This research was financially supported by the earmarked fund for Jiangsu Natural Science Fund (BK20170185), Project from Jiangsu Fisheries Administrator (Y2017-30), National Natural Science Foundation of China (NFSC31801575), China Agricultures Research System (CARS-45-26), national first-class discipline program of Food Science and Technology (JUFSTR20180201), and Yi Tong-Jiangsu Postdoctoral Program.

1. Sample preparation
<ol>
	<li>Thaw frozen sturgeon meat under flowing water below 20 &#176;C. Then, clean, skin off and cut the fish into cubes (2 cm &#215; 2 cm &#215; 1.5 cm). 
	NOTE: Raw material could be fresh or frozen sturgeon meat.</li>
	<li>Mix fish cubes with 6-12% (w/v) salt solution at a rate of 1:1 (fish cube mass to solution volume), at 10 &#176;C for 1-3 h.</li>
	<li>Put the marinated fish cubes onto a stainless-steel gridding plate and dry fish cubes at 40-60 &#176;C for about 6-10 h by hot air, o...

<ol>
	<li>Riebroy, S., Benjakul, S., Visessanguan, W., Tanaka, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Changes+during+fermentation+and+properties+of+som-fug+produced+from+different+marine+fish.">Changes during fermentation and properties of som-fug produced from different marine fish.</a> Journal of Food Processing and Preservation. 31 (6), 751-770 (2007).</li><li>Xu, Y., Xia, W., Yang, F., Jinmoon, K., Nie, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+fermentation+temperature+on+the+microbial+and+physicochemical+properties+of+silver+carp+sausages+inoculated+with+Pediococcus+pentosaceus.">Effect of fermentation temperature on the microbial and physicochemical properties of silver carp sausages inoculated with Pediococcus pentosaceus.</a> Food Chemistry. 118 (3), 512-518 (2010).</li><li>Cano-Garcia, L., Flores, M., Belloch, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+characterization+and+aromatic+potential+of+Debaryomyces+hansenii+strains+isolated+from+naturally+fermented+sausages.">Molecular characterization and aromatic potential of Debaryomyces hansenii strains isolated from naturally fermented sausages.</a> Food Research International. 52 (1), 42-49 (2013).</li><li>Chen, Q., Liu, Q., Sun, Q., Kong, B., Xiong, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flavour+formation+from+hydrolysis+of+pork+sarcoplasmic+protein+extract+by+a+unique+LAB+culture+isolated+from+Harbin+dry+sausage.">Flavour formation from hydrolysis of pork sarcoplasmic protein extract by a unique LAB culture isolated from Harbin dry sausage.</a> Meat Science. 100, 110-117 (2015).</li><li>Saithong, P., Panthavee, W., Boonyaratanakornkit, M., Sikkhamondhol, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+a+starter+culture+of+lactic+acid+bacteria+in+plaa-som,+a+Thai+fermented+fish.">Use of a starter culture of lactic acid bacteria in plaa-som, a Thai fermented fish.</a> Journal of Bioscience &amp; Bioengineering. 110 (5), 553-557 (2010).</li><li>Zeng, X., Xia, W., Jiang, Q., Guan, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biochemical+and+Sensory+Characteristics+of+Whole+Carp+Inoculated+With+Autochthonous+Starter+Cultures.">Biochemical and Sensory Characteristics of Whole Carp Inoculated With Autochthonous Starter Cultures.</a> Journal of Aquatic Food Product Technology. 24 (1), 52-67 (2015).</li><li>Casaburi, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biochemical+and+sensory+characteristics+of+traditional+fermented+sausages+of+Vallo+di+Diano+(Southern+Italy)+as+affected+by+the+use+of+starter+cultures.">Biochemical and sensory characteristics of traditional fermented sausages of Vallo di Diano (Southern Italy) as affected by the use of starter cultures.</a> Meat Science. 76 (2), 295-307 (2007).</li><li>Gao, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+autochthonous+starter+cultures+on+the+volatile+flavour+compounds+of+Chinese+traditional+fermented+fish+(Suan+yu).">Effect of autochthonous starter cultures on the volatile flavour compounds of Chinese traditional fermented fish (Suan yu).</a> International Journal of Food Science and Technology. 51 (7), 1630-1637 (2016).</li><li>Zeng, X. F., Xia, W. S., Jiang, Q. X., Xu, Y. S., Fan, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Contribution+of+Mixed+Starter+Cultures+to+Flavor+Profile+of+Suanyu+-+A+Traditional+Chinese+Low-Salt+Fermented+Whole+Fish.">Contribution of Mixed Starter Cultures to Flavor Profile of Suanyu - A Traditional Chinese Low-Salt Fermented Whole Fish.</a> Journal of Food Processing and Preservation. 41 (5), 15 (2017).</li><li>Anihouvi, V. B., Sakyi-Dawson, E., Ayernor, G. S., Hounhouigan, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microbiological+changes+in+naturally+fermented+cassava+fish+(Pseudotolithus+sp.)+for+lanhouin+production.">Microbiological changes in naturally fermented cassava fish (Pseudotolithus sp.) for lanhouin production.</a> International Journal of Food Microbiology. 116 (2), 287-291 (2007).</li><li>Corral, S., Salvador, A., Flores, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Salt+reduction+in+slow+fermented+sausages+affects+the+generation+of+aroma+active+compounds.">Salt reduction in slow fermented sausages affects the generation of aroma active compounds.</a> Meat Science. 93 (3), 776-785 (2013).</li><li>Wang, W., Xia, W., Pei, G., Xu, Y., Jiang, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Proteolysis+during+fermentation+of+Suanyu+as+a+traditional+fermented+fish+product+of+China.">Proteolysis during fermentation of Suanyu as a traditional fermented fish product of China.</a> International Journal of Food Properties. 20 (90), 29-38 (2017).</li><li>Coventry, M. J., Hickey, M. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+spices+and+manganese+on+meat+starter+culture+activity.">The effect of spices and manganese on meat starter culture activity.</a> Meat Science. 33 (3), 391-399 (1993).</li><li>Zhu, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+study+on+quality+characteristics+of+pickled+and+fermented+sturgeon+(Acipenser+sinensis)+meat+in+retort+cooking.">Comparative study on quality characteristics of pickled and fermented sturgeon (Acipenser sinensis) meat in retort cooking.</a> International Journal of Food Science &amp; Technology. , (2019).</li><li>Mendonca, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamics+of+the+yeast+flora+in+artisanal+country+style+and+industrial;dry+cured+sausage+(yeast+in+fermented+sausage).">Dynamics of the yeast flora in artisanal country style and industrial;dry cured sausage (yeast in fermented sausage).</a> Food Control. 29 (1), 143-148 (2013).</li><li>Zeng, X. F., Xia, W. S., Jiang, Q. X., Yang, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+autochthonous+starter+cultures+on+microbiological+and+physico-chemical+characteristics+of+Suan+yu,+a+traditional+Chinese+low+salt+fermented+fish.">Effect of autochthonous starter cultures on microbiological and physico-chemical characteristics of Suan yu, a traditional Chinese low salt fermented fish.</a> Food Control. 33 (2), 344-351 (2013).</li><li>Gao, P., Jiang, Q., Xu, Y., Xia, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Esterase+activities+of+autochthonous+starter+cultures+to+increase+volatile+flavor+compounds+in+Chinese+traditional+fermented+fish+(Suan+yu).">Esterase activities of autochthonous starter cultures to increase volatile flavor compounds in Chinese traditional fermented fish (Suan yu).</a> International Journal of Food Properties. 20 (1), 663-672 (2017).</li><li>Wahyuni, S., Holilah, , Asranudin, , Noviyanti, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estimation+of+shelf+life+of+wikau+maombo+brownies+cake+using+Accelerated+Shelf+Life+Testing+(ASLT)+method+with+Arrhenius+model.">Estimation of shelf life of wikau maombo brownies cake using Accelerated Shelf Life Testing (ASLT) method with Arrhenius model.</a> IOP Conference Series Earth and Environmental Science. 122 (1), 12-22 (2018).</li><li>Zeng, X. F., Xia, W. S., Jiang, Q. X., Yang, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chemical+and+microbial+properties+of+Chinese+traditional+low-salt+fermented+whole+fish+product+Suan+yu.">Chemical and microbial properties of Chinese traditional low-salt fermented whole fish product Suan yu.</a> Food Control. 30 (2), 590-595 (2013).</li><li>Yu, D., Jiang, Q., Xu, Y., Xia, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+shelf+life+extension+of+refrigerated+grass+carp+(Ctenopharyngodon+idellus)+fillets+by+chitosan+coating+combined+with+glycerol+monolaurate.">The shelf life extension of refrigerated grass carp (Ctenopharyngodon idellus) fillets by chitosan coating combined with glycerol monolaurate.</a> International Journal of Biological Macromolecules. 101, 448-454 (2017).</li><li>Czerner, M., Tomas, M. C., Yeannes, M. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ripening+of+salted+anchovy+(Engraulis+anchoita):+development+of+lipid+oxidation,+colour+and+other+sensorial+characteristics.">Ripening of salted anchovy (Engraulis anchoita): development of lipid oxidation, colour and other sensorial characteristics.</a> Journal of the Science of Food and Agriculture. 91 (4), 609-615 (2011).</li></ol>

In this study, a new technique for the production of high-quality fermented fish product with wine aroma and tests for sensory properties are provided. The key processes of this technique are marinating, drying, fermentation and sterilization. In the marinating process, the salt concentration, the temperature and the time all affect the textural properties of the fish. The hardness and chewiness of the product increase gradually with the increase of salt concentration (0-12%, w/v) and the prolongation of marinating time ...

Current commercial marinated fish product in China has the problem of heavy salty taste, insufficient wine aroma, poor elasticity and pale color, which decreases the acceptability to consumers. Therefore, a new technique for a high-quality fish meat product with wine aroma needs to be created and optimized.
In recent years, application of modern fermentation techniques in meat and fish has attracted attention from more and more researchers1,2,3,4. By inoculation of starter cultures into meat and fish, food safety has been enhanced, the processing time has been shortened; and the product sensory properties have been modified. Saithong et al.5 isolated lactobacillus bacteria (LAB) from natural plaa-som and used this LAB as a starter culture, which induced high acidity and suppressed pathogenic bacteria. Zeng et al.6 reported that inoculation with the autochthonous starter cultures reduced fermentation time and improved the sensory properties of samples. Casaburi et al.7 claimed that the use of microbial starter cultures influence the development of aroma in fermented meats. In these starter cultures, S. cerevisiae could produce wine aroma by alcoholic fermentation and could also give the product other improved organoleptic qualities. Therefore, S. cerevisiae is a suitable starter culture for wine-aroma products8,9,10 and wine-aroma fish product could be made by S. cerevisiae.
In the process of making wine-aroma fish product, the texture of meat and fish could be affected by salt content, water content, pH, protein denaturation, etc. Therefore, marinating, drying, fermentation and sterilization could all influence the texture characteristics. The formation of flavor and taste is complicated and is mainly affected by marinating and fermentation, because it is highly related to hydrolysis of carbohydrates, proteins and lipids, and mild lipid oxidation11,12. It could also be affected by addition of spices13. For development of color, Maillard reaction occurs which is involved in the process of fermentation and sterilization10.
This article could provide technical support for the industrialization of fermented fish product with wine aroma, which is of great significance to the development of the fish processing industry. This technique could improve taste of product by increased proteolysis (more free amino acids and TCA-soluble peptides), modify flavor mainly by alcohols (ethanol, 1-octen-3-ol, 2-methyl-1-propanol and 3-methyl-1-butanol), esters (ethyl acetate) and aldehydes (nonanal, 3-methylbutanal and benzaldehyde), increase mouthfeel by higher hardness, springiness, gumminess and chewiness, and give more attractive russet color by and a bright surface14. It also gives consumers convenience because the product can be stored at room temperature. As described by other previous studies15,16,17, fermentation with S. cerevisiae has also been proved to significantly improve organoleptic qualities in other meat or fish products.
It is worth noting that the introduced protocol could also be applied in other species of fish, such as grass carp, silver carp, black carp, bighead carp, cod, salmon, etc. For high quality of fish products, fish without processing should be used, such as fresh fish, fish in ice or frozen fish stored for less than 1 year. Besides, since mild lipid oxidation could enhance flavor while extensive lipid oxidation brings unpleasant flavor, fish with less fat is preferred or skimmed fish is recommended.

<table>
	<tbody>
		<tr>
			<td>2,4,6-trimethylpyridine</td>
			<td>Tokyo Chemical Industry Co., Ltd.</td>
			<td>Purity 98%</td>
			<td></td>
		</tr>
		<tr>
			<td>Colorimeter</td>
			<td>Hunterlab</td>
			<td>UltraScan Pro1166</td>
			<td></td>
		</tr>
		<tr>
			<td>DB-WAX column</td>
			<td>Agilent</td>
			<td>30 m &#215; 0.25 mm &#215; 0.25&#956;m</td>
			<td></td>
		</tr>
		<tr>
			<td>Digital pH meter</td>
			<td>Mettler toledo Instrument (Shanghai) Co., Ltd.</td>
			<td>DELTA-320</td>
			<td></td>
		</tr>
		<tr>
			<td>Drying oven</td>
			<td>Shanghai Yiheng Scientific Instrument Co., Ltd.</td>
			<td>DHG-9070A</td>
			<td></td>
		</tr>
		<tr>
			<td>Frozen sturgeon</td>
			<td>Huada Marine Industry Group Co., Ltd</td>
			<td>-</td>
			<td></td>
		</tr>
		<tr>
			<td>Gas chromatograph-mass spectrometer</td>
			<td>Thermo Fisher Scientific</td>
			<td>TSQ Quantum XLS</td>
			<td></td>
		</tr>
		<tr>
			<td>Humidities incubator</td>
			<td>Shanghai Yiheng Scientific Instrument Co., Ltd.</td>
			<td>LHS-250HC-II</td>
			<td></td>
		</tr>
		<tr>
			<td>Saccharomyces cerevisiae</td>
			<td>Angel Yeast Co., Ltd</td>
			<td>-</td>
			<td></td>
		</tr>
		<tr>
			<td>Spices</td>
			<td>Auchan Supermarket</td>
			<td>-</td>
			<td></td>
		</tr>
		<tr>
			<td>Sterilization pot</td>
			<td>Longqiang Machinery Technology Co., Ltd.</td>
			<td>RHS-03-700</td>
			<td></td>
		</tr>
		<tr>
			<td>Supelco</td>
			<td>Sigma</td>
			<td>65&#956;m, PDMS/DVB</td>
			<td></td>
		</tr>
		<tr>
			<td>Texture analyzer</td>
			<td>Stable Micro Systems, Ltd.</td>
			<td>TA-XT2i</td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum package machine</td>
			<td>Quanzhou Yiminxin Electromechanical Co., Ltd.</td>
			<td>YMX-958-10L</td>
			<td></td>
		</tr>
	</tbody>
</table>

preparation of high-quality fermented fish product

This protocol provides a method for preparation of industrialized fermented fish product with sturgeon (Aquilaria sinensis) meat product. The procedures were: (1) pretreatment of farmed sturgeon including decapitation, evisceration, skinning-off, cleaning and cutting; (2) marinating fish cubes in 6-12% (w/v) salt solution (1:1, fish cube mass to solution volume); (3) drying fish cubes to a water content of 50-60% by hot air (40-60 &#176;C) or by vacuum; (4) fermentation involving inoculating fish cubes with 0.4-1.6% (w/w) S. cerevisiae in flavor solution to fish cubes and fermenting at 25-35 &#176;C for 6-10 h; (5) sealing fish cubes in vacuum packages with marinating and fermenting solutions; (6) sterilizing at 115-121 &#176;C for 10-20 min. The sturgeon meat product prepared by this method has delicious taste which is mellow and thick, has various types and large amounts of volatile flavor compounds such as alcohols and esters which could mask musty and unpleasant odor from fish, has moderate salt content but good texture properties such as high springiness, gumminess and chewiness, and has bright russet color and attractive appearance. This new technique could also be applied in the processing of other fish to provide convenient fish snack foods which could be stored at room temperature. It is appropriate for both marine and freshwater fish.

The suitable salt concentration, marinating time and temperature make the product&#8217;s textural quality better. The best marinating conditions were as follows: the salt concentration of 8% in the marinating solution; marinating time of 2 h; and marinating temperature of 10 &#176;C. See Figure 1.
In drying process, the final moisture content and drying temperature could influence the texture and sensory quality. The best drying conditions were as follows: moistu...

Watch this Scientific Journal Video about Preparation of High-Quality Fermented Fish Product at JoVE.com

Preparation of High-Quality Fermented Fish Product

The goal of the protocol is to provide an industrialized fish fermentation technique based on inoculation of Saccharomyces cerevisiae.

This protocol provides a method for preparation of industrialized fermented fish product with sturgeon (Aquilaria sinensis) meat product. The procedures ...

This procedure produces a high-quality of fermented fish product with wine aroma, and could be applied in industry production. This technique gives the fish product an attractive appearance, unique flavor, delicious taste, and good texture properties. And this product can be stored at room temperature for at least one year.To begin this procedure, thaw, clean, and skin frozen sturgeon meat as outlined in the text protocol. Cut the fish into cubes. Next, mix the fish cubes with six to 12%salt solution at a ratio of one-to-one at 10 degrees Celsius for one to three hours.Then, put the marinated fish cubes onto a stainless steel grating plate and dry them with hot air at a temperature between 40 and 60 degrees Celsius for six to 10 hours. To prepare the spice liquid, mix spices including 1.2 units of scallions, one unit of ginger, 0.6 units of star anise, 0.6 units of fennel, 0.3 units of green tea, and 0.3 units of pepper with 40 units of water. Boil for half an hour, and collect the filtrate.To prepare the flavor solution, mix spices liquid, yellow wine, white wine, cane sugar, monosodium glutamate, and vinegar in the mass fractions shown here. After this, mix the dried fish cubes with the flavor solution, inoculating 0.4 to 1.6%saccharomyces cerevisiae at a ratio of one-to-one. Seal the mixture in a container, and ferment at a temperature between 25 and 35 degrees Celsius, for six to 10 hours.Place the fermented fish cubes into a vacuum package with marinating and fermenting solutions and seal the vacuum package with a vacuum strength of 0.085 megapascals, a sealing time of 3.6 seconds, and a cooling time of 5.5 seconds. Then sterilize the packed fish cubes using a sterilization temperature between 115 and 121 degrees Celsius for 10 to 20 minutes. In this study, high quality fermented fish product is prepared.Using a suitable salt concentration, marinating time, and temperature makes the products textural quality better. The best marinating conditions are seemed to be a salt concentration of 8%And the marinating solution, a marinating time of two hours. And a marinating temperature of 10 degrees Celsius.In the drying process, the final moisture content and drying temperature can influence the texture and sensor quality. The best drying conditions are seemed to be a moisture content of the dried fish cubes of 55%and drying temperature of 50 degrees Celsius. In the fermentation process, the addition of saccharomyces cerevisiae, the temperature, and the time all effect the taste, flavor, color, and texture properties of fish.The successful fermented fish has high scores for taste, flavor, color, and texture, resulting in harmonious taste, fermentative fragrance, winey, russet color, bright surface, caramel, and al dente texture. The failed fish product has the low scores for taste, flavor, color, and texture resulting the poor taste, bitterness, sourness, fishiness, pale color, rough surface, coarse mouthfeel, and deteriorated texture. The suitable sterilization and intensity is seemed to be 4.5 minutes.And a suitable sterilization temperature is seemed to be 121 degrees Celsius. The storage considerations are then calculated and determined as outlined in the text protocol. And the prediction for the shelf life is 264 days at 25 degrees Celsius or 205 days at 35 degrees Celsius.When performing this procedure, it is important to note that both fermentation and the sterilization steps are vital to the success of this technique. After learning this procedure, it can be used in fermentation of other fish species. In future, fermentation with other strains could be investigated.Such as lactobacillus, staphylococcus, et cetera. regions, make sure to take precautions when sterilizing fish products, as extremely high temperature could cause harm.

preparation-of-high-quality-fermented-fish-product

Research

JoVE Journal

Biochemistry

10.0K 조회수.  Jiangnan University. 이 절차는 와인 향을 가진 발효 생선 제품의 고품질을 생산하고, 산업 생산에 적용 될 수있다. 이 기술은 생선 제품에 매력적인 외관, 독특한 맛, 맛있는 맛, 좋은 질감 특성을 제공합니다. 그리고 이 제품은 실온에서 1년 이상 보관할 수 있습니다.이 절차를 시작하려면 텍스트 프로토콜에 설명된 대로 해동, 깨끗하고 피부냉동 철갑상어 고기. 물고기를 큐브로 자른다. 다?...