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Cereal grains contain various amounts of non-starch polysaccharides (NSP), which are composed predominantly of arabinoxylans, b-glucans and cellulose. The detrimental effect of soluble NSP is mainly associated with the viscous nature of these polysaccharides and their physiological effects on the digestive medium. Our study had in view to investigate the influence of some extraction conditions on the viscosity of wheat and barley aqueous extracts. Water extract viscosities (WEV) appeared to be related to the particle size, the extraction time and temperature, and to the time elapsed after isolation of the extract. The experiments revealed as optimum conditions for obtaining the soluble NSP extract from wheat and barley and for WEV determination: granulation of 0.5 mm size, extraction temperature 40°C, extraction time 60 min, and viscosity measurements immediately after extract isolation. Keywords IntroductionPolysaccharides are widespread biopolymers, which quantitatively represent the most important group of nutrients in botanical feed. Carbohydrates constitute a diverse nutrient category ranging from sugars easily digested by the monogastric animals in the small intestine to dietary fibre fermented by microbes in the large intestine [1].Dietary fibre (DF) is now defined as food material, particularly plant material, that is not hydrolysed by enzymes secreted by the human digestive tract but that may be digested by microflora in the gut.The types of plant material that are included within the definitions of DF may be divided into two forms, based on their water solubility.• Insoluble dietary fibre (IDF) which includes celluloses, some hemicelluloses and lignin; • Soluble dietary fibre (SDF) which includes b-glucans, pectins, gums, mucilages and some hemicelluloses.The IDF and SDF compounds, apart from lignin, are known collectively as nonstarch polysaccharides (NSP), which was one of the earlier definitions of DF.In animal nutrition, as ''non-starch-polysaccharides'' are summarized polysaccharides, which cannot be degraded by endogenous enzymes and therefore reach the colon almost indigested. Individual NSP groups have different chemical and physical characteristics that result in various effects on physiology of intestine and on organism in general.Non-starch polysaccharides are principally non-a-glucan polysaccharides of the plant cell wall. They are a heterogeneous group of polysaccharides with varying degrees of water solubility, size, and structure.Non-starch polysaccharides, according to Ebihara and Kiriyama [2], and Englyst and Hudson [3], refer to all carbohydrate fractions and types of dietary fibre, with the exception of lignin, either soluble or insoluble. Included are pectic substances, hemicelluloses, celluloses and gums (guar) and mucilages [4,5].Cellulose, hemicellulose and pectic substances are known as plant cell wall NSP since they comprised 80-90 % of the plant cell wall [5]. Resistant starch, theoretically, falls outside the NSP concept, but practically it depends on the method used...

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The main components of the milk are: proteins (casein, lactalbumin, lactoglobulin), lactose, fat and mineral salts. The lactose concentration depends on several factors among which the health condition of the cows and the acidifying of the milk. In our days the chlorine/lactose ratio is used as a parameter for appreciating the milk quality. Although milk is isotonic with blood, the two biological liquids are very different in mineral composition, in concentration, and also in the proportion of ionised and bound to proteins forms. The osmotic pressure of the milk remains constant, and therefore when the lactose content is lower, the electrolytes are rising. Mainly, the equilibration is due to the chloride, probably the NaCl. This explains the variation of the electric conductivity. There were analyzed milk samples from 16 cows in the first lactation period, twice a month, from March to May. The pH was determined with a digital pH-meter, the conductivity (σ) with the conductivity meter type OK-102/1 (Radelkis), the chloride ion was determined by the Mohr method and the lactose by refractometry (refractometer Abbé). The determinations were performed on fresh milk and after 24 hours. σ (in mS/cm) is in negative correlation with the lactose content (in g %) [1] and in positive correlation with the chloride ion (in g %), as presented in figure 1. We conclude that the electric conductivity may be used for the appreciation of milk quality. High values show in fresh milk a high chlorine/lactose ratio, which occurs in case of mastitis. This method may be used instead of the chlorine/lactose ratio, which is more difficult to determine. The electric conductivity increases also with the acidifying of the milk when from 1 molecule of lactose 4 molecules of lactic acid are formed due the lactic fermentation of lactose. The proportion of ionic dispersed salts increases too, when casein changes (by acidifying) from calciumcaseinat in free casein