Study On Salted Technics And Storing Technology Of Salted Lanxi Radish

Radish growing in the city of Lanxi, Zhejiang province is generally called "LanxiRadish". It is mainly processed into salted radish, which is popular as it iswhite, dilicious, fragile and tender, moderate in size, and it is helpful to digestion andstimulate the appetite. But the industry of radish has been lagged, because it could bepreserved not more than two months by exiting conserving method.This paper studied curing technology and conserving method of "Lanxi radish", It willprovide theoretical basis for prolonging the conservation span of "Lanxi radish". By usingcomposite conserving reagents and taste condifionging reagents, the conservation span ofsalted"Lanxi radish" is prolonging up to three months, which is of greate importance inpractice.This paper systematically studied the changs of quality during curing in a factory. Byexaming pH value, soluble solids, salinity, content of water and nitrite, and changes ofsensory character, it was found that the quality of salted radish under natural fermentationwas affected notably by ambient temperature. When temperatation was high, pH valuechanged quickly and maturation period was short. It was time to change pools when pHwas 3.0-3.5, after which changes to about 3.2, content of soluble solids is 7.0-7.8, salted"Lanxi radish" was mature. The changs of colour and texture were happened in the start ofsalted, nitrite reached maximum in the third or forth day. So mature salted "Lanxi radish" issafe to eat.This study is about dealing salted "Lanxi radish" with differ conserving method andresearching the changes of L^*, a^*, b^*,â–³E value, brittleness, total acid and sense qualityduring storage. The results indicated:salted radish changed to bad slowness in a lowtemperature, it should be packed with complex wrapper and avoided of light; Thecircumstance of sterilization with 2 % NaClO₂, 5 min hot steam, 30 min with 60 Celsiuswater, 1.5KG spoke. After 2 months, the effect is not salience, microbe were still growingin the pack. When 100 % O₂ was inputed in the pack, film forming on the surface ofsalted radish after 30 days, and oxygen diminished. Input 100 % CO₂ in the pack, filmforming on the surface of salted radish, and CO₂ diminished after 60 days. When 100 %N₂ in the pack, some film forming on the surface of salted radish after 90 days, and N2still in the package. Natural aseptic Phytic acid, Nisin and onion sootiness were used topreserve salted radish. The results showed: Phytic acid and Nisin contributed little inpreserving of salted radish, onion sootiness had obvious effect, the salted radish had littlechange after 90 days. 0.1% Sodium Diacetate and 0.02 % disodium dehydroacetate were used in preserving salted radish, spoilage microbe still grew in packs. 0.1% SodiumDiacetate with 0.1% benzoic acid and 0.02% disodium dehydroacetate with 0.1%benzoic acid also used in salted radish, they had remarkable antisepsis effect, no microbegrew in packs.Sodium sulfite, ZnSO₄, and L-cysteine are used to protect color. The results showed:sodium sulfite was the best way to protect color, but it could not be used in food. ZnSO₄and L-cysteine effected on color retention in a certain extent, but it was not distinct after60 days. 0.025% Na₂EDTA, 2% sodium potassium tartrate, 0.3% Sodiumpyrophosphate, and the compound of the three matters as complexing agent to combinecalcium. But they did not effect on increasing brittleness. The calcium be added in saltedradish could keep brittleness. Especially, 0.4 % calcium and 0.4 % alginate.This text protected color by using onion sootiness and onion extracts by pbs. Theresults showed: onion sootiness was useful to protect color, but the radish started tochange to yellow after 30 days. Onion Extracts by pbs could protect color, but the effectwas not distinct because of its red color, and the white mold could grow on it after 60days.The taste conditionging reagents for salted radish is important. The results showedthat the taste conditionging reagents had no gentleness flavor if we just used few flavoring.Through the orthogonal experiments, the optimum taste conditionging reagents formula isas follows: 0.06 % monosodium glutamate; 12 % or 8 % white sugar; 0.05 % mix acid;0.05 % apple vinegar; 2 % or 1% salt; 0.1% or 0.05 % phosphor acid; 0.1% acetic acid;0.1% material alcohol.Spoilage microbe is the most important factor to cause salted radish decayed. This testisolated Escierichia Coli, penicillium and four kinds of yeasts from the corrupted packingsalted radish. Differ onion extracts and preservative were used to control them. The resultsshowed: onion sootiness could restrain microbe. But volatility in onion just restrain theascending of substrate without airproof the utensil. Around the utensil volatility in onionwas litter, so microbe still growed around the substrate. It was difficult to extractavailability component which can restrain microbe from onion. Only onion extracts by pbscould restrain penicillium in four extract ways. Onion juice have little availabilitycomponent, because it's main is water. So only high concentration onion juice couldrestrict microbe. This test used three antiseptic that is used in pickle often. The resultsshowed that they could not restrain yeasts and penicillium, but they could strongly restrainEscierichia Coli. So it is difficult to restrain microbe in single way. In order to prolongkeeping quality time, many ways should unite together. Through the orthogonal experiments analysis showed:Add 0.125% benzoic acid and0.0125% disodium dehydroacetate, 0.2 % ZnSO₄ and 0.048% L-cysteine, 0.2% alginate and0.4% CaCl₂, Onion extractions, total sauce liquor=1:10 in salted radish was a good way tokeep quality, the salted radish could preservate for 3 months.Differ concentration of H₂O₂ and differ pH value 2% H₂O₂ were studied to blanchsalted radish. The results showed: more high concentration more quickly whiten the saltedradish, The yellow matter on radish disappeared quickly. Salted radish became clarity andwhite, but then the salted radish was too white, it was distortion. Meanwhile, highconcentration of H₂O₂ destroy organise of radish and radish became pliancy and lost itsbrittleness. 2%H₂O₂ blanch salted radish commendably in alkalescence condition, andeffective in acidity as well. Besides, salted radish was more reality in acidity. Thebrittleness of salted radish was little influenced in 2%H₂O₂ pH4. By using compositeconserving reagents and taste conditionging reagents, salted radish could still keep whiteabout 3 months and in 37℃for 10 days.