山东烟叶感官质量与物理化学指标相关性研究

为了分析山东烟叶感官质量与物理化学指标的相关性,解析烟叶品质的化学基础和物理标识,采集典型中部和上部烟叶样品,通过感官质量评价、理化检测和数理统计分析,并对叶位、地域分布差异进行了比较。结果表明,山东上中部烟叶物理指标总体适宜,化学成分总体相对协调,感官质量总体较好,地域分布差异显著。中部叶在适宜范围内指标的比例高于上部叶。感官质量评价指标与化学成分和物理指标进行典型相关分析,分别得到3对和两对显著性典型变量,对典型变量影响较大的感官质量评价指标为杂气、余味、香气质,影响较大的化学成分指标为还原糖、总糖、两糖比、氯、总氮和烟碱,物理指标为叶宽、单叶重、叶片厚度,叶面密度和叶长。其中,杂气指标与钾氯比呈显著正相关,与氯、半纤维素呈显著负相关;余味与钙、氮碱比、钾氯比、叶宽、含梗率呈显著正相关,与淀粉、烟碱、钠、硫、氯、两糖比、叶片厚度、叶面密度呈显著负相关;香气质与钙、钾氯比、叶宽、含梗率呈显著正相关,与总氮、烟碱、钠、氯、两糖比、叶片厚度、叶面密度呈显著负相关。今后可采取相关措施进行调控,为产区烟叶质量提升提供理论参考。     

涞水县设施蔬菜化肥与农药施用现状及对策

为进一步提高设施蔬菜生产技术水平,对涞水县设施蔬菜生产温室进行调查,通过调查设施设备、主栽作物、种植模式、销售渠道、经济效益等基本情况,发现存在基础配套设备落后、种植户管理水平差异较大等问题;通过调查涞水县温室蔬菜栽培中化肥、农药使用情况,发现存在过度依赖化学农药、施用方式粗放、缺乏合理施用方案、化肥农药安全使用意识差...     

沙棘木蠹蛾幼虫化学防治的研究

针对沙棘木蠹蛾的生物学特性，采用干基喷雾、浇根、排粪孔注药、熏蒸等化学防治方法防治其幼虫，进行了大量野外试验。试验结果表明，在这些防治方法中，只有磷化铝熏蒸可称得上是一种经济、有效、可行的防治方法。夏季日均温在21-25℃时，以每株树1丸(3．2g)的剂量进行根部熏蒸，防治效果可达82．61％，防治成本为191．4元／hm^2。     

油茶炭疽病的化学防治研究

本研究使用14种杀菌剂对油茶炭疽病进行了室内和田间的防治试验。结果表明，扑菌清、叶斑净和宝宁的效果较好，同时对杀菌剂在田间的施用方法也提出了建议。     

几种化学药剂和微生物菌剂对腐烂茎线虫的室内触杀活性

本研究比较了5种化学药剂和4种微生物菌剂对腐烂茎线虫的室内触杀活性,并在此基础上进一步探究了化学药剂与微生物菌剂复合使用的效果.结果 表明,在5种供试化学药剂推荐浓度条件下,70％噁霉灵可湿性粉剂26.92 g/L对腐烂茎线虫的触杀效果最好,72 h的校正死亡率可达87.32％,20％噻唑膦水乳剂6.06 g/L与41...     

BIOLOG在土壤微生物群落功能多样性研究中的应用

目的研究海南热带地区典型植被类型土壤微生物群落结构特征,揭示植被特征和土壤理化特征对土壤微生物群落的影响。方法利用 BIOLOG-ECO 技术,对海南热带地区6种典型植被类型的土壤微生物功能多样性进行研究。结果不同植被类型土壤微生物的平均每孔颜色变化率(average well color development,AWCD)曲线基本一致,但碳源利用能力强弱有别。不同植被类型土壤192 h处的AWCD值大小顺序为：混交林>半红树林>次生林>椰子林>湿加松林>木麻黄林。不同林分类型对六大类主要的碳源利用率存在差异,混交林、半红树林、次生林和椰子林4种植被类型对碳水化合物、氨基酸类和多聚物的利用率最高,而木麻黄林和湿加松人工纯林土壤微生物对六大类碳源的利用率均不高,其中氨基酸类和羧酸类碳源是这2种人工纯林主要碳源利用形式。不同植被土壤微生物McIntosh指数、Shannon-Wiener指数、Simpson指数和Pielou指数也表现为混交林、半红树林和次生林高于人工纯林。主成分分析表明：不同植被类型土壤微生物群落代谢多样性能够明显区分,其中PC1可以解释所有变量方差的47.32%, PC2可以解释所有变量方差的31.58%,累计贡献达到78.90%。相关性分析表明：土壤微生物群落多样性各指标与土壤有机碳和全氮之间呈极显著正相关 (P<0.01),与土壤pH呈负相关,与土壤含水量呈显著正相关 (P<0.05)。结论相比纯林,人工混交林对于改善土壤微生物群落特征具有重要作用。     

回生抗性淀粉种类对米淀粉凝胶形成的影响

为寻找改善普通米淀粉制品的结构及品质的新型食品添加剂,该文以普通米淀粉为原料,采用快速黏度分析仪、扫描电子显微镜、质构分析仪、全自动X射线衍射仪及示差扫描量热仪等手段,研究添加锥栗、马铃薯与绿豆回生抗性淀粉(retrograded resistant starch,RSⅢ)对米淀粉凝胶微观结构及理化性质的影响。结果表明:添加锥栗、马铃薯及绿豆RSⅢ对米淀粉凝胶的结构及性质产生显著影响(P0.01),以锥栗RSⅢ的作用最为突出。添加锥栗、马铃薯与绿豆RSⅢ对米淀粉糊的黏度特性没有影响(P0.05)。未添加RSⅢ的米淀粉凝胶存在很多不规则、深浅不一的大洞,而加入RSⅢ使米淀粉凝胶的网状结构变得更为规整、致密,且其胶着性与黏聚性变化不大(P0.05);添加锥栗、马铃薯与绿豆RSⅢ后能加速米淀粉凝胶的形成,与未添加RSⅢ的米淀粉凝胶比,其硬度分别增加了2.38、1.97和1.25倍(P0.01),黏着性分别增加2.56、1.99和1.32倍(P0.01),弹性增加1.07、0.81和0.53倍(P0.01)。米淀粉以A-型晶体占优,锥栗RSⅢ以V-型晶体占优,马铃薯与绿豆RSⅢ均以B-型晶体占优;不加或加入RSⅢ的米淀粉凝胶粉末都转变为以V-型晶体为主,且总相对结晶度没有改变(P0.05)。加入RSⅢ后的米淀粉糊除有低温吸热峰外还出现高温吸热峰,是否添加RSⅢ对低温吸热峰的温度参数影响不大(P0.05),但吸热焓显著降低(P0.01);而对于高温吸热峰,添加马铃薯与绿豆RSⅢ的各项参数没有差别(P0.05),但比添加锥栗RSⅢ的显著增高(P0.01)。可见添加不同来源的RSⅢ可以有效改善米淀粉凝胶的结构与品质。该研究结果为抗性淀粉用于提高米制品品质与营养功能的研究和生产提供了重要参考。     

Effects of Injection of Protein Solutions Prepared from Fish By-products on Yield and Chemical Properties of Chilled and Frozen Saithe (Pollachius virens) Fillets

Fish gelatine and protein solutions prepared from saithe by-products were injected into saithe fillets. Effects on weight changes, water holding capacity, and chemical composition of the fillets were investigated after chilled (2, 5, and 7 days) and frozen (14 and 49 days) storage. The results showed that higher weight yields were obtained by adding proteins and salt to the fillets in comparison with only salt, especially in chilled fillets. The drawback of the injection was that higher drip losses were found during storage and thawing than for untreated fillets. Effects of injection on water content were only significant after 2 days of chilled storage, but differences leveled out after longer storage time and with freezing and thawing of the fillets. The procedure applied in this study seems to be promising for utilization of by-products such as trimmings as an ingredient in higher value products like fillets, in comparison to mince products.     

Quality Indices of Squid (Photololigo duvaucelii) and Cuttlefish (Sepia aculeata) Stored in Ice

The objective quality indices of squid (Photololigo duvaucelii) and cuttlefish (Sepia aculeata) stored in ice were compared with the subjective counterparts. Sensory (overall quality rating, quality index method [QIM], and multisample difference test), microbiological (total viable count [TVC], psychrophilic count), chemical (trichloroacetic acid-soluble peptide [TCA-soluble peptide], trimethylamine nitrogen [TMA-N], total volatile bases nitrogen [TVB-N], ammonia content, and protein pattern), and physical analyses (expressible drip, color, and texture) were determined in both species during 16 days of iced storage. As storage time increased, TCA-soluble peptide, TVB, ammonia content, and expressible drip were increased (p < 0.05). TMA content was markedly increased after 10 and 8 days of storage in squid and cuttlefish, respectively. Both TVC and psychrophilic count increased as the storage time increased (p < 0.01). Myosin heavy chain was degraded with coincidental decrease in shear force and sensory texture during storage (p < 0.05). According to the overall rating score, shelf life of both species in ice was estimated to be 6 days. The increases in ammonia content and expressible drip were highly correlated with the decrease in overall quality rating and increase in quality index score of squid and cuttlefish (p < 0.01).