摘要:

AbstractThe solvent action of 0.255N‐, I.5N‐, 3N‐ and 6N‐sulphuric acid on Kikuyu grass and Rhodes grass, ‘feed’ and ‘faeces’, and of I‐5N‐sulphuric acid on Russian comfrey,Setaria splendida, andTrifolium semipilosum, has been studied. Equations have been derived to relate the ‘crude fibre’ remaining after acid digestion to the concentration of the acid and to the duration of the boiling. Experimental results are discussed in the light of Hallsworth's suggestion that the ‘crude fibre’ in animal feeding stuffs might best be determined by an acid digestion for I h. with either 5 or 7–5% sulphuric acid. The extraction of fats from the feeding stuffs beforehand, and the estimation of the nitrogen contained in the residues resisting

ISSN:0022-5142    

DOI:10.1002/jsfa.2740090101

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractA rapid method has been developed in which nitrogen, phosphorus, potassium, calcium, sodium and magnesium are determined in a single solution, obtained by digesting plant material with sulphuric acid and selenium. The analysis can be conducted with an error not exceeding 5%.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740090102

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractThe effects of in‐package desiccation on compressed and uncompressed dehydrated cabbage stored at 37° have been compared. The rate and extent of water loss from, compressed cabbage was rather less than from uncompressed material, but the rate of deterioration of uncompressed and compressed material appeared to be generally similar. Desiccation reduced the rate of deterioration in flavour, texture and ascorbic acid content, as well as in colour. For a three‐ to four‐fold increase in storage life, the sacrifice of space to desiccant is about 5% in the case of uncompressed dehydrated cabbage, and about 20% for compressed ma

ISSN:0022-5142    

DOI:10.1002/jsfa.2740090103

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

ISSN:0022-5142    

DOI:10.1002/jsfa.2740090104

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractBrewers' spent grain has been dried by through circulation of hot air in single layers and in beds up to 8 in. in depth.The effect of air temperature (100–220° F) and velocity (6.63–22‐2 lb. of dry air/sq. ft./min.) on the drying rates of single layers has been studied. It has been found that the drying rate is proportional to the total moisture ratio of the layer, and that both temperature and velocity have a marked effect on the proportionality constant.A method of predicting drying times in deep beds, based on the results of the single‐layer tests, is proposed and discussed. The accuracy of this method has been checked against actual drying times in deep beds and found to be within +‐11.5%.The resistance of deep beds to the passage of air has been investigat

ISSN:0022-5142    

DOI:10.1002/jsfa.2740090105

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractThe rate of drying of single layers of sugar beet cossettes has been found to vary markedly with temperature of the drying air from 140 to 220° F, and to increase slightly with a fourfold increase of air velocity, while humidity changes have little effect. The rate of drying is proportional to the total moisture content of the cossettes.A method of predicting the rate of drying of cossettes in beds up to 9 in. deep is given, for air velocities in the range 6–21 lb./sq. ft./min., for temperatures of 140 to 220° F, and humidities up to 40% R.H. The accuracy of the method is shown to be within +‐15%.Observations have also been made on the variation of internal temperature with change of moisture content and air temperature, and on the evidence of carameliz

ISSN:0022-5142    

DOI:10.1002/jsfa.2740090106

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractEstablished plots of four perennial grass species, rye‐grass (two strains), meadow fescue, timothy and cocksfoot were dressed with a balanced fertilizer at the rate of 0, 2 and 4 cwt./ acre at the start of the growing season and after each cut at the height of 8–10 in. The soluble carbohydrate (free hexoses, sucrose and fructosan) and the crude protein contents of the grass at each cut were determined and estimates of the yield of dry matter recorded.Increasing the amount of fertilizer led to (a, an increase in the weight of dry matter per acre and the number of cuts taken, (b, an increase in the protein content and the average weight of protein per acre at each cut and (c) a decrease in the content of soluble carbohydrates, particularly the fructosan fraction. The average weight of soluble carbohydrates produced per acre at each cut was least at the highest rate of fertilizer application. The stimulating effect of fertilizer appeared therefore to result in the utilization of sugars for leafy growth at the expense of carbohydrate storage in the form of fructo

ISSN:0022-5142    

DOI:10.1002/jsfa.2740090107

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractExamination of steam distillates from tea leaves showed that the amount of KMnO4‐oxidizable constituents decreased during the fermentation process. Methanol was present in the distillate and its content was greatly increased by steam distillation from acid or alkaline solution. The methanol present is attributed to hydrolysis of pectin in the leaf by the acid or alkali, or by enzymes in the leaf in neutral distillations. The amount of methanol is present in the distillate in amounts far in excess of those of the substances responsible for the tea arom

ISSN:0022-5142    

DOI:10.1002/jsfa.2740090108

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractFermenting tea leaf produces methanol as the result of enzymic demethylation of pectins contained in the leaf. The enzyme concerned (which was isolated and purified) is very similar to pectin‐methylesterases found in other plants.The activity of tea pectin‐methylesterase is partially inhibited by tea catechins and their oxidation products, but nevertheless a continuous demethylation process gives rise to pectic acid during the course of fermentation. In one particular case, a leaf mass exceptionally rich in pectin and pectase gave indications of gel formation.The significance of the pectic acid formed during tea ‘fermentation’ is di

ISSN:0022-5142    

DOI:10.1002/jsfa.2740090109

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractBy initially withholding the oxygen supply to fermenting leaf, thus allowing the process of formation of pectic acid by pectin‐methylesterase actions to proceed unhindered, it has been possible to demonstrate a reduction of oxygen uptake when the oxygen supply is restored. Addition of pectin to tea leaf both reduces oxygen uptake during fermentation and yields tea reported by tea tasters as under‐fermented. It is concluded that there is strong presumptive evidence that the rate of fermentation of Ceylon tea is in some degree regulated by the pectic substances and enzymes which occur in the l

ISSN:0022-5142    

DOI:10.1002/jsfa.2740090110

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY