CO2浓度和温度对柿子脱涩效果的影响

以新鲜涩柿果为试材,采用CO2脱涩法对柿子进行脱涩,研究了温度和CO2浓度对柿果的涩度、硬度和可溶性固形物含量的影响.结果表明:鲜涩柿在25℃、CO2浓度60%条件下进行脱涩,24h就可以脱去涩味,并保持较高硬度和原有品质.     

土壤干旱与柿叶片膜脂及脂质过氧化的关系

在不同灌水条件下,对盆栽柿幼树叶片组织相对含水量,细胞透性,超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性,膜脂脂肪酸组分和脂质过氧化作用产物——丙二醛(MDA)含量进行测定,结果表明:当水势Ψ_S下降时,细胞透性(PERM)增大,SOD和CAT活性下降,脂质过氧化作用增强,膜脂中不饱和脂肪酸含量下降,饱和脂肪酸含量升高。试验证明:土壤水势(?)_S=-3.80±0.47bar,各指标变化最明显。本试验条件下,幼柿叶片SOD活性,CAT活性,MDA含量,PERM,不饱和脂肪酸指数(IUFA)与组织相对含水量(RWC)和土壤水势(Ψ_s)间具显著相关关系。     

Chemical structures of the condensed tannins in the fruits of Diospyros species

The structural variety of the condensed tannins (proanthocyanidins) in the fruits of 16Diospyros species are reported. Eleven species contained condensed tannins mostly consisting of a mixture of catechin (CA) and gallocatechin (GCA) repeating units; the other five species did not. The GCA content in the CA-GCA total varied from 0.3% to 84.6%. The number of esterified gallic acid per one flavan repeating unit (degree of galloylation, DG) ranged from 0.01 to 0.89. The GCA content was found to be proportional to the DG values. Thus, 16Diospyros species tested may be classified into five groups by the analytical data of their condensed tannins. It may be interesting to compare their structural characteristics with those of the condensed tannins in other fruits, leaves, woods, and barks from the viewpoint of their biosynthesis and function in the plants.Part of this paper was presented at the 46th Annual Meeting of the Japan Wood Research Society, Tokyo, April 1995     

柿叶提取黄酮类化合物方法及鉴定

以柿叶为原料,研究了提取黄酮类化合物的不同方法,并对提取物进行分离研究.通过比较不同方法的提取结果,说明用乙醇作为提取荆所提取出的芦丁含量最高;用微乳液展开剂对提取物进行薄层色谱法分离鉴定,得出柿叶中含有黄酮化合物中的黄酮醇类,为进一步研究柿叶中黄酮类化合物提供借鉴.     

柿子果醋饮料的研究

探讨了柿子果醋饮料的加工工艺,在此基础上,对影响柿子果糕品质的柿子浓缩汁、白砂糖等因素进行了研究,旨在为柿子果醋饮料的加工提供理论和技术参数。     

Effect of antioxidants in controlling enzymatic browning of minimally processed persimmon ‘Rojo Brillante’

‘Rojo Brillante’ is an important variety of persimmon that after removal of the astringency with high levels of CO₂, maintains firmness and sweetness, making possible its commercialization as a fresh-cut commodity. However, the commercial success of the product is limited mainly by enzymatic browning. This work presents the effect of a wide range of antioxidants on enzymatic browning of ‘Rojo Brillante’ persimmon combining in vitro (extracts and precipitates) and in vivo (cut tissue) studies. Preliminary screening of the antioxidants, determined by absorbance and color measurements of persimmon extracts and pellets, showed that 4-hexylresorcinol (Hexyl), citric acid (CA) and calcium chloride (CaCl₂) were effective at controlling browning at 10 mM; whereas, ascorbic acid (AA) required a higher concentration (25 mM). Peracetic acid, cyclodextrin, cysteine, and hexametaphosphate were not effective at controlling browning, even at a concentration of 50 mM. In in vivo studies, AA (1.12%) and CA (0.21%) were the most effective treatments to control enzymatic browning of fresh-cut material, reaching the limit of marketability in 5–7 days, whereas, Hexyl and CaCl₂ did not reach 1 day of storage. The results showed that optimum concentrations in cut tissue did not always correlate with the in vitro studies, indicating that antioxidants have an effect not only in browning reactions, but also in metabolic activity and cell wall changes during wound-induced reactions. The results provide relevant information for further development of minimally processed ‘Rojo Brillante’ persimmon during storage at 5 °C.     

渭北旱原柿树苗嫁接试验

苗木培育是渭北旱原柿树生产面临的困难之一。嫁接是培育高质量柿树苗的主要措施。本文对柿树砧木苗培育,砧木苗龄、粗度选择以及嫁接时间、嫁接方法,嫁接技术等进行了试验,探索出一条本地区比较实用的柿树嫁接苗培育技术,期望在生产上有一定参考价值。     

高浓度CO2和1-MCP处理对磨盘柿脱涩和保脆效果的影响

以磨盘柿为试验材料,采用高浓度CO2和1-MCP双重处理,观察室温条件下的脱涩和保脆效果.结果表明,在20 ℃条件下90～95%CO2处理48 h能使磨盘柿完全脱涩,而80～85%CO2处理48 h,不能完全脱涩,同时1-MCP处理有助于抑制果实的呼吸作用,有效延缓了脱涩后果实的成熟和软化,可以明显抑制柿果实硬度、可溶性固形物含量、可溶性单宁含量的变化.0.50 μl/L浓度1-MCP处理的对硬度的保持作用好于1.00 μl/L浓度1-MCP.     

日本斤柿栽培技术

从果园选址、园地对环境的要求、品种选择、科学管理、病虫害综合防治等方面,介绍了安阳地区生产日本斤柿的技术规程。     

陕西柿树主要病虫害及其综合防治技术体系研究

2002～2003年调查研究了陕西柿树病虫害的种类及为害情况，确定以柿蒂虫、柿绵蚧、柿粉蚧、柿炭疽病、柿角斑病和柿圆斑病等为主控对象。提出以农业防治为基础，药剂防治为重点，结合植物检疫和生物防治组成综合防治体系。经过实施，取得明显的经济、社会和生态效益，对陕西柿子产业发展具有重要意义。