Development of Tuanfeng Fermented Water Chestnut Beverage

With Tuanfeng water chestnut as a raw material, the optimal fermentation conditions for Tuanfeng fermented water chestnut beverage were obtained as follows ： pulp-to-water ratio at 1：2, inoculation amount of 2.00%, fermentation temperature at 41℃, and fermentation time of 8 h.

Effect of Water Chestnut Powder on Gel Properties of Silver Carp Surimi

[Objectives]The effects of water chestnut powder on the gel properties and quality of silver carp surimi were investigated.[Methods]The surimi gel was prepared by adding 0%,1%,2%,3%,4%and 5%of water chestnut powder to the surimi of silver carp.The gel properties,water-holding capacity,cooking loss,whiteness value,puncture and texture profile analysis(TPA)indexes of surimi products were determined to assess the effects of adding different amounts of water chestnut powder on surimi gel.[Results]The results showed that the gel strength,breaking force and depression distance of surimi products increased first and then decreased with the increase of the addition of water chestnut powder.Compared with the control group,the hardness and chewiness of surimi gel in TPA could be significantly improved by adding water chestnut powder.When the addition of water chestnut powder was 2%,the maximum water-holding capacity was 83.68%;the cooking loss rate was the lowest;and the whiteness value was the highest.Adding 2%of water chestnut powder could significantly improve the gel properties of silver carp surimi and obtain a good gel product.[Conclusions]This study provides a scientific basis for the effective utilization of water chestnut resources and the development of new fish surimi products.

Fermentation Conditions on the Production of Single Cell Protein Feed by Water Chestnut Peel

In order to improve the comprehensive utilization value of water chestnut peel and the income of farmers. Contents of crude protein （ CP）, total sugar and reducing sugar were taken as indicators. Effects of initial pH, ratio of yeast to fungi species, incubation time and liquid volume on production of single cell pro- tein （SCP） feed was studied, and technological conditions on production of SCP feed by water chestnut peel were optimized by orthogonal test. Results showed that the production of SCP feed by water chestnut peel was optimal when pH was 5.0, ratio of yeast to fungi species was 2： 1, fermentation time was 2 d and the liquid volume was 70 mL / 250 mL. Under the optimum conditions, content of fermentation CP was 64.25%, content of total sugar was 19.8%, content of reducing sugar was 5.0%, content of coarse fibre was 0.0% and content of ash was 8.04%.

Morphogenesis of Chinese Water Chestnut Pistil and Pollen Tube during Germination

With the forms of pistil stigma of " Guiti 2" Chinese water chestnut cultivar during the pollination as the object of observation,we reveal the pollination process of Chinese water chestnut from the microscopic point of view,to provide reference for Chinese water chestnut crossbreeding. The results show that the Chinese water chestnut pistil has 2- 4 stigmas which present white filament and vascular bundle forms,and the vessels on epidermis are thick with long translucent branched hairs; after pollination,pollen grains are tightly bound on branched hairs,and after identification,the pollen tube can penetrate branched hairs,continue to grow,and transfer the genetic material in pollen to vascular bundle.

Development of Water Chestnut Hard Biscuits

[Objectives] This study was conducted to develop a type of hard biscuit using water chestnut flour and thus to expand the application of water chestnut.[Methods]Hard biscuits were made from water chestnut flour and wheat flour.Then,their sensory quality indices were evaluated,and the optimal formulation of the biscuits was determined through single factor test and orthogonal array testing.[Results] The proportion of water chestnut flour was the most important factor that influences the sensory quality of hard biscuits,followed by the proportions of sugar,milk powder and baking powder.The optimal formula of the hard biscuit was adding 9.0 g water chestnut powder,8.0 g sugar,0.5 g baking powder,and 3.6 g milk powder to every 100.0 g wheat flour.The sensory quality score of the water chestnut hard biscuits made according to this formula was 86.0.And these biscuits were complete in shape,uniform in color,crisp and rich in nutrients.[Conclusions]The study enriches the types and improves the nutritional value of hard biscuits,which provides a new idea for the application of water chestnut.

Melatonin maintains the storage quality of fresh-cut Chinese water chestnuts by regulating phenolic and reactive oxygen species metabolism

Fresh-cut Chinese water chestnuts(CWCs)are prone to quality deterioration during storage,which does not meet consumer demand.In this study,the effect of exogenous melatonin(5 mmol·L^(-1))on the quality and potential mechanisms in fresh-cut CWC was investigated.The results showed that melatonin treatment alleviated the cut-surface discoloration of CWCs.Not only did this treatment significantly slow down the in-crease in browning degree and yellowness(b*)as well as the decrease in lightness(L*),but it also significantly delayed the loss of weight and total soluble solids.Further investigations indicated that melatonin-treated fresh-cut CWCs exhibited significantly lower total phenolics and soluble quinones and suppressed the activities of phenylalanine ammonia-lyase,polyphenol oxidase,and peroxidase.Meanwhile,when fresh-cut CWCs were treated with melatonin,the total flavonoid concentration was significantly decreased compared to the control.Ad ditionally,melatonin significantly inhibited the accumulation of H_(2)O_(2)and malondialdehyde as well as enhanced the activities of superoxide dismutase and catalase by promoting the production of O_(2)^(-·).In summary,melatonin treatment may delay the surface discoloration of fresh-cut CWCs by inhibiting phenolic compound metabolism and improving antioxidant capacity,thereby effectively maintaining the quality and prolonging the shelf life of fresh-cut CWCs.

Impact of fertilization on chestnut growth, N and P concentrations in runoff water on degraded slope land in South China

Growing fruit trees on the slopes of rolling hills in South China was causing serious environmental problems because of heavy application of chemical fertilizers and soil erosion. Suitable sources of fertilizers and proper rates of applications were of key importance to both crop yields and environmental protection. In this article, the impact of four fertilizers, i.e., inorganic compound fertilizer, organic compound fertilizer, pig manure compost, and peanut cake （peanut oil pressing residue）, on chestnut （Castanea mollissima Blume） growth on a slope in South China, and on the total N and total P concentrations in runoff waters have been investigated during two years of study, with an orthogonal experimental design. Results show that the organic compound fertilizer and peanut cake promote the heights of young chestnut trees compared to the control. In addition, peanut cake increases single-fruit weights and organic compound fertilizer raises single-seed weights. All the fertilizers increased the concentrations of total N and total P in runoff waters, except for organic compound fertilizer, in the first year experiment. The observed mean concentrations of total N varied from 1.6 mg/L to 3.2 mg/L and P from 0.12 mg/L to 0.22 mg/L, which were increased with the amount of fertilizer applications, with no pattern of direct proportion. On the basis of these experiment results, organic compound fertilizer at 2 kg/tree and peanut cake at 1 kg/tree are recommended to maximize chestnut growth and minimize water pollution.

荸荠收获机弹簧辊式泥果分离装置研制

针对荸荠收获泥果分离难、果实损伤率高的问题,根据旱地环境下荸荠采收作业需求,该研究提出一种由正反旋弹簧并排布置的荸荠收获机弹簧辊式泥果分离装置。通过对荸荠与弹簧辊的相对运动过程动力学分析,确定了影响荸荠收获泥果分离的关键因素为弹簧外径、螺距、相邻弹簧间距、高度差及弹簧转速、线径、作业速度。利用EDEM软件建立泥果混合物离散元模型,对弹簧辊结构参数与工作参数进行单因素试验,分析各因素对泥果分离效果的影响。以荸荠筛分率和土壤筛分率为指标进行二次回归正交试验,得到弹簧辊最佳参数组合为外径100 mm、螺距30 mm、间距9 mm、转速420 r/min,该参数组合下荸荠筛分率为80.00%,土壤筛分率为80.69%。进行仿真验证试验,对比试验结果与模型预测值,荸荠筛分率平均相对误差为2.09%,土壤筛分率平均相对误差为2.42%。以明果率、伤果率、破皮率、挖净率为指标开展模拟采挖试验,分析不同线径弹簧辊的泥果分离能力,确定12 mm线径弹簧兼具较好的振动筛分性能和较低的损伤率。通过实际收获试验测得作业速度0.21 m/s,作业效率0.19 m^(2)/s,碎土率75.61%,明果率82.42%,伤果率14.73%,破皮率7.01%。研究结果可为荸荠收获机研制和优化改进提供参考。

板栗全生长季树干液流及蒸腾耗水特征

【目的】明确板栗(Castanea mollissima Bl.)蒸腾耗水特征,为板栗园制定科学合理的水分管理措施提供理论参考。【方法】采用热扩散探针法,对‘大板红’板栗植株全生长季树干液流速率进行连续监测,并同步观测7个相关环境因子:太阳辐射(solar radiation,SR)、水汽压亏缺(vapor pressure deficit,VPD)、空气温度(air temperature,AT)、空气相对湿度(air relative humidity,ARH)、风速(wind speed,WS)、土壤温度(soil temperature,ST)和土壤湿度(soil relative humidity,SRH),解析板栗树干液流规律和耗水特征及其与环境因子间的关联性。【结果】板栗树干明显液流启动于5月3日,结束于10月26日,前后历时176 d。板栗全生长季晴天树干液流速率日变化呈单峰“几”字形曲线,其在6、7、8月每日启动到达峰值时间早于5、9、10月,而下降时间晚于5、9、10月,致6、7、8月份液流速率峰值持续时间长于5、9、10月。板栗全生长季液流速率日均值、日均耗水量和月耗水量由高到低排序均为8月>7月>6月>9月>5月>10月,其中显著性检验表明7月和8月之间无显著差异,但显著高于其他月份。夜间液流量占比由高到低排序为10月>9月>5月>6月>7月>8月,其中显著性检验表明10月、9月和5月显著高于6月、7月和8月。板栗全生长季树干液流速率与太阳辐射、水汽压亏缺、空气温度和风速均呈极显著正相关,而与空气相对湿度均呈极显著负相关。分别建立了5—10月板栗树干液流速率与7个环境因子的6个回归模型。【结论】板栗树干有明显液流始于5月初、终于10月末;7—8月是板栗的关键需水期;建立的板栗植株液流速率与环境因子的回归模型,可用于通过环境因子估测不同月份及整个生长季的植株耗水量。

振动挤压式荸荠收获机的设计与试验

针对旱收荸荠(Eleocharis dulcis)时人工劳动强度大、作业效率低和果土分离困难的问题,设计了一种振动挤压式荸荠收获机。通过对作业过程中荸荠土块的受力分析,确定了影响分离性能的关键参数为振动板振幅、振动板振频和钉齿辊转速,并根据已有经验初步确定关键参数取值范围。以振动板振幅、振动板振频和钉齿辊转速为影响因素,以土层破碎率为评价指标,利用Design-Expert 10.0设计CCD中心组合试验,通过RecurDyn-EDEM耦合进行仿真,确定当振动板振幅为33.04 mm、振动板振频6.63 Hz、钉齿辊转速336.72 r/min时,存在较优破碎效果,土层破碎率为93.58%。以振动板实际振幅32.41 mm、振频6.5 Hz,钉齿滚转速330 r/min进行田间验证试验,结果显示,实际土层破碎率93.54%、明荠率80.33%、损伤率28.08%,碎土效果好,与仿真结果拟合度高。试验结果表明,通过增强土层破碎效果进而提高果土分离程度,使得分离后的荸荠抛撒在表层,便于人工捡拾。

马蹄脆片微波真空干燥工艺优化及其水分变化

以马蹄为原料,采用微波真空干燥技术干燥马蹄脆片,考察微波功率、干燥温度、真空度、切片厚度对马蹄脆片色差值、总糖含量、脆度的影响,以响应面试验优化干燥工艺,采用低场核磁共振技术研究马蹄脆片干燥过程水分变化情况。结果表明,微波真空干燥马蹄脆片的最佳工艺为微波功率2.0 kW、干燥温度71℃、真空度-95 kPa、切片厚度3.1 mm,所得产品色差值、总糖含量、脆度分别为3.42、50.51 mg/100 g、464.96 g,产品色泽白亮,酥脆可口,马蹄风味浓厚。低场核磁共振检测结果表明:马蹄片内部主要存在3种状态水,分别是自由水、不易流动水及结合水,其中自由水占比较高、结合水和不易流动水的比例相对较低,在最佳工艺下到达干燥终点时自由水完全除去,只剩少量的不易流动水以及结合水。

速溶型马蹄脆脆粉配方优化及性能分析

为开发一款新式马蹄速溶型产品,以结团率、凝沉率、感官评分、质构特性、糊化特性以及流变特性作为评价标准,进行单因素试验和响应面优化试验,研制出马蹄脆脆粉的最佳配方为马蹄淀粉33.27%、30~40目马蹄全粉37.33%、白砂糖12.53%、麦芽糊精10.15%、β-环状糊精6.71%。验证试验结果表明,产品的结团率1.37%、凝沉率1.30%、感官评分96.49、糊化温度50.8℃,随着剪切力的上升整体呈剪切变稀、黏度下降的趋势。此配方制备的马蹄脆脆粉口感细腻、不易结团下沉、溶液悬浮稳定性能良好、马蹄风味浓厚,脆口感强烈、营养丰富,且糊化性能和流变性能优良,是一款十分具有市场前景的速溶产品。

荸荠皮棕色素在食品加工与贮藏中的稳定性及抗氧化性研究

探讨荸荠皮棕色素在马蹄糕、油炸薯条加工与米醋贮藏中的稳定性及相同条件模拟处理下的抗氧化活性变化。将自制的荸荠皮棕色素提取物应用于马蹄糕(蒸煮)、薯条(油炸)、米醋(低pH贮藏)等典型食品加工或贮藏中,以色价及其变化率、总色差及其变化率为指标探讨其稳定性,并通过模拟加工条件处理后,研究荸荠皮棕色素的抗氧化活性变化。研究表明,荸荠皮棕色素适用于马蹄糕蒸煮加工,蒸煮时间20 min为宜;荸荠皮棕色素可用于油炸薯条加工,以190℃下油炸60 s最佳;荸荠皮棕色素不适用于35℃下紫外光照及低pH (2.45)的米醋贮藏。经模拟条件处理后的荸荠皮棕色素ASTS、DPPH清除能力均下降,抗氧化活性降低。

米糠提取物处理对鲜切荸荠黄化的影响

【目的】经削皮和切分的鲜切荸荠在贮藏过程中极易黄化,严重影响产品的外观品质。旨在寻找一种有效的鲜切荸荠黄化抑制手段,延缓贮藏过程中的品质劣变。【方法】采用米糠提取物浸泡处理鲜切荸荠,通过测定鲜切荸荠在贮藏过程中的色度、总黄酮含量、酶活性和黄酮代谢相关结构基因和转录因子的表达变化,研究米糠提取物对黄化的抑制效果及其机理。【结果】米糠提取物处理可有效抑制鲜切荸荠贮藏过程中L*值的下降、贮藏6 d时L*值仍>70,显著延缓鲜切荸荠b*值的上升、贮藏6 d时b*值为20.62且显著低于对照组。米糠提取物处理显著抑制鲜切荸荠组织中总黄酮含量的上升,而对照组鲜切荸荠贮藏至6 d时黄酮含量上升至0.377 mg/g、是0 d的2.96倍。对照组鲜切荸荠PPO活性呈先下降后上升趋势,米糠提取物处理组PPO活性在贮藏2~6 d均显著低于对照组;对照组PAL活性在贮藏过程中快速上升,贮藏6 d时达71.03 U/g、是0 d的3倍,而米糠提取物处理则可显著延缓PAL活性上升。荧光定量PCR分析结果表明,米糠提取物处理可显著下调鲜切荸荠黄酮合成相关4个结构基因(CwPAL、CwC4H、CwCHI和CwCHS)的表达;参与黄酮代谢调控的CwMYB12和CwMYC2转录因子的表达也受米糠提取物处理的显著抑制。【结论】米糠提取物可有效延缓鲜切荸荠贮藏过程中的黄化现象,对黄酮类物质的积累和黄酮代谢均有显著的抑制作用;为进一步阐明荸荠黄化的分子机理提供基础,并为鲜切荸荠的保鲜和护色处理提供参考。

马蹄三部位生物活性初筛

为探究马蹄地上茎、皮、球茎三部位的生物活性,采用超声辅助提取法得到马蹄三部位的水提物和醇提物,分别评价其抗氧化、抑菌和体外降糖活性;同时利用果蝇II型糖尿病模型,考察马蹄三部位原料的体内降糖降脂功效。结果表明,马蹄三部位提取物都具有DPPH、ABTS+自由基清除能力和α-葡萄糖苷酶、α-淀粉酶抑制能力,且都与浓度呈一定剂量关系,马蹄皮水提物的抗氧化效果最强,马蹄地上茎水提物体外降糖作用最强;除黑曲霉外,马蹄三部位提取物对其他三种种菌都有一定的抑制作用,尤其对金黄色葡萄球菌抑菌作用最强;马蹄三部位均能降低果蝇体内的海藻糖、甘油三酯含量,且对总蛋白含量无显著影响,以马蹄皮降糖功效最强、马蹄球茎降脂作用最强。

荸荠香菇复合酱的研制

荸荠中含有丰富的营养,口感清脆,将其加入到香菇酱中,可很好地改善香菇酱的品质。采用单因素试验和正交试验的方法,在预处理荸荠的过程中,优化荸荠的热烫温度和热烫时间,通过感官评定标准进行评分,得出其最佳的口感;在香菇复合酱的炒制过程中,对豆瓣酱用量、香菇用量、荸荠用量不断进行优化,并按照感官评定标准对其进行评分,得出荸荠香菇复合酱的最佳配方。结果表明,荸荠的热烫温度90℃,热烫时间20 min时制得的荸荠口感清脆,香气浓郁;豆瓣酱用量12.5 g,香菇用量30 g,荸荠用量25 g时,制成的复合酱味道适口、滋味协调、香气扑鼻。

响应面优化羧甲基醚化法制备马蹄抗性淀粉的工艺及理化性质研究

本实验以马蹄淀粉为原料通过羧甲基醚化法制取抗性淀粉,以羧甲基醚化马蹄抗性淀粉的得率为评价指标,通过单因素试验和Box-Behnken响应面试验优化其制备工艺,并对所得产品进行感官评价和理化指标分析。结果表明,羧甲基醚化法制备马蹄抗性淀粉的最优工艺参数为马蹄淀粉乳浓度12%,醚化剂用量120%,醚化温度43℃,该工艺下马蹄抗性淀粉得率为75.85%,与预测值76.02%接近,表明实验结果可靠。通过此方法可以便捷高效地生产出持水性强、颗粒较为完好、品质优良的马蹄抗性淀粉,为工业化生产提供了理论参考。

板栗营养诊断及水肥一体化技术研究

合理施肥是板栗提质增产的重要手段,施肥不当会对农业生产及土壤环境造成不良影响。在农业现代化进程中,精准施肥对于我国板栗产业可持续发展具有重要意义。本文综述了营养诊断结合水肥一体化技术的板栗精准施肥技术,分析板栗精准施肥的现状和存在的问题,为板栗的施肥研究提供基础,推进现代农业的可持续发展。

4BZ-800型荸荠收获机设计与试验

针对荸荠(Eleocharis dulcis)收获劳动强度大和可应用于实际生产的收获机具匮乏的问题,结合荸荠种植田土壤条件和现有人工收获方式,设计了一种应用于带水收获的自走式荸荠收获机。该机由行走系统、传动系统、旋转扰动装置、提升分离装置、收集装置等组成,整机传动系统分为液压传动部分和机械传动部分,液压传动部分为收获机行走系统和挖掘收获装置提供动力,可实现机具行走速度控制、挖掘收获装置高度调节、旋转扰动装置转速控制、提升分离装置转速控制,机械传动部分可为各级旋转扰动辊及提升分离装置间提供稳定的转速差,保障收获过程顺利进行。三级旋转扰动辊构成旋转扰动装置,实现对土壤和水分的充分扰动混合;齿形挖掘铲和升运链构成提升分离装置,完成荸荠果实的挖掘、果土分离、升运工作。田间试验结果显示,该机可一次性完成荸荠的挖掘、果土分离、升运、收集等工作,试验条件下该型荸荠收获机田间道路最大行驶速度为0.97m/s,田间差速转向最小转向半径为2.1 m,原地转向半径为1.3 m,最大爬坡角度为24.2°,果实挖净率为53.19%,损伤率4.21%。

超声辅助复合酶法提取马蹄渣不溶性膳食纤维工艺优化及品质对比

以淀粉型马蹄加工副产物果渣为原料,采用超声辅助复合酶法提取制备马蹄不溶性膳食纤维(Water Chestnut Insoluble Dietary Fiber,WIDF),通过单因素试验考察复合酶添加量、料液比、超声功率对WIDF提取率的影响,设计响应面试验对提取工艺进行优化,分析影响各指标的主次因素及因素间的交互作用并建立二次回归模型,优化得到最佳工艺参数加以验证,并对比传统复合酶法提取WIDF的品质功能特性。结果表明:建立WIDF提取率的回归方程模型极显著(P<0.01),可用于对超声辅助复合酶法提取WIDF的提取率指标进行分析和预测,优化得到最佳工艺参数:酶质量分数9%,料液比1:15,超声功率320 W,在此条件下进行验证试验,得到WIDF提取率高达67.60%,对比传统复合酶法,提取率提高107.36%、WIDF的持水力提升34.33%、胆固醇吸收性能提升35.77%,该研究可为马蹄渣的高值化综合利用提供一定理论参考依据。