Research On Shape Stability For Canned Diced Tomatoes

In the process of canned diced tomatoes there were some problems, such as make loss of unstablenutrients and reduce the shape stability of diced tomatoes due to the blanching, sterilization and otherprocessing factors. Xinjiang Guannong Fruit&Antler Group Co. found that the production of canned dicedtomatoes prone to the shape instability caused by non-microbial factors during storage, most canned werelistening ruanta, deformation, and even the whole pot becomes concentrated condensed matter, hamperedthe development of the industry of canned diced tomatoes seriously. This alticle selects the tomatoes to takerawmaterial. The effects of scalding, hardening and terilization conditions on processing of canned dicedtomatoes were studied. On the basis of single factor test results, the three process parameters wereoptimized by response surface methodology. Then studied the change detection on firmness, soluble solids,total sugar, total acid, pectin content and other indicators of diced tomatoes during storage; finally studiedthe effect of the curing agent on the texture of diced tomatoes, including the relationship between pectinand hardness, the effect of pectin methlesterase and calcium chloride on tissue cells.The results showedthat:1.Using scalding to determine the optimum peeled tomatoes for hardness and sensory evaluation, theresults were as follows: the scalding temperature95℃, scalding time60s;hardness index to filter outcalcium chloride as a curing agent; The three process parameters were optimized by response surfacemethodology for improved hardness and overall sensory quality score. The results showed that the optimalprocess conditions for production of canned diced tomatoes were as follows: pectin methlesterase andcalcium chloride were added at0.4mL/kg and5g/kg, the treatment time of19min; using heat sterilizationmethods to determine the optimum sterilization for hardness, sensory evaluation and microbial indicatorsevaluated, the results is determined as follows:sterilization tempereture95℃, time15min. Under thisoptimized conditions, the quality of canned diced tomatoes was significantly improved.2.The change of hardness, TSS, total sugar, total acid content of canned diced tomatoes is variaty inearly storage, but remained in the late storage, the loss of nutritional value is small; pectin content hassignificant change during storage, TP content and NWSP content was gradually declining tred, WSPshowed growing trend in early storage and slowly in late.3.The hardness, pectin content and tissue slices of diced tomatoes by harding processed and traditionalprocessed were observed, the results as follows:the texture stability was relation with structures andcontents of pectin, there was negatively correlated between hardness and WSP content, and positivecorrelated between hardness NWSP content; pectin methlesterase and calcium chloride can significantlyincrease the hardness of diced tomatoes, due to inhibit the conversion of NWSP to WSP; the pectinmethlesterase and calcium chloride enables to inhibited collapse of cell wall and augment of cell range,maked the cells intact, tightly packed and thick cell walls. The shape and structure of canned dicedtomatoes was significantly improved.