Table of Contents
Medina, A.L. and J.N. BeMiller. 1993. Marigold flower meal as a source of an
emulsifying gum. p. 389-393. In: J. Janick and J.E. Simon (eds.), New crops.
Wiley, New York.
Marigold Flower Meal as a Source of an Emulsifying Gum
Ana L. Medina and James N. BeMiller
- Marigold Flower Polysaccharide (MFP)
- Preparation of MFP
- Sulfation (Medina Fuentes 1991)
- Emulsion Stability
- Fig. 1
Marigold (Tagetes erecta L., Asteraceae) is not only grown as an
ornamental, cut flower, and landscape plant, but also as a source of pigment
for poultry feed. The pigment is added to intensify the yellow color of egg
yolks and broiler skin. It is composed of esters of xanthophyll (lutein).
Finely ground blossom meal, often enriched with an extract, or the extract
itself, usually saponified for better absorption, is added to the feed.
Marigolds are grown for this purpose in various locations in the western
hemisphere, primarily in Mexico and Peru, by and for various companies who
produce feed additives.
One interest of the Whistler Center for Carbohydrate Research is to search for
ways to meet the need for an alternative to gum arabic, the supply of which has
been variable and uncertain. Unique properties of gum arabic are its ability
to emulsify and its ability to form high-solids, low-viscosity solutions. The
marigold flower meal that remains after removal of the xanthophyll esters by
extraction was chosen as a potential source of such a gum because it was
believed to contain a polysaccharide component that had the ability to protect
hydrophobic substances from oxidation. To remove pigment, blossoms, either
fresh or after having been stored in silos, are pressed to remove water. The
resulting cake is dried, pelletized, and extracted with hexane. The remaining
meal was used as a source of MFP in this work (Fig. 1).
Field production of marigolds is well established, especially for the Americas,
and has been studied elsewhere, particularly in South Asia (C.G. Fohner pers.
commun.). Marigolds are sown directly into a finely prepared seed bed. The
crop requires supplemental irrigation. Both overhead and furrow irrigation
should be available. The soil surface must be kept moist for uniform
germination and emergence; irrigation by sprinkler is advised to enhance
seedling establishment and minimize soil crusting. After the stand is
established, water is best applied by furrow irrigation.
Marigolds are usually grown in double rows on 75- or 100-cm beds. The crop is
sown as early as possible, for an early start promotes flowering. Final stands
in the row should be 15 to 25 cm. Under optimal germination rates, the seeding
level should be 0.37 kg/ha.
Phosphorus is required to promote flowering. Nitrogen should be applied two or
three times during the growing season. The effects of nutrients, growth
regulators, planting time, and plant density on plant growth, flower yield and
quality, and seed yield have been reported elsewhere (Parmar and Singh 1983;
Arora and Khanna 1986; Gowda and Jayanthi 1986; Ravindran et al. 1986; Shedeed
et al. 1986; Anuradha et al. 1988a, 1988b, 1990; Yadav and Bose 1988;
Arulmozhiyan and Pappaiah 1989; Girwani et al. 1990; Tolman et al. 1990).
Marigold is often intercropped with other plants. Rotation with marigolds
reduces diseases of other crops (Medhane et al. 1985; Ijani and Mmbaga 1988;
Perwez et al. 1988; Abid and Maqbool 1990), and reduces nematode populations
(Prasad and Haque 1982; Baghel and Gupta 1986; Reddy et al. 1986; Alam et al.
1988). No pesticides are registered in the United States for use on marigolds
grown for xanthophyll production, so proper site selection to minimize pest
problems is important. Marigolds are susceptible to root diseases, but risk
can be minimized by not planting marigolds in fields previously planted to
peppers and by avoiding fields that are prone to standing water. Mites can be
a severe problem on marigolds, but miticides are not registered for use on
marigolds grown for xanthophyll production or feed use.
Cultivation to control weeds is advised until the crop canopy