摘要:

AbstractIn order to study changes in the composition, particularly the transformation of nitrogen compounds in composts and deep litter, reliable procedures were devised for the determination of total nitrogen, uric acid nitrogen and forms of nitrogen soluble in cold o.IN‐H2SO4in fresh sub‐samples. The experimental errors have been estimated for each stage of the nitrogen determinati

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100301

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractAn experimental study was made of the changes in composition and losses of organic matter and nitrogen (especially that soluble in cold o.IN‐H2SO4) occurring in composts prepared from cereal straw mixed with fresh poultry droppings in various proportions and stored for up to 3 years. A comparison was also made of composts prepared with droppings and with ammonium sulphate plus calcium carbonate, each at two levels of total nitrogen.Tests were made on composts prepared on a small scale kept under cover in brick cells and in large heaps.Loss of organic matter and changes in nitrogen components could be followed indirectly from the ratios of ash to loss on ignition and of ash or P or K content to nitrogen content.There was accumulation of NO3−‐N up to about 1% of the dry matter in composts stored for 2–3 years, the composition of the compost then being fairly stable and differing little whether a high or low proportion of droppings was used initially. The optimum ratio of straw to droppings was 1: 1.5 by weight.Composts made with ammonium sulphate and calcium carbonate in place of droppings had lower N, P and K c

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100302

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractA study is made of the enzymic oxidation of substrates isolated from the tea‐leaf. The results confirm that the phenolic oxidation products found in black tea originate either from (—)‐epigallocatechin or (—)‐epigallocatechi

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100303

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractWhen tea extracts are used as culture media forAspergillus niger, theaflavin gallate is converted into theaflavin, substances A and B into substance C, and one of the components of Q into substance R. Flavanol gallates are also converted into the corresponding flavanols. These changes arc probably all due to the action of an esterase developed by the mould, and indicate that theaflavin gallate and substances A, B and Q are gallic acid esters, as previously deduced.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100304

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractImproved methods are described for the preparation of theaflavin gallate and of theaflavin from black tea extracts Both substances were obtained chromatographically pure and the theaflavin was crystallized.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100305

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractThe drying characteristics of unscalded diced potato have been investigated in a laboratory through‐circulation dryer. The potatoes used in 1/4‐in. dice form had initial moisture content 75–85%.Shallow layers of the material were tested to find the effect of the following factors on the drying rate: scalding, shape of material (0.125–0.5‐in. dice), slice thickness (0.125—0.5‐in.), air flow (9–20 lb. of dry air/sq. ft./min.), temperature of air (120–220d F) and wet‐bulb depression (20–80d F).Deep beds of diced potato were similarly investigated and a prediction method based on the shallow‐bed tests applied to determine the drying times between moisture content limits of 5.0 to 0.1. This method gave an accuracy of 9.0%.Shrinkage of the material during

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100306

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractBoth shallow and deep beds of diced beetroot have been studied, variables investigated being D.B.T. (120–200° Ff); air flow (6–12 lb. of air/sq. ft./min.); W.B.D. (10–70° F), and bed‐loading (Ld= 0.21‐2.1 Ib. of B.D.S./sq. ft.).Drying rates in shallow beds were found to depend largely on the D.B.T., the W.B.D. and air‐flow rate having a less marked effect. A prediction method used to determine the drying times of deep beds of diced beetroot in the moisture content range 8 to 0.1 was applied and found to be accurate to ±M9.0%.Moisture distribution in a single slice of beetroot during drying has als

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100307

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractDetailed data collected during 1952–54 on the chemical composition of passion fruit juice (Passiflora edulis, Sims.) are presented and discussed. Figures are given for the distribution of apparent and true ascorbic acid in different fruit components at different stages of maturity and plant organs for the ascorbic acid and dehydroascorbic acid contents of normal juice, and for the carotene content of juices extracted from passion fruits at different stages of maturity.Passion fruit juice is one of the most nutritious fruit juices, being rich in easily digestible carbohydrates, ascorbic acid and carotene, a good source of nicotinic acid and riboflavin and a fair source of mineral matte

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100308

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractConcentrations of NH 4+‐N and NO 3−‐N in the surface (0–6 in.) layer of a light soil, with and without added nitrogen fertiliser, were measured from May to October 1957 on plots kept free of vegetation and those cropped with ryegrass.The application of nitrogen fertilisers to the soil increased the concentration of mineral nitrogen in the surface layer. On bare land the level of mineral nitrogen in the surface soil remained high until July when it was reduced by heavy and prolonged rain. NH 4+‐N from ammonium sulphate or urea was converted to NO 3−‐N slowly; 20 weeks were required to nitrify ail the added nitrogen.When established, ryegrass removed nitrate very rapidly from the soil and reduced the level of NO 3−‐N to<1 p.p.m. both on plots with or without fertiliser‐N. On plots dressed with ammonium sulphate there was a loss of NH 4+‐N under ryegrass and no corresponding increase in NO 3−‐N. The first cut of grass taken in July contained three‐quarters of the nitrogen applied as fertiliser; the second cut contained only one‐tenth of the amount applied.Examination of soil samples taken in October from depths up to 3 ft. showed no accumulation of mineral nitrogen under ryegrass, but there was a downw

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100309

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractThe volatile oil ofLeptospermum ericoideshas been shown by fractionation in an efficient column, to contain at least thirteen constituents. Eight of these have been identified with known compounds, namely, (+)‐α‐pinene, (+)‐β‐pinene, 1: 8‐cineole, dipentene, β‐terpinene, linaloöl, (+)‐α‐terpineol and (+)‐aromadendrene. Other constituents include a terpene alcohol, a sesquiterpene and a new

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100310

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY