长白山黑木耳蜜饯的研制

为探索长白山黑木耳蜜饯的加工工艺,以长白山黑木耳为原料,通过单因素试验和正交试验确定长白山黑木耳蜜饯的最佳生产工艺条件。结果表明:氯化钙添加量为1%、甘油添加量为0.7%、黄原胶添加量为0.3%、糖添加量为40%、柠檬酸添加量为0.6%、渗糖时间为40min、干燥时间为1.5h时,长白山黑木耳蜜饯感官品质最佳。     

BP神经网络指导番木瓜果肉制品开发

以热带水果番木瓜为原料生产果肉制品,采用模糊综合评价法对产品进行感官质量评价,通过单因素和正交实验确定柠檬酸、护色剂抗坏血酸、稳定剂羧甲基纤维素钠(CMC-Na)、山梨糖醇添加量,采用神经网络对果肉制品工艺参数进行优化,建立神经网络模型。结果显示,柠檬酸添加量为0.105%、抗坏血酸为0.112%,CMC-Na为0.098%,山梨糖醇为7.2%时,产品的感官得分为89.93。此条件下生产的产品色泽均匀,香气浓郁,口感佳,符合卫生安全标准。     

灵芝枸杞软糖的研制及其体外抗氧化性测定

本实验以破壁灵芝孢子粉、枸杞多糖为原料,通过单因素及正交试验研制灵芝枸杞软糖的配方,并对软糖的抗氧化性进行测定,结果表明:凝胶添加量为4.5%,复配比例为2:1(琼脂:卡拉胶);甜味剂果葡糖浆添加量为8%,白砂糖添加量为30%;原料(1:2)的添加量为25%;干燥条件为70℃。经过对不同浓度软糖液的抗氧化性测定,灵芝枸杞软糖具有一定的抗氧化作用。     

姜汁绿茶复合饮料的研制

本文以生姜和绿茶浸提液为原料,将生姜汁和绿茶浸提液按比例调配后,加入一定比例的蔗糖和柠檬酸调味制成生姜绿茶饮品。通过单因素试验和正交试验探究姜汁添加量、绿茶浸提时的茶水比、绿茶浸提液添加量、蔗糖添加量、柠檬酸添加量对姜汁绿茶品质的影响,确定了该饮料的最佳工艺条件。结果表明,当姜汁添加量为5.0%、茶水比为1:50、茶叶浸提液添加量为60%、糖添加量为7%、酸添加量为0.12%时,茶饮料的口感最佳。     

利用大豆浓缩蛋白乳清制备水苏糖的发酵条件

利用酵母对大豆浓缩蛋白乳清进行发酵处理制备水苏糖.在确定最佳起始发酵液的糖度为31.8Brix后,对温度、pH、接种量、装液量等工艺条件进行了单因素试验及正交试验,结果表明最佳发酵条件为:温度32°C,pH5.5,接种量8%,在此发酵条件下利用酵母对大豆浓缩蛋白乳清进行发酵处理48 h,水苏糖的纯度达到了90%,保留率为68%.     

酶法提高大豆分离蛋白酸溶性的研究

通过单因素试验研究了植酸酶添加量、酶解时间、pH、温度和料液浓度对大豆蛋白酸溶度、透光率和料液粘度的影响,在单因素试验的基础上对pH、温度、料液浓度和时间进行四因素三水平的正交试验,结果表明,当植酸酶添加量为0.6%时,酶解的最佳条件组合为pH3.0,温度40℃,料液浓度10%,酶解时间45 min,此时大豆分离蛋白的酸溶度为45.79%,透光率为68.5%,与优化前相比,分别提高了30.65%和29.4%。     

响应面法优化菠萝蜜淀粉-椰子油复合物的制备工艺

为确定快速粘度计（rapid visco analyzer, RVA）制备菠萝蜜淀粉-椰子油复合物的最佳工艺条件，探讨椰子油添加量、复合时间、复合温度3个因素对菠萝蜜淀粉-椰子油复合物的复合指数的影响。在此基础上，利用Box-Benhnken响应面法优化RVA制备菠萝蜜淀粉-椰子油复合物的工艺条件。此外，对比了菠萝蜜淀粉和复合物的糊化特性、膨胀力和溶解性。结果表明，菠萝蜜淀粉-椰子油复合物的最佳制备条件参数为：椰子油添加量为4%，复合时间为2.40 min，复合温度为90.70℃。在最佳条件下，菠萝蜜淀粉-椰子油复合物的复合指数理论值为24.64%，实际验证值为24.33%，拟合模型预测值与实际验证结果吻合。复合物的糊化温度、峰值黏度和谷值黏度高于原淀粉，而最终黏度和回生值有所下降，说明复合物的热稳定性提高；复合物的形成阻止了淀粉膨胀，导致膨胀力和溶解度相较原淀粉明显降低。     

千张豆腐生产中点卤工艺标准化研究

针对千张豆腐生产工艺中的点卤工艺影响产品品质及产量不稳定的问题,在传统千张豆腐生产工艺的基础上,对机制千张豆腐生产工艺中的点卤工艺进行标准化。通过单因素试验和正交试验对点卤工艺中的凝固剂种类、添加量、点浆温度、豆浆浓度等因素进行优化,结合感官评分、理化指标测定及质构特性分析得出的千张豆腐点卤工艺标准化参数为:凝固剂石膏与盐卤的配比(g∶g)为1.875∶1.100、点浆温度85℃、豆浆浓度9°。验证试验结果表明:标准化生产的千张豆腐与传统工艺制作的千张豆腐相比质量显著提高,含水量增加4.92%,总蛋白质含量增加2.87%,出品率增加7.87%,弹性增加1.63 mm,咀嚼性增加20.92 m J,硬度降低313.00 g,粘性降低0.03 m J,损耗率降低3.36%。     

菠萝蜜果醋发酵工艺的优化及香气成分分析

为了提升菠萝蜜的产品附加值,进一步丰富市场中果醋种类,本研究以菠萝蜜为原料,对菠萝蜜果醋发酵工艺进行优化并分析其香气成分。通过单因素试验探讨醋酸菌接种量、发酵温度、乙醇体积分数、初始pH 4个因素对菠萝蜜果醋产酸量的影响,然后采用4因素3水平的响应面设计优化得到最佳发酵工艺。结果表明,菠萝蜜果醋的最佳发酵工艺条件为醋酸菌接种量11%、发酵温度32 ℃、乙醇体积分数5%、初始pH 3.3,在此条件下菠萝蜜果醋的醋酸含量达(44.20±0.41)g/L。采用顶空固相微萃取法（head space-solid phase microextraction, HS-SPME）结合气相色谱-质谱联用技术（gas chromatography-mass spectrometry, GC-MS）,对菠萝蜜果醋的香气成分进行分析,检测出香气成分67种,主要成分是乙酸（26.15%）、乙酸异戊酯（12.78%）、异戊醇（11.01%）、乙酸乙酯（10.99%）、苯乙醇（4.72%）、正癸酸（3.61%）、苯甲醛（3.34%）、乙酸苯乙酯（3.12%）、辛酸（3.08%）、异戊酸（1.31%）、月桂酸乙酯（1.07%）。通过菠萝蜜果醋发酵工艺的优化和香气成分分析,制备出符合相关国家标准和行业标准的新型果醋,初步探明了果醋中香气成分的种类。     

响应曲面法优化鲜果豆丁制备工艺及其品质评价

以豆浆为基础原料,以感官评分和质构特性为主要评价指标,通过响应曲面法优化鲜果豆丁工艺配方。利用Design-Expert软件进行数据分析,得出鲜果豆丁的最佳配方为:木糖醇添加量为14%,柠檬酸添加量为0.3%,复合胶的添加量为明胶2.5%、琼脂0.5%,果肉的添加量为14%。在此最优条件下制备的大豆鲜果布丁感官得分为93,弹性为0.88,回复性为1.31,口感较好,具有独特的豆香风味。     

Mineral composition of some traditional Mexican teas

Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.     

Redox Status and Neuro Inflammation Indexes in Cerebellum and Motor Cortex of Wistar Rats Supplemented with Natural Sources of Omega-3 Fatty Acids and Astaxanthin: Fish Oil,Krill Oil,and Algal Biomass

Health authorities worldwide have consistently recommended the regular consumption of marine fishes and seafood to preserve memory, sustain cognitive functions, and prevent neurodegenerative processes in humans. Shrimp, crabs, lobster, and salmon are of particular interest in the human diet due to their substantial provision of omega-3 fatty acids (n-3/PUFAs) and the antioxidant carotenoid astaxanthin (ASTA). However, the optimal ratio between these nutraceuticals in natural sources is apparently the key factor for maximum protection against most neuro-motor disorders. Therefore, we aimed here to investigate the effects of a long-term supplementation with (n-3)/PUFAs-rich fish oil, ASTA-rich algal biomass, the combination of them, or krill oil (a natural combination of both nutrients) on baseline redox balance and neuro-inflammation indexes in cerebellum and motor cortex of Wistar rats. Significant changes in redox metabolism were only observed upon ASTA supplementation, which reinforce its antioxidant properties with a putative mitochondrial-centered action in rat brain. Krill oil imposed mild astrocyte activation in motor cortex of Wistar rats, although no redox or inflammatory index was concomitantly altered. In summary, there is no experimental evidence that krill oil, fish oil, oralgal biomass (minor variation), drastically change the baseline oxidative conditions or the neuro-inflammatory scenario in neuromotor-associated rat brain regions.     

Potential of dry fractionation of wheat bran for the development of food ingredients,part II: Electrostatic separation of particles

Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.     

<Emphasis Type="Italic">Pulque</Emphasis>, An Alcoholic Drink from Rural Mexico,Contains Phytase. Its <Emphasis Type="Italic">in vitro</Emphasis> Effects on Corn Tortilla

Pulque is made by fermenting the agave sap or aguamiel of Agave atrovirens with a whole array of microorganisms present in the environment including several lactic acid bacteria and yeasts such as Saccharomyces cerevisiae. Ascorbic acid was determined in pulque and aguamiel, respectively. Phytase activity in lees, liquid and freeze-dried pulque was assayed by measuring the appearance of phosphate from phytate by a colorimetric method likewise phosphate from phytate present in fresh corn tortilla was measured after in vitro incubation with pulque. Iron, zinc, calcium, magnesium and selenium contents were measured in pulque and corn tortilla as well as in nixtamalized corn flour (NCF), the latter is used to make instant tortilla, since corn provides most of the energy as well as most of the phytate in the Mexican rural diet. Pulque showed phytase activity but much less ascorbic acid and iron than previously reported; additionally, phytase in pulque hydrolyzed most of phytate’s corn tortilla. Lees, which is mostly made of pulque’s microbiota, significantly accumulated iron and zinc but no selenium. NCF was fortified with iron by the manufacturers but poorly blended. There were significant differences on selenium content between tortillas samples, apparently some soils in central Mexico are selenium deficient. Moderate pulque intake appears to increase the bioavailability of iron and zinc bound by phytate in corn.