Date Syrup Research Articles

STUDIES ON LIBYAN HONEYS

ABSTRACTTen honey samples representing various floral types were obtained from different areas in Libya. Two other samples were obtained from hives, where bees were fed on sugar syrup and date syrup, respectively. The chemical composition and some characteristics of these samples were studied. The data obtained generally showed that the specifications of honeys produced in Libya conformed with those required for table honey. The application of thin‐layer chromatography on cellulose‐coated plates for the analysis of honey sugars yielded clear resolution and discrete spots. Some measures — such as high level of calcium, low level of potassium and UV‐absorption spectra of honeys were suggested to be used for identifying the sugar‐honeys and for ensuring the quality of blossom honeys. An attempt has been made to predict the granulation behavior of honeys and a derived regression formula was suggested.

Libyan Date Syrup (Rub Al‐Tamr)

ABSTRACTRepresentative samples of date syrup were obtained from the local market and analysed. The chemical composition and some characteristics of these samples were investigated. The reducing sugars of the syrup comprised about 95% of its total sugars content. The major sugars present were glucose—48.70%, fructose‐45.21%, and sucrose—6.09%. Furthermore, the coloring matters of date syrup were isolated, separated and further investigated. It was concluded that the color groups, degradation products of reducing sugars, melanoidines, and iron‐polyphenolic complexes, contributed to the color of date syrup. The melanoidine‐type compounds, which comprised the major part of syrup colorants, showed a low selective adsorption tendency on both charcoal and anion resins. An efficient clarification of date syrup has been achieved by the use of calcium phosphate precipitation. The results obtained may be of help in devising industrial processes for the utilization of dates, abundantly grown in Libya, in the production of “Total invert liquid sugar” with multiple commercial uses of its own.

The use of deionised date syrup as a substrate for citric acid fermentation

Production of citric acid from date syrup by fermentation has been undertaken usingAspergillus niger as the producer organism. Poor yields were obtained when untreated and ferrocyanide treated date syrup were used. However, acceptable yields, in excess of 60% were obtained when the date syrup was deionised using an ion exchange column at 80°C.

Chromatic numbers of subgraphs

Given an arbitrary graph, wh~t can we say about the setl of all chromatic numbers of its subgraphs ? In particular, for e~rdinals m ~ n, does every graph of chromatic number m have a subgraph of chromatic number n? For n ~ ~t 0 the affirmative answer follows from the theorem of DE BI~UIJ~ and ERD6S [1], SO the simplest nontrivial question is whether every graph of chromatic number ~2 has a subgraph of chromatic number Nr I have no positive results; the purpose of this note is only to state the probleml in the form of 2 dubious conjectures, and to prove that the stronger conjecture implies a weak form of the GCH. If % is a set, [S] 2 = {X c~ S " [X l = 2}. We regard a graph as a system G = (V, E) consisting of a set V of vertices and a set E ~c [ V] ~ of edges. A coloring of G is a function f defined on V such thatf(x) :~f(y) whenever {x, y} # E. G is m-colorable if there is a coloring f such that If(V) l ~ m. The chromatic number of G, ehr(G), is the least m such that G is m-eolorable. A graph G" ---- (V', E') is a vertex subgraph of G if V' ~ V and E' = E N [V'~]; an edge subgraph if V' ~ V and E' c E. ConJEcturE 1. For m ~ n, every graph of chromatic number m has a vertex subgraph of chromatic number n.

Rotation restreinte de bis β dicetones I. Etude stereodynamique par R.M.N. dans la serie des dicoumarols

Rotation restreinte de bis β dicetones I. Etude stereodynamique par R.M.N. dans la serie des dicoumarols

Date syrup

Date syrup