阅读说明：本技术 食用燕窝及其处理方法 (Edible bird's nest and its processing method ) 是由 白洄銖 陳政順 于 2017-01-19 设计创作，主要内容包括：本发明提供了一种处理用于制作燕窝汤的可食用燕窝的方法。方法包括去除燕窝基质中的固体杂质；活化燕窝基质中的糖蛋白,去除燕窝的微生物污染,冷冻干燥燕窝以去除其中的水分,并保持燕窝的微孔。(The invention provides a method for processing edible bird's nest used for making bird's nest soup. The method comprises removing solid impurities in nidus Collocaliae matrix; activating glycoprotein in the bird's nest matrix, removing microbial contamination of the bird's nest, freeze-drying the bird's nest to remove moisture therefrom, and maintaining the micro-pores of the bird's nest.)

1. A method for processing edible bird's nest for preparing bird's nest soup, comprising the steps of:

removing solid impurities in the cubilose matrix;

activating glycoproteins in the bird's nest matrix;

removing microbial contamination from the bird's nest; and

freeze drying the bird's nest to remove water while retaining micropores within the bird's nest.

2. A method as claimed in claim 1 wherein solid impurities are removed simultaneously when the bird's nest is immersed in water.

3. A method as claimed in claim 2 wherein the bird's nest is soaked in water for 3-24 hours, swelling the bird's nest matrix to 5-20 times its original size.

4. A method as claimed in claim 2 or 3 wherein the bird's nest is soaked at 1-20 ℃.

5. A method as claimed in any preceding claim wherein the glycoprotein is activated by heating and freezing the bird's nest for a plurality of cycles.

6. A method as claimed in any preceding claim, wherein the microbial contamination is removed by autoclaving the bird's nest.

7. A method as claimed in any preceding claim wherein one or more food additives are incorporated into the bird's nest matrix.

8. A method according to claim 4, wherein the additive is an extract of red date, eaglewood, longan, Cordyceps sinensis, lemon grass, ginseng, collagen and tissue.

9. A method as claimed in any preceding claim, wherein the autoclaved bird's nest is frozen on a mould.

10. A process as claimed in any one of the preceding claims wherein the solid impurities are removed by hand picking.

11. A method as claimed in any preceding claim wherein filamentous regions of the raw bird's nest are used.

12. A dried edible bird's nest prepared by the method of any one of the preceding claims.

13. An edible bird's nest contains 250-1250mg of activated sialic acid and/or glycoprotein per kilogram of the bird's nest.

Technical Field

The present invention relates to Edible Bird's Nest (EBN). More particularly, the present invention relates to a method of pre-treating raw edible bird's nest and a clean, cooked and dried edible bird's nest prepared therefrom, wherein the dried edible bird's nest has a high content of activated glycoproteins, sialic acid and a high water absorption capacity.

Background

Edible bird's nest is derived from bird's nest of swiftlet, especially javanica, which, during the breeding season, secretes bird's nest paste from its pair of sublingual glands to build up the bird's nest after stimulation by reproductive hormones. Edible bird's nest is considered to be nutritive and contains active substances that may have anticancer, anti-aging and immune enhancing functions. Edible bird's nest is therefore considered a valuable food, particularly in Chinese culture, due to its nutritional value and rarity.

The bird's nest generally has a shallow cup shape and is composed of interwoven filaments of bird's nest mud secretions. Raw bird's nest can be collected from a cave or a house of swiftlet. However, swiftlet houses are the preferred source of choice because they promote the persistence of swiftlet habitat and bird nest supply. Raw bird's nests typically contain large amounts of solid impurities, microbial contamination, and nitrous and nitrate content. Thus, it is common practice in the industry to pre-treat raw bird nests prior to sale to consumers.

The commercially treated raw bird's nest is dried and cleaned to reduce microorganisms or other contaminants. However, such bird's nests are typically treated with bleach and other chemicals to clean the bird's nest and give it a beautiful appearance. The chemical treatment changes the properties of the bird's nest and reduces the nutritional value and natural aroma of the bird's nest. Nevertheless, raw bird's nest, whether cooked, washed or not, requires a prolonged soaking and boiling time to dissolve the glycoprotein or to release its active compound, sialic acid. It is also difficult to control the cooking time of the bird's nest, which may result in loss of nutritional value due to overcooking or loss of digestion and absorption by the human body due to undissolved glycoprotein.

In order to solve the inconvenience of cooking raw edible bird's nest, an instant edible bird's nest, namely an instant edible bird's nest filled in a bottle, is developed. Dietary additives may be added to enhance the taste experience of the consumer. The instant edible bird's nest is prepared by mixing cleaned bird's nest, water and additives in a glass container, and then heating for sterilization and cooking. In order to prolong the service life of the product, the addition of preservatives is inevitable. Since the product is in liquid form inside the glass container, it can be a problem to handle it. The consumer cannot customize the flavor of the instant bird's nest to his or her own taste.

Another type of instant bird's nest has been invented, wherein the bird's nest is in dry form and is ready to eat after 10-30 minutes of mixing with boiling water, known as instant bird's nest. Chinese patent (CN 102715507) discloses a method for preparing instant edible bird's nest. The method comprises soaking clean raw nidus Collocaliae in water to soften and swell it; stewing the expanded edible bird's nest; cooling and molding the cooked cubilose; and freeze-drying the formed nidus Collocaliae. Despite the rapid serving time, the product has a comminuted bird's nest in order to increase the surface area for water absorption. The nutritional value of such bird's nest is low because the cooking has degraded or dissolved out most of the nutrients into the water.

To overcome these disadvantages, it is desirable to develop an improved method of treating raw bird's nests, and to provide edible bird's nests with a higher content of easily soluble glycoproteins, which retain natural bird's nest aroma, have customizable flavors, and can be supplied in a shorter time. The present invention provides a solution to these problems.

Disclosure of Invention

It is an object of the present invention to provide an improved method for pre-treating raw edible bird's nest for preparing a cooked and dried edible bird's nest that can be eaten immediately as a snack or softened in water and eaten in a short period of time.

It is another object of the present invention to prepare dried edible bird's nest with increased amounts of activated glycoprotein and/or sialic acid and other nutrients so that the bird's nest can be easily absorbed by the digestive system after consumption.

It is yet another object of the present invention to increase the water absorption capacity of dry edible bird's nest so that the bird's nest can be softened in water in a shorter period of time.

It is another object of the present invention to maintain the natural aroma of edible bird's nest even after washing and processing the edible bird's nest.

Another object of the present invention is to provide a dry edible bird's nest which can be formed into various shapes and sizes.

It is another object of the present invention to provide dry edible bird's nest with customizable flavor by adding edible additives.

At least some or all of the above objects may be achieved by the present invention, embodiments of which describe a method of processing edible bird's nests for preparing bird's nest soup, comprising the steps of: removing solid impurities in the cubilose matrix; activating glycoproteins in the bird's nest matrix; removing microbial contamination in the bird's nest; and freeze drying the bird's nest to remove moisture while preserving the micropores within the bird's nest.

In a preferred embodiment of the invention, when the bird's nest is soaked in water, solid impurities are removed simultaneously. Preferably, the bird's nest is soaked in water for 3-24 hours, so that the bird's nest matrix is expanded to 5-20 times of the original size. Preferably, the nidus Collocaliae is soaked at 1-20 deg.C.

In another preferred embodiment of the invention, the glycoprotein is activated by heating, freezing and performing multiple cycles.

In another preferred embodiment of the invention, the microbial contamination of the bird's nest is removed by autoclaving/cooking.

Preferably, one or more dietary additives are incorporated into the bird's nest matrix. The additive is selected from extracts of fructus Jujubae, lignum Aquilariae Resinatum, arillus longan, Cordyceps, herba Cymbopogonis Citrari, Ginseng radix, collagen protein and tissue.

Another embodiment of the invention is a dried edible bird's nest made by the method described in any of the preceding.

The preferred embodiments of the invention include the novel features and combinations of parts hereinafter fully described and illustrated in the accompanying drawings and particularly pointed out in the appended claims. It will be understood that various changes in the details may be effected therein by one skilled in the art without departing from the scope of the invention or sacrificing any of the advantages of the present invention.

Detailed Description

The present invention relates to Edible Bird's Nest (EBN). More particularly, the present invention relates to a method for pre-treating raw edible bird's nest and clean, cooked and dried edible bird's nest prepared therefrom, wherein the dried edible bird's nest has more activated glycoproteins, sialic acid and stronger water absorption capacity.

Hereinafter, the present invention will be described according to preferred embodiments thereof with reference to the accompanying specification and drawings. It should be understood, however, that the description is limited to the preferred embodiments of the invention only for the purpose of facilitating the discussion of the invention, and it is envisioned that those skilled in the art may devise various modifications without departing from the scope of the appended claims.

The invention discloses a method for processing edible bird's nest for preparing the bird's nest, which comprises the following steps: removing solid impurities in the cubilose matrix; activating glycoproteins in the bird's nest matrix; removing microbial contamination in the bird's nest; and freeze drying the bird's nest to remove moisture while preserving the micropores within the bird's nest.

As used herein, the term "edible bird's nest" or "bird's nest" refers to swiftlet's nest, particularly javanica, whether raw or cooked, clean or unclean, and dry or moist. As used herein, the term "raw bird's nest" refers to raw and untreated bird's nests collected from a cave, swiftlet's house, or any collectible place. Raw bird nests are preferably harvested from the houses of swiftlets, as they are lower in contamination and easier to control than cavities. In one embodiment of the invention, the entire raw bird's nest is treated. In a preferred embodiment of the invention, however, only the filamentous regions of raw bird's nests are used and treated to provide treated bird's nests with a uniform and homogenous appearance and texture. Since the filamentous region usually contains minimal contamination, it is also advantageous to use this region only.

According to a preferred embodiment of the invention, solid impurities are removed from the bird's nest matrix, wherein the raw bird's nests are first soaked and expanded. Raw bird's nest is immersed in excess water to soften and expand the volume of the raw bird's nest. Preferably, the immersion of raw bird's nest is at a temperature of 1 ℃ to 20 ℃, more preferably 2 ℃ to 4 ℃. Soaking at lower temperatures deactivates the microbial activity, thereby minimizing microbial proliferation and preventing further microbial contamination of the bird's nest. The nidus Collocaliae can be soaked for 3-72 hr, preferably 12 hr. Typically, the soaked bird's nest may expand 5-20 times its original size. Typically, but not always, a soaking time of 12 hours may expand to a size of 10 times. It is desirable not to soak for a long time because the bird's nest may be too soft to handle, cook and shape, and may affect the quality of the bird's nest.

In another preferred embodiment of the present invention, the method further comprises the step of incorporating an edible additive into the soaked bird's nest. The additive can be selected from, but not limited to, extracts from plants and animals such as fructus Jujubae, lignum Aquilariae Resinatum, arillus longan, radix Ginseng, Cordyceps, rhizoma Zingiberis recens, herba Cymbopogonis Citrari, collagen protein, animal tissue, etc., or combinations thereof. Other additives may also be used to improve the flavor and color of the bird's nest. The additive is added into water during soaking. The particles of the additive are incorporated into the matrix of the bird's nest due to the swelling of the bird's nest caused by the absorption of moisture. The amount of additive incorporated into the bird's nest matrix is determined by the concentration of the additive in the soaking water.

As described in the preferred embodiment of the present invention, the steepwater may be changed multiple times throughout the steeping period. The nitrite/nitrate granules dissolve out into the immersion water by diffusion, so that the nitrite/nitrate content of the bird's nest is reduced or eliminated. The steepwater is preferably changed at least 2 times to bring the nitrite/nitrate content down to a safe level. In case the additive is added to the soaking water, the additive may only be added to the last replacement soaking water, since the diffusion of nitrite/nitrate particles may be affected by the incorporation of the additive and also the waste of additive may be minimized.

After soaking, the swollen bird's nest is taken out of the soaked water, and then solid impurities are removed. Preferably, the solid impurities are removed by a manual picking process, no chemicals are used in the process, and possible physicochemical property changes of the bird's nest can be avoided. In addition, other methods may be used to remove solid impurities from the bird's nest, such as sonication and the like. However, a method of further immersing the bird's nest in a chemical liquid to remove solid impurities is not suggested because the previously incorporated additives may be dissolved out and the physicochemical properties of the bird's nest may be changed.

As described in the preferred embodiment of the present invention, the cleaned bird's nest is subjected to a plurality of cycles of the heating-freezing process. The cleaned bird's nest is first heated with steam for 10-120 minutes and then frozen at-5 ℃ to-80 ℃, more preferably at-10 ℃ to-30 ℃ for 12 hours. Multiple heating and freezing cycles are performed to release and loosen the glycoproteins and/or sialic acid and other nutrients in the bird's nest. The glycoprotein and/or sialic acid will be activated in situ and will dissolve in the water retained by the bird's nest without dissolving out of the bird's nest matrix. Therefore, to prevent the dissolution of the glycoprotein and/or sialic acid and additives, it is not recommended to heat the bird's nest by boiling or any heat treatment method that requires immersing the bird's nest in water. Overheating should also be prevented to avoid degradation of glycoproteins and/or sialic acid. The heat-freeze cycle is carefully controlled to prevent loss of activated glycoprotein and/or sialic acid.

Activation of glycoproteins and/or sialic acid in the bird's nest is very important. Both of these components are generally considered to be functional or active compounds of nutrition. Usually these two ingredients are bound to the bird's nest matrix and are not readily soluble in water, although a small proportion of them occur in an activated form in natural conditions. By activating these two and other active ingredients, they become readily soluble in water and therefore readily digestible to the consumer.

In addition, in another preferred embodiment of the present invention, edible additives may also be incorporated during the heat-freezing process. The solution of the additive was added to the bird's nest, followed by heating to concentrate the amount of additive. It should be noted that the food additives may be incorporated during the steps of soaking and/or heat-freezing.

After the heat-freezing process, the bird's nest may be considered as a cooked bird's nest. Despite possible microbial contamination, a significant amount of water remains within the matrix of the cooked bird's nest. The water content contains dissolved glycoprotein, sialic acid and additives. The cooked bird's nest is autoclaved to remove microbial contamination. Preferably, the cooked bird's nest is autoclaved at 95-110 ℃ for 20-60 minutes.

According to a preferred embodiment of the present invention, the autoclaved bird's nest containing a large amount of moisture of the dissolved glycoprotein and additives is freeze-dried to remove the moisture while maintaining the micropores within the bird's nest. Preferably, the bird's nest is freeze dried on the mold. The mold may have various shapes and sizes depending on the desired configuration of the freeze-dried cubilose product. However, as long as the shape of the bird's nest can be maintained after freeze-drying, the use of a mold is not required. The shaped autoclaved bird's nest is first frozen to fix shape, size and weight, and then freeze-dried to remove moisture from the bird's nest. When the water is removed, the glycoprotein and additives remain within the matrix of the bird's nest. In particular, glycoproteins are present in an activated form, and thus, when the nidus Collocaliae is consumed, they can be easily absorbed by the human digestive system. Freeze-drying also provides dried bird's nest with high porosity and therefore high water absorption capacity.

In an exemplary embodiment of the present invention, the finished bird's nest soup may be prepared by simply softening dry bird's nests (hereinafter, treated bird's nests) in sufficient water, especially boiling water, for 5-30 minutes. The treated bird's nest has high water absorption capacity because it is easily softened due to the large number of micropores. Additional dietary additives, such as, but not limited to, sugar, salt, milk, and honey, may be added over the pre-blended additives. The softness of the edible bird's nest can be controlled by controlling the soaking time in hot water, thereby providing different tastes to consumers. In addition, the bird's nest may also be eaten in dry form as a snack. The treated bird's nest produced by the above method can maintain the natural aroma of bird's nest, which is generally known as egg white taste.

A further embodiment of the invention is a dried edible bird's nest prepared by the method described in any one of the preceding claims. The dry cubilose has high porosity, so that the dry cubilose has high water absorption capacity. Preferably, the edible bird's nest has a pore size of 10-300 μm. Dried bird's nest also contains a large amount of activated glycoproteins and sialic acid. Thus, glycoproteins and other nutrients are readily absorbed by the natural body when consumed. The dried cubilose may have various shapes and sizes depending on the desired configuration of the product. The shape may be selected from, but is not limited to, cup, sheet, heart, circle, square, and glyph.

In yet a further embodiment of the invention, the dried bird's nest may contain granules of edible additives within the matrix of the bird's nest. The additive can be selected from, but not limited to, extracts of plants and animals such as fructus Jujubae, lignum Aquilariae Resinatum, arillus longan, radix Ginseng, Cordyceps, rhizoma Zingiberis recens, herba Cymbopogonis Citrari, collagen, and animal tissue.

While the invention has been described and illustrated in detail, it is to be understood that the invention is by way of illustration and example, and not by way of limitation. The spirit and scope of the present invention are to be limited only by the terms of the appended claims.