Changes in physical properties and chemical constituents of parsley herb volatile oil during storage

The present work was carried out to study the chemical composition of parsley herb [90- 100 day-old] produced in Egypt. The chemical composition and the physicochemical properties of volatile oil obtained by steam distillation of parsley were also studied. In addition, the effect of storage conditions of parsley herb volatile oil [PHVO] on its quality attributes was investigated. Twenty-two compounds were identified in this oil by using Gas liquid chromatography [GLC] and Gas liquid chromatography-mass spectrometry [GLC-MS]. The major constituents were beta-myrcene [23.75%], beta-phellandrene [19.47%] and myristicin [8.79%]. Moreover, three compounds were first identified in the parsley herb volatile oil, i.e. 5-undecen-3-yne [0.06%], cyclohexene, 1-methyl-4-[5-methy-l-methylene-4-hexehyl] [0.21%] and 2- pyridinamine, 4-methyl [0.40%]. The results revealed that the lowest changes in quality attributes of oil occurred in oil samples stored in filled up dark glass bottles or aluminum bottles kept at freezing temperature [-5°]

Retardation of honey granulation by heat treatment

Sample of clover honey were treated at 55 degree, 65 degree and 75 degree Cent. for 30 minutes to prevent or retard the development of granulation in honey. The best results were attained in the samples treated at 75 degree Cent. or 85 degree Cent., in which no granulation appeared before two weeks of storage at 5 degree Cent. The data also showed that there was a linear relation between viscosity and the granulation developed in honey during storage. The chemical analysis of honey after heat treatment indicated that the contents of moisture, protein, ash [especially Mg, Fe and Na], non reducing sugars and ascorbic acid were decreased. Raising temperature used in heat treatment regularly increases the dark substances developed in honey, hence it is preferable to treat honey at 75 degree Cent. than 85 degree Cent. Moreover, heat treatments had three different effects on the volatile aroma of honey: the first was on the highly sensitive chemical groups which completely disappeared, the second was on the sensitive groups which partially disappeared, and the third was on the insensitive groups which were unaffected by heat treatments. In general, the total aroma of honey increased by heat treatments may be due to the conversion of some non volatile substances to volatile compounds. Although the total aroma of honey increased by heat treatments, it became less acceptable due to the cooked flavor developed