摘要:

Starter culture fermentation of cocoa may become a novel approach to the effective utilization of some waste by‐products in the cocoa industry. Cocoa sweatings could be rapidly collected for use in food product development when some strains of yeasts are used as starter cultures for the fermentation. The action of the yeasts in degrading cocoa pulp which is 76–80% esterified to cocoa sweatings is most likely due to presence of polymethyl galacturonase, since pectin esterase activity was completely absent in all the yeast strains tested. The pectin content of the resulting cocoa sweatings could be used to regulate the period of sweating collection depending on its intended use in food product development.

ISSN:0890-5436    

DOI:10.1080/08905439609549958

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Summary

ISSN:0890-5436    

DOI:10.1080/08905439609549959

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Immobilized metal ion affinity chromatography (IMAC) enables the fractionation of commercial fungal enzyme preparations. Pectin‐lyase showed no affinity with the chromatographic matrix at pH 7. Endo‐glucanase and cellobiohydrolase were both eluted in almost all fractions but predominantly in three fractions when pH decreased. This suggests that IMAC can discriminate between different forms of cellulase isoenzymes. Polygalacturonase and pectinesterase were released with last fraction, showing their strongest affinity for the matrix. Following an experimental design, IMAC fractions containing separately pectin‐lyase and cellulase have been used to formulate an optimal enzymatic preparation for liquefaction of passion fruit pulp. It has been found that for every liter of passion fruit juice, at least 85 units of pectin‐lyase, 100 units of cellobiohydrolases and 700 units of endo‐glucanases are required for convenient liquefaction after 1 hour of incubation at 30 °C.

ISSN:0890-5436    

DOI:10.1080/08905439609549960

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Phycocyanin, a blue colorant from the cyanobacterium (blue green alga)Spirulina platensiswas evaluated for its safety as a natural food colour by toxicity evaluation studies in albino rats. Acute and subchronic studies on phycocyanin were conducted on both sexes of albino rats. Phycocyanin at high concentrations‐ 0.25 to 5.0 g/kg body weight (w/w) did not induce any symptoms of toxicity nor mortality of the animals. Feeding of low concentrations of phycocyanin at 0.5 to 4.0 g/kg in the diet for 14 weeks did not affect food intake or body weight gain of phycocyanin‐fed rats compared to control animals. Terminal values on absolute and relative weights of vital organs, hematology and serum enzymes did not reveal any differences between phycocyanin‐fed and control groups. Histological examination of vital organs did not show any remarkable differences between treated and control groups. Overall, consumption of phycocyanin, a natural colorant fromSpirulina platensisdid not result in adverse effects in experimental animals.

ISSN:0890-5436    

DOI:10.1080/08905439609549961

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Summary

ISSN:0890-5436    

DOI:10.1080/08905439609549962

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Because of their prebiotic properties, fructo‐oligosaccharides (FOS) that belong to inulin type are known to beneficially affect the host. Among eight commercial tested enzyme preparations, Cytolase PCL5 was found to possess the highest glycosyltransferase activity (7.4 U/ml and 0.17 U/mg proteins). Optimum conditions for FOS production from sucrose were found to be : pH 5.5, temperature 55°C and addition of 7 units of fructosyltransferase activity per gram sucrose. In presence of glucose (competitive inhibitor), the efficiency was 50% based the amount of sucrose consumed. Both HPLC and 13c_nmR spectrometry analysis indicated that synthetised FOS belong to neo‐FOS type (neo‐kestose, neo‐nystose and neo‐fructofuranosylnystose), a structure which is very close to inulin type (same linkage between fructosyl units).

ISSN:0890-5436    

DOI:10.1080/08905439609549963

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Sugar beet is an important crop cultivated widely in Europe. Roots contain up to 6–9 t/ha of fermentable sugar. Our laboratory is targeting to investigate the production possibilities of ethanol and levan byZymomonas mobilisbacteria, using sugar beet juice or their syrup as raw material. TheZ.mobilisstrain 113 “S”;, selected in our institute, produces simultaneously with ethanol up to 40–70 g/1 fructose polymer levan in sucrose medium. It was established thatZ.mobiliscan convert sucrose into ethanol and levan in batch fermentation using natural sugar beet diffusion juice, without additives of mineral salts and growth factors. Syrup obtained in sugar industrial production by conventional technology from diffusion juice after evaporation with 65% sucrose can be used also as raw material for medium preparation. Additives of N, P, K, Mg, as well as yeast extract, were shown to stimulate the culture growth and product synthesis on such media. Reuse of liquid fermentation products after separation of levan, and distillation of ethanol, can be applied for medium preparation. The medium osmolality increases in this case. Ethanol, levan and fructose production may have potential in the sugar production industry.

ISSN:0890-5436    

DOI:10.1080/08905439609549964

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

ISSN:0890-5436    

DOI:10.1080/08905439609549957

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor