摘要:

AbstractA determination of hydrogen cyanide in fresh cassava tissues and in processed cassava products using an alkaline picrate procedure and a pyridine‐pyrazolone method which uses Conway vessels has been made. Results obtained for the fresh cassava tissues by the two methods were similar. Statistically significant higher values for processed cassava products were obtained by the alkaline picrate method which measured both glycosidic and non‐glycosidic cyanide. The suggestion is reaffirmed that hydrogen cyanide in processed cassava products may exist in two forms: glycosidic and non‐glycosidic (entrapped) cy

ISSN:0022-5142    

DOI:10.1002/jsfa.2740360102

出版商:John Wiley&Sons, Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractThe influence of pH, time, temperature, cellulase treatment and washing conditions on the recovery of solids and protein from Australian wheat bran was investigated. Highest yields (83% of available protein, 72% of total solids) were achieved by extracting at pH 12 and washing with water at pH 7. However, acceptable yields could be obtained under near neutral conditions by extracting at pH 6.5 for 16 h followed by three washes at pH7. Under these conditions 72% of the protein and 55% of the total solids were extracted and greater stability of the vitamins thiamin, riboflavin and pyridoxine was expected. The use of cellulase in an attempt to disrupt the aleurone cell walls did not improve the recoveries of either protein or solids.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740360103

出版商:John Wiley&Sons, Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractAn assessment was carried out of the effects of an increase in the amount of fibre, as cellulose, and of a replacement of maize starch by potato starch in diets containing egg albumen as the sole protein, on the determination of true digestibility (TD) and biological value (BV). An increase in the fibre content of the diet at the expense of maize starch led to a rise in both fascal and urinary N excretion, with diets containing either 20 or 80 g egg albumen kg−1. However, the response of the rats to increasing fibre concentration in the diet was different for the two levels of protein probably due to differences in dry matter intake (DMI). It was found that the conventional method of estimating metabolic faecal nitrogen (MFN) was not adequate for diets of decreasing digestibility; TD decreased by 0.35% for a rise of 1% cellulose in the diet. A more accurate method of estimating MFN was derived from a relationship between the N in the faeces and the digestibility of the diet. The increase in urinary N excretion led to a decrease of 0.41% in BV for a 1% rise in the cellulose concentration of the diet. It appears, therefore, that the ratio of digestible to indigestible matter in the diet affects the determination of protein quality. The replacement of maize starch by potato starch in the diet caused an increase in faecal N excretion and a decrease in urinary N excretion until a level of 200 g potato starch kg‐1was reached. This affected the determination of TD and BV accordingly. An increase in the size of the caecum of the rats fed potato starch indicated that increased fermentation may have resulted in production of additional bacterial cells to be excreted in the faeces. Thus, both the amount of fibre and the type of starch in the diet affect the determination of protein qual

ISSN:0022-5142    

DOI:10.1002/jsfa.2740360104

出版商:John Wiley&Sons, Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractThere was a small decrease in grain yield (from 10.8 to 10.5 t ha−1) when wheat straw (3 t dry matter ha−1) was incorporated into a silty clay loam soil sown to winter wheat. In the absence of straw, 60% of autumn‐applied15N‐labelled nitrate was lost from the crop:soil system. Straw incorporation decreased this loss to 47%. There was little overall effect on the uptake of N by the crop, presumably because straw immobilised inorganic N that would otherwise have been leached from the soil during winter. Only 12% of the N in15N‐labelled straw was recovered by the crop; 78% still remained in the soil one year after inco

ISSN:0022-5142    

DOI:10.1002/jsfa.2740360105

出版商:John Wiley&Sons, Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractThe synthetic growth promoter diethylstilboestrol (DES) administered orally to pigs can be detected by radioimmunoassay (RIA) analysis of kidney, liver, faeces, bile and urine from animals fed continuously to slaughter, but not in muscle, fat or plasma. If treated animals are fed on material not containing DES for 72 h prior to slaughter, then the levels of parent compound and metabolite in all products decrease to become not significantly greater than those in control animals. The gross metabolism of DES in pigs and bovines appears to be similar.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740360106

出版商:John Wiley&Sons, Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractVarietal differences in the puffing characteristics of parboiled rice (PABR), parboiled milled rice (PAMR) and milled rice (MR) after storage in polyethylene bags (PLY), polyethylene impregnated jute bags and jute bags (JUB) for varying times up to 120 days were studied. Monthly observations covering changes in physicochemical properties considered to have bearings on the puffing characteristics of rice were made and the factors responsible for puffing of rice have been tentatively identified. Better puffing followed increased ageing of rice samples. PABR was a better puffer than PAMR while MR yielded charred rice and hence was unsuitable for puffed rice production. Alkali degradation and grain hardness had some regulatory effect on the quality of puffing of rice. PLY emerged as the best packaging material for storing rice for later puffing. In JUB rapid damage of rice samples occurred owing to insect infestation and it was the poorest packaging unit.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740360107

出版商:John Wiley&Sons, Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractHigh performance liquid chromatography was carried out to determine the soluble sugar content in canned soft drinks and commercial fruit juices stored in different types of containers. The total amount of sugars ranged from 9.2 to 13.5 g 100 ml−1for the soft drinks, 10 to 14 g 100 ml−1in fruit nectars and 3 g 100 ml−1in tomato juice. The individual sugar content of soft drinks varied between different batches, although the total amount remained fairly constant for each kind of drink or juice. Only in tomato juice where sucrose was not present, did the values for glucose and fructose remain con

ISSN:0022-5142    

DOI:10.1002/jsfa.2740360108

出版商:John Wiley&Sons, Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractEquations were derived for predicting starch and lipid content of pea varieties from near infrared data measured on a filter instrument (Technicon InfraAlyzer 400). The accuracy of the predictions were tested against separate data sets and were found to be better than ±2.6% for starch (range 20–45%) and ±0.3% for lipid (range 1.4–3.3%). Together with the previous work on the near infrared determination of protein it is possible to analyse rapidly for three components important to a plant breeding programme. The study has also demonstrated a clear‐cut delineation between round and wrinkled pea ge

ISSN:0022-5142    

DOI:10.1002/jsfa.2740360109

出版商:John Wiley&Sons, Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractA procedure is described for the extraction of sucrose, glucose and fructose from storage root vegetables. An automatic domestic pressure cooker containing a circular test tube rack holding 36 tubes was used for the extraction. All water soluble sugars were extracted in 30 min at 110°C. The method is at least as efficient as those using hot ethanol and methanol: chloroform:water and is significantly more efficient in its use of time and energy

ISSN:0022-5142    

DOI:10.1002/jsfa.2740360110

出版商:John Wiley&Sons, Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractWhole grain flours of two cultivars of pearl millet (Pennisetum typhoidesRich) were stored in cans for 8 days at the prevailing room temperature (25±5°C), until the flours developed an off‐flavour and bad taste. The flour samples were then evaluated for protein quality. The values of protein efficiency ratio, true digestibility, biological value, net protein retention and protein utilisation fell markedly during storage. The protein quality of the cultivar with the higher amount of oil was affected more sever

ISSN:0022-5142    

DOI:10.1002/jsfa.2740360111

出版商:John Wiley&Sons, Ltd    

年代:1985

数据来源: WILEY