USE OF A UTENSIL FOR TABLE USE OR COOKING USE

Abstract: It is the object of the present invention to provide utensils for table use or cooking use, which can easily improve the taste of food and drink and make them tasty without using particular energy in a short time. The utensils for table use or cooking use according to the present invention have their surface coated with a film of titanium oxide; when they are exposed to sunrays, an electric light or the like, electrons and positive holes are formed on the film of titanium oxide on the surface thereof according to photocatalytic reaction, whose strong oxidation-reaction decomposes residual chlorine and organic compounds dissolved in water to remove the odor of chlorine and the odor of mold and makes clusters of water in food and drink small to improve the taste of food and drink and to make them tasty.

Description: The present invention relates to use of a utensil for table use or cooking use, which has a function to improve the taste of food and drink and to make them tasty. We have often known from experience that, for example, in regard to alcoholic drinks, while a cheap and low-grade whiskey has a rough and strong taste in the mouth, a high-grade one has a soft and mild taste in the mouth. As a result of the investigation of these both whiskeys according to nuclear magnetic resonance (NMR), it was showed that a high-grade whiskey showed a curve of a thin and sharp peak of water in the chart obtained, and clusters of water in the whiskey had become smaller in comparison with the same of a cheap whiskey. It is considered generally that the taste of a whiskey is improved as the clusters of water become smaller (Nippon Nogeikagaku Kaishi, Vol. 60, No. 3, pp. 191-197 (1986)). The clusters of water are defined as associated materials of water molecules such as (H 2 O)n according to hydrogen bonds. Incidentally, various attempts have been performed hitherto with a view to improving the taste of water and alcoholic drinks in a short time without taking much time like an aging process. In the methods deemed to be effective up to now, a method for applying ultrasound onto beverages and drinks including alcohols and a method for irradiating far infrared rays onto them by using far infrared rays ceramics are cited as instances (Hiroo Takashima, Kogyo Chosakai, K Books 66, Easy Far Infrared Rays Engineering, p. 111 (1988)). However, the former method needs an ultrasound generator and has problems in its complexity and energy cost; on the other hand, the latter method is convenient, but since the energy of far infrared rays discharged is small, it has a problem in its effect. In addition, both methods have a defect in taking much time. Besides, the taste of drinking water are deteriorated by various organic compounds existing in city water such as the residual components of chlorine (residual chlorine) used for disinfecting city water, the odor of chlorine produced by a reaction between the residual chlorine and organic materials in water and the odor of mold incapable of being removed according to an activated sludge method. The present invention has been accomplished from the above viewpoint, and, it is an object of the present invention to provide use of a utensil for table use or cooking use, which can easily improve the taste of food and drink and make them tasty without using particular energy in a short time. In addition, it is another object of the present invention to provide use of a utensil for table use or cooking use, which can easily improve the taste of drinking water, food and drink and make them tasty in a short time only by using light energy such as sunrays and an electric light. Further, it is still another object of the present invention to provide use of a utensil for tableware or cooking utensils, which can maintain a function and effect to improve the taste of drinking water, food and drink and to make them tasty semipermanently by using a film of titanium oxide having an advantage being durable, non-toxic and innoxious for health. EP-A-489914 discloses a utensil for cooking or for table use having on a surface which comes into contact with the food or drink a coating consisting of a film of titanium oxide. In this reference the purpose of the film is to provide a film having an attractive surface colour. The film of titanium oxide used in the reference is of rutile-type titanium oxide. According to this invention there is provided the use of a utensil for table or cooking use as claimed in claim 1 herein. The utensils for table use or cooking used in the present invention have their surface coated with a film of titanium oxide; when they are exposed to sunrays, an electric light or the like, electrons and positive holes are formed on the film of titanium oxide on the surface thereof, whose oxidation-reaction decomposes residual chlorine to remove the odor of chlorine and the odor of mold in water and makes clusters of water in food and drink small to improve the taste of drinking water, food and drink, and make them tasty. The present invention uses utensils for table use or cooking use, having at least the surface of their side coming into contact with food and drink or cooking materials coated with a film of titanium oxide. When food and drink or cooking materials are put into the utensils for table use or cooking use according to the present invention, or the utensils according to the present invention (e.g., straw) are put into a vessel containing food and drink or cooking materials, electrons and positive holes are formed on the film of titanium oxide on the surface of the utensils according to photocatalytic reaction due to being exposed to sunrays, an electric light or the like, whose strong oxidation-reaction decomposes residual chlorine to remove the odor of chlorine and the odor of mold in water and makes clusters of water small to improve drinking water, food and drink, and make them tasty. Examples of the utensils for table use or cooking use used in the present invention include various vessels such as a cup, glass, tumbler, jug, pitcher, bottle, thermos bottle, bowl, pan, kettle, pot, jug, pad, sake bottle, teacup, rice bowl and glass vessel of a mixer, and stick-like articles such as a spoon, pair of chopsticks, skewer, ladle, egg beater, toothpick, muddler and straw. As materials of the utensils for table use or cooking use used the present invention are used those having a required strength on which a film of titanium oxide can be formed; examples thereof include concrete, glass, plastics, ceramics, metals or the like. The application of a film of titanium oxide the present invention is generally the whole surface of an utensil; in vessel-like utensils, however, only the surface of the inside coming into contact with food and drink or cooking materials may be coated with the film. The utensils may be transparent or non-transparent; however, light permeates through utensils from the outside and can be irradiated onto the film of titanium oxide in transparent utensils, which is preferable in case of forming a film of titanium oxide on the inside of the utensils such as vessels and a straw. The forms of the utensils for table use or cooking use may be square-pillar-like, column-like, ball-like, conic, gourd-shaped or rugby-ball-shaped. They may be also closed, may have also a lid or not, and in addition may be round-tube-like or square-tube-like A film of titanium oxide on the surface of the utensils may be prepared by making a titania sol from titanium alkoxide obtained according to a reaction between titanium tetrachloride and alcohol, applying it onto the surface of the utensils for table use or cooking use according to dip coating, spin coating, coating, spray coating or the like and then calcinating it, or the surface of titanium utensils for table use or cooking use may be heated and oxidized with a gas flame to make titanium oxide. In addition, it may be prepared by coating the surface of the utensils for table use or cooking use with a suspension of ultrafine particles of titanium oxide according to dip coating, spin coating, coating, spray coating or the like, and then calcinating it. Moreover, the surface of the utensils for table use or cooking use may be coated with a film of titanium oxide according to known CVD, PVD, spattering, flame spray coating or the like. If water, beverages such as Japanese sake or cooking materials are put into the thus obtained utensils for table use or cooking use, electrons and positive holes are formed on the film of titanium oxide on the surface of the utensils due to being exposed to sunrays, an electric light or the like, whose reaction makes clusters of water coming into contact with the film of titanium oxide on the surface of the utensils small to improve the taste of beverages and the like and make them soft and mild in a short time. In addition, if the article used in the present invention such as a spoon, pair of chopsticks or muddler is put into a vessel containing water, beverages such as Japanese sake or cooking materials, the taste of the beverages and the like is improved and they become soft and mild similarly due to being exposed to sunrays, an electric light or the like. If stirring is also performed in this case against the utensils used in the present invention, the taste of the beverages and the like is more improved. As sources of light to be employed in the present invention can be exemplified the light of sunrays, incandescent lamp, fluorescent lamp, halogen lamp, xenon lamp, mercury lamp and UV lamp preferably. As light to be irradiated may be used light containing a lot of light with a short wavelength like ultraviolet rays; in addition, light with a long wavelength like visible light rays can be employed satisfactorily. If metals of the platinum group such as platinum, rhodium and ruthenium, and/or iron, silver or the like are further deposited on the film of titanium oxide on said surface, the function and effect of improving the taste of beverages and the like are more increased. Besides, the film of titanium oxide may be further coated with a film of platinum or the like. Fig. 1 shows the results of NMR measurement obtained by putting city water into a cup as an embodiment of the present invention, irradiating light thereon and then performing NMR measurement, and the results of NMR measurement obtained by putting city water into an ordinary heat-resistant glass cup, irradiating light thereon and then performing NMR measurement. Explanation of the Symbols A: Curve according to the NMR measurement of the water put into a cup as an embodiment of the present invention. B: Curve according to the NMR measurement of the water put into an ordinary cup. Preferable examples of the present invention will be described in detail hereunder. Example 1 City water was put into a heat-resistant glass cup according to the present invention obtained by coating the surface with a titania sol liquid prepared from titanium alkoxide according to dip coating and calcinating it at 550 °C to coat the surface of the inside thereof with a film of titanium oxide, and light was irradiated thereon, and then the water was measured according to nuclear magnetic resonance (NMR). For comparison, city water was put into an ordinary heat-resistant glass cup coated with no film of titanium oxide, and light was irradiated thereon, and then the water was measured according to NMR. As the results are shown in Fig. 1, the curve A in the case of using the cup according to the present invention has a thin and sharp peak of water and shows clusters of water being become smaller compared with the curve B in the case of using the ordinary cup. As a result of applying the water to a sensory test actually, the water put into the cup used in the present invention had neither the odor of mold nor the odor of chlorine and was improved in the taste as soft, mild and tasty as the one of mineral water compared with the water put into the ordinary cup. Example 2 A muddler used in the present invention, which is obtained by coating the surface thereof with a suspension of ultrafine particles of titanium oxide according to spray coating and calcinating it at 600 °C to coat the surface thereof with a film of titanium oxide, was put into a glass containing a cheap whiskey diluted with water and it was stirred under the light of an electric lamp for several minutes; as a result, the taste of the whiskey was improved and the strong taste thereof in the mouth was removed and its taste became soft and mild like a high-grade whiskey. Besides, the odor of chlorine due to residual chlorine in the whiskey diluted with water was removed and it was delicious and tasty. Moreover, the same effect could be obtained when the muddler of the present invention was used for other beverages such as Japanese sake, wine and shochu. Example 3 Beer was sampled slowly to apply to a sensory test by using a glass straw used in the present invention obtained by coating the surface thereof with a titania sol liquid prepared from titanium alkoxide according to dip coating and calcinating it at 500°C to coat the surface thereof with a film of titanium oxide; as a result, the taste of the beer was improved and the bitterness thereof was decreased and the taste of it became soft and mild. The same effect was obtained when other articles used in the present invention were used for beer. As described above, the articles used in the present invention are utensils for table use or cooking use, whose surface is coated with a film of titanium oxide; electrons and positive holes are formed on the film of titanium oxide on the surface of the utensils due to being exposed to sunrays, an electric light or the like, whose oxidation-reaction makes clusters of water contained in food and drink, such as alcoholic drinks (Japanese sake, beer, cocktails, fruit wine and the like), milk, soft drinks and other food and drink, or other cooking materials such as soy sauce, small to improve the taste of food and drink and to make them tasty. In addition, since the utensils for table use or cooking use used in the present invention employ only light energy, they have an effect capable of improving easily the taste of food and drink and making them tasty without using particular energy in a short time. Besides, since residual chlorine, the odor of chlorine and the odor of mold can be decomposed, the taste of water itself can be improved. Moreover, titanium oxide to be used in the present invention is generally used also for coatings, cosmetics and tooth powder and has an advantage being durable, non-toxic and innoxious for health. Accordingly, tee utensils for table use of cooking use used in the present invention can be used semipermanently and the function and effect said above can be maintained semipermanently so far as being exposed to light.

Claims: Use of a utensil for table or cooking use, said utensil having at least on the surface of a side coming into contact with food and drink or cooking materials, a coating consisting of a film of titanium oxide characterised in that said titanium oxide has a photocatalytic action when exposed to light radiation to improve the taste quality of food and drink. The use as claimed in claim 1, wherein the film of anatase-type titanium oxide is formed by coating the surface thereof with a titania sol liquid prepared from titanium alkoxide, and heating it at a temperature less than 600°C. The use as claimed in claim 1, wherein the film of anatase-type titanium oxide is formed by coating the surface thereof with a suspension of ultrafine particles of titanium oxide, and heating it at a temperature less than 600°C.

Inventors: KATO SHIGEKAZU, MINOWA KIMIKO, TAODA HIROKO, YOKOI HIROAKI, KATO, SHIGEKAZU, MINOWA, KIMIKO, TAODA, HIROKO, YOKOI, HIROAKI, TAODA, HIROKO, 4-301, INOKOSHI-JUTAKU
Applicants: AIWA CO, KATO MFG CORP LTD, AIWA CO., LTD., KATO MANUFACTURING CORPORATION LIMITED
Application year: 1995
Main classification: A47J36
IPC codes: C02F1, A47G21, A47J41, B01J35, A47G19, A47J36, B65D23, A47J43