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Cuban Journal of Agricultural Science

Print version ISSN 0864-0408On-line version ISSN 2079-3480

Cuban J. Agric. Sci. vol.53 no.1 Mayabeque Jan.-Mar. 2019  Epub Feb 05, 2019


Animal Science

Effect of the harvest season on the chemical characteristics of the sugar beet pulp (Beta vulgaris) granulated. Technical note

O.N. Arce1  * 

G. Alagón2 

L. Ródenas3 

E. Martínez-Paredes3 

V. J. Moya3 

J.J. Pascual3 

C. Cervera3 

1Facultad de Ciencias Agrarias y Naturales, Universidad Técnica de Oruro, Av. 6 de Octubre 5715, Cas. Postal 49, Oruro, Bolivia

2Facultad de Agronomía y Zootecnia, Universidad Nacional de San Antonio Abad del Cusco, Av. de la Cultura 733, Ap. Postal 921, Cusco, Perú

3Instituto de Ciencia y Tecnología Animal, Universidad Politécnica de Valencia, Camino de Vera 14, Valencia 46071, España


The chemical composition of granulated beet pulps, from the north and south of Spain, harvested in winter and summer, respectively, was characterized. The chemical composition and the content of fatty acids and amino acids of 12 samples of beet pulp were compared grouped according to their origin. The winter and summer pulps differed in the content of insoluble ash (P <0.05), neutral detergent fiber (P <0.05), soluble fiber in neutral detergent (P <0.01) and starch (P <0.01). The content of crude protein and amino acids was low, as well as that of fat, whose most representative fatty acids were linoleic, palmitic and oleic, and in any case showed differences between groups. The analysis of the main components showed that the fiber soluble in neutral detergent and the insoluble fibrous components (neutral detergent fiber and acid detergent fiber) explain 61.6 % of the variability in the beet pulp composition. It is concluded that beet pulp from the sugar industry in Spain is a by-product that provides high fiber content, soluble as insoluble, although it is important to typify the chemical nature of these fibrous components, given their variability according to origin.

Key words: fatty acids; amino acids; insoluble fiber; soluble fiber; beet pulp

The sugar beet (Beta vulgaris) belongs to the Quenopodiaceae family and is a species that contains a high sucrose concentration. It is commercially cultivated for the production of sugar and by-products that its extraction generates add 10 % to the value of the harvest (Habeeb et al. 2017). One of these wastes is beet pulp (BP), which is an important by-product widely used in animal feeding, especially if it is destined for ruminants and rabbits, where it can represent more than 20 or 10 % of the daily ration, respectively (Omer et al. 2013, Münnich et al. 2017 and Delgado et al. 2018). So that the BP can be used for animal feeding, the knowledge of its nutritional value is essential. Due to the characteristics of its chemical composition, BP is rich in cellulose, hemicellulose and pectin, and poor in lignin and protein (Foster et al. 2001), but the beet variety, the conditions of its cultivation and the extraction process of the sugar can modify its composition.

In Spain there are two beet producing areas, one in the north that is harvested in winter, and another in the south that is harvested in summer, in both areas are cultivated several varieties of beet and both include dry and irrigated crops . This crop occupied in the 2013/2014 campaign, 26605 ha in the north of the country, with a production of 2.135 million tons of beet harvested in winter, and 8662 hectares in the south, with 749.5 thousand tons in summer (MAPAMA 2018).

Due to there are important differences between the two production areas, which could influence on the chemical composition of the BP, the objective of this study was to characterize the chemical composition of the granulated pulps that are commercialized, from one and another area.

A total of 12 samples of granulated beet pulp, collected directly from the warehouses of the sugar producing plants were analyzed at the beginning and at the end of the beet campaign, by sampling in different points of the warehouse. The chemical analyzes were performed by the official methods of the AOAC (2016) for dry matter (DM), total ash (TA), crude protein (CP), crude protein linked to neutral detergent fiber (CPNDF), crude fat (CF) , neutral detergent fiber corrected for ash and protein (NDF), acid detergent fiber corrected by ash (ADF) and acid detergent lignin (ADL). The starch content (SCRIE) and soluble fiber in neutral detergent (SFND) were also determined by the method described by Martínez- Vallespin et al. (2011). The hemicellulose content was estimated by difference between NDF and ADF and cellulose, by difference between ADF and ADL. The insoluble ashes correspond to the insoluble waste of the total ashes treated with hydrochloric acid and nitric acid, washed with 1N hydrochloric acid and water and new calcination (van Keulen and Young 1977). Likewise, the content of fatty acids was determined by gas chromatography (O'Fallon et al.2007) and the amino acid content by HPLC high performance liquid chromatography (Liu et al. 1995).

To carry out the statistical analysis of the results, the Statgraphics Centurion software (Statgraphics 2010) was used. The effect of the origin of BP, summer or winter, in its chemical composition was analyzed by analysis of variance (ANOVA). The means comparison was made with t Student's test, at the significance level of P <0.05. In addition, an analysis of the main components involved in the composition of the BP was performed.

Table 1 shows the comparison, in terms of the chemical composition and the contents of fatty acids and amino acids of the BP produced in winter and summer.

It was observed that there were differences for the variables insoluble ash, NDF, hemicellulose, SFND and starch (P <0.05). Although the obtained results were in the range of values reported, there was high variability (variation coefficients higher than 10 %), except for DM and CP; being the variability recorded for hemicellulose (21 %), ADL (67 %) and insoluble ash (33 %) especially highlighted.

The total ash content coincided with those reported by Volek et al. (2003), with values around 7 %, while other authors report values between 4.4-13.2 % (NRC 2000 and De Blas et al. 2010). The 54 % of total ashes were insoluble in the winter BP, while in summer they represented only 34 % (P <0.05).The inclusion of other by-products in BP, such as vinasse, may be at the origin of these differences.

Although the CP was relatively low and did not differ between groups, with an average of 8.8 %, it was in the range of reported values (7.4-15.6 %) (De Blas and Carabaño 1996, DePeters et al. 2000, NRC 2000 and Habeeb et al. 2017). More than a half of CP (5.15 %) of BP was linked to cell walls. The CF content was relatively low (1.2 %), and similar between the winter and summer BP, and in the range between 0.5 % (NRC 2000) and 2 % (Volek et al. 2003).

The pulps have a high content of fibers, soluble as insoluble, highly digestible (Habeeb et al. 2017). The NDF fraction showed differences between the two periods (P <0.001), being 16 % higher in the summer BP, which seems to be associated with a higher hemicellulose content (P <0.05). On the other hand, the ADF content did not show significant differences between the samples, with an average value of 22 %, lower than that obtained by other authors, which place them between 25.7 and 27.0 % (De Blas and Carabaño 1996, Volek et al. 2003 and De Blas et al. 2010).

Table 1 Chemical composition, fatty acids and amino acids of beet pulp produced in Spain during the winter and summer seasons (mean and VC) 

Cellulose is an important fraction of the BP and the contents found in summer and winter are in the range of 13.1-27.5 %, reported by other authors (De Blas and Carabaño 1996, DePeters et al. 2000, and Pereira and González 2004).

The ADL content of the BP was similar at both seasons of the year. This was a very variable indicator. While De Blas et al. (2010) observed values close to 2 %, other studies refer variations from 2 to 6 % for samples from different sources (Pereira and González 2004), which may be related to the variety and the beet crop.

In correspondence with the differences found in the NDF content, the content in other complex carbohydrates more usable by the animals contained in the SFND fraction was higher (P <0.01) in the winter BP. On the other hand, the starch content was low in both seasons, although higher also in winter BP (P <0.01), which could be related to differences between the varieties of beet, or cultivation, or on the efficiency of the sugar extraction process between the factories, but that could also be due to the incorporation of molasses inside the BP before granulating, whose sugars (glucans) could be retained in this fraction during the analysis.

The BP contains little fat, and, therefore, the fatty acids are in proportions lower than 1 % of the dry matter, also presenting a high variability. The most representative fatty acids are linoleic, palmitic and oleic, with some differences between the collection time, in terms of palmitic acid, being its content higher in winter (P <0.05). The rest of fatty acids are at levels lower than 0.1 %.

The amino acid composition was similar between the BP of both groups. The most abundant amino acid was glutamic acid, followed by aspartic acid, leucine, lysine and valine, although all of them with very low values because the CP content of the BP was also very low. These values are in the range determined by De Blas et al. (2010) for lysine (0.54 %) and methionine (0.16 %).

In general terms, beet pulp is a by-product of high content of insoluble fibrous carbohydrates (cellulose and hemicelluloses) and carbohydrates soluble in neutral detergent, and with low lignin content, which makes it an excellent source of energy in those animals that have a good digestibility of this type of compounds (Cobos et al.1995 and Habeeb et al. 2017). In addition, the soluble fiber in neutral detergent is formed by soluble and insoluble pectins, soluble hemicelluloses (arabinoxylans and β-glucans), fructans and oligosaccharides (Martínez-Vallespín et al. 2011), which are given a very important function in the intestinal health of animals (Fishman et al. 2011), especially of monogastric animals (Carabaño et al. 2008 and Xiccato et al. 2011).

The analysis of the main components of the BP chemical composition shows that the main component consists of SFND, located on the left side of the graph and the insoluble fibrous components (NDF and ADF, on the right side, which explain 61.6 % of the variability (figure 1). On the other hand, the main component 2 shows that part of the variability could also be due to the ADF content and its lignification degree. These results highlight the importance of a detailed evaluation of the nature of the fibers contained in the BP.

Figure 1 Analysis of the main components of the chemical composition of beet pulp. 

It is concluded that beet pulp from the sugar industry in Spain, independent of the season, is a by- product that provides high fiber content, soluble as insoluble, although it is not an important source of BP, amino acids or fatty acids. However, it is necessary to characterize the chemical nature of these complex carbohydrates, since the pulps obtained in winter showed higher SFND content and lower in NDF.


Thanks to the Technical University of Oruro, to the Institute of Animal Science and Technology from the Polytechnic University of Valencia and to the Office of International Action of the Polytechnic University of Valencia for the financial support of the research study.


AOAC. 2016. Official methods of analysis of AOAC International. 20th ed., Rockville, MD: AOAC International, ISBN: 978-0-935584-87-5, Available: Available: , [Consulted: June 22, 2018]. [ Links ]

Carabaño, R., Badiola, I.J., Chamorro, S., Garcia, J. & Garcia-Ruiz, A.I. 2008. New trends in rabbit feeding: Influence of nutrition on intestinal health. Span. J. Agric. Res. 6:15-25. [ Links ]

Cobos, A., de la Hoz, L., Cambero, M.I. & Ordoñez, J.A. 1995. Sugar beet pulp as an alternative ingredient of barley in rabbit diets and its effect on rabbit meat. Meat Sci. 39:113-121. [ Links ]

De Blas, C. & Carabaño, R. 1996. A review on the energy value of sugar beet pulp for rabbits. World Rabbit Sci., 4: 33-36. [ Links ]

De Blas, C., Mateos, G.G. & García-Rebollar, P. 2010. Tablas FEDNA de composición y valor nutritivo de alimentos para la fabricación de piensos compuestos. Tercera edición FEDNA, Madrid. 423pp. [ Links ]

Delgado, R. Nicodemus, N. , Abad-Guamán, R., Sastre, J., Menoyo, D., Carabaño, R. & García, J. 2018. Effect of dietary soluble fibre and n-6/n-3 fatty acid ratio on growth performance and nitrogen and energy retention efficiency in growing rabbits. Anim. Feed Sci. Techol. 239: 44-54. [ Links ]

DePeters, E., Fadel, J., Arana, M., Ohanesian , N., Etchebarne, M., Hamilton, C., Hinders, R., Maloney, M., Old, C., Riordan, T., Perez-Monti, H. & Pareas, J. 2000. Variability in the Chemical Composition of Seventeen Selected By-Product Feedstuffs Used by the California Dairy Industry. Prof. Anim. Sci. 16: 69-99. [ Links ]

Fishman, M. L., Chau, H. K., Coffin, D.R., Yadav, M. P. & Hoychkiss, A. T. 2011. Physico-chemical characterization of cellulosic fraction from sugar beet pulp. Cellulose18:787-801 [ Links ]

Foster, B.L., Dale, B.E. & Doran-Peterson, J.B. 2001. Enzymatic hydrolysis of ammonia-treated sugar beet pulp. Appl. Biochem. Biotechnol. 91-93: 269-282. [ Links ]

Habeed, A. A. M., Gad, A. E., El-Tarabany, A. A., Mustafa, M. M. & Atta. M. A. A. 2017. Using of sugar beet pulp by-product in farm animal feeding. Int. J. scientific Res. Sci. Tech. 3(3): 107-120. ISSN: 2395-6011 [ Links ]

Liu, H.J., Chang, B.Y., Yan, H.W., Yu, F.H. & Liu, X.X. 1995. Determination of amino acids in food and feed by derivatization with 6-aminoquinolyl-Nhydroxysuccinimidyl carbamate and reverse-phase liquid chromatographic separation. J. AOAC Int. 78: 736-744. [ Links ]

MAPAMA (Ministerio de Agricultura, Alimentación y Medio Ambiente). 2018. Remolacha Azucarera. Gobierno de España. Available: Available: [Consulted: 03/05/2018] [ Links ]

Martínez-Vallespín, B., Navarrete, C., Martínez-Paredes, E., Ródenas, L., Cervera, C. y Blas E. 2011. Determinación de la Fibra Soluble en Detergente Neutro: Modificaciones del Método Original. AIDA. XIV Jornadas sobre Producción Animal, 1. Zaragoza: 291-293. [ Links ]

Münnich, M., Khiaosa-ard, R., Klevenhusen, F., Hilpold, A., Khol-Parisini, A., Zebeli, Q. 2017. A meta-analysis of feeding sugar beet pulp in dairy cows: effects on feed intake, ruminal fermentation, performance, and net food production. Anim. Feed Sci. Technol. 224: 78-89. ISSN 0377-84011 [ Links ]

NRC. 2000. Nutrient Requirements Of Beef Cattle. (7th ed.). National Academy Press, Washington D.C. USA. 232p. [ Links ]

O´Fallon, J.V., Busboom, J.R., Nelson, M.L. & Gaskins, C.T. 2007. A direct method for fatty acid methyl ester synthesis: Application to wet meat tissues, oils, and feedstuffs. J. Anim. Sci. 85: 1511-1521. [ Links ]

Omer, H.A.A., Abdel-Magid, S.S., El-Badawi, A.Y., Awadalla, I.M., Mohamed, M.I. & Zaki, M.S. 2013. Nutritional impact for the whole replacement of concentrate feed mixture by dried sugar beet pulp on growth performance and carcass characteristics of ossimi sheep. Life Sci. J., 10(4): 1987-1999. [ Links ]

Pereira, J.C. & González, J. 2004. Rumen degradability of dehydrated beet pulp and dehydrated citrus pulp. Anim. Res. 53: 99-110. [ Links ]

Statgraphics. 2010. Statgraphics centurión. Version XVI. Stat Point Technologies, Inc., Warrenton. VA. [ Links ]

Van Keulen, J. & Young, B.A. 1977. Evaluation of acid-insoluble ash as natural marker in ruminant digestibility. J. Anim. Sci . 44: 262-266. [ Links ]

Volek, Z., Skrivanova, V. & Marounek, M. 2003. Comparison of diets for growing rabbits containing potato pulp, sugar beet pulp and wheat bran: effect on performance and digestion parameter. Arch. Geflugelken, 68: 259-264. [ Links ]

Xiccato, G., Trocino, A., Majolini, D., Fragkiadakis, M. and Tazzoli, M. 2011. Effect of decreasing dietary protein level and replacing starch with soluble fibre on digestive physiology and performance of growing rabbits. Animal. 5(8):1179-1187. [ Links ]

Received: May 10, 2018; Accepted: February 05, 2019

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