectively.

(67) TABLE-US-00007 TABLE 7 Blood glucose change and AUC.sup.1,2 after the subjects ingested a glucose aqueous solution containing 25 g glucose Time (minutes) 0 15 30 60 90 120 Blood glucose 84.2 ± 4.5 104.0 ± 10.4 110.0 ± 11.7 81.8 ± 18.5 70.7 ± 14.2 70.7 ± 7.5 (mg/dL) AUC 148.8 342.9 354.9 Total: 846.6 GI value 100 .sup.1all values are expressed by Mean ± SD .sup.20 minutes representing fasting, and 15, 30, 60, 90 and 120 minutes respectively representing 15, 30, 60, 90 and 120 minutes after ingestion of glucose aqueous solution

(68) At fasting and after ingestion of the oligosaccharide milk product (containing 25 g oligosaccharides) of the present invention, the average blood glucose levels at fasting, 15 minutes, 30 minutes, 60 minutes, 90 minutes and 120 minutes were 89.1±5.8, 93.9±5.2, 87.4±10.1, 76.0±9.0, 77.4±7.2 and 79.5±6.2 mg/dL, respectively; and the area under the curve (AUC) of total blood glucose was 62.9. By using glucose aqueous solution as the standard for comparison, the GI value was 7.4. The values and diagram of blood glucose change are shown in Table 8 and FIG. 2, respectively.

(69) TABLE-US-00008 TABLE 8 Blood glucose change and AUC.sup.1,2 after the subject ingested the oligosaccharide milk product (containing 25 g oligosaccharides) of the present invention Time (minutes) 0 15 30 60 90 120 Blood glucose 89.1 ± 5.8 93.9 ± 5.2 87.4 ± 10.1 76.0 ± 9.0 77.4 ± 7.2 79.5 ± 6.2 (mg/dL) AUC 36.2 26.7 Total: 62.9 GI value 7.4 .sup.1all values are expressed by Mean ± SD .sup.20 minutes representing fasting, and 15, 30, 60, 90 and 120 minutes respectively representing 15, 30, 60, 90 and 120 minutes after drinking the test samples

(70) From the above experiments, it is known that the GI value of the oligosaccharide milk product of the present invention is 7.4, so the product is a low GI food.