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- Effect of the temperature in the honey qualityPublication . Pascoal, Ananias; Lopes, Sara; Estevinho, Leticia M.; Carvalho, MarietaHoney is the natural sweet substance produced by Apis mellifera bees from the nectar of plants, secretions of living parts of plants, or excretions of plant-sucking insects on the living parts of plants, which the bees collect, transform by combining with specific substances of their own, deposit, dehydrate, store and leave in the honeycomb to ripen and mature (Decreto-Lei nº214/2003). This product can suffer alterations if the conditions of conservation and storage are not appropriate. The objective of this work was to evaluate the effect of the temperature in the physical-chemical and microbiological parameters of monofloral honeys stored for 4 months. The evaluated physical-chemical parameters were: moisture, pH, free acidity, electrical conductivity, ashes, reducer’s sugars, apparent sucrose, hydroxymethylfurfural (HMF), diastase activity and color. Relatively to the moisture none of the samples exceeded the legislated limits. The maximum value obtained for the pH were 4.92 for the heather honey maintained to room temperature and the minimum were 3.77 for the rosemary honey in the same storage conditions. Free acidity decreased in all samples, and all storage conditions. Relatively to electrical conductivity and ash, it was found that, for rosemary and cherry honeys, independently of storage conditions, the values obtained were within legal limits. Regarding to heather and chestnut honeys, the values obtained for the mentioned above parameters exceeded the stipulated by law. In all of the analyzed samples an increase of HMF was verified along the time, being this more accentuated to 45ºC. In this case, the obtained values exceeded broadly allowed it by law. Relatively to the reducer’s sugars and the sucrose it was verified, in most of the samples a progressive decrease during storage, however, in all cases, the obtained values located inside of the legislated. In most of the samples, the diastase activity decreased over the time. The storage caused a darkening of the honey, especially for the chestnut honey, stored to 45ºC. Relatively to the microbiological analysis, the aerobics mesophylics were found in some of the analyzed samples; however they never exceeded the limits stipulated by law. The moulds and yeasts just were present in the chestnut tree honey stored in the freezer. The indicators of sanitary quality and the toxigenic species were absent in all of the samples in study.
- Evaluation of the sensory quality of monofloral honeyPublication . Estevinho, Leticia M.; Lopes, Sara; Pascoal, Ananias; Carvalho, MarietaHoney is an alimentary product much appreciated due to his aroma, flavor and nutritional characteristics. The sensorial analysis is important in the evaluation of the quality and authenticity of monofloral honeys. It considers attributes as color, aroma, consistence and flavor, which are interlinked and depend on the volatile compounds related with the fragrance of the flowers where the nectar was collected. The aroma and the flavor are also related directly with honeys’ color. The objective of this work was to evaluate the pollinic profile and the sensorial characteristics of four honeys from biological mode of production. The pollen analysis indicated that all of the analyzed honeys were monofloral,presenting as dominant pollen Lavandula sp. (45.83%), Erica sp. (49.69%), Prunus sp. (61.91%) and Castanea sp. (69.01%). The results obtained in the sensorial analysis performed by the consumer’s panel were treated by the Generalized Procrustes method. It was verified that the attributes that the consumers managed to evaluate more easily and whose contribution for the global appreciation was more accentuated were the color, the flavor and the consistence. The cherry tree honey presented higher values in the scale of preferences in terms of global appreciation, color, flavor, consistence and intermediate values regarding the aroma. Concerning the heather honey, aroma was the most valued attribute. Honeys from chestnut and rosemary were the ones that received lowest punctuation.
- Avaliação da qualidade sensorial da méis monofloraisPublication . Lopes, Sara; Estevinho, Leticia M.; Carvalho, MarietaO mel é um produto alimentar muito apreciado devido ao seu aroma, sabor e qualidade nutricional. A análise sensorial é importante na avaliação da qualidade e identificação de méis monoflorais. Considera atributos como cor, aroma, consistência e sabor. Estes estão interligados e dependem de substâncias voláteis relacionadas com a fragrância das flores onde o néctar foi recolhido. O aroma e o sabor estão também relacionados diretamente com a cor do mel. Este trabalho teve como objectivo avaliar o perfil polínico e sensorial de quatro méis de produção biológica. A análise polínica indicou que todos os méis analisados eram monoflorais, pois apresentaram como pólen dominante Lavandula sp. (45,83%), Érica sp. (49,69 %), Prunus sp. (61,91 %) e Castanea sp. (69,01%). Os resultados obtidos na análise sensorial efectuada por um painel de consumidores, foram tratados pelo método Procrustes Generalizado. Constatou-se que os atributos que os consumidores conseguiram avaliar mais facilmente e cuja contribuição para a apreciação global foi mais acentuada foram a cor, o sabor e a consistência. O mel de cerejeira apresentou valores elevados na escala de preferências no que diz respeito à apreciação global, cor, sabor e consistência e, valores intermédios quanto ao aroma. No mel de urze o aroma foi o atributo mais valorizado. Os méis de rosmaninho e castanheiro foram aqueles a que os consumidores atribuíram a pontuação mais baixa.
- Evaluation of the sensory quality of monofloral honeyPublication . Estevinho, Leticia M.; Lopes, Sara; Pascoal, Ananias; Carvalho, MarietaHoney is an alimentary product much appreciated due to his aroma, flavor and nutritional characteristics. The sensorial analysis is important in the evaluation of the quality and authenticity of monofloral honeys. It considers attributes as color, aroma, consistence and flavor, which are interlinked and depend on the volatile compounds related with the fragrance of the flowers where the nectar was collected. The aroma and the flavor are also related directly with honeys’ color. The objective of this work was to evaluate the pollinic profile and the sensorial characteristics of four honeys from biological mode of production. The pollen analysis indicated that all of the analyzed honeys were monofloral,presenting as dominant pollen Lavandula sp. (45.83%), Erica sp. (49.69%), Prunus sp. (61.91%) and Castanea sp. (69.01%). The results obtained in the sensorial analysis performed by the consumer’s panel were treated by the Generalized Procrustes method. It was verified that the attributes that the consumers managed to evaluate more easily and whose contribution for the global appreciation was more accentuated were the color, the flavor and the consistence. The cherry tree honey presented higher values in the scale of preferences in terms of global appreciation, color, flavor, consistence and intermediate values regarding the aroma. Concerning the heather honey, aroma was the most valued attribute. Honeys from chestnut and rosemary were the ones that received lowest punctuation.
- Effect of the temperature in the honey qualityPublication . Pascoal, Ananias; Lopes, Sara; Estevinho, Leticia M.; Carvalho, MarietaHoney is the natural sweet substance produced by Apis mellifera bees from the nectar of plants, secretions of living parts of plants, or excretions of plant-sucking insects on the living parts of plants, which the bees collect, transform by combining with specific substances of their own, deposit, dehydrate, store and leave in the honeycomb to ripen and mature (Decreto-Lei nº214/2003). This product can suffer alterations if the conditions of conservation and storage are not appropriate. The objective of this work was to evaluate the effect of the temperature in the physical-chemical and microbiological parameters of monofloral honeys stored for 4 months. The evaluated physical-chemical parameters were: moisture, pH, free acidity, electrical conductivity, ashes, reducer’s sugars, apparent sucrose, hydroxymethylfurfural (HMF), diastase activity and color. Relatively to the moisture none of the samples exceeded the legislated limits. The maximum value obtained for the pH were 4.92 for the heather honey maintained to room temperature and the minimum were 3.77 for the rosemary honey in the same storage conditions. Free acidity decreased in all samples, and all storage conditions. Relatively to electrical conductivity and ash, it was found that, for rosemary and cherry honeys, independently of storage conditions, the values obtained were within legal limits. Regarding to heather and chestnut honeys, the values obtained for the mentioned above parameters exceeded the stipulated by law. In all of the analyzed samples an increase of HMF was verified along the time, being this more accentuated to 45ºC. In this case, the obtained values exceeded broadly allowed it by law. Relatively to the reducer’s sugars and the sucrose it was verified, in most of the samples a progressive decrease during storage, however, in all cases, the obtained values located inside of the legislated. In most of the samples, the diastase activity decreased over the time. The storage caused a darkening of the honey, especially for the chestnut honey, stored to 45ºC. Relatively to the microbiological analysis, the aerobics mesophylics were found in some of the analyzed samples; however they never exceeded the limits stipulated by law. The moulds and yeasts just were present in the chestnut tree honey stored in the freezer. The indicators of sanitary quality and the toxigenic species were absent in all of the samples in study.