摘要:

In the last twenty years products bearing the term ‘natural’ have proliferated in the marketplace. Major food companies have made ‘natural’ claims often with a disclaimer that ‘no artificial preservatives or other such additives have been added’. In the 1970s, the Federal Trade Commission staff developed a two pronged standard encompassing the use of additives and ‘minimal processing’; it was not adopted and there is still no federal standard for the term. However, terms such as ‘natural’ and ‘minimal processing’ continue to be used to describe foods that, contrary to consumers’ expectations and the earlier proposal, are produced with complex processing technologies. As part of the federal legislative mandate to develop standards for production of organic foods, processing standards are also being proposed. It appears that groups developing these standards are not considering the inclusion of a ‘minimal processing’ prong, although there may be a need for this later. In this paper we have studied the attitudes and perceptions of professionals in the natural foods industry regarding the categorization of unit operations based on their level of acceptability for the production of foods containing organic ingredients. We conclude that such a categorization could be used as a basis for developing industry-specific processing guidelines.

ISSN:0144-8765    

DOI:10.1080/01448765.1995.9754742

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Field trials were carried out in northeastern Uttar Pradesh (India) to determine the effectiveness of the aphid parasitoidTrioxys indicusSubba Rao & Sharma against the cucurbit aphidAphid gossypiiGlover onLagenaria vulgaris(bottle gourd),Luffa cylindrica(ghia torai) andCucurbita maxima(pumpkin). Two initial inoculative releases of the parasitoid with the rate of 10 mummies/m2during the first and third weeks of December decreased the population growth of the aphid onL. vulgarisandL. cylindrica.A 20 to 50% reduction of the aphid number was noticed within 15 days after the first release in the fields on the two crops. The second release of the parasitoid further reduced the population by up to 65–70%. The rate of parasitism in natural conditions (control fields) and in experimental fields (where the parasitoids were released) was found to be density-dependent except in the fields ofC. maxima.The results demonstrated the potential ofT. indicusagainstA.gossypiiin a cucurbit habitat.

ISSN:0144-8765    

DOI:10.1080/01448765.1995.9754743

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The effect of long-term continuous fertilized and unfertilized corn and bluegrass crops on the structural stability status of a clay loam soil was studied. Water-stable aggregates were measured with and without an ethanol pretreatment and before and after the extraction of unbound lipids and after hydrophobic lipids were extracted with chloroform. Compared to corn, sod and wooded plots had three to four times more stable aggregates associated with the dispersive and dissolution action of water and two to three times more stable aggregates associated with slaking forces. The data also indicate that the stability of aggregates associated with bound organic materials was affected by cropping history rather than fertilization. Although the unbound lipids varied significantly between treatments, the unbound lipids were responsible for a similar amount of stable aggregates when compared against dispersive and dissolution action of water and slaking forces. The results indicate that the mono- and diesters compounds had disappeared in the Apl layer of fertilized corn, whereas these compounds were still present under unfertilized corn, sod and wooded areas. From a practical viewpoint, the results suggest that under natural conditions, soil aggregates (dry or wet) may be more affected by the dispersive and dissolution action of water than by slaking forces caused by air entrapment following sudden rewetting.

ISSN:0144-8765    

DOI:10.1080/01448765.1995.9754744

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Pestoban is a mixture of three plant extracts, only two of which (Cedrus deodaraandAzadirachta indicaoils) show toxicity against each of the snail species under test. The third (Embelia ribes) is non-toxic, but when all three are mixed, the toxicity of the mixture is 103time more active than either of the two toxic components.

ISSN:0144-8765    

DOI:10.1080/01448765.1995.9754745

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Atmospherically-derived nitrogen can be a major source of nitrogen in organic or other low-input farming systems. It is, however, in practice difficult to quantify the contribution of nitrogen from the atmosphere especially when dealing with grass-clover leys in the crop rotation. In this study a simple model based on knowledge about the content of clover in herbage and the time after establishment is presented and calibrated to a range of production conditions in Denmark.

ISSN:0144-8765    

DOI:10.1080/01448765.1995.9754746

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

WhiteflyBemisia tabaci(Genn.) populations were studied for five weeks on cantaloup (Cucumis meloL. cv. Annanas F1) to which different fertilizers (organic and inorganic) had been applied. The unfertilized control, ammonium sulphate at 100 kg N/ha, layer poultry manure (13.6 ton/ha, containing 3.9% N and 1.8% P) and broiler poultry manure (10.8 ton/ha, containing 5.0% N and 1.6% P) treatments resulted in a population of immatures of 21.0, 17.0, 7.0 and 6.0 per cm2respectively, during five weeks. There were no significant differences in the populations between the control and the inorganic nitrogen treatments (P > 0.05), nor between the two types of poultry manure (P > 0.05). Populations were significantly lowered in the poultry manure treatments in comparison to the inorganic N and the control treatment (P < 0.05).

ISSN:0144-8765    

DOI:10.1080/01448765.1995.9754747

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

In the terai region of north-eastern Uttar Pradesh (NEUP) 25 species of aphids have been recorded as feeding upon a number of food plants and being available simultaneously for parasitisation byLysiphlebia mirzaiShuja-Uddin. However, only five species,viz., Hyalopterous pruni(Geoffroy),Macrosiphum (Sitobion) miscanthi(Takahashi),Melanaphis sacchari(Zehntner),Rhopalosiphum maidis(Fitch) andSchizaphis graminum(Rondani) were parasitised to varying degrees on seven food plant species. The natural parasitism of the aphid species feeding onPennisetum glaucumandSorghum bicolorwas higher than on other food plants. The highest extent of parasitisation was recorded onR. maidisfollowed byM. sacchariandS. graminumon one or other food plants. Significantly moreR. maidis/P. glaucumwere parasitised than any aphid and host plant combinations. The aphid hosts as well as the food plants significantly influence the degree of parasitism. The cereal crop habitat was highly preferred byL. mirzaiduring September to January when large areas in NEUP were cultivated with cereal crops that provided adequate host resources. Later on, its incidence decreased to zero level in April due to plant senescence which induces the aphids to migrate from the crop, prior to the crop being harvested.

ISSN:0144-8765    

DOI:10.1080/01448765.1995.9754748

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0144-8765    

DOI:10.1080/01448765.1995.9754749

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0144-8765    

DOI:10.1080/01448765.1995.9754750

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0144-8765    

DOI:10.1080/01448765.1995.9754751

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor