Patent Application
20080026125
EPA and/or DHA may be mentioned as representative examples of the long-chain highly unsaturated fatty acids according to the present invention. There is no limitation on their origin. Those skilled in the art may optionally use those derived from various animals and vegetables, bacteria and algae that are commercially available. Among them, fish oil, especially condensed EPA and DHA oil (purified fish oil) derived from bonito or tuna is preferable in terms of purity and cost. The fat or oil composition of the present invention may comprise two or more kinds of the long-chain highly unsaturated fatty acids.
The oleic acid and linolic acid used in the present invention may be any one known to those skilled in the art, usually those contained in various fat or oil as a constituting fatty acid of triglyceride. They include vegetable oil such as corn oil, sunflower oil, safflower oil and wheat germ oil. Any two or more kinds of the above oil may be optionally mixed and used. Corn oil is most preferable in terms of both cost and the fatty acid composition.
The linolenic acid used in the present invention may be any one known to those skilled in the art, usually those contained in various fat or oil as a constituting fatty acid of triglyceride. They include vegetable oil such as flax seed oil, perilla oil, rape seed oil and soybean oil, flax seed oil being most preferable in terms of the fatty acid composition
There is no limitation on how to prepare the fat or oil composition according to the present invention. For example, it may be prepared by choosing one or more kinds of the above oil and appropriately mixing or blending them. Especially, the fat or oil composition prepared by mixing purified fish oil, corn oil and flax seed oil is preferable.
The weight % of EPA, DHA, oleic acid, linolic acid and linolenic acid was determined based on the weight % calculated from a percentage ratio in accordance with the ratio of chromatogram peak area that was obtained in gas-chromatograph (GLC) analysis according to Standard Methods for the Analysis of Fats, Oils and Related Materials 3.2.3-1996.
As already described, the present invention shows the advantages that the favorable taste from a sensory point of view will be kept stably for a long period of storage time by satisfying the particular fatty acid ratio. No particular antioxidant is needed to be added to the present fat or oil composition in order to obtain the above advantages. It is, however, possible to optionally add an antioxidant or oxidation inhibitor known to those skilled in the art, such as tocopherol, ester of ascorbic acid, rosemary extract, green tea extract and licorice extract; a metal chelator such as citric acid and malic acid; an emulsifier such as glycerin fatty acid esters, sucrose fatty acid esters and lecithin; and an antifoamer such as silicon oil to the fat or oil composition for the purpose of improving its stability against oxidization and heating. The antioxidant may be usually added at a ratio of 0.005˜0.2% by weight. The fat or oil composition according to the present invention may be used widely in general cooking except deep-frying.
Peroxide value (POV) may be used as an index for degree of the oxidation of fats and oils. This value is obtained by reacting hydroperoxide produced by incorporation of oxygen in the air into the fat or oil with potassium iodide, and tittering an amount of released iodine with sodium thiosulfate solution. It is expressed with a unit of milli-eqivalent per 1 kg of a sample (meq/kg). It is one of the features of the present invention that there is no clear relationship between the POV and the unfavorable taste from a sensory point of view, i.e., the off-flavor. Accordingly, the advantages of the present invention shall be evaluated by the ratio of the fatty acids comprised in the composition of the present invention and a sensory test.
The “unfavorable taste from a sensory point of view” according to the present invention means the off-flavor (fishy odor) represented by, for example, 2,4,7-decatrienal. The unfavorable taste may be evaluated according to the sensory test described in the examples and comparative examples in the present specification.
The present invention will be explained with reference to the examples and comparative examples, which should not be construed in any way to limit the scope of the present invention. The “%” in the following examples means “% by weight.”
Purified fish oil containing DHA of 26.7% and EPA of 8.3%, purified corn oil containing oleic acid of 28.8% and linolic acid of 45.5%, and purified flax seed oil containing linolenic acid of 39.8% were homogeneously blended at various ratios described in Table 1.
Purified fish oil containing DHA of 26.7% and EPA of 8.3%, purified high-oleic safflower oil containing oleic acid of 77.4%, purified safflower oil containing linolic acid of 77.3%, and purified flax seed oil containing linolenic acid of 39.8% were homogeneously blended at various ratios described in Table 1.
Each composition (10 g) was taken into a deep petri dish with 7.4 cm in inside diameter and 3.7 cm in depth, kept in an open oven at 60° C. and subjected to the sensory test to evaluate their smell. The test was done in accordance with 5-grade evaluation shown in Table 2 based on an average value of four panelists (n=4).
The results of evaluation shown in Table 3 demonstrate that the suppression of the off-flavor would not be significantly effected if the fatty acid ratio to EPA and/or DHA did not satisfy the desired requirements. Furthermore, in the case that the ratio of the long-chain highly unsaturated fatty acids was more than 7% or more of the whole fatty acids, the suppression of the off-flavor would not be significantly effected even if a total weight of oleic acid, linolic acid and linolenic acid was appropriate.
An antioxidant of green tea extract manufactured by Sankyo Lifetech co., Ltd., SUNFOOD (Yusei) was added to the fat or oil composition of Example 1 at the ratio of 0.1% under nitrogen gas at 60° C. and completely solved therein.
An antioxidant of rosemary extract manufactured by Mitsubishi Chemical Ltd., RM21B) was added to the fat or oil composition of Example 1 at the ratio of 0.01%, under nitrogen gas at 60° C. and completely solved therein.
Each composition (10 g) of Examples 3 & 4 was taken into a deep petri dish with 7.4 cm in inside diameter and 3.7 cm in depth, kept in an open oven at 60° C. and subjected to the sensory test to evaluate its smell. The test was done in accordance with 5-grade evaluation shown in Table 2 based on an average value of four panelists (n=4). As seen from the results of evaluation in Table 4, the addition of the antioxidant did not cause any significant change from Example No. 1 in the suppressing effect of the fishy odor or off-flavor, and did not deteriorate the same effect from a sensory point of view, either. But if oxidative deterioration is monitored by a chemical index, an improving effect may be expected with the addition of the antioxidant.
Purified fish oil containing DHA of 23% and EPA of 7%, purified corn oil containing oleic acid of 28.8% and linolic acid of 45.5%, and purified flax seed oil containing linolenic acid of 39.8% were homogeneously blended at various ratios described in Table 5.
Purified fish oil containing DHA of 23% and EPA of 7%, purified high-oleic safflower oil containing oleic acid of 77.4% were homogeneously blended at various ratios described in Table 5.
Each composition (10 g) of Examples A˜C and Comparative Example D was taken into a deep petri dish with 7.4 cm in inside diameter and 3.7 cm in depth, kept in an open oven at 60° C. and subjected to the sensory test to evaluate their odor. The test was done in accordance with 5-grade evaluation shown in Table 2 based on an average value of four panelists (n=4). The results of evaluation shown in Table 6 demonstrate that the suppression of the off-flavor would not be significantly effected if the fatty acid ratio of to EPA and/or DHA did not satisfy the desired requirements.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2003-193980 | Jul 2003 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP04/06368 | 5/12/2004 | WO | 00 | 1/30/2007 |
