咖啡豆奶的研究

探讨了咖啡豆奶加工工艺,采用感官评定确定了咖啡豆奶的最佳生产条件,结果表明,采用3%的接种量,豆奶发酵最佳条件为:保加利亚乳杆菌和嗜热链球菌之比为1∶1,乳糖3%,发酵温度为43℃,发酵时间为6h;咖啡豆奶的最佳配方为:酸豆奶55mL,咖啡量0.5g,水45mL;稳定剂的添加量为黄原胶0.05%,羧甲基纤维素钠(CMC-Na)0.1%,海藻酸钠0.01%。     

咖啡营养特性及营养诊断研究进展

饮料作物咖啡（Coffea）为茜草科咖啡属的多年生灌木或者小乔木,在我国主要种植于云南与海南两省。本文概述了咖啡的主要营养特性及咖啡营养诊断方面的研究概况,并指出咖啡营养诊断的研究方向。     

Additional evidence for oligogenic inheritance of durable host resistance to coffee berry disease (<Emphasis Type="Italic">Colletotrichum kahawae</Emphasis>) in arabica coffee (<Emphasis Type="Italic">Coffea arabica</Emphasis> L.)

Breeding for host resistance to coffee berry disease (CBD) in arabica coffee (Coffea arabica) was initiated some 35–40 years ago in Kenya, Ethiopia and Tanzania in response to severe CBD epidemics. The release of CBD resistant cultivars to the coffee growers has been in progress since 1985. The resistance of cultivars like Ruiru 11 (Kenya) and Ababuna (and other cvs in Ethiopia) appears to be of a durable nature, since confirmed cases of a breakdown of host resistance under field conditions have not been reported over the past 20 years. Host resistance to the hemibiotrophic fungus Colletotrichum kahawae is of a quantitative nature, but nevertheless can be practically complete in some genotypes of arabica coffee. There is still no consensus on the genetics of CBD resistance, some claiming convincing evidence for oligogenes (1–3 major genes) and others for polygenes determining CBD resistance. Results from genetic studies with germplasm from the centre of genetic diversity for C. arabica in Ethiopia are presented here. These together with the recent identification of molecular markers associated with and the mapping of one major gene, provides additional evidence for oligogenic inheritance of CBD resistance. The development of cultivars combining yield and quality with durable host resistance to CBD has contributed greatly to increased sustainability of arabica coffee production in Africa. It has also considerable relevance to arabica coffee in Latin America and Asia, where CBD is still a quarantine disease but with a risk of becoming endemic one day, just as has happened earlier with coffee leaf rust (Hemileia vastatrix).     

Mulching effects on soil nutrient levels and yield in coffee farming systems in Rwanda

Different combinations of organic mulch were applied in smallholder coffee farming systems to assess their effects on soil nutrient contents and coffee yield at three sites in different agro-ecological zones in Rwanda. Mulching systems consisted of Cymbopogon spp. (T1), Panicum spp. (T2), Cymbopogon spp. and Panicum spp. (T3), Eucalyptus spp. and Cymbopogon spp. (T4), mixed residues (T5) and un-mulched coffee used as control (T6). Mulch had significant and specific effects at each site (p < 0.001). T3 reduced soil pH value and exchangeable acidity at Kibirizi, while at Karongi and Ruli, these effects were observed with T4 and T5. T4 and T5 significantly increased the content of soil carbon (C), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg). The amount of nutrients released was regulated by the amount and type of mulch applied, the agro-ecological conditions and the soil properties at each site. The increased soil nutrient levels led to improved soil fertility conditions and increased coffee yields. The coffee yields were significantly increased with T1 at Karongi (p < 0.05) by up to 1.9 t ha⁻¹. T2 and T3 had significantly higher yields at Kibirizi. Yields at Kibirizi were 48% lower compared to yields at Karongi; at this site, T1, T2, T3, T4 and T5 increased yields by 57%, 26%, 31%, 20% and 28%, respectively, when compared to the no mulching treatment (T6). However, coffee yields over 1.9 t ha⁻¹ can only be obtained with additional applications of inorganic fertilizer at different rates depending on the agro-ecological zone and soil type.     

Resistance to Coffee Berry Disease in Arabica Coffee Variety 'Ruiru 11'

General and specific combining ability effects for resistance to coffee berry disease (Colletotrichum coffeanum Noack sensu Hindorf) in Coffea arabica variety ‘Ruiru 11’ and its parents were estimated according to the North Carolina Design II. A set of nine male parents and eleven females were crossed in all possible combinations to generate ninety-nine single cross hybrids constituting the ‘Ruiru 11’ variety. The parents and their hybrid progenies were screened and the mean score data analyzed for possible genetic variation. The contributions of the parents to the total genetic variance were low hence the low narrow sense heritability (h²= 0.04). The male and female parents accounted for 9.36 % and 0.96 %, respectively, while their interaction effect accounted for 89.68 %. In the analysis of combining ability for resistance, ExB3.96 and Cat.90 exhibited significant negative general combining ability (GCA). Specific combining abilities (SCA) were negative and significant for Cat.86 × ExB3.99, Cat.127 × ExB3.116 and Cat.119 × ExB3.879 crosses. The implications of these results in selection for highly resistant ‘Ruiru 11’ progenies are discussed.     

普洱市小粒咖啡病虫害种类调查分析

对云南省普洱市小粒咖啡主要栽种区病虫害及荫蔽树种类、杂草和荫蔽树与咖啡病虫害的关系进行调查研究。结果发现普洱市小粒咖啡害虫有13种,病害有7种,常用荫蔽树有17种。文中还分析杂草和荫蔽树与咖啡病虫害关系,就普洱市咖农的管理技术提出建议。     

Reciprocal recurrent selection applied to Coffea canephora Pierre

Summary Genetic parameters were estimated in trials planted in connection with a reciprocal recurrent selection programme applied to Coffea canephora in Côte d'Ivoire. Narrow sense heritability values, estimated from a breakdown of the analysis of variance, were high for architectural characters (0.22 to 0.78) and medium for tree vigour (0.13 to 0.40) and for bean weight (0.15 to 0.28). Calculated heritability values for the first two harvests were high (h²>0.7), but much lower for the following harvests (less than 0.2). Heritability estimates by parent-offspring regressions gave variable results, though they were often similar to those obtained by variance analysis, especially for bean weight. Phenotypic and genetic correlations between tree vigour traits and productivity were high. Bean weight was not correlated with vigour or production. Canopy diameter of 4 year-old trees was closely correlated with cumulated productivity from 2 to 5 years in the absence of development competition between trees, but the correlation was low if trees were in competition with each other. The consequences of the results for the choice of characters to be selected among intergroup hybrids or the parents of both populations are discussed.     

UPLC-MS/MS法测定生咖啡中的赭曲霉毒素A

建立了生咖啡中赭曲霉毒素A的超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。样品用甲醇提取后,直接在BEH C18色谱柱上以乙腈-0.1%甲酸水为流动相分离,采用多离子监测模式(MRM)进行测定。赭曲霉毒素A的线性范围为5.0～200.0 ng/mL,相关系数大于0.99,检出限为0.5μg/kg。4个水平的添加回收率在84.3%～109.2%,相对标准偏差小于7.35%。本方法灵敏度高、准确性好、成本低,适用于生咖啡中赭曲霉毒素A的检测。     

超微粉碎对咖啡果皮理化性质、结构及吸附能力的影响

本研究以咖啡果皮为原料,对其进行传统粉碎和超微粉碎,分别得到不同粒度的咖啡果皮粉。通过测定不同粒度粉体的持水性、膨胀性、持油性、溶解性和阳离子交换能力表明,随着粒度的减小,粉体的物理性状都有不同程度的改善,其中膨胀性和溶解性显著增加,分别从3.86 mL/g增加到6.14 mL/g、13.23%增加到44.50%;通过测定不同粒度粉体的吸附性能表明,随着粒度的减小,粉体对葡萄糖、胆固醇和亚硝酸盐的吸附能力增强,且超微粉与传统粉间差异显著,超微粉对三者的吸附能力分别为42.42 mg/g、29.34 mg/g、224.56 μg/g,吸附率分别为63.04%、67.38%、75.91%;扫描电镜和傅里叶变换红外光谱结果表明,超微粉碎能显著降低粉体粒度,但对粉体结构组成无显著改变。本研究结果表明超微粉碎能赋予咖啡果皮更好的加工和功能特性,下一步可考虑作为新的食品加工配料资源,提高咖啡副产物的利用价值。     

Impacts of weather,shade cover and elevation on coffee leafminer Leucoptera coffeella (Lepidoptera: Lyonetiidae) population dynamics and natural enemies

We assessed the influences of ambient temperature, rainfall, shade cover and elevation on seasonal abundance of coffee leafminer Leucoptera coffeella (Guérin-Ménèville) and its natural enemies in coffee farms in the Soconusco region of Chiapas, Mexico. Mined coffee leaves were most abundant during the rainy season (i.e. historical average rainfall >200 mm/mo, April–November) compared to the dry season (<100 mm/mo, December–March), and at low (<600 m asl) relative to high (>900 m asl) elevations. The abundance of mined leaves increased with rainfall, and decreased with maximum daily temperatures. Coffee leafminer survivorship was highest during the dry season (>40%), when predation was lowest (<10%). Predation was the main source of coffee leafminer mortality, and was greatest during the rainy season (>25%) when coffee leafminer incidence was highest (>30% mined leaves per plant). None of the weather variables that were evaluated (viz. maximum and minimum temperatures, and rainfall) significantly impacted parasitism ratios. Shade cover moderated on-farm temperatures, by reducing maximum daily temperatures and any potential, direct impacts of rainfall on coffee leafminer, by providing partial shelter from rainfall, but did not significantly affect coffee leafminer incidence. In 48 h laboratory trials, coffee leafminer oviposition was highest at 28 °C (∼15 eggs/female), minimal at 25 °C (∼3 eggs) and nil at 20 °C, and higher during night-time hours (>8 eggs/female/day) compared to day-time hours (<1 egg). Historical average temperatures were higher at low elevation (yearly average ca. 25 °C; range = 18.0–32.0 °C) than at high elevation (ca. 21 °C; 13.5–28.5 °C), and we predicted that physical environmental conditions (i.e. night-time hours with temperatures > 20 °C) were permissive of coffee leafminer oviposition during twice as many hours each year at low elevation (4060 h) compared to high elevation (2081 h). Overall, our results suggested that evident differences in the abundance of coffee leafminer between elevations may be due in considerable part to differences in ambient temperatures, particularly night-time temperatures, rather than rainfall, shade cover, or elevation per se.