摘要:

AbstractAnalyses of 42 sewage sludges from rural and industrial towns in England and Wales show very large concentrations of certain trace elements. Total contents of 5% Zn, nearly 1% Cr and Cu and 0.5 % Ni were found in certain dried sludges. Total contents of Cu, Sn and Zn and, to a lesser extent, Ag, Bi and Pb were much greater than the levels of these elements in soils. Total Cr and Ni were very high in a small number of samples. Acetic acid‐soluble Zn and Cu levels were generally very much greater than in soils. Overall, Mn, Ni and Zn had considerably higher percentage solubilities than Cr, Cu, Mo, Pb, Sn and V. Zinc, Cu and Ni appear to be the elements most likely to give rise to toxicity problems in plants due to the use of sewage sludge as a soil additiv

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230112

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractThe fermentation rate and carboxylic acids of Ogi, a Nigerian fermented cereal porridge, have been investigated. As a measure of fermentation rate, the acidity of steeped grain was evaluated by extracting the acids with a suitable solvent and titrating against a standard alkali. Since the method is time consuming, the titratable acidity of the aqueous centrifugate may be preferred in routine quality control operations. The carboxylic acids of Ogi fermentation were analysed using paper, gas‐liquid and thin‐layer chromatography. Eleven acids were identified, lactic, acetic and butyric acids being the most import

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230113

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractTwo feeding trials were carried out, the first to establish the optimum level of zinc in the diets of growing pigs reared in the tropical environment using essentially the locally‐produced feeding stuffs, and the second to investigate the effects of adding graded levels of lard to these diets on the performance characteristics of pigs and on the incidence of parakeratosis. The parameters investigated include daily gains, feed consumption, efficiency of feed utilisation and the appearance of parakeratotic lesions on the skin. Diets in trial 1 were supplemented with 0, 100, 200, 400 and 500 parts/million of zinc, while those in trial 2 were supplemented with four levels of zinc 0, 100, 200 and 300 parts/million and three levels of lard, 0, 2.5 and 5% in a 4 × 3 factorial experiment. The optimum level of zinc as established by trial 1 was 100 parts/million, the 300–500 parts/million zinc levels being detrimental, while with the addition of graded levels of lard in trial 2 these higher levels of zinc gave better performances as the lard levels increased. A direct relationship between lard level and zinc content of the diets was therefore established, the higher the level of lard in the diet, the greater was the level of zinc supplementation for optimum growth response and feed utilisation efficiency of young

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230114

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractVarious factors responsible for the extensive browning of dough prepared from the whole wheat meal flour of Mexican wheats have been investigated. The major factors determining this enzymic browning appear to be the high activity of tyrosinase and the concentration of free tyrosine and total phenols present in these wheats.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230115

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

ISSN:0022-5142    

DOI:10.1002/jsfa.2740230101

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY