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  • The effect of drying process on the pigment content and composition of table beet varieties
    115-117.
    Views:
    173

    The food industry requires natural colouring agents in increasing quantities. Beet root is highly adapted to this purpose with its red (betacyanin) and yellow (betaxanthin) pigments suitable for numerous products. The two pigments are, however, very heat-sensitive depending not only on the method of drying as well. In our experiment we tested 6 table beet varieties with vacuum drying (instrument: Eurovac KIT-150) and obtained very big differences in the suitability of varieties for drying. The less colour loss was measured in Bordó (16.84%), while Rubin and Cylindra indicated 45.15 and 47.18% loss respectively. During the drying raw material with higher colour content produced higher rate of pigment loss (r = 0.880). In our experiment we found adverse effects on colour material and dry matter content in the fresh beet root. The variety with higher solids (mainly sugar) resulted in higher pigment loss (r = -0.847) during the vacuum drying process. Furthermore, we stated that the yellow pigments (betaxanthin) were less heat sensitive during drying than the red (betacyanin) ones. For the production of beet root powder varieties of high pigment content but low water soluble solids content (sugar) are needed.

  • Effect of hydroponic and peat-free media in transplant production of Rudbeckia hirta varieties under different photoperiodic lighting and their photosynthetic parameters
    110-117
    Views:
    360

    The purpose of this research was to determine the effects of varieties, different light conditions (short day, long day, natural short day with light pollution), and different growing media (perlite, peat-free, peat-based, aeroponics system) on Rudbeckia hirta plant production under controlled conditions (greenhouse). The morphological effects of each treatment (photoperiodic lightings and media) on different Rudbeckia varieties determined at 11 weeks-old ’Napfény’, ’Toto Gold’, ’Autumn Colors’, ’Prairie Sun’ and 16 weeks-old ’Napfény’. Plantlets received 12 hours daylight did not initiate flowers, remained stage of the leaf rosette in case of all varieties. The 14 hours light treatment in the aeroponics system and the same treatment in perlite and control (natural short day with 14 hours light pollution) plantlets had developed inflorescences or flower buds. The inflorescence axis of ‘Napfény’ was appeared at 13 weeks under long-day conditions, with 1.7 (perlite) - 2.7 (aeroponics) flower buds in 16 weeks. ’Toto Gold’, ’Autumn Colors’, ’Prairie Sun’ varieties developed inflorescences at 8 weeks, 14 hours aeroponics system resulted in the most of flower buds (’Toto Gold’: 6.5, ’Autumn Colors’: 3.25,’Prairie Sun’: 4.8 flower buds) at 11 weeks. Long daylight manipulation could be minimized crop times and achieved flowering potted plants at 11 weeks. The peat-based and peat-free media effect was observed on ‘Autumn Colors’. The number of leaves of peat-free ‘Autumn Colors’ transplants (16.8-20.3) was significantly higher than peat-based media (13.5-15.5). Other morphological parameters were not affected by the media treatments.