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1.
为了找出最适于延长油炸豆腐丝货架期的热处理条件,比较3种热处理条件(105℃/10 min;105℃/20 min;120℃/10 min)下油炸豆腐丝的贮藏情况。并通过对油炸豆腐丝的感官评价、菌落总数及脂肪氧化程度(过氧化值、p H、硫代巴比妥酸值)的测定,综合对比找出最适处理条件并给出合理建议及货架期。结果表明:在37℃贮藏条件下,105℃/10 min处理的样品的菌落总数在23 d超过国标限值,比105℃/20 min处理得样品延长10 d左右,120℃/10 min处理条件严重损坏样品的品质。105℃/10 min处理的样品的货架期最长,室温(25℃)下可贮藏92 d,与其它两个处理相比,该条件既能保证产品品质,又可以延长货架期,建议食品企业选用此条件进行灭菌。  相似文献   

2.
茶多酚处理对冷藏养殖大黄鱼品质的影响   总被引:3,自引:1,他引:2  
研究了经过0.2%茶多酚浸泡的养殖大黄鱼和对照组在4℃冷藏条件下25d内品质的变化。定期分析了处理组和对照组大黄鱼样品的感官特征、微生物指标(菌落总数)和化学指标(pH、TVB-N、K值)。结果表明,在冷藏过程中茶多酚处理能延长大黄鱼货架期7~8d,在货架期终点15d时,茶多酚处理组和对照组样品的细菌总数分别为106.12CFU/g和107.45CFU/g,pH值分别为6.78和6.84,TBA值分别为0.122mg/kg和0.168mg/kg,TVB-N分别为166.6mg/kg和318.7mg/kg,K值分别为27.10%和43.72%。可见,茶多酚在大黄鱼冷藏保鲜过程中能有效地抑制细菌繁殖,并减缓脂肪氧化,从而延长了大黄鱼的货架期。  相似文献   

3.
对6株剑麻茎腐病原菌黑曲霉菌生物学特性的研究结果表明,在不同种类培养基、pH值、温度、光照等培养条件下病原菌生长速率有差异,病原菌的孢子生长的温度范围为10~44℃,最适温度为32℃,菌落生长的最适pH值为9,全光照条件下菌落生长最适,分生孢子的致死温度为60℃,50 min。  相似文献   

4.
研究了经过0.2%茶多酚浸泡的大黄鱼片和对照组在0℃冷藏条件下20d内品质变化特性。定期分析了处理组和对照组大黄鱼片样品的微生物指标(菌落总数)和理化指标(pH、MDA、K、MetMb、Mb、Caspase-3)。结果表明,冷藏过程中茶多酚处理能够降低化学指标活性,抑制微生物的生长,保持和延长鱼片保质期。因此,在0℃真空包装冷藏保鲜过程中茶多酚处理能更长时间保持大黄鱼片的良好品质。  相似文献   

5.
剑麻茎腐病菌突变株的生物学特性研究   总被引:1,自引:0,他引:1  
从感病剑麻植株中分离到了一株茎腐病茵的突变茵株,并对其形态特征和生物学特性进行了研究.与已报道的黑曲霉菌明显不同的是:该茵在PDA平板上茵丝丰富、白色、产孢速度慢,其分生孢子表面有瘤状突起.该茵茵落生长与产孢的温度范围为15 ℃~40℃,最适为35℃;菌落生长的最适pH值为9,各pH值条件下产孢无显著差异;全光照条件下茵落生长和产孢速度显著快于光暗交替和全黑暗条件.孢子萌发的温度为20℃~45℃,最适为35℃;pH值4~时,孢子萌发率最高;光照对孢子萌发没有明显的影响;分生孢子的致死温度为50℃,10min.  相似文献   

6.
以传统豆制品白干和薄百叶为材料,对贮藏过程中主要腐败微生物进行分离鉴定。利用纯培养的方法共筛选出菌落形态差别比较明显的菌株19株。对细菌菌株进行形态观察、革兰氏染色和生理生化鉴定,同时对细菌和酵母菌纯培养物提取DNA,分别进行16S rDNA和26S rDNA PCR扩增,PCR产物经测序后与NCBI中已知序列进行比对和鉴定,确定各细菌和酵母菌菌株的种属;霉菌纯培养物染色后观察孢子繁殖形态,最终确定这些菌株的种属。结果表明:白干和薄百叶中共有的优势腐败菌是溶酪葡萄球菌,枯草芽孢杆菌,约翰逊不动杆菌,戊糖片球菌;季也蒙毕赤酵母,皮状丝孢酵母;圆弧青霉和黄绿青霉。此外,白干中还有诞沫假丝酵母;薄百叶中有浅黄假单胞菌,芸苔丝孢酵母。  相似文献   

7.
武杰  朱飞  赵颖 《大豆科学》2011,30(4):697-699
五香豆于是营养丰富又极难防腐保鲜的食品,进行了利用微波杀菌真空包装技术延长五香豆干货架期的研究.将五香豆干采用耐高温蒸煮袋包装,含水量控制在65%左右,在室内常温条件下采用的频率为2450 MHz微波杀菌120~180 s,在(36±1)℃温箱培养7d后,其含菌量不高于GB2711-2003要求,感官评分远远高于对照组...  相似文献   

8.
试验以新型豆干坯子的破裂距离、破裂强度和感官评分为评价指标,评估分析大豆分离蛋白的凝胶值、破裂距离和pH对豆干坯子的质构和口感影响。在单因素试验基础上通过正交试验确定影响豆干坯子质构和口感的因素组合。结果表明:大豆分离蛋白的凝胶值为900±20 g/mm,破裂距离为23.0±0.3 mm,pH为7.6时,测得豆干坯子破裂距离为33.9 mm,破裂强度为839 g,感官评分为93,在此条件下制作的豆干坯子硬度高,脆度好,弹性适中,最适合用于硬脆型豆干的加工制作;大豆分离蛋白的凝胶值为700±20 g/mm,破裂距离为22.0±0.3 mm,pH为7.9时,测得豆干坯子破裂强度为1372g,破裂距离为28.4 mm,感官评分为91,在此条件下制作的豆干坯子弹性足,韧性好,口感偏软,最适合用于软弹型豆干的加工制作;大豆分离蛋白的凝胶值为800±20 g/mm,破裂距离为23.0±0.3 mm,pH为7.9时,测得豆干坯子破裂强度为1 105 g,破裂距离为32.8 mm,感官评分为95,在此条件下制作的豆干坯子硬度强,弹性好,有嚼劲,最适合用于硬弹型豆干的加工制作。综合考虑,硬脆型豆干坯子所需SPI最优指标为凝胶值900±20 g/mm、破裂距离23.0±0.3 mm、pH7.6;软弹型豆干坯子所需SPI最优指标为凝胶值700±20 g/mm、SPI的破裂距离为22.0±0.3 mm、pH为7.9;硬弹型豆干坯子所需SPI最优指标为凝胶值800±20 g/mm、破裂距离23.0±0.3 mm、pH 7.9。  相似文献   

9.
本文研究不同温度、不同pH条件下右旋糖酐酶的保存稳定性,并尝试加入防腐剂和稳定剂达到右旋糖酐酶酶液在常温下长期保存的目的。实验结果表明:①右旋糖酐酶在pH5.5时,温度为4—25℃下保存150h,相对酶活仍有90%以上;但当贮存温度超过30℃后,酶活在较短时间明显下降,且温度越高,酶活下降速度越快。②右旋糖酐酶在pH4—6,温度为4℃下保存一周,相对酶活仍有80%以上。③右旋糖酐酶液中添加甘油浓度达到30%时,室温下保存56天后,相对酶活仍有80%以上。  相似文献   

10.
对5种变质豆浆中的腐败微生物进行了分离,并对所分离的腐败微生物进行了感官实验,发现变质豆浆中的主要腐败微生物是三株细菌,而酵母、霉菌未检出。以二次灭菌的豆浆为培养基,通过正交实验确定了三株细菌中的最难杀灭细菌的有效灭菌方法:121℃下灭菌30min,同时添加300mg/kgNisin,该灭菌条件可使豆浆在37℃下贮存30天时细菌菌落未检出,但继续贮存至45天时,细菌菌落数超过100cfu/mL。  相似文献   

11.
针对豫北地区的大豆生产现状,从气候、土壤、品种、生态因素及市场需求等方面提出了优质大豆的发展策略与途径。  相似文献   

12.
In the western Sahel, indigenous plants become important staples when cereal harvests are inadequate to support populations inhabiting that region of Africa. The purpose of this study was to assess the nutrient content of several of these edible wild plants. The leaves of the following seven plant foods were analyzed: Ziziphus mauritiana, Cerathotheca sesamoides, Moringa oleifera, Leptadenia hastata, Hibiscus sabdarifa, Amaranthus viridi, and Adansonia digitata. The fatty acid, vitamin E, carotenoid, selected mineral and amino acid contents of these plant foods were determined. These same analyses were performed on the fruit of the Adansonia digitata. In quantitative and qualitative terms, Amaranthus viridis was found to be an excellent source of protein. Its amino acid composition compared favorably to that of a World Health Organization (WHO) protein standard. It also contained considerable amounts of the two fatty acids that are essential in humans (linoleic and -linolenic) and a number of minerals including iron, magnesium, calcium and zinc. The leaves of Hibiscus sabdarifa contained an appreciable quantity of protein the composition of which was comparable to the WHO standard. The mineral content of the leaves of this plant was also exceptionally high; noteworthy was its high zinc content. H. sabdarifa also contained significant quantities of the two essential fatty acids. Ziziphus mauritiana was an excellent source of the essential fatty acid linoleic acid and several of the metals including iron, calcium, magnesium and zinc. Its content of other essential nutrients, however, was rather low. In general, Adansonia digitata leaves were nutritionally superior to the fruit of the tree; however, the fruit did contain useful quantities of potassium, phosphorus, zinc and -linolenic acid. The Leptadenia hastata leaves were an especially good source of lutein and -carotene. These data should be useful to the people who inhabit the western Sahel in helping them devise healthy diets during times when cereal staples are in short supply.  相似文献   

13.
通过电解质外渗法和匍匐茎恢复试验对‘阳江’狗牙根及其12个通过形态鉴定选出的坪用价值高且花序密度低的诱变后代进行抗寒性鉴定。电解质外渗法结果表明:诱变后代间的抗寒性具有较大差异,其叶片半致死温度(LT50)的变异范围为-7.6~-0.2℃(最低值与最大值相差7.4℃);参试材料抗寒性由强到弱依次为M18>M4>M26>M28> M22>阳江>M29>M31>M10>M37>M16>M1>M25,其中,有5个诱变后代抗寒性优于亲本,分别是M18、M4、M26、M28、M22。匍匐茎恢复实验结果表明:诱变后代M1、M22、M26、M31、M25在0℃和-5℃低温胁迫后的恢复生长率都高于亲本,恢复能力均优于亲本;M10、M37、M28在-5℃低温胁迫下,恢复生长能力低于亲本,抗寒性相对较弱,M16和M4在0℃和-5℃低温胁迫下,恢复生长率都低于亲本,抗寒性明显弱于亲本。综合2种方法鉴定结果显示:诱变后代M1、M25的恢复能力较强;M4、M28的叶片抗寒性较好,青绿期较长;M22、M18、M26的叶片抗寒性和匍匐茎恢复能力均较强;M29,M31的叶片抗寒性和匍匐茎恢复能力与亲本相似;M10、M16、M37的叶片抗寒性和匍匐茎恢复能力均较弱,整体抗寒性较弱。  相似文献   

14.
Irrigation of Netted Gem potatoes was scheduled during three growing seasons by three methods: (a) when plants displayed first visual symptoms of moisture stress, (b) when indicated by a soil moisture budget involving estimated evapotranspiration, and (c) on the basis of tensiometer readings of soil moisture suction. When the tensiometer method of scheduling was used, the mean yields of tubers were 55.0 and 25.8 cwt/acre (6160 and 2890 kg/ha) higher than those obtained with the other two scheduling methods. Methods did not affect the specific gravity of potatoes. Method (a) scheduled irrigations least frequently. Scheduling by the budget method was not always adequate because it was based on the assumption that the crop extracted water from a constant 4 ft (1.2 m) profile from planting to full vegetative growth. In one year the budget method scheduled the first irrigation earlier than necessary and delayed the second irrigation during a critical period of crop growth. From full vegetative cover to harvest the irrigation schedules were alike for both the budget and tensiometer methods.  相似文献   

15.
以长沙县高桥相同嫩度茶鲜叶原料采用卷曲形毛尖茶加工工艺制绿茶为对照,分别对沅陵县齐眉翠峰、凤娇碣滩茶、干发茶和军大坪茶4种绿茶的主要生化成分与感官品质进行初步分析。结果表明,沅陵4种绿茶的茶多酚总量28.76%~30.34%,游离氨基酸总量2.35%~3.22%,咖啡碱含量3.00%~3.63%,水浸出物含量37.26%~40.07%,可溶性糖总量5.46%~5.65%,可溶性蛋白含量1.50%~1.74%,类黄酮化合物总量1.16%~1.79%,叶绿素总量1.36%~2.01%,儿茶素总量13.53%~16.20%。与对照相比,4种绿茶的茶多酚、可溶性糖和儿茶素总量均高于对照,除齐眉翠峰外其余3种茶样水浸出物和叶绿素总量均高于对照,除干发茶外其余3种茶样类黄酮化合物总量均高于对照。  相似文献   

16.
1 吉林省平安农业科学院大豆研究工作简介吉林省平安农业科学院大豆研究所 ,设在吉林省长春市西安大路种子大厦内。现有科技人员 6人 ,其中研究员 2人 ,农艺师 2人 ,技术员 2人 ,定向培养研究生 2人。大豆研究所的主要任务是选育稳产、高产、优质及抗病虫大豆新品种 ;同时密切  相似文献   

17.
18.
A broadcast application of PCNB (Terraclor) resulted in a reasonably uniform distribution of the chemical in the soil with the concentration decreasing in a linear fashion with increasing depth in the soil profile. A banded application resuluted in a considerably higher chemical concentration at the 4–6 inch depth than at the 0–2 or the 2–4 inch depths. The problem of the lack of uniformity of chemical distribution could probably be solved by altering nozzle placement and size and allow use of the band method of application to minimize grower cost. More complete disking in the case of the broadcast treatment would probably result in a relatively uniform distribution of the chemical but at higher cost to the grower. PCNB application rates of 10, 15 and 25 lbs per acre broadcast and 71/2, 10 and 121/2 lbs per acre in a band significantly reduced the severity ofRhizoctonia infection of Russet Burbank potatoes but did not increase potato yields significantly.  相似文献   

19.
Data from in vivo digestibility trial with four to six horses fed twenty-seven forage-based diets are used to calculate prediction equations for the digestibility of dry and organic matter, based on the crude ash (CA), crude protein (CP) and crude fibre (CF) contents of diets and faeces. The most precise prediction of dry-matter digestibility (r.s.d. = 0.032, R2= 0.80) was derived from a multiple regression including faecal (CP, CF) and dietary parameters (CF). Among faecal parameters, CP was the best single predictor of both digestibility (r.s.d) = 0.040, r2= 0.63) and dietary CP content (r.s.d = 0.028, r2= 0.59). For biological reasons we propose a non-linear model that allows prediction of dry- and organic-matter digestibility from faecal CP Content with reasonable Precision (r.s.d = 0.038, 0.036, r2= 0.65, 0.74, respectively). This will be adequate for many studies, especially for free-living animals in rangelands.  相似文献   

20.
橡胶树丛枝病病原的抗血清制备与应用   总被引:5,自引:1,他引:4  
以感染橡胶树丛枝病病原的长春花为材料,制备得到橡胶丛枝病病原菌抽提液,以抽提液为抗原免疫家兔,制备抗血清,经微量沉淀测定,抗血清效价为1:2048。应用橡胶丛枝病抗血清检测橡胶褐皮病,无症苗木检出率达30%-37%,可疑的褐皮病树检出率达85.7%。  相似文献   

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