摘要:

AbstractJuice from fresh, pulped, leaves is freed from most of the starch grains, fibre and detritus and coagulated quickly with steam. The protein coagulum is filtered off, washed with water at pH 4 and pressed into blocks with 30–40% dry matter. In this form it keeps under refrigeration.Texture, colour and nutritive value of the final product are determined by the conditions of drying. The precautions needed during drying, especially freeze‐drying, are described. The products are fairly stable at room temperature but lipids have to be removed before the protein will keep permanently. The conditions for doing this by acetone extraction are described.The composition of the protein and the uses to which it can be put are described brie

ISSN:0022-5142    

DOI:10.1002/jsfa.2740120101

出版商:John Wiley&Sons, Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractLeaf protein concentrates were tested as sources of supplementary protein in the diets of growing chicks and growing rats. Provided that the method of drying did not involve high temperatures, products made from mixed grasses, kale, barley leaves, rye leaves, and tares were all of uniformly high value, being similar to soya‐bean meal as protein sources. When drying was carried out in a forced draught oven, the temperature zone within which there was damage to the nutritive value of the protein was 82° to 9

ISSN:0022-5142    

DOI:10.1002/jsfa.2740120102

出版商:John Wiley&Sons, Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractA protein concentrate made from wheat leaves, and dried by a commercial process, was tested as a source of supplementary protein in practical diets for newly‐weaned pigs based on a 2:1 mixture of barley meal and millers' offals. When about 7% of dried leaf protein concentrate was included in the diet the rate of growth and the efficiency of utilisation of feed by the pigs were as good as when the diet contained 8% of white fish meal, the two diets being roughly equivalent in their contents of total and supplementary protein. When the content of dried leaf protein concentrate was raised to 10%, or higher, there was no better growth but the efficiency of utilisation of feed was significantly improved. Inclusion of a small amount (4.5%) of dried leaf protein concentrate in a diet otherwise deriving its supplementary protein from groundnut meal, promoted as good growth and as high an efficiency of utilisation of feed as with high levels of leaf protein concentrat

ISSN:0022-5142    

DOI:10.1002/jsfa.2740120103

出版商:John Wiley&Sons, Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractExtracts were made from the fresh leaves of 60 tropical species by mincing them and squeezing the resultant pulp through cotton cloth. Total‐N and protein‐N determinations were made on the extracted juice, and the percentages of total N and protein N extracted and total N remaining in the fibre were calculated. Small samples of crude protein were precipitated from the sap at 80° and analysed for total N.The results are classified according to the extractability of protein N from the leaf and to the protein content of the product isolated. The legumes, most of which were specially grown, were the best sources of easily extractable and good quality protein, but good results were also obtained with a few of the more common weeds, which in general yielded more protein than the leaves from existing crops. Leaves of some species contained much mucilage or fibre, and it was difficult to make adequate extracts from them by the method descr

ISSN:0022-5142    

DOI:10.1002/jsfa.2740120104

出版商:John Wiley&Sons, Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractUnder the conditions described the determination of calcium in the presence of an equivalent amount of magnesium, using Cal‐red as indicator, could tolerate up to 2.0 mg. of iron, 1.0 mg. of manganese, 3 mg. of aluminium and up to 6 mg. of phosphate in 50 ml. of solutio

ISSN:0022-5142    

DOI:10.1002/jsfa.2740120105

出版商:John Wiley&Sons, Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractThe acetone‐soluble lipids of red clover (T. pratense) consist largely of the galactolipids, galactosyl‐1‐glycerol and digalactosyl‐1‐glycerol linolenate. The fatty acids from the galactolipids, expressed in moles, were shown by gas‐liquid chromatography to consist of 95.8% linolenic, 1.9% linoleic and 2.3% palmitic acid. Oleic, stearic and palmitoleic acids were not detected. No indication was obtained of the presence of triglycerides in the acetone‐s

ISSN:0022-5142    

DOI:10.1002/jsfa.2740120106

出版商:John Wiley&Sons, Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractExamination of the lipids soluble in acetone at 0° from the leaves of rye‐grass (Lolium perenne), cocksfoot (Dactylis glomerata), white clover (Trifolium repens) and rape (Brassica napusL.) shows that the yield of fatty acids from these sources when corrected for unsaponifiable matter ranges from 70.5 to 76.5% as compared with 95.6% required for a pure triglyceride calculated as trilinolenin. Further investigation of the cold acetonesoluble lipids of rye‐grass by diffusion in light petroleum through a rubber membrane showed that as in the red clover leaf lipids examined by Weenink1most of the fatty acids were combined in a non‐dialysable form as galactolipids. These results support the view that glycerides do not occur to any appreciable extent in leaves but are replaced by galactolipids.Fatty acid analysis showed marked differences between the dialysable lipids (comprising 28.7% of the total acetone‐soluble fraction) and the non‐dialysable lipids in which the linolenic acid is largely concentrated, forming 88% of the total f

ISSN:0022-5142    

DOI:10.1002/jsfa.2740120107

出版商:John Wiley&Sons, Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractDipping potato chips in a solution of metabisulphite of concentration 0.5–1.0% (w/v) at pH 5.3–6.0 was the most effective treatment for retarding enzymic browning. Temperature had a direct influence on storage life: at 5° chips could be stored for 7 days and at 1° for 14 days.Dipping potatoes in metabisulphite solutions caused no immediate loss of thiamine, but there was a loss of 24% of the vitamin in 3 days during storage at 5°. Losses up to 30% may be experienced when sulphited raw potatoes are boiled immediately, compared with about 15% for untreated tubers. Frying potato chips normally results in a loss of about 10% of thiamine, and if dipped in sulphite solution a loss of 35–45% occurs which increases to 75% after 30 min. on a h

ISSN:0022-5142    

DOI:10.1002/jsfa.2740120108

出版商:John Wiley&Sons, Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractThe uptake of sulphur dioxide by peeled potato tissue when treated in various ways with a solution of sodium metabisulphite has been determined.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740120109

出版商:John Wiley&Sons, Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractThe prevention of enzymic browning of potato chips, by inactivation of the phenolase enzyme by heat, has been investigated. The relative merits of scalding by water, by infrared radiation and radio‐frequency power have been evaluated. A major disadvantage of these methods was the production of off‐flavours during subsequent storage. Microbial growth was also a serious problem, but could be controlled by scalding in the package or by irradiation after packag

ISSN:0022-5142    

DOI:10.1002/jsfa.2740120110

出版商:John Wiley&Sons, Ltd    

年代:1961

数据来源: WILEY