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Livia PERSANO ODDOa*, Roberto PIROb with the collaboration of: Etienne BRUNEAU, Christine GUYOT-DECLERCK (Belgium); Tzeko IVANOV (Bulgaria); Ji ina PISKULOVA (Czech Republic); Christian FLAMINI, Joel LHERITIER, Monique MORLOT (France); Harald RUSSMANN, Werner VON DER OHE, Katharine Von der OHE (Germany); Panagiota GOTSIOU, Sophia KARABOURNIOTI, Panagiotis KEFALAS, Maria PASSALOGLOU-KATRALI, Andreas THRASYVOULOU, Angeliki TSIGOURI (Greece); Gian Luigi MARCAZZAN, Maria Lucia PIANA, Maria Gioia PIAZZA, Anna Gloria SABATINI (Italy); Jacob KERKVLIET (Netherlands); Joana GODINHO (Portugal); Antonio BENTABOL, Alberto ORTIZ VALBUENA (Spain), Stefan BOGDANOV, Kaspar RUOFF (Switzerland)

The invertase activity was determined for 499 honeys (27 multifloral and 472 unifloral from Arbutus, Carduus, Castanea, Citrus, Erica, Eucalyptus, Hedysarum, Helianthus, Rhododendron, Robinia, Rosmarinus, Taraxacum, Thymus, Tilia, fir honeydew and honeydew produced by Met- calfa pruinosa), in order to determine its variability and establish the range characteristic for each honey type. The results show that invertase activity varies considerably in the different honey types (from less than 0.5 to more than 30 IN). Robinia, Arbutus, Citrus, Erica and Rosmarinus have the lowest values (usually less than 10) and the two honeydew honeys the highest (more than 18). The diastase content of the samples was also measured, to compare the content of the two enzymes, and a certain correlation was observed (r = 0.835, P < 0.001). The IN/DN ratio ranges from less than 0.1 to more than 2. The possible role of invertase and IN/DN ratio in honey quality evaluation is discussed. © Inra/DIB/AGIB/Elsevier, Paris

N,N-Dialkyl-O-trialkylsilyl homoallylic hydroxylamines reacted with iodine, N-iodosuccinimide, or iodine chloride to give 3,5-disubstituted isoxazolidines in good yield. The relative configuration that was generated at C3 and C5 was controlled by the nature of the nitrogen substituent of the parent hydroxylamine: the presence of a primary alkyl group favored the formation of a cis-isoxazolidine, whereas the presence of a tert-butyl group favored the formation of a trans-isoxazolidine. The effects that the N- and O-substituents and the nature of the iodinating agent exerted on the stereoselectivity of the cyclization were examined. The synthesis of enantiomerically pure isoxazolidines from hydroxylamines carrying a chiral N-mannofuranosyl group is described

N,N-Dialkyl-O-trialkylsilyl homoallylic hydroxylamines reacted with iodine, N-iodosuccinimide, or iodine chloride to give 3,5-disubstituted isoxazolidines in good yield. The relative configuration that was generated at C3 and C5 was controlled by the nature of the nitrogen substituent of the parent hydroxylamine: the presence of a primary alkyl group favored the formation of a cis-isoxazolidine, whereas the presence of a tert-butyl group favored the formation of a trans-isoxazolidine. The effects that the N- and O-substituents and the nature of the iodinating agent exerted on the stereoselectivity of the cyclization were examined. The synthesis of enantiomerically pure isoxazolidines from hydroxylamines carrying a chiral N-mannofuranosyl group is described

A summarising table was compiled for each of the 15 important European honey types. All data reported in the tables are generally the same as found in the original works. In some cases the original measure units were transformed to the official ones (Bogdanov et al., 1997), so that they can be compared to the data of the descriptive sheets (e.g. electrical conductivity in mS/cm, invertase in U/kg, etc.). The complete references quoted in the review are listed in the reference list. The distribution of the studies per country is reported in Table I.

Une etude approfondie a ete effectuee sur 14 types de miel unifloral sur la base des proprietes organoleptiques, microscopiques (analyse melissopalynologique qualitative et quantitative) et physico-chimiques (couleur, humidite, cendres, HMF, diastase, pH, acidite totale, conductibilite electrique, rotation specifique et sucres). Les miels analyses proviennent des origines botaniques suivantes : Arbutus unedo L, Castanea sativa Mill, Citrus spp, Erica arbo-rea L, Eucalyptus camaldulensis Dehnh, Hedysarum coronarium L, Helianthus annuus L, Rhododendron spp, Robinia pseudoacacia L, Taraxacum officinale Web, Thymus capitatus Hofmgg et LK, Tilia spp, miel de miellat de sapin et miel de miellat produit par Metcalfa pruinosa. La description des caracteristiques organoleptiques (tableau 1) fournit des renseignements essentiellement orientatifs, a cause de la difficulte a traduire en paroles les perceptions sensorielles. Ce type d'analyse est etroitement lie a l'experience du degustateur. Les analyses melissopalynologiques (tableau 1) montrent que les miels de Robinia, Citrus, Tilia, Rhododendron, Arbutus and Thymus sont sous-representes ; ceux de Castanea et Eucalyptus sur-representes; Erica et Hedysarum appartiennent a la classe normale ; Taraxacum, Helianthus et les miels de miellat ont un comportement variable. Les proprietes physico-chimiques (tableaux II, III) des differents miels unifloraux sont les suivantes : Robinia : couleur claire, valeurs basses de conductibilite electrique, cendres, diastase, glucose et rapport glucose/eau (G/W) ; valeurs elevees de fructose et du rapport fructose/glucose (F/G). Hedysarum : couleur claire, valeurs basses de conductibilite electrique, cendres, pH ; valeurs elevees d'acidite. Rhododendron: couleur claire, valeurs basses de conductibilite electrique, cendres et rotation specifique. Citrus : couleur claire, valeurs basses de conductibilite electrique, cendres et diastase. Castanea : couleur foncee, valeurs elevees de pH, cendres, conductibilite, fructose et rapport F/G. Miel de miellat de sapin : couleur foncee, valeurs elevees de pH, cendres, conductibilite, di- et trisaccharides (melezitose) ; valeurs basses de monosaccharides, valeurs positives de rotation specifique. Miel de miellat produit par Metcalfa pruinosa : couleur foncee, valeurs elevees de pH, cendres, conductibilite, acidite, diastase, di- et trisaccharides (maltotriose), valeurs basses de monosaccharides, valeurs positives de rotation specifique. Helianthus : couleur jaune vive, valeurs elevees de monosaccharides (glucose) et du rapport G/W, valeurs basses du rapport F/G. Taraxacum : valeurs elevees de monosaccharides (glucose) et du rapport G/W, valeurs basses de diastase, acidite et du rapport F/G. Erica : couleur foncee avec des nuances orange, valeurs elevees d'acidite, eau, HMF, cendres et conductibilite, valeurs basses de diastase. Arbutus : valeurs elevees d'acidite, eau, cendres et conductibilite, valeurs basses de diastase. Thymus : valeurs elevees d'acidite et diastase, valeurs fortement negatives de rotation specifique. Eucalyptus et Tilia ont un comportement moyen par rapport a tous les parametres examines et sont donc moins facilement identifiables. Par consequent l'examen organoleptique est particulierement important pour ces miels.