+ Site Statistics
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Enzymatic determination of L-malic acid in honey

Food Chemistry 62(4): 503-508

Enzymatic determination of L-malic acid in honey

L-Malic acid determination has been carried out in honey using a direct enzymatic method. The sample solution was prepared from 2.5g honey in 100 ml Milli-Q water. The enzymatic determination was measured spectrophotometrically at 340 nm, using glutamate-oxaloacetate transaminase and L-malate dehydrogenase. The direct method combines precision (CV was 3.5%, at worst), good recovery (100 +- 3.5 %), zero interference, simplicity, and low cost (cost was reduced by 50% using a microtest). This direct enzymatic method was applied to 20 floral honeys of Galicia (northwestern Spain) and the results ranged between 94 and 596 mg kg-1 (mean 246 mg kg-1) of L-malic acid, which is in keeping with value ranges obtained by other authors. Different clarifications (as polyvinyl-polypyrrolidone (PVPP), Carrez, Carrez with NaOH, Carrez with KOH, Carrez together with PVPP and activated charcoal) and a pair of controls have also been used but the precision and the recovery of direct enzymatic method of L-malic acid in honey did not improve. To study the interaction of beta-lactoglobulin (BLG) with flavour compounds a fast screening methodology was developed. BLG (variant AB, pure A and pure B) was immobilized onto a silica support, filled into a column and combined with a HPLC-system. A total of 24 different flavour compounds were injected and their retention times determined at different pHs and protein concentrations. The binding constant for each compound was calculated from the retention times and the protein concentration of the column. This simple system allows the rapid screening of many flavour compounds under a variety of external conditions like pH, salt content and flavour concentration. This procedure also permits the study of competitive effects with several flavour compounds in the solution.

Accession: 003127003

DOI: 10.1016/s0308-8146(97)00166-0

Download PDF Full Text: Enzymatic determination of L-malic acid in honey

Related references

Nordmann, R.; Arnaud, M.; Nordmann, J., 1963: Enzymatic Determination Of Blood L-Malic Acid. In the normal human, the concentration of L-malic acid in total blood (1,173 [plus or minus] 0,270 [mu]imoles/100 ml) is of the same order of magnitude as that of [alpha]-ketoglutaric acid. The distribution of L-malic acid between plasma and eryth...

Bergner-Lang, B., 1977: Observations on enzymatic citric acid and L malic acid determination in wine. Deutsche Lebensmittel Rundschau: 73 (9) 279-280

Beutler, H.O.; Wurst, B., 1990: A new method for the enzymatic determination of D-malic acid in foodstuffs. A decarboxylating D-malate dehydrogenase with high activity was obtained from a strain of Escherichia coli. The enzyme was produced with high purity and stability (loss of activity about 15% over 12 months at 4 degrees C) and was used to develop a...

Ohno, Y.; Nakamori, T.; Zheng, H.; Suye, S-ichiro., 2008: Reverse reaction of malic enzyme for HCO3- fixation into pyruvic acid to synthesize L-malic acid with enzymatic coenzyme regeneration. Malic enzyme [L-malate: NAD(P)(+) oxidoreductase (EC] catalyzes the oxidative decarboxylation of L-malic acid to produce pyruvic acid using the oxidized form of NAD(P) (NAD(P)(+)). We used a reverse reaction of the malic enzyme of Pseudo...

Puchades R.; Herrero M.A.; Maquieira A.; Atienza J., 1991: Simultaneous enzymatic determination of l levo malic acid and l dextro lactic acid in wine by flow injection analysis. A simultaneous determination of two organic acid species in wine by a flow injection analysis method using enzyme-immobilized open tubular reactors is described. The design of the optimal geometry of the FIA system is especially important to avoid...

Rosset, R.; Dupuy, P., 1958: Determination of acid 1-malic in fermented liquor by enzymatic de-carboxylation. A biologic method of dosage of this acid is proposed. It is a quite common ingredient in vegetables and a normal cell metabolite that is found in high concentrations in many fruits. Its importance is then primordial, in the constitution of fruit j...

Mayer, K.; Busch, I., 1963: On an enzymatic malic acid determination in wine and grape juice. Mitteilungen aus dem Gebiete der Lebensmittel-Untersuchung Un Hygiene 54: 60-65

Mohler, K.L.oser, S., 1969: Enzymatic determination of acids in wine. I. Malic-, Lactic- and citric-acid

Lonvaud-Funel, A.D.neche, B.B.euze, D., 1981: Continuous flux automation of the enzymatic determination of malic acid in wines. Connaissance de la vigne et du vinub1981) 4(4): 207-217

Sabatini, A.G.; Marcazzan, G.L.; Colombo, R.; Garagnani, M., 1994: Application of an enzymatic method for quantitative determination of formic acid and lactic acid in honey. The method, which is easy to use, involves the use of commercially available kits containing NAD and formate or lactate dehydrogenase for the determination of formic or lactic acid, respectively. Analyses of 42 samples of unifloral honeys (7 types...