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Percorrer por autor "Filipe, Ana"

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  • Evaluation of biometric characteristics of hazelnuts
    Publication . Correia, Paula; Rodrigues, Catarina; Filipe, Ana; Guiné, Raquel
    The objective of this work was to develop a biometric record for application to hazelnuts in order to complement their morphological and physical characterisation as well as evaluate differences between varieties. The development of a standard biometric record was done, with several parameters for the whole fruit (nut) and the core (kernel) such as width, height and thickness. Based on these measurements, the shape ratio, the compression ratio and the volume were calculated. The width and height of the hilum and the ratio between them were also determined. It was further registered the number of hollow fruits and the calibre of each sample. The record was applied to 50 fruits, in two varieties (Grada de Viseu and Longa de Espanha), from the same orchard located in Penela da Beira region, Portugal. The fruits presented significant differences in height, mainly for the fruits with shell, with Longa de Espanha presenting the highest value. The shape and compression ratios were also very different, with Grada de Viseu presenting the highest scores for fruits with shell (0.99 ±0.06 and 0.94±0.18) and for the core (1.22±0.04 and 1.15±0.19). From the application of the biometric record it was possible to determine the nut and the core weight, and for these varieties the weight of the nut was approximately double of that of the kernel. The proposed biometric record holds the potential to be applied in quality control processes. These results could be useful in hazelnut varieties’ evaluation and choice for growers, breeders, and food industry.
    2019Documento de conferência Acesso aberto Ver mais
  • Hazelnut Storage at Controlled Conditions with Different Packaging Materials
    Publication . Correia, Paula; Filipe, Ana; Ramalhosa, Elsa; Guiné, Raquel
    The nutritional and organoleptic quality of hazelnuts can be greatly influenced by storage conditions. The aim of this study was to evaluate the effect of vacuum packaging and raffia bags on the physicochemical characteristics of hazelnuts, both in shelled and unshelled (kernel) fruits when stored under controlled conditions of temperature (25ºC) and relative humidity (65%), simulating the average annual conditions of a tropical country. The following properties were evaluated: moisture, water activity (aw), color and fat oxidative stability, both in the initial sample and also after 6 and 12 months of storage. After 6 months, the gradual degradation of the shelled and without shell (kernel) hazelnuts stored in the raffia bags was clear and they were completely damaged at the end of 12 months of storage. There was a decrease in the initial values of water activity and moisture content (being 0.76 and 8.1% respectively) in the first 6 months of storage. The aw varied significantly after 6 months, between 0.60 and 0.71 in the samples packed in raffia. The moisture of vacuum packed fruits decreased from 6 to 12 months, reaching values between 4.3% and 4.8%. As far as color is concerned, there were generally no significant variations in the L *, a * and b* coordinates during storage in the hazelnut shell or kernel. Fat stability decreased over the shelf life, with a marked decrease in the first 6 months for hazelnuts in raffia bags and after 6 months for vacuum packed ones, with vacuum packed hazelnuts showing higher oxidative stability. From this study it can be concluded that vacuum packaging allows the best preservation of hazelnuts, with color being the least affected property. Both packaging and length of storage influence the quality of the hazelnuts.
    2020-03Documento de conferência Acesso aberto Ver mais