不同颜色PE 食品包装袋对马铃薯绿化和龙葵素含量的影响

研究不同颜色包装袋对马铃薯绿化和龙葵素含量的影响。结果表明：在自然光照条件下,马铃薯表皮绿化速度和程度以及龙葵素含量随贮藏时间延长而迅速增加;不同颜色包装袋包装可有效控制马铃薯绿化及龙葵素含量的增加,其中绿色和黑色包装袋对其控制效果较优,马铃薯贮藏45d,黑色和绿色包装袋包装的马铃薯叶绿素含量比对照分别降低53.97% 和65.89%,龙葵素含量分别降低80.71% 和75.89%。     

马铃薯及其有害成分龙葵素(二)

马铃薯块茎中含有龙葵素。龙葵素又叫茄素,是一种有毒物质,人、畜食用过量均能引起中毒。龙葵素中毒的潜伏期为数十分钟至数小时,轻者恶心,呕吐,腹泻,瞳孔放大,头晕,舌、咽麻痒,胃痛,耳鸣;严重的丧失知觉、麻痹、休克,若抢救不及时会造成死亡。 马铃薯块茎中龙葵素含量安全标准为20mg/100g,一般成熟的正常马铃薯中,龙葵素含量为7—10mg/100mg,食用是安全的。但马铃薯块茎生芽和经日光曝晒,薯皮上出现了绿色到深绿色区,会产生大量龙葵素,含量可增至500mg/100g,远远超过了安全标准,因此,不宜大量食用生芽和绿色马铃薯。 龙葵素溶于水,遇醋酸易分解。食用马铃薯时,先把芽、芽眼、变绿和溃烂部分削去或挖     

有一些蔬菜易中毒应怎样预防

[1]在发芽或青绿色皮的马铃薯中,含有有毒物质龙葵素。100克马铃薯芽约含龙葵素420～703毫克,人若一次摄入约200毫克龙葵素使会发生中毒。轻者咽部发痒,胸口闷热、发烧、恶心、呕吐、腹泻,严重者可出现呼吸困难,甚至心脏麻痹。因此食用前应将发芽马铃薯的     

不同处理对马铃薯货架期内保鲜效果的影响

为探究不同处理方式对马铃薯的货架保鲜效果,以市售马铃薯为原料,将乙醇熏蒸、海藻酸钠涂膜及壳聚糖涂膜处理后的马铃薯置于600 lux、25℃的人工气候箱中模拟货架期条件储藏,对贮藏期间马铃薯的失重率、发芽指数、色泽、叶绿素含量、硬度等品质指标及龙葵素含量进行测定分析,结合主成分分析综合评价马铃薯在不同处理下的保鲜效果。结果表明：经过9d的贮藏,与对照组相比,3种处理均有效延缓了马铃薯的绿变及萌芽的产生;海藻酸钠涂膜及壳聚糖涂膜处理均可显著抑制马铃薯贮藏期间的表观色泽变化、失重率、硬度的下降及块茎和皮层中龙葵素的合成;乙醇熏蒸处理加剧了马铃薯贮藏期间的失重率及硬度下降;对马铃薯货架期的保鲜效果中以海藻酸钠涂膜处理最具有优越性,壳聚糖涂膜处理次之,乙醇熏蒸处理的保鲜效果相对较差。该研究可为马铃薯的产后贮藏保鲜提供理论参考。     

马铃薯中马来酰肼的迁移安全性研究

目的 考察马来酰肼在马铃薯块茎及芽中的分布、迁移规律。方法 离子排斥色谱-紫外法检测马铃薯中马来酰肼含量,并进行方法验证;用该方法对马来酰肼在马铃薯中的迁移情况进行考察：用马来酰肼溶液分别处理马铃薯块茎和马铃薯芽,考察马来酰肼在不同浓度下向马铃薯块茎中的迁移情况及马来酰肼在马铃薯块茎和芽之间的迁移情况。结果 马铃薯块茎在0.04~8.00 mmol/L马来酰肼中浸泡24 h后,马铃薯中马来酰肼的含量随着马来酰肼浓度的增加而增加,当浓度增大到5.95 mmol/L时,马来酰肼在马铃薯中的迁移率趋于稳定,在1.47%左右;当浸药浓度大于5.95 mmol/L时,马来酰肼在马铃薯中的残留量超过GB 2763—2016《食品安全国家标准 食品中农药最大残留限量》所规定的50 mg/kg的残留限量要求。马铃薯块茎在5.04 mmol/L马来酰肼溶液中浸泡24 h后,距离表皮越近,迁移的马来酰肼含量越高,马来酰肼在不同马铃薯品种中的迁移能力有差异。用5 mmol/L马来酰肼溶液分别处理发芽期马铃薯块茎和马铃薯芽叶,发现块茎中的马来酰肼会定向向芽叶中迁移并累积,而芽叶中的马来酰肼不会从芽向块茎迁移。结论 该离子排斥紫外方法准确、灵敏,适用于马铃薯块茎及芽叶中马来酰肼含量的测定,马来酰肼向马铃薯块茎中的迁移率总体较低。     

酸浸草鱼腌制工艺研究

目的：改善腌鱼的口感，缩短腌制时间，减低盐含量，提高腌制品安全性；方法：以草鱼为原料，通过感官评定，比较几种不同酸（食醋、柠檬酸、乳酸）的处理效果；并以细菌总数，挥发性盐基氮为主要指标，研究腌制液浓度、液固比（W：V）、腌制时间、加酸量等对产品品质的影响；结果：食醋的处理效果优于其它2种酸；液固比为2：1、腌制时间2h、腌制液浓度10％、食醋添加量3％时，产品具有良好口感，盐含量为8％，细菌总数少于20000CFU／g，TBVN指数小于60mg／100g.符合低盐安全的要求。     

马铃薯片常压油炸工艺优化研究

对影响常压油炸马铃薯片品质的工艺参数进行了优化研究。结果表明,在柠檬酸溶液浓度为0.10%～0.25%、预干燥时间为10～40min和油炸温度为170～200℃的范围内,以薯片的丙烯酰胺含量、含油量和脆度为指标,常压油炸薯片的最佳工艺条件为:薯片切片采用柠檬酸溶液浓度为0.20%的柠檬酸水溶液浸泡后,于85℃预干燥30min,最后用180℃恒温油炸至熟。     

热浸处理对加工芒果催熟损失的影响研究

为降低加工用原料芒果病害损失率,满足食品工业生产安全、高效、易操作的要求,研究采用不同温度、不同时间的热水浸泡处理台农1号芒果,分析微生物指标、发病指数、烂果率/烂果减少率等指标,研究热浸处理对芒果加工原料催熟后损失率的影响。结果表明:50℃10～30min、55℃5～15min、60℃3～5min的热浸处理可以显著地降低采后加工用原料芒果表面微生物的含量;抑制芒果催熟过程中病斑面积及数量的增大与增加,降低芒果催熟过程中的烂果率,达到降低芒果原料损失率的目的。其中,60℃3min的热浸处理方法,使烂果减少率达到了75%,不仅达到了通常商业热浸处理条件降低损失率的效果,而且显著地减少了热浸处理的时间,提高了处理效率。     

棉油皂脚复浸回收中性油的工艺

棉油皂脚中中性油含量视不同工艺而异。间歇法生产工艺得到的棉油皂脚中性油含量一般在30％～40％，有的高达40％～50％。而“棉油皂脚复浸回收中性油工艺”可使中性油含量降到3％～5％，复浸后的皂脚经处理后可作为化工原料出售或进一步深加工。     

不同预加工方式对马铃薯片中丙烯酰胺的影响

研究不同预加工方式对油炸马铃薯片中丙烯酰胺生成的影响,进而探讨一种可有效抑制马铃薯片中丙烯酰胺含量的方法。将马铃薯片在不同温度（120℃ ～200℃）及不同时间（0 ～30 min）下进行油炸处理,通过品质指标及丙烯酰胺含量的变化趋势确定最佳油炸时间及温度,利用高效液相色谱法测定经热烫和添加剂浸泡后马铃薯片中丙烯酰胺的含量,并计算丙烯酰胺抑制率。在未进行预处理条件下,随着油炸时间及油炸温度的增大,质量损失率、色差呈整体上升趋势,水分活度、水分含量及还原糖含量呈整体下降的趋势,丙烯酰胺含量呈先上升后下降的趋势;在油炸前进行不同预处理对马铃薯片中的丙烯酰胺具有显著抑制作用,90℃热烫处理协同5 g/L半胱氨酸溶液浸泡处理10 min对马铃薯片中丙烯酰胺的抑制率达到了100%。因此,热烫协同半胱氨酸溶液浸泡处理是一种可有效抑制马铃薯片中丙烯酰胺含量的方法。     

The hygienic evaluation of potato treated with the preparation Polikar made from the byproducts of soda manufacture

It has been shown that Polycar prepared from sodium carbonate byproducts, intended for the treatment of potatoes before its storage, makes for an increase in solanine content, and a decrease in the level of ascorbic acid in potato. Such potato produces a toxic effect on the rat body. A conclusion has been made that Polycar could not be used as an agent for potato treatment.     

盐渍海蜇脱铝研究及安全食用建议

目的采用不同弱酸浸泡盐渍海蜇脱铝,探讨海蜇产品铝含量超标安全风险,研究降低海蜇产品铝含量的食用方法。方法采用高纯水、盐酸、冰醋酸、柠檬酸以及食用醋5种不同溶液分别浸泡不同铝含量的盐渍海蜇除去盐渍海蜇中的铝,分析实验前后铝含量及观察实验前后样品感官变化。结果水浸泡法对降低海蜇中残留铝的效果有限;盐酸与柠檬酸溶液有较好的脱铝效果,但脱铝后海蜇样品韧性变差,品质下降;冰醋酸与食用醋溶液有较好的脱铝效果,且脱铝后海蜇样品有光泽,柔软饱满、有弹性,冰醋酸浓度为0.1 mol/L浸泡4h时和食用醋浓度为体积比1/9浸泡4 h,是最佳的浸泡浓度及时间,脱铝后海蜇样品铝含量符合SC/T3210-2001《盐渍海蜇皮和盐渍海蜇头》中明矾含量使用规定。结论建议生产者在生产即食海蜇时增加冰醋酸溶液浸泡工序,消费者在食用盐渍海蜇时进行食用醋溶液浸泡,以降低铝残留危害。     

UV-C处理抑制马铃薯贮藏期发芽及相关机理研究

为提高马铃薯的食用安全性和贮藏品质,本实验研究了短波紫外线(ultraviolet C,UV-C)处理对马铃薯贮藏过程中发芽品质的影响。采用10 kJ/m² UV-C对马铃薯进行一次处理(贮藏前),二次处理(贮藏前及中期),并测定发芽率、还原糖、苯丙氨酸解氨酶、多酚、赤霉素、α-茄碱等指标。结果表明,UV-C处理能够有效抑制马铃薯贮藏过程中的发芽,同时延缓赤霉素和α-茄碱的上升。二次处理组贮藏至90 d时,薯皮和肉质部分的α-茄碱含量仅为对照组的71.09%、65.75%;105 d时发芽率为68.78%,还原糖含量为0.40%,失重率为4.71%,贮藏品质均优于对照组和一次处理组。综上所述,当处理剂量和方式适宜时,UV-C可在马铃薯发芽控制及品质保持方面获得良好效果,其中二次处理更具优势。     

EFFECTS ON THE ALKALOID CONTENT OF POTATOES GROWN FROM SEEDS SUBJECTED TO LOW-DOSE GAMMA IRRADIATION

SUMMARY— Effects of low dose gamma irradiation of seeds on alkaloid content, proximate composition and yield of the potato tubers were studied. Increase in yield with irradiation of seeds was inconclusive. Changes in proximate composition of Russet potatoes grown from tubers irradiated at 1,500 rads were found to be insignificant. Varietal differences in solanine content were more pronounced than those due to gamma irradiation. In all cases the solanine content in potatoes grown from irradiated seeds was found to be far below the toxic level for human beings.     

Effect of Pretreatments and Air‐Frying,a Novel Technology,on Acrylamide Generation in Fried Potatoes

This paper investigated the effect of air‐frying technology, in combination with a pretreatment based of soaking the samples in different chemical agent solutions (citric acid, glycine, calcium lactate, sodium chloride, or nicotinic acid [vitamin B3]), on the generation of acrylamide in fried potatoes. The influence of reducing sugars on the development of surface's color was also analyzed. The experiments were conducted at 180 °C by means of air‐frying and deep‐oil‐frying, as a reference technology. Based on the evolution of color crust with frying time, it could be concluded that the rate of Maillard reaction decreased as the initial reducing sugars content increased in the raw material, and was also lower for deep‐oil‐frying than for air‐frying regardless of pretreatments applied. Air‐frying reduced acrylamide content by about 90% compared with conventional deep‐oil‐frying without being necessary the application of a pretreatment. However, deep‐oil fried potatoes pretreated with solutions of nicotinic acid, citric acid, glycine at 1%, and NaCl at 2% presented much lower acrylamide levels (up to 80% to 90% reduction) than nonpretreated samples.     

酸处理对烤马铃薯条品质的影响

为了改善烤马铃薯条品质，选用不同质量分数的柠檬酸、苹果酸、醋酸溶液预处理马铃薯条，通过测定烤后马铃薯条的质构、水分分布等品质指标以探究酸处理对烤马铃薯条的作用规律。结果表明，酸浸泡处理减缓了烤制对马铃薯细胞的破坏，烤马铃薯条的孔隙减少，硬度升高。质量分数越高，烤马铃薯条失重率越大（P<0.05），水分流失越严重，2%醋酸处理5 h失重率高达（57.83±1.49）%；随浸泡时间的延长，烤马铃薯条硬度和剪切力均增加（P<0.05），浸泡5 h时微观结构最为致密；柠檬酸和苹果酸浸泡有助于烤马铃薯条产生花香味和蘑菇味。     

Content of anthocyanins and glycoalkaloids in blue‐fleshed potatoes and changes in the content of α‐solanine and α‐chaconine during manufacture of fried and dried products

In the last ten or so years, potatoes with purple or blue‐flesh and derivative products, for example chips, have appeared on the European markets. The interest in this raw material and these products is increasing among both producers and consumers searching for novel and attractive choices. The anthocyanin content of the analysed potato varieties differed; a higher content of these pigments was determined in Blaue Elise var. potatoes. In blue‐flesh varieties, the prevailing anthocyanins were acylated glycosides: petunidin and malvidin. The production process of French fries, chips and puree caused a decrease in the content of glycoalkaloids in semi‐products and finished products, compared to the raw material. The greatest losses of α‐chaconine and α‐solanine were observed after tuber peeling (ca. 70%) and after frying (ca. 90%). French fries contained 3%, chips 16% and puree 17% of the initial amount of total glycoalkaloids. The losses of α‐chaconine and α‐solanine in the analysed semi‐products and finished products were at the same level, regardless of the processing technology applied.     

Industrially processed vacuum-packed peeled Kennebec potatoes: process optimization, sensory evaluation, and consumer response

To optimize the processing and storage of Kennebec potatoes for sale in peeled, vacuum-packed ready-to-cook form, we studied the effects of blanching, various anti-browning solutions, and storage temperature. Unblanched potatoes pretreated with a mixture of 1% ascorbic acid and 0.5% citric acid, and stored at 2 °C, were found to have a shelf life of at least 1 mo without browning. Potatoes so treated differed sensorially from fresh potatoes, but were well received by consumers. PRACTICAL APPLICATION: The process described here maintains the characteristics of fresh potato with all the amenities of a processed product.     

油炸马铃薯片中丙烯酰胺形成的影响因素的研究

丙烯酰胺是富含碳水化合物和氨基酸的食品经高温加热发生美拉德反应而产生的,但有关影响丙烯酰胺形成因素的研究却较少。探讨了油炸温度、原料中还原糖和氨基酸含量、鲜薯切片浸泡液的柠檬酸浓度、油炸前薯片的水分含量及抗氧化剂和油的使用时间对丙烯酰胺形成的影响。结果表明:原料中还原糖和氨基酸含量越高,产品中生成的丙烯酰胺就越多;油炸温度越高,产品中丙烯酰胺含量也相应越高;浸泡液柠檬酸浓度越大,产品中丙烯酰胺含量越低;而随着半成品中含水量的降低,产品中的丙烯酰胺含量也逐渐减少;在油中添加不同浓度的BHT和TBHQ以及采用使用时间不同的油,对加工出来的薯片之间丙烯酰胺含量没有显著的影响。     

Microbial growth and the effects of mild acidification and preservatives in refrigerated sweet potato puree

Refrigerated sweet potato puree is a convenient form of sweet potato that can be used as an ingredient in formulated foods. The microbiology of refrigerated sweet potato puree during storage for up to 5 weeks was evaluated. Because the puree was made by comminuting steam-cooked sweet potatoes before refrigeration, no naturally occurring vegetative bacterial cells were detected during a 4-week period of refrigerated storage at 4 degrees C. However, if postprocessing microbial contamination of the puree were to occur, contaminating microorganisms such as Listeria monocytogenes could grow during refrigerated storage. The effects of acidification or the addition of potassium sorbate and sodium benzoate on a population of L. monocytogenes inoculated into refrigerated (4 degrees C) sweet potato puree were determined. Inoculation of the refrigerated puree with L. monocytogenes at 10(6) CFU/ml resulted in a 3-log increase after 3 weeks storage of nonsupplemented puree. Supplementation of the sweet potato puree with 0.06% (wt/vol) sorbic acid or benzoic acid plus mild acidification of the sweet potato puree with citric acid to pH 4.2 prevented growth of L. monocytogenes during storage at 4 degrees C.