International and national production

The Chia began to be commercialized at international level from the nineties. It is grown in Argentina, Mexico, Bolivia, Paraguay and Australia. In 2011-2012 Argentina participated with a production of 35%. While Australia, México, Bolivia and Paraguay participated with 15% and 3 000 ha each (^{Busilacchi et al., 2015}). Recently, Nicaragua and Southeast Asian countries were incorporated as producers (^{Jamboonsri et al., 2012}). The world production has grown rapidly, an example of which is Nicaragua, where chia production increased from, 5 000 quintals in 2013 to 180 000 quintals in 2014.

Table 1 shows the behavior of chia, where it is clear the growth in the area planted, as well as the behavior of price and yield per hectare.

Fuente: SIAP, 2016.

Table 1 Evolution of production of chia in México. 

Production in Mexico is concentrated in Jalisco and Puebla, and new areas with productive potential are being introduced, as shown in Table 2. In Jalisco production is concentrated in the municipalities of Acatic, Cuquío, Ixtlahuacán del Río and Jamay, while in Puebla the producing municipalities are: Atzitzihuatlán, Huaquechula, San Felipe Tepemaxalco and Tochimilco (^{SIAP, 2016}).

^{SIAP, 2016}

Table 2 Distribution chia production in México during the spring-summer of 2014.  

Morphological description

S. hispanica L. is an annual herbaceous plant, from 1 to 1.5 m in height, with branched stems of quadrangular and hollow section, with short and white pubescences; opposing leaves with serrated edges 80 to 100 mm in length and 40 to 60 mm in width, with different degrees of pubescence. The flowers are hermaphrodite, blue or white, most commonly indehiscent fruits (^{Capitani et al., 2013}) in groups of four monospermic oval clusters 1.5 to 2 mm in length and 1 to 1.2 mm in diameter; (^{Di Sapio et al., 2012}), the weight of 1 000 seeds varies between 0.94 and 1.29 g (^{Bueno et al., 2010}).

It is defined as an autogamous plant, with higher levels of cross-pollination in cultivated chia, than in wild chia, insects are responsible for cross-pollination, obtaining higher yields when there is the presence of bees in the growing area (^{Cahill, 2004}). The most widely used propagation in chia is through seed (^{Ayerza and Coates, 2006}).

Agronomic aspects

The planting of chia is from May to mid-June, to avoid frost. Seed depth is a limiting factor in establishing the crop due to low seed reserves (^{Migliavacca et al., 2014}) and because the seed is small, it requires little depth of planting to emerge successfully, just enough to cover the seed and a maximum of 10 mm (^{Rojas, 2013}). The seed requires moisture to germinate, but already sprouted and established the plants grow well with limited amounts of water because it is a plant with low water consumption and adapted to arid and semi-arid climates (^{Ayerza and Coates, 2006}). It develops adequately in sandy soils with medium texture and good drainage; do not tolerate flooded soils (^{Coates, 2011}).

It is a short-day plant sensitive to photoperiod, presenting favorable response to flowering on short days (^{Jamboonsri et al., 2012}), the growth period is affected by the latitude in which it develops, so the cycle of cultivation varies from 90 to 150 days (^{Ayerza and Coates, 2006}). The appropriate pH for the crop is 6.5 to 7.5, the crop site affects the composition of the seeds due to environmental factors such as temperature, light, soil and available nutrients (^{Ayerza and Coates, 2004}). Seeding is done in rows of 0.7 to 0.8 m of separation, with a seed density of 6 kg of seeds per hectare (^{Busilacchi et al., 2013}). The method of sowing and density influence the growth and yield of chia. The higher the density, the more biomass and therefore the seed yield increases, the more appropriate density is the greater than 40 000 ha^-1 plants (^{Yeboah et al., 2014}).

Their seeds present moderate tolerance to saline stress, but when under high salinity the percentage of germination, root length and plant size decreases, therefore it is recommended to avoid the use of chlorinated fertilizers (^{Dal’maso et al., 2013}).

Phytosanitary aspects

Chia contains chemicals (quercetin, kenferol, myricetin, chlorogenic acid and caffeic acid) that have a preventive effect against disease incidence (^{Miranda, 2012}). The cultivation is attacked by insect pests, of the order hymenoptera that attack the floral bud, defoliating beetles of the order Coleoptera, grasshoppers of the order orthopter and diopsis of the order of dipterans (^{Yeboah et al., 2014}). Other common pests are slugs (Arion ater), snails (Helix aspersa), blind hen (Phyllophaga sp.), Cutter ant (Atta cephalotes), hairy worm (Estigmene acrea) and lobsters (Spodoptera sp.).

The diseases with economic incidence are: Fusarium solani, Pallidoroseum sp., Rhizopus sp., Cladosporium sp. (^{Yeboah et al., 2014}) and leaf spot caused by Cercospora sp. (^{Miranda, 2012}).

Market

The demand for chia is increasing and is led by EE. UU. It is a crop that has a significant potential market at national and international level. In the USA UU’s production of chia products is on the rise, in 2011, 21 new chia products (fruit juices) were introduced and in 2012 that quantity increased to 100 products (^{Busilacchi et al., 2015}). The European Union countries are recently incorporating chia consumption, as a result of the authorization of their inclusion in processed foods and in the future, it is expected that Asian countries will join this demand, which would double to 40 000 t year^-1 (^{Busilacchi et al., 2015}).

The international market requires chia seed from gray to black, characteristic taste of the seed, characteristic odor of the seed; with specific physical chemical specifications of: moisture percentage of 12% maximum, microbial specifications with total count: max. 100 000 cfu g^-1, fungi: max. 1 000 cfu g^-1, yeast: max. 1 000 cfu g^-1, Sclerichia coli: <10 cfu g^-1, Staphylococcus aereus: <10 cfu g^-1, peroxide index: <0.1meq 0.2 kg^-1, Impurities: (%) 1.07, omega-3 fatty acid: 17.5% of total oil and bag packing of high density polypropylene 18*27*14*14 20 kg (^{Miranda, 2012}).

Distribution channels in the United States of America are derived from three groups of actors in the marketing chains, wholesale importers, food processing companies and retail distributors, in order to reach consumers (^{Busilacchi et al., 2015})

Propagation

The propagation of chia is carried out by the use of seed, recently researches have been carried out on in vitro culture of the parts of the plant, the stems are the best explant source for callus cultivation. The ideal culture medium is MS 2.4-D (2.25 M) as plant growth regulator and 16 h photoperiod. To maintain growth add Na + (0.54: 0.46M) (^{Marconi et al., 2013}). Sucrose added to culture media inhibits somaclonal variation, and osmotic potential, due to macro and micronutrient concentrations that directly influence embryo germination (^{Arfux et al., 2015}).

Components chia

Chia seeds are composed of nutrients, vitamins, antioxidants and fatty acids (Table 3). The quantity and quality of the components may vary by crop site, environmental conditions, nutrient availability, crop year or by type of soil (^{Ayerza and Coates, 2009}). Chia is a complete and functional food because of its antioxidant content (chlorogenic acid, caffeic acid, myricetin, quercetin and kaempferol flavonols), safe levels of heavy metals, being free of mycotoxins and not containing gluten (^{Mohd, 2012}).

^{Bueno et al. (2010)}; ^{Ixtaina et al. (2011)}; ^{Segura et al. (2014)}; ^{Ullah et al. (2015)}.

Table 3 Composition of chia seeds (100 g of edible portion).  

Chia is the vegetable source with the highest content of essential fatty acids, its oil contains physicochemical properties of interest for the food industry, considered as a potential food ingredient due to its benefits in human health because it contains 85.4% of polyunsaturated fatty acids (^{Segura et al., 2014}).

Uses of chia

Chia is consumed commercially without any processing or added as enriching of products (confectionery); in México, a refreshing drink called “chia fresca” is prepared; a mucilage is also prepared by letting the seed rest in water, to be used as dietary fiber or to add it and give thickness to jam, jelly, yogurt, mustard and tartar sauce; also has utility in cosmetology, in baking (where the gel is used as an oil substitute) to enhance its flavor and to cover the dough before baking and thus increase shelf life (^{Busilacchi et al., 2015}). It is an excellent enricher of products like formulas for babies, animal foods, nutritious bars, etc (^{Busilacchi et al., 2015}).

The mucilage or gel obtained from the soluble fiber contained in the seed, is a source of hydrocolloids with properties of water retention, emulsifier, thickener, stabilizer, and soluble in hot and cold water. (^{Muñoz et al., 2012}). The mucilage content in seeds is 3.5%. The composition of the mucilage is: moisture 9.37%, protein 29%, crude fiber 11.42%, oil 3.83%, ash 10.27% and 56.24% of nitrogen-free extract (^{Guiotto et al., 2016}).

By ingesting seeds, contact with saliva forms the gel and when ingested, the gel has favorable effects on nutrition and health because it generates a soothing effect on the digestive tract, creates a barrier for enzymes slowing the decomposition of the complex carbohydrates in sugars, there being a sensation of satiety by the increase of the volume of the hydrates and the viscosity in the intestine; which leads to a more efficient digestion, prolonging the sensation of satiety (^{Capitani et al., 2012}).

The incorporation of chia seeds in baking increases the nutritive value of the product due to the proportion of omega fatty acids and dietary fiber provided by them, without altering the quality of the bread and changing only the color of the crumb, in addition there is a change in the kinetics of amylopectin during storage, which is directly related to the increase in shelf life (^{Iglesias and Haros, 2013}). With addition, the n-3 alpha-linolenic content increases, with a higher omega-6/omega-3 ratio, and also contributes to a reduction in specific volume and lightness of bread (^{Luna et al., 2015}). The amount of water and flour or seeds without affecting the baking 2% mixed before kneading with 5 g of flour per g of water, since in these quantities the volume and the softness of the bread crumb are maintained in a positive way (^{Zettel et al., 2015}).

Whole chia seeds that are used in food products are not digested and easily used by the human body because of an extremely hard coating. But if added as flour they improve the nutritional value, texture, and functional food applications (^{Inglett et al., 2014}). Chia oil is used by artisans from the states of Chiapas, Guerrero, Michoacán and Mexico City to prepare lacquer known as maque, for the purpose of painting jicaras and guajes, this art flourished in ancient México from before the arrival of the Spanish, and which is extracted by slowly roasting and burning under the seeds of chia, to be ground later and adding hot water is kneaded until the oil begins to drain, later the oil is boiled to preserve it (^{Ayerza and Coates, 2006}).

Nutraceuticals uses

Chia seed is considered a “functional food” because it contributes to human nutrition, increases satiety index, prevents cardiovascular diseases, inflammatory and nervous disorders, and diabetes. It absorbs 27 times its water weight (^{Muñoz et al., 2012}), for its content of soluble dietary fiber, helping to counteract problems of constipation, diverticula and colon cancer (^{Alvarado, 2011}). For this, ingest 15 to 25 g of seeds soaked in water for 15 minutes for 20 days (^{Bernal et al., 2015}).

A 12-week supplement with 35 g of flour day^-1 of chia in the human diet resulted in a significant reduction in weight and waist circumference, thanks to its dietary fiber content that acts as satiety and decreases caloric intake by high viscosity of the gel formed in the gastrointestinal tract, as well as the high Omega 3 content that suppresses appetite, improving lipid oxidation and energy expenditure (^{Toscano et al., 2015}).

The continuous intake of chia for 12 weeks helps diabetics to control the glucose level after food intake (postprandial blood glucose), improving blood pressure and blood clotting (^{Vuksan et al., 2010}). Chia oil is used as a moisturizing adjuvant agent for pruritic skin, characteristic of people with kidney deficiency and diabetes, improving the epidermal barrier function of skin permeability and hydration (^{Jeong et al., 2010}).

Problems with chia

The seeds of chia have very short viability, which decreases with the passage of time, in addition to this the quality is affected by the environmental conditions of storage and time of the same, besides that the quality of the seeds will depend on the present environmental conditions in its maturation (^{Bueno et al., 2010}).

It is common to find seeds of different color in the same set of them, the predominant ones are mottled gray (86%), white and brown. Seeds of heather gray and white are the ones with the highest weight and are composed of all their own structures of the seeds, while those of brown color are of lower weight and are empty seeds, having null development of the seminal structures (^{Rovati, 2010}).

Perspectives of chia

Mexico has the optimal ecological conditions for chia production under temporary conditions, and these conditions are optimally found in low and intermediate altitude areas, which shows that the climatic conditions of the areas between 0 and 2 200 m above sea level meet the requirements (^{Jamboonsri et al., 2012}; ^{Orozco et al. 2014}), with excellent productivity in the high regions of Jalisco, Nayarit, Michoacán, Morelos, Puebla, México, Guerrero, Oaxaca and Chiapas. Soil type, precipitation and altitude are the factors that determine optimal areas for cultivation (^{Ramírez and Lozano, 2015}).