摘要:

AbstractFor centuries, diverse plant and animal materials have been fermented by various bacteria, yeasts, and fungi to make excellent foods. The kinds of micro organisms used in traditional fermentation are restricted to a relatively few genera, includingAspergillus,Rhizopus,Mucor,Actinomucor,Monascus,Saccharomyces,Neurospora,Acetobacler,Bacillus, andLactobacillus.The two principal advantages of food fermentations over other processes are to add flavor and to prevent spoilage. Fermented fish is a common food in the Orient and may have been the first product made by fermentation. Flavor is especially important in vegetable diets based on bland foods such as rice. Shoyu is the best, known oriental food fermentation, and it is very widely used as a flavoring agent. Be sides this fermentation, there are a large number of additional ones not so well known outside the Orient, whose products serve as seasoning or flavoring agents. Miso and natto are prepared from soybeans in Japan. Sufu is a cheese like product made from soybean milk in China. Tempeh and ontjom are Indonesian foods prepared from soybeans and peanuts, respectively. These food fermentations are discussed with emphasis on how they are produced and the flavor formed.

ISSN:0006-3592    

DOI:10.1002/bit.260090302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

ISSN:0006-3592    

DOI:10.1002/bit.260090303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractVarious biochemical transformations involved in vinous fermentations are reviewed from the point of view of their formal ion of volatile aroma or flavor compounds in fermented beverages. In addition to the recently elucidated processes for the formation of aliphatic primary alcohols of molecular weight greater than that of ethanol, Nordström's mechanism for the formation of esters during fermentation is discussed. Experimental evidence supporting this mechanism in vinous fermentation is presented; the White Riesling grape is found to contain insignificant, quantities of esters while the wine prepared from these grapes, analyzed immediately after fermentation, shows relatively large amounts of several volatile esters. In addition, in an investigation of an older California sherry, ethyl acid malate is found to be nearly all the single isomer with the hydroxyl group on the carbon adjacent, to the free carboxyl group. This finding suggests an enzymatic (presumably vinous fermentative) production rather than simple chemical esterification in the wine after fermentation. An extension of Nordström's mechanism for ester production is proposed to explain the formation of certain secondary amides found in wine

ISSN:0006-3592    

DOI:10.1002/bit.260090304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractGeosmin, an earthy smelling substance, has been obtained from several actinomycetes in addition to those previously reported. On the basis of the NMR and mass spectra of geosmin and its acid transformation product, argosmin, tentative partial structures have been proposed for both.

ISSN:0006-3592    

DOI:10.1002/bit.260090305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractA process for manufacturing disodium 5′‐guanylate was devised. 5′‐Amino 4‐imidazole carboxamide riboside (AICA‐R) was accumulated with an amount over 100 times those reported in the literature by fermentation ofD‐glucose with a non‐exacting purineless mutant derived from Bacillus megaterium JAM 1245) by x‐ray irradiation. The influence of RNA, amino acids, and salts on AICA‐R accumulation was clarified. Appropriate aeration and agitation was found necessary. The (60‐hr, cultivation of the medium containing 8% ofD‐glucose gave AICA‐R in the concentration above, 11 g/l. AICA‐R thus accumulated was separated from the fermentation broth by ion‐exchange technique and subjected to synthetic processes to yield disodium 5′‐guanylatc with th

ISSN:0006-3592    

DOI:10.1002/bit.260090306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractSome of the problems involved in the scale‐up of enzyme isolation procedures have been examined. In particular the isolation of prolyl‐tRNA synthetase has been investigated. Using a modified procedure (500 × laboratory scale) the enzyme has been separated from 25 kg. of Phaseolus aureus (mung bean) and Partially purified by acid precipitation followed by fractional precipitation with ammonium sulfate. The yield of enzyme was 42 g. (10.5% recov

ISSN:0006-3592    

DOI:10.1002/bit.260090307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractThe design and operational characteristics of a sell‐priming aerator are described. The aerator works without a compressor. H sucks the desired air quantity into the tank and distributes it, uniformly and in very fine bubbles over a certain cross‐section. The design and operational characteristics of a mechanical defoamer are described. The defoamer is mounted to the top of the fermentation tank and separates foam by centrifugal force into air and liquid. It is capable of handling foams of different composition and quality without, the addition of anti foam agents. Using submerged vinegar fermentation, production of baker's yeast., and industrial waste, water treatment as examples, the performance of aerators and defoamers of different, sizes is discus

ISSN:0006-3592    

DOI:10.1002/bit.260090308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractMannitol has long been known as a product of glucose metabolism by some strains ofAspergillus. Apparently no concerted effort, has been made to develop a practical fermentation process to make mannitol. Work at the Northern Laboratory has shown that nearly all strains of whiteAspergillusproduce significant amounts of mannitol; many strains of blackAspergillusalso have this characteristic.Aspergillus candidusNRRL 305 is an exceptionally good mannitol producer. Studies on a fermentation process were conducted in 20‐1, stainless steel fermentors, without baffles. Czapek‐Dox medium, modified by addition of corn meal, yeast extract, and enzymatically hydrolyzed casein was the most satisfactory medium tested. Suitable increments of glucose were fed daily to the fermentors. The duration of the fermentation was from 10 to 16 days. The effects of agitation, aeration, temperature, and pH of the medium were studied. Under optimal conditions yields of mannitol approached 50% of the glucose consu

ISSN:0006-3592    

DOI:10.1002/bit.260090309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractThis paper deals with a theoretical study on the dynamic, character of the chemostat system. It. is primarily based on the Monod model for growth limitation, although certain more complex models are considered. Since the Monod model is described in terms of two variables, an analysis by use of a phase plane plot will show the various possible types of behavior theoretically expected for transient conditions of the system. In this paper it will be shown that the chemostat system might show an overshoot (or an underswing) with respect to changes in cell and substrate concentrations, depending on the extent to which the system might be disturbed from steady‐slate conditions. Other types of transient behavior ran also be expected when one of the system parameters such as dilution rate or input substrate concentration is disturbed in a stepwise manner. The simple Monod chemostat model was found never to oscillate in either a damped or a sustained manner as has been experimentally reported. Discussion is included about the transient behavior of other chemostat models such as that involving a variable yield coefficient, i.e., including the effect of cell maintenance requirement

ISSN:0006-3592    

DOI:10.1002/bit.260090310

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractThe kinetic behavior of heterogeneous microbial populations was studied in a continuous flow completely mixed reactor operated at various dilution rates. Glucose was used as the growth‐limiting nutrient. The physiological growth parameters for cells harvested from continuous flow reactors were determined using batch experiments. It, was found that the growth parameters, maximum growth rate (μm), saturation constant (ks), and cell yield (Y) vary for each dilution rate, and cannot be considered as precise constants in depicting the kinetic behavior of heterogeneous populations. In addition, it was found that the yield coefficients obtained from batch experiments were always lower than those obtained from continuous flow experiments. Levels of substrate and biological solids calculated for different dilution rates using growth constants from batch experiments did not agree with the experimental values observed in steady‐state experiments. However, when the yield values from, the continuous flow experiments were used in conjunction with batch values for μmandksthe theoretical and experimental dilute‐out curves agreed fairly closely (within the range needed for engineering prediction) until the culture began to wash out of the unit. In general, the data substantiated the use of the single phase relationship between growth rate and substrate concentration described by the Monod equation, μ = μ

ISSN:0006-3592    

DOI:10.1002/bit.260090311

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY