摘要:

AbstractComposition and content of polyphenols of lucerne leaf and stalk were investigated during growth depending on the time of season at one growth stage.(+)‐Gallocatechin, (–)‐epigallocatechin gallate, (–)‐epigallocatechin, (–)‐epicatechin, (–)‐gallocatechin gallate, gallic acid, gallotannin and shikimic acid were estimated by qualitative chromatographic analyses on Whatman Chromedia paper SG‐81. The content of some polyphenol groups was determined by quantitative analyses and amounts were found of 0.06 to 0.50%, gallic acid; 1.10 to 2.36%, gallotannins; 0.31 to 1.10%, catechins in the dry matter of lucerne depending upon growth stage and cuts. Polyphenoloxidase activity from 7.80 to 18.70 units was established in the i

ISSN:0022-5142    

DOI:10.1002/jsfa.2740231002

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractTannic substances were isolated from dehydrated lucerne meal and it was found that they contained free gallic acid, gallotannins and flavanols. In the procedure for their isolation, cation and anion exchange resins, Amberlite IR‐120 and Amberlite IR‐45, were used. The isolated tannin was tested as an inhibitor of tryptic digestion of casein,L‐amylolytic digestion of starch and lipase enzymes. Inin vitrostudies it was found that the isolated tannin has a high inhibitory action on digestive en

ISSN:0022-5142    

DOI:10.1002/jsfa.2740231003

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractMetabolites of the alimentary tract of mice fed 0.5 and 4.0% of lucerne tannin isolate in an artificial diet were studied. Twelve identified and four unidentified substances were detected by paper chromatography on Whatman Chromedia paper SG‐81, coated with silica gel, using the solvent system 1‐butanol‐acetic acid‐water. 3‐Methoxy‐4‐hydroxybenzoic acid, 5‐o‐methylgallic acid, (–)‐epigallocatechin gallate, (+)‐gallocatechin and (–)‐epicatechin were found in greater amounts and 3,4‐dihydroxycinnamic acid, 3,4‐dimethoxy‐5‐hydroxybenzoic acid,m‐digallic acid,m‐hydroxycinnamic‐acid,m‐hydroxyhippuric acid and (–)‐gallocatechin gallate in smaller ones in faeces of mice fed on the diet containing 0.5 and 4.0% of tannin. These constituents were detected in traces or were not detected at all in faeces of mice fed on the diet without tannins. The main metabolites of the alimentary tract of mice on synthetic diet werem‐hydroxylc

ISSN:0022-5142    

DOI:10.1002/jsfa.2740231004

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractOne‐year‐old plants of lucerne were grown through two first‐flower harvests in growth chambers set at 35/29, 28/22, 21/16 and 16/10 °C day/night temperatures with and without N and K fertilisation. Time to first flower decreased from 50 to 17 days as temperatures increased. Averaged over all fertility levels, shoot heights; shoot numbers; and yields of leaflets, stems, herbage, roots and total plant decreased as temperatures increased. Neither N nor K materially affected these growth measurements, with a few exceptions. Averaged over all fertility levels, concentrations of P, K, Fe, B, Cu and Zn in the herbage, and all N fractions in the leaflets, stems and herbage, decreased as temperatures decreased; Ba, Sr and total non‐structural carbohydrates (TNC) increased; Ca changed very little; while Mg, Na, Al and Mn were variable. Neither N nor K affected the percentages of most minerals. However, N and K increased herbage Mg and K percentages, respectively. N increased all N fraction percentages, but K had little effect on them. K did not affect TNC percentages, but N decreased them in the herbage at 35/29 and 28/22 °C and in the roots at

ISSN:0022-5142    

DOI:10.1002/jsfa.2740231005

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractAnalyses of 80 samples of wheat showed a mean mercury content of 8 ng/g, with a range of 4 to 18 ng/g (ng = 10−9g). Wheat flour contained the same amount of mercury as wheat. Other cereals and oilseeds contained 4 to 29 ng/g of mercury. Levels of mercury varied for other organic materials analysed.The analytical method used is relatively rapid and simple when certain precautions are followed. The method consists of an oxygen‐bomb combustion of samples, reduction of the mercury in the bomb washings to elemental mercury and then analysis of the mercury by cold vapour atomic absorption spectrophotometry. The limit of detection of the method is approximately 1 to 2 ng of mercury/g of sample. The reliability of the method was verified by quantitative recoveries of added organic and inorganic mercury compounds from wheat and barley and by carrying out collaborative te

ISSN:0022-5142    

DOI:10.1002/jsfa.2740231006

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractThe effect of three nitrogen sources on the chemical composition of seven fungi, namely:Aspergillus niger, A. luchuensis, Penicillium crustosum, Alternaria tenuis, Rhizoctonia solani, Mucorsp. andPythium irregularehas been studied. The various fungi showed a great variation with respect to lipid percentage and total lipid content. Lipid content varied from 3.2 to 41.5%. Non‐polar lipids were comprised of monoglycerides, diglycerides, free sterols, free fatty acids and triglycerides. The quantitative make‐up of the non‐polar lipid varied with different nitrogen sources. Palmitic, stearic, oleic and linoleic acids were the major fatty acids while lauric, myristic, palmitoleic, linoleic and arachidic were the minor ones. The fatty acid composition was dramatically changed by changing the nitrogen source. Since different fungi responded differently to changes in nitrogen source, no generalisation could be made.Two‐dimensional thin‐layer chromatography of the polar lipid fraction of these fungi revealed the presence of a maximum of fifteen spots. Phosphatidyl choline, phosphatidyl ethanolamine and phosphatidyl inositol were the major spots while lysophosphatidyl choline, lysophosphatidyl ethanolamine and phosphatidyl glycerol were present in smaller quantities. In comparison to phospholipids, glycolipids (except sterol glycoside) were present in relatively lower concentration.Pythium irregularewas very characteristic in having no glycolipi

ISSN:0022-5142    

DOI:10.1002/jsfa.2740231007

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractThe relationships between concentration and subjective intensity of (a) sweetness and (b) bitterness have been separately determined and the effect of each on the subjective intensity of the other has been evaluated. The depression of sweetness by bitter additives, or bitterness by sweet additives obeys a simple mathematical relationship which may be used to calculate the “true” sweetness of a bittersweet sugar. This facilitates the structural explanation of sweetness in model sug

ISSN:0022-5142    

DOI:10.1002/jsfa.2740231008

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractA study was made, partly in a pilot scale bakery and partly in industry, of some aspects of the process for making cream crackers. It was shown that the conditions of formation of the initial dough sheet before lamination had a significant effect on the thickness of the finished crackers. This property was also shown to depend to an appreciable extent upon the humidity of the atmosphere in the first section of the travelling oven used to bake the crackers.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740231009

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractAn investigation has been made of the cracker making properties of a number of flour samples milled from different wheats. It has been shown that there is a strong interaction between flour properties (principally the flour protein content) and the processing conditions. The best cream crackers, as judged by the separation of the laminations and general appearance, were produced from flours of protein content 10.5 to 11.5%.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740231010

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY

摘要:

Abstract“Cell fragility” homogenates of fish with high pH look pale, not flocculent like those of normal fish or fish with low pH. The optical density of the homogenates of fish can therefore vary widely according to the pH and this fact severely limits the usefulness of the cell fragility method for investigating the changes brought about by cold storage.By the use of dilute buffers it was shown that the pH effect is caused by a high pH alone and not necessarily by any concomitant protein depletion. The effect can be reversed in the same piece of fish by soaking in a buffer at the opposite end of the pH scale.Photomicrographs showed that at high pH values the myofibrils tend to burst open, releasing protein into the surrounding fluid and it is suggested that if this protein could be coagulated the cell fragility method might still give useful results from high‐pH

ISSN:0022-5142    

DOI:10.1002/jsfa.2740231011

出版商:John Wiley&Sons, Ltd    

年代:1972

数据来源: WILEY