Comparative evaluation of chemical composition of hulled and hull-less cereals

English. The aim of experiment was to evaluate and compare grain chemical composition (crude protein, starch, crude fat, crude fibre, crude ash and phosporus) of hulled and hull-less cereals. The four hull-less barley varieties and lines – 'Gainer' (Canada), 'KM–2084', (the Czech Republic), 'L– 302' (Latvia), 'SW–1291' (Sweden), one hulled barley variety – 'Linga' (Latvia), hull-less oat line 'L–28156' (Latvia), hulled variety 'Laima' (Latvia) and spring wheat variety 'Vinjett' (Sweden) were included in this study. Field experiments were carried out at the State Stende Cereal Breeding Institute in 2004–2006. All plots received 60 kg ha-1 nitrogen (N). On the average for all hull-less varieties, the content of crude protein ranged from 129.7–171.0 g kg-1. The hulled variety 'Linga' contained 140.7 g kg-1 crude protein. The content of crude protein for hull-less oat line was 170.9 g kg-1 and it was significantly higher than for covered oat variety (120.9 g kg-1), but spring wheat 'Vinjett' (133.3 g kg-1) took place between hulled barley and hulled oat. In 2006, hot summer temperatures increased the crude protein content in all cereal varieties. There were differences in starch content among cereals. Regarding to starch content the species were ranged in following order: wheat- hull-less barley- hulled barley- hull-less oat- hulled oat (668, 623–686, 598, 589, 454 g kgE-1, respectively). The hull-less line L–28156 showed the highest fat content – 91.7 g kgE-1. This value exceeded 1.5 to 3.8 fold the content of fat found in hulled oat, hulled and hull-less barley and spring wheat. The hull-less barley, hull-less oat and spring wheat had the lowest crude fibre content 18.3–24.3 g kg-1, 20.3 g kg-1and 28.5 g kg-1, respectively. The hulled barley and oat contained from 2 to 5 fold more crude fibre than hull-less types. Hulled varieties of barley and oat had higher crude ash content (23.0–25.2 g kg-1) than hull-less type (17.6–22.2 g kg-1). The results of grain chemical composition suggest that the hull-less varieties of barley and oats might awake interest for food and feed producers.

Latvian. Ar augstāko kopproteīna saturu izmēģinājuma gados raksturojas kailgraudu miežu līnija L–302 (vidēji 171.0 g kgE-1 ) un kailgraudu auzu līnija L–28156 (vidēji 170.9 g kgE-1). Tām seko pārējās kailgraudu miežu līnijas, plēkšņainie mieži, vasaras kvieši un plēkšņainās auzas. Starp vasaras kviešiem un kailgraudu miežiem nav konstatētas būtiskas atšķirības pēc cietes satura. Plēkšņainām auzām ir viszemākais cietes saturs un sastāda 66–77 %, salīdzinot ar citiem graudaugiem. Visaugstākais tauku saturs ir kailgraudu auzām (vidēji 91.7 g kg-1 ), būtiski pārsniedz (1.5–3.8 reizes) tauku saturu plēkšņainajās auzās, kailgraudu un plēkšņainajos miežos un vasaras kviešos. Intensīvāka tauku uzkrāšanās graudos atzīmēta 2005. gadā, kad veģetācijas periods raksturojās ar bagātīgiem nokrišņiem. Plēkšņainie mieži un auzas satur 2.1–5.8 reizes vairāk kokšķiedras salīdzinot ar kailgraudu genotipi. Plēkšņainos miežos un auzās vidēji ir par 3.0–7.7 % augstāks koppelnu saturs nekā kailos graudaugos. Plēkšņaino un kailo miežu un auzu, kā arī vasaras kviešu graudu ķīmiskā sastāva mainību ietekmē meteoroloģiskie apstākļi veģetācijas periodā.