JP7470944B2 - Poultry feed and meat - Google Patents

Description

The present invention relates to poultry feed and poultry meat obtained by feeding said feed, and more specifically to poultry feed containing D-psicose, poultry meat whose meat quality has been improved by said poultry feed, a method for producing poultry meat whose meat quality has been improved, and a method for improving the meat quality of poultry meat.

The texture and flavor of meat varies depending on the part of the animal. For example, in the case of chicken, thigh meat is juicy and has a strong flavor, while breast meat is tough and has little flavor. In the case of beef, thigh meat is tough, while fillet meat is soft, and loin meat is soft and has a strong flavor.

In an attempt to improve the quality of meat, meat processing methods have been studied for a long time, and currently, tumbling (soaking in seasoning liquid) and injection (injecting fat, etc.) of meat chunks are commonly performed. Examples of additives used in these processes include a meat tenderizer made of a sugar composition containing 35% or more maltotriose (Patent Document 1), a meat tenderizer containing sugar and caramel with a pH of 8 to 11 (Patent Document 2), and an O/W type emulsion composition containing fats and oils and sodium lactate (Patent Document 3).

On the other hand, methods of improving meat quality by improving the livestock breeding methods and feed given to the livestock that will produce the meat, rather than processing the meat, are also being considered. Improved livestock feeds include poultry feed containing astaxanthin (Patent Document 4) and cattle feed with added spices and vitamin E (Patent Document 5).

On the other hand, D-psicose (hereinafter also referred to as D-allulose) is well known for its blood sugar rise suppression effect in tests using rats and humans, and it has been disclosed that eggs with small weight and size can be obtained by feeding egg-laying hens a feed prepared to contain 2% "rare sugar-containing syrup" in which D-psicose accounts for 7% of the total solids (Patent Document 6). It has also been disclosed that when "mixed liquid sugar by-products from rare sugar production" containing 1.15% D-psicose was added to drinking water at 1% or 5%, and this was fed to broilers (cup breed) and raised, the heating loss of the extracted superficial pectoral muscle (breast meat) was small, but the breaking stress was large (Non-Patent Document 1).

In other words, it has been confirmed that feeding egg-laying hens chicken feed containing 0.1% D-psicose results in small eggs being laid even in the later stages of the egg-laying season, and that feeding broilers drinking water containing 0.01% or 0.06% D-psicose reduces cooking loss in breast meat and increases breaking stress. However, the liquid sugars used in these experiments not only contained rare sugars other than D-psicose, but were mixed liquid sugars containing more than 70% fructose and glucose, so it cannot be said that any effect due to D-psicose itself has been confirmed.

JP 2015-181415 A JP 2013-247896 A JP 2010-068772 A JP 2011-055792 A Japanese Patent Application Laid-Open No. 11-196776 JP 2019-041710 A

Yasuhiro Izumikawa et al., "Feeding Test of Mixed Sugar Solution to Chickens," Kagawa Livestock Research Institute Report (2012), Vol. 47, pp. 29-37

The object of the present invention is to provide a feed for improving the meat quality of poultry, to provide poultry meat with improved meat quality by feeding the feed to poultry, and to provide a method for producing poultry meat with improved meat quality or a method for improving poultry meat quality.

The inventors fed chickens a specific amount of D-psicose as solid feed and examined the meat quality. They discovered that breast meat had a higher protein content, a stronger flavor, and both breast and thigh meat were more tender. These findings led to the completion of the present invention.

That is, the present invention is composed of the following [1] to [6], and the first invention is a poultry feed.
[1] A poultry feed for improving meat quality, comprising 0.3 to 3.0% by mass of D-psicose.
[2] The poultry feed according to the above-mentioned [1], wherein the meat quality improvement is one or more of an increase in protein content, an improvement in tenderness, and an enhancement in umami richness.
The second invention is a method for producing poultry meat.
[3] A method for producing poultry meat having improved meat quality, comprising feeding poultry feed containing 0.3 to 3.0% by mass of D-psicose to poultry for two weeks or more.
The third invention is poultry meat having improved meat quality.
[4] Poultry meat having improved meat quality, obtained by feeding poultry feed containing 0.3 to 3.0% by mass of D-psicose to poultry for two weeks or more.
The fourth invention is a method for improving the quality of poultry meat.
[5] A method for improving the quality of poultry meat, comprising feeding poultry feed containing 0.3 to 3.0 mass % of D-psicose to poultry for two weeks or more.
[6] The method for improving poultry meat quality described in [5] above, wherein the meat quality improvement is one or more of increasing the protein content, improving tenderness, and enhancing richness of flavor.

By using the poultry feed of the present invention, the breast part of poultry, which has low market value due to its low fat content and hard texture, can be made softer and more delicious, and the thigh part can be made even softer, further increasing the added value.

FIG. 13 is a diagram showing response values of each taste by a taste sensor for breast meat. FIG. 13 is a diagram showing response values of each taste from a taste sensor for thigh meat.

The "D-psicose" used in the present invention may be a commercially available product. An example of a product that contains a high amount of D-psicose is "Astraea" (manufactured by Matsutani Chemical Industry Co., Ltd.), and an example of a mixed product is "Rare Sugar Sweet" (manufactured by Matsutani Chemical Industry Co., Ltd.), which contains about 7% D-psicose. However, in the case of the latter mixed syrup, a powdering process is required to make it into chicken feed, and not only is there very little D-psicose, which is the active ingredient, but the majority is unnecessary D-glucose and D-fructose. Therefore, it is better to use a D-psicose-containing powder or crystal product that contains at least 15% by mass of D-psicose, preferably 20% by mass or more, and more preferably 30% by mass or more. D-psicose can be measured using a high-performance liquid chromatography method that is generally known as a method for analyzing sugars (for example, see Takamine et al., "Method for producing rare sugar-containing syrup using alkaline isomerization and the inhibitory effect of α-glucosidase," Applied Glycoscience (2015), Vol. 5, No. 1, pp. 44-49).

The concentration of D-psicose in the feed of the present invention is preferably 0.1% by mass or more in order to achieve the object of the present invention, and preferably does not exceed 5% in order to ensure that the effect of the present invention remains constant even if the concentration exceeds 10% by mass, and to prevent laxative effects. It is preferable to feed D-psicose to poultry in a range of 0.1 to 5% by mass, more preferably 0.3 to 3% by mass.

In addition to the active ingredient D-psicose, the poultry feed of the present invention preferably contains amino acids and amino acid salts, and from a nutritional standpoint, it is preferable to use proteins, peptides, fats and oils, and vitamins in combination. Furthermore, any combination of materials can be added as long as they do not inhibit the effects of the present invention and do not result in nutritional deficiencies or excesses.

The poultry feed of the present invention is not limited to chickens, but also includes turkeys, ducks, quails, wild ducks, etc.

The "improved meat quality" of the poultry meat of the present invention means that, compared to poultry meat that does not consume the poultry feed of the present invention, one or more of the following effects are achieved: the meat becomes softer (also called softening, including not hardening), the flavor and richness is enhanced, and the protein content is increased. Here, the softness of poultry meat can be determined by the numerical value at the maximum load point in a breaking strength analysis using a rheometer (e.g., CR-100 manufactured by Sun Scientific Co., Ltd., etc.) (the smaller this numerical value, the softer the meat), the protein content of poultry meat can be known by measuring the crude protein content using the Kjeldahl method (nitrogen-protein conversion factor is 6.25), and the flavor and richness can be measured as a numerical value (the higher this numerical value, the stronger the taste) using a taste sensor (such as the taste recognition device "TS-5000Z" manufactured by Intelligent Sensor Technology Co., Ltd.).

The above taste sensor evaluates taste in two ways: the "first taste," which is the taste experienced the moment food is ingested, and the "aftertaste," which is the persistent taste that remains after the food is swallowed. More specifically, the potential of the reference solution (a nearly tasteless solution containing 30 mM KCl and 0.3 mM tartaric acid, equivalent to human saliva) is set to zero, and the potential difference between the reference solution and the sample solution is measured as the "first taste." The sensor is then lightly washed and the potential difference when the reference solution is measured again is measured as the "aftertaste." The taste items measured as the "first taste" are sourness, bitterness, astringent stimulation, umami, saltiness, and sweetness, and the taste items measured as the "aftertaste" are bitterness, astringency, and umami richness. In other words, "umami" is the umami of the first taste, and "umami richness" as used in this invention is the umami of the aftertaste.

When raising poultry with the poultry feed of the present invention, there is no need to change the feeding method (time, frequency, amount, etc.) and all can be the same as the standard method, but in order to obtain better meat quality, raising for at least 14 days is necessary. In addition, since broilers grow rapidly, the effect of improving their meat quality can be obtained by raising them for 14 days, but depending on the type of poultry, etc., they can be raised with the poultry feed of the present invention for a rearing period longer than 14 days, for example, 21 days or more, more preferably 28 days or more, and most preferably 35 days or more. In this way, the edible meat obtained from poultry raised with the poultry feed of the present invention has improved meat quality.

The present invention is described in detail below, but is not limited thereto.

(1) Preparation of chicken feed The "basic feed" fed to chickens was either "Hina Feed Master", "Yousu Master", or "Nakasu Master" (all products of Chubu Feed Co., Ltd.) depending on the chickens' age in weeks. The "3% D-psicose-added feed" was prepared by adding 3 parts by mass of D-psicose dissolved in 10 ml of water to 100 parts by mass of the basic feed and mixing in a food mixer. Specifically, "Hina Feed Master" was used for the 3 weeks of the acclimation period, "Yousu Master" was used for the first 2 weeks of the main rearing period, a 1:1 mixture of "Yousu Master" and "Nakasu Master" was used from the 3rd week of the main rearing period, and "Nakasu Master" (all products of Chubu Feed Co., Ltd.) was used as the "basic feed" from the 25th day of the main rearing period. A "3% D-psicose-added feed" or a "control feed" without added D-psicose was prepared and used.

(2) Breeding of chickens Twelve male chunky chickens (chickens) for meat were used as the feeding subjects, divided into two groups (six chickens per group). During the first week of the acclimation period, the room temperature was 23°C and the temperature in the rearing chamber was 30°C, and during the next week, the room temperature was 23°C and the temperature in the rearing chamber was 24°C. The rearing space was an open space, and the environment was such that individual rearing was not performed. The lights were on 24 hours a day. The main rearing period was five weeks after the end of the acclimation period, and the chickens were individually reared in a rearing room set at an indoor temperature of 25°C. Food and water were freely available and were changed once a day. The lights were on 24 hours a day. The food intake was measured every morning, and the body weight was measured once a week.

(3) Processing of chickens After 18:00 on the last day of the rearing period, the chickens were fasted and dissected at 9:00 the next morning. For meat quality evaluation, no anesthetics were used, and the chickens were shocked with an electric shock device (homemade), after which dissection was performed. Blood was collected from the heart, and the plasma obtained after centrifugation was frozen (-30°C) until analysis. The chickens were then immersed in warm water to remove feathers, and breast meat, thigh meat, and liver were collected using a dissection scalpel. The collected tissues and organs were weighed, frozen using dry ice, and kept frozen (-30°C) until analysis. Small pieces of liver and thigh meat were frozen using dry ice and kept at -80°C until analysis. In addition, some of the organs and tissues were fixed with 10% neutral buffered formalin solution.

(4) Analysis of collected samples First, biochemical tests were performed using plasma. The analysis items were the glucose, neutral fat or total cholesterol concentration in plasma, the water, glycogen, neutral fat or cholesterol content in the liver, and the water, glycogen, neutral fat or cholesterol content in skeletal muscle (thigh meat). The lipid content was analyzed by extracting total lipids by the Folch method and quantitatively analyzing them using a commercially available kit manufactured by Wako Pure Chemical Industries, Ltd., and the glycogen content was analyzed by hydrolyzing the glucose produced by hydrolysis in a hot alkaline solution and quantifying it using a commercially available kit manufactured by Wako Pure Chemical Industries, Ltd.

In addition to analyzing the nutritional components (crude protein, crude fat, ash, moisture), the thigh and breast meat were also analyzed for fatty acid composition by gas chromatography, physical properties (breaking strength, moisture retention), and taste sensor analysis (umami, bitterness, sweetness, sourness, saltiness, astringency, astringency stimulation, umami richness). In order to eliminate bias, the taste sensor analysis was requested to the Laboratory of Food Functional Safety at the Kitasato University School of Veterinary Medicine, with the sample names concealed.

For nutritional analysis, thigh and breast meat were minced and crude protein was measured using the Kjeldahl method (nitrogen-to-protein conversion factor was set at 6.25), crude fat was measured using the Soxhlet extraction method with petroleum ether, ash was measured using the heat carbonization method (530°C, 24 hours), and moisture was measured using the heating method (105°C, 24 hours).

A rheometer (CR-100, Sun Scientific) was used to analyze the breaking strength, and the samples used in the rheometer were prepared by cooking each piece of meat (putting it in a sealable bag and heating it in 70°C water for 60 minutes) and then forming it with a knife into a cube with sides of approximately 10 mm. An attachment for breaking analysis was attached to the tip of the rheometer, and the maximum load (N) and the slope up to the load point (elasticity index, N/mm) were calculated. A block of meat was used to analyze the moisture retention rate, and the evaluation was based on the amount of moisture released by heating (the amount of moisture released after putting it in a sealable bag and heating it in 70°C water for 60 minutes) and the amount of moisture released by centrifugation (the amount of moisture released when the meat is wrapped in filter paper and centrifuged at 2000 x g for 30 minutes).

For the evaluation using the taste sensor, four times the amount of distilled water was added to minced breast or thigh meat, which was then further minced, and the filtrate obtained by filtering the supernatant after centrifugation was used as the measurement sample. The measurement items (taste) were umami, bitterness, sweetness, sourness, saltiness, astringency, astringency stimulation, umami richness, and sweetness, and were evaluated using a taste recognition device TS-5000Z (manufactured by Intelligent Sensor Technology Co., Ltd.).

(5) Statistical Analysis All analytical values are shown as the mean ± standard error (n = 6). Statistical analysis was performed using Excel statistics, and the difference between the "control group" and the "D-psicose-fed group" was determined to be significant when p < 0.05 by Student's st-test analysis. In the table of results below, if there is a significant difference, the numerical value is recorded, and if there is no significant difference, NS is recorded.

(6) Results (a) Weight Gain and Food Intake The results for weight gain and food intake are shown in Table 1. There was no difference between the two groups in the average food intake over 35 days, but the body weight at dissection was significantly lower in the D-psicose-fed group compared to the control group. There was a tendency for body weight during the rearing process to be lower over time in the D-psicose-fed group, but no significant difference was observed between the two groups. As for muscle weight, the actual weight of both breast and thigh meat was significantly lower in the D-psicose-fed group, but there was no significant difference in relative weight between the two groups.

(a) Evaluation of components in plasma, liver and thigh meat The results of the component concentrations and contents in plasma, liver and thigh meat are shown in Table 2. No significant differences were observed between the groups for the glucose, triglyceride and total cholesterol concentrations in plasma. In addition, no significant differences were observed between the groups for the moisture, glycogen, triglyceride and cholesterol contents in the liver and muscle (thigh meat).

(c) Evaluation of nutritional components of thigh and breast meat The composition of thigh and breast meat (crude protein, crude fat, ash, moisture) is shown in Table 4. No significant difference was observed between the two groups in the nutritional components of the thigh meat. The protein content of the breast meat was significantly higher in the D-psicose-fed group, but no significant difference was observed between the two groups in the contents of other components.

(d) Evaluation of physical properties of thigh and breast meat The results of the physical properties (breaking strength, heat water release rate, and centrifugation water release rate) of thigh and breast meat are shown in Table 5. No significant difference was observed between the two groups in the maximum load point in the breaking strength analysis, but a tendency was observed for both breast and thigh meat to be lower in the D-psicose-fed group (0.05<P≦0.1). Similar results were obtained for the elasticity index (an index indicating the gravity acting on the sample when penetrating 1 mm into the sample). On the other hand, no significant difference was observed between the two groups in the moisture rate released or desorbed by centrifugation or heating for both thigh and breast meat.

(E) Taste sensor evaluation The results of measuring the response values of umami, bitterness, off-flavor, sweetness, sourness, saltiness, astringency, astringency stimulation, and umami richness by the taste sensor for breast meat and thigh meat are shown in Figures 1 and 2. In breast meat, the response value of umami richness was high in the D-psicose-fed group, which was about 1.0 point higher than the control group. In thigh meat, the response values of umami, bitterness, and astringency were low in the D-psicose-fed group. It is said that a difference of 1 point in the measured value by the taste sensor means that the taste substances in the sample differ by about 20%, and this difference is a difference that can be sensed by the human tongue. On the other hand, even if a statistical difference is observed, if the difference is less than 1 point, the difference cannot be confirmed by the actual human tongue. Therefore, it is considered that there is almost no difference in taste between the thigh meat and the control group.

As described above, by feeding poultry feed containing D-psicose of the present invention, it is possible to obtain tender, tasty meat with an improved protein content in the breast and tender meat in the thigh, without reducing the moisture-retaining ability of the poultry meat.

Claims (3)

A poultry feed for improving the tenderness of poultry meat or enhancing the richness of its flavor, comprising 0.3 to 3.0% by mass of D-psicose. A method for improving the tenderness of poultry meat, comprising feeding poultry feed containing 0.3 to 3.0% by mass of D-psicose to poultry for two weeks or more. A method for enhancing the richness and umami of poultry meat, comprising feeding poultry feed containing 0.3 to 3.0% by mass of D-psicose to poultry for 2 weeks or more..