scholarly journals The Hydrolysis of Maltose by Hydrochloric Acid under the Herzfeld Conditions of Inversion

1914 ◽  
Vol 6 (4) ◽  
pp. 413-416 ◽  
Author(s):  
A. J. Kluyver ◽  
William A. Davis
Keyword(s):  
Citric Acid ◽  
Hydrochloric Acid ◽  
Plant Extracts ◽  
Cane Sugar ◽  
Hydrolysis Of

It is shown that contrary to the statements of Kluyver and others, maltose undergoes slight hydrolysis (to the extent of about 2% when 1% solutions of maltose are used) when heated with hydrochloric acid under Herzfeld conditions. It is preferable therefore to adopt 10% citric acid, under the conditions formerly laid down, in estimating cane sugar in plant extracts when maltose is likely to be present.

scholarly journals A Study of the Methods of Estimation of Carbohydrates, especially in Plant-extracts: A New Method for the Estimation of Maltose in presence of other Sugars.

1913 ◽  
Vol 5 (4) ◽  
pp. 437-468 ◽  
Author(s):  
William A. Davis ◽  
Arthur John Daish
Keyword(s):  
Citric Acid ◽  
Plant Extracts ◽  
Sodium Acetate ◽  
Cupric Oxide ◽  
Quantitative Estimation ◽  
Gravimetric Method ◽  
Large Error ◽  
Cane Sugar ◽  
Accurate Estimation ◽  
Volumetric Methods

Certain sources of error encountered in the estimation of sugars in plant extracts are dealt with. Large errors in the gravimetric method may be obtained unless special care is taken in purifying the asbestos by boiling for at least 30 minutes with 20% sodium hydroxide. Weighing the reduced copper as cuprous oxide is likely to give rise to large error, and a process of weighing as cupric oxide, with certain precautions, is recommended.The volumetric methods of Ling and of Bertrand have been studied; the former is preferable in all respects to the latter, which we regard as only roughly approximate.In dealing with plant extracts, owing to the accumulation of sodium acetate in the solutions analysed, inversion by citric acid of lower concentration than 10% is generally incomplete. Inversion by invertase is, however, not interfered with by this salt. To estimate cane sugar inversion both by invertase and 10% citric acid is recommended. No loss of sugars occurs owing to the use of basic lead acetate as has been sometimes stated; the supposed loss is probably due to incomplete inversion caused by the presence of sodium acetate.It is shown by a detailed study of the action of dilute hydrochloric acid on different sugars that it is impossible completely to hydrolyse maltose at either 70° or 100° without simultaneously destroying large quantities of laevulose or dextrose.The only available method for the accurate estimation of maltose consists in the employment of special maltase-free yeasts, such as S. exiguus, S. marxiarnus or S. anomalus, introducing a correction (for pentoses, etc.) obtained by a special fermentation with baker's or brewer's yeast.6. A scheme for the quantitative estimation of sugars in plant material is given.

The Behavior of Lignin during Hydrolysis of Sweetgum Wood with Concentrated Hydrochloric Acid at Moderate Temperatures

Holzforschung ◽  
1981 ◽  
Vol 35 (6) ◽  
pp. 283-286 ◽  
Author(s):  
John Papadopoulos ◽  
Chen-Loung Chen ◽  
Irving S. Goldstein
Keyword(s):  
Hydrochloric Acid ◽  
Hydrolysis Of

Two-step demineralization of shrimp (Pandalus Borealis) shells using citric acid: An environmentally friendly, safe and cost-effective alternative to the traditional approach

2021 ◽  
Author(s):  
Julia Pohling ◽  
Deepika Dave ◽  
Yi Liu ◽  
Wade Murphy ◽  
Sheila Trenholm
Keyword(s):  
Citric Acid ◽  
Hydrochloric Acid ◽  
Environmental Health ◽  
Traditional Approach ◽  
Health And Safety ◽  
Cost Effective ◽  
Environmental Health And Safety ◽  
Pandalus Borealis ◽  
Chitin Extraction ◽  
Cost Effective Alternative

Removal of minerals from crustacean shells during chitin extraction is traditionally achieved using hydrochloric acid. However, the environmental, health and safety concerns of hydrochloric acid have led to investigation of...

Effect of pH, Acidulant, Time, and Temperature on the Growth and Survival of Listeria monocytogenes

1989 ◽  
Vol 52 (8) ◽  
pp. 571-573 ◽  
Author(s):  
KENT M. SORRELLS ◽  
DAVIN C. ENIGL ◽  
JOHN R. HATFIELD
Keyword(s):  
Antimicrobial Activity ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Listeria Monocytogenes ◽  
Citric Acid ◽  
Hydrochloric Acid ◽  
Malic Acid ◽  
Incubation Temperature ◽  
Growth And Survival ◽  
Ph Values

The effect of different acids, pH, incubation time, and incubation temperature on the growth and survival of four strains of Listeria monocytogenes in tryptic soy broth was compared. Hydrochloric acid (HCl), acetic acid (AA), lactic acid (LA), malic acid (MA), and citric acid (CA) were used to acidify tryptic soy broth to pH values 4.4, 4.6, 4.8, 5.0, and 5.2 pH. Incubation times were 1, 3, 7, 14, and 28 d at 10, 25, and 35°C. The inhibition of L. monocytogenes in the presence of high acidity appears to be a function of acid and incubation temperature. Based on equal pH values, the antimicrobial activity is AA > LA > CA ≥ MA > HCl at all incubation times and temperatures. When based on equal molar concentration, the activity appeared to be CA ≥ MA > LA ≥ AA > HCl at 35 and 25°C, and MA > CA > AA ≥ LA > HCl at 10°C. Greatest antimicrobial activity occurred at 35°C. Greatest survival occurred at 10°C and greatest growth occurred at 25°C. Final pH of the medium was as low as 3.8 in HCl at 28 d. All strains grew well at pH values lower than the minimum previously reported (5.5–5.6).

scholarly journals Studies on enzyme action. IV.—The sucroclastic action of acids as contrasted with that of enzymes.

1904 ◽  
Vol 73 (488-496) ◽  
pp. 526-537 ◽  
Author(s):  
Edward Frankland Armstrong ◽  
Robert John Caldwell ◽  
Henry Edward Armstrong
Keyword(s):  
Cane Sugar ◽  
Enzyme Action ◽  
Milk Sugar ◽  
New Instrument ◽  
Hydrolysis Of

Not only are the various bioses hydrolysed at very different rates by enzymes but they are also known to differ in their behaviour towards acids: cane sugar being hydrolysed with the greatest facility, whilst maltose is acted upon but slowly. The experiments described in this communication were instituted primarily with the object of ascertaining the behaviour of milk sugar, of which nothing was known. The hydrolysis of cane sugar under the influence of acid was carefully investigated by Wilhelmy as far back as 1850, with the aid of the polariscope, then a new instrument.

Kajian potensi limbah tulang sirip Ikan Tuna (Thunnus Sp) sebagai sumber gelatin dan analisis karakteristiknya

Jurnal Zona ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 50-57
Author(s):  
Dahlia Dahlia ◽  
Rahman Karnila ◽  
Yusni Ikhwan Siregar
Keyword(s):  
Hydrochloric Acid ◽  
Food Studies ◽  
Bone Collagen ◽  
Acid Solutions ◽  
Fishy Odor ◽  
Hydrochloric Acid Solutions ◽  
Hydrolysis Of

Gelatin is a protein from the hydrolysis of bone collagen and skin of animals wich are widely used for industrial food and non food. Studies on extraction of gelatin from tuna (Thunnus sp) bone were carried out by soaking in hydrochloric acid solutions of 4%, 6% and 8% for 48 hours respectivelly and extracted with aquadest at 60ºC, 70ºC and 80ºC for 5 hours. The extract was filtered with filtering cloth and the filtrate was oven dried at 55ºC for ± 48 hours until gelatin was formed. The result showed that soaking the bone in 8% hydrochloric acid solutions followed by extraction 80ºC for 5 hours gave the best result with 8,64 yield, isoelectrict point 8,20%, protein contain 93,72%, lipid contain 0,74-1,75%. Gel strengh 257,59 g/bloom gel strengh, viscosity 3,20 cPs, pH 3,98. The results obtained for water contain of 6,97%. Ash countain 2,07%. The colour of gelatin produced from tuna bone showered different with commercial gelatin that is between yellowish brown to whitish yellow. Gelatin made from tuna bone has fishy odor whereas commercial gelatin has neutral odor.

Sign in / Sign up

Export Citation Format

Share Document