Nutritional characterization of tomato fiber as a useful ingredient for food industry

Innovative Food Science and Emerging Technologies 11 (2010) 707–711

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Nutritional characterization of tomato fiber as a useful ingredient for food industry P. García Herrera, M.C. Sánchez-Mata, M. Cámara ⁎ Departamento de Nutrición y Bromatología II, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza de Ramón y Cajal s/n, Madrid 28040, Spain

a r t i c l e

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Article history: Received 14 May 2010 Accepted 26 July 2010 Editor Proof Receive Date 26 August 2010 Keywords: Tomato Dietary fiber By-products Functional ingredients

a b s t r a c t Tomato by-product consists of peels and seeds, presenting peel high fiber content. In this work, “tomato fiber” (TF) samples, obtained from tomato peels (after tomato processing) by a patented process, were characterized in terms of fiber and macronutrients (proteins, ash, total available carbohydrates and soluble sugars). From our results, TF is mainly composed by carbohydrates, with an average value of 80% of total dietary fiber (much higher than other vegetable by-products), being insoluble fiber the major component. The results obtained in this study reveal the high interest of TF as a food ingredient to be used as a valuable ingredient of new functional foods, enhancing insoluble fiber intake in the population. Industrial Relevance: The use of tomato by-product reduces costs and justifies new investments in equipment, providing a correct solution for the pollution problem connected with tomato processing. The results obtained in this study reveal the high interest of TF as a food ingredient to be used as a valuable ingredient of new functional foods, enhancing insoluble fiber intake in the population. According to the Regulation 1924/2006, the product TF characterized in this study can be considered under the denomination of “Source of Fiber” (more than 3 g/100 g), and for that reason food products containing the above mentioned fiber in quantities equal or superior to 3.9%, could also include the same declaration of nutritional properties in their labeling. © 2010 Elsevier Ltd. All rights reserved.

1. Introduction Tomato (Lycopersicon esculentum L.), is one of the most important crop in the industrialized world. Significant amounts are consumed either as fresh fruit or as processed products, most of which are obtained from the mature fruit crushed, sieved and concentrated, to reach different soluble solid contents (°Brix): tomato juice (at least 5°Brix); tomato paste (12–18°Brix) or tomato concentrate (28–32°Brix). During industrial transformation of tomato for concentrate, the yield of production can range between 95 and 98%, which means that about 4% solid tomato by-product is generated (Del Valle, Cámara, & Torija, 2006). Considering that the production of tomato for processing in Spain was 2355.5 × 103 tons of tomatoes in 2009, an estimated amount of 94,220 tons of tomato by-product was produced (MARM, 2009). Although food by-products can be used for animal feeding, they usually represent an environmental problem for the industry, and many studies have been carried out about the potential utilization of several vegetable origin by-products for their inclusion in the human diet, which could reduce industrial costs and justify new investments in equipment, providing a correct solution for the pollution problem connected with food processing (Lario et al., 2004).These new ingredients could be of great interest for food, pharmaceutical, chemical and cosmetic industries.

⁎ Corresponding author. Tel./fax: + 34 91 394 17 99. E-mail address: [email protected] (M. Cámara). 1466-8564/$ – see front matter © 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.ifset.2010.07.005

According to Del Valle, Cámara, and Torija (2005) tomato byproducts, consisting of peel and seeds, are rich in nutrients and bioactive compounds (as sugars, organic acids, pigments, fiber, proteins, oils, antioxidants and vitamins). In agreement with different authors, peels present high fiber values (41%) and significant amount of proteins (14%), being fat only 3%. This profile is inverted in the case of the seeds, in which proteins are the major component (32%) followed by total fat (27%) and fiber (18%). This information suggests that solid tomato byproduct may have a great nutritional and technological interest. Fiber is not a simple and well defined chemical compound, but a combination of chemical substances on composition and structure, such as cellulose, hemicelluloses, lignin, etc. being defined as “edible parts of plants or analogous carbohydrates that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the large intestine” (Mongeau, 2003). Fiber includes: insoluble fiber (lignin, cellulose and hemicelluloses) and soluble fiber (pectins, β-glucans, galactomanan gums, and a large range of nondigestible oligosaccharides including inulin). The interest of fiber in human nutrition appeared from Burkitt's work (Burkitt, Walker, & Painter, 1974) who studied the relationship between the inadequate fiber intake, and the progressive increase of degenerative diseases, in the developed societies. Nowadays, research show that the ingestion of suitable quantities of food fiber produces many beneficial effects on the digestive tract, such as the regulation of the intestinal function, improvement of the tolerance to glucose in diabetics, or prevention of chronic diseases as colon cancer (Mongeau, 2003; Pérez Jiménez et al., 2008). In addition, soluble fiber (mainly

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pectins) influences fat level and arteriosclerosis in humans and animals (Yamada, 1996). Diverse in vivo studies have demonstrated that an ingestion of insoluble fiber from fruits and vegetables can produce a significant decrease of the plasmatic concentration of cholesterol, which implies a decrease of the risk of suffering cardiovascular disease, colon cancer, diabetes and obesity. Also a regulatory activity of the immune system has been attributed to dietary fiber (Brett & Waldron, 1996). For all those reasons, the current fiber intake recommended by the Food and Nutrition Board (Trumbo, Schlicker, Yates, & Poos, 2002) in adults is 21– 38 g/day, depending on life stage groups. According to Martínez Alvarez et al. (2003) the current Europe consumption of fiber is 20 g/person/ day, so an increase of fiber consumption is needed, and a way to achieve that goal is by supplementing the diet with commercial fiber-rich products. Dietary fiber intake is not only desirable for its nutritional properties but also for its functional and technological properties (Thebaudin, Lefebvre, Harrington, & Bourgeois, 1997). The necessity of exploring new raw materials, with a balanced composition of fiber fractions and containing a high amount of associated bioactive compounds has been recognized. In this respect, tomato fruits are good candidates, with the advantage of its natural color which makes tomato fiber an attractive alternative for fiber enrichment of commercial food products, as pasta, snacks, candies, etc. For all these reasons, previous studies have reported the usefulness of high dietary fiber powder for the enrichment of usually consumed foods or for the production of dietary fiber tablets (Larrauri, 1999). All fiber enriched food products are now subject to regulation regarding the nutrition and health claims in their labelling. In this respect, Regulation (EC) No. 1924/2006 of the European Parliament and of the Council of 20 December 2006, states that in EU, a food product can only be declared as a source of fiber if the product contains as minimum 3 g of fiber per 100 g or, as minimum, 1.5 g of fiber per 100 kcal. Last trends in Food Science and Technology research are focused on developing Functional Foods especially of vegetable origin, with a higher added value. In this line, this paper is aimed to characterize the commercial product “tomato fiber” in terms of nutrients and fiber as a bioactive compound, to be used in food industry for fiber enrichment purposes. 2. Materials and methods 2.1. Samples Tomato fiber samples were obtained from Agrogal tomato processing industry (Mengabril, Spain), where the tomato by-product (peels and seeds) were separated and peels were grounded and dried to obtain the “tomato fiber” (TF) by a patented process, Patent no.: p200001264 (Bernalte et al., 2000). Samples of TF were taken in two different tomato seasons (2005 and 2006). In each year, 3 batches of TF were considered for analysis (all samples were analysed on triplicate). To avoid sample alteration they were stored in hermetic bags protected from light and moisture, at room temperature. 2.2. Analytical methods Moisture content was evaluated after drying in an air forced oven at a temperature 100 ± 2 °C, during 3 h (AOAC, 2005); total mineral content was quantified by a dry ashing technique at 450 °C (AOAC, 2005); total protein by Kjeldahl method (AOAC, 2005); total available carbohydrates were determined after hydrolysis of complex carbohydrates with perchloric acid, using the anthrone colorimetric method (Osborne & Voogt, 1986). The calibration curve was obtained by triplicate from a standard of glucose (Sigma-Aldrich, Inc.) in concentrations of 20 to 100 μg/ml. Soluble sugars were quantified by high-performance liquid chromatography with IR detector, after extraction in 80% ethanol (Mollá, Cámara, Díez, & Torija, 1994; Sánchez-Mata, Peñuela-Teruel,

Cámara-Hurtado, Díez-Marqués, & Torija-Isasa, 1998). Soluble sugar standards (glucose, fructose and sucrose) were provided by SigmaAldrich, Inc. and fructooligosaccharides (kestose, nystose and fructosylnystose) were provided by Megazyme, Wicklow, Ireland. Calibration curves were performed using standard solutions with good linearity and sensitivity parameters, as it is shown in Table 1. Total, soluble and insoluble fiber were determined by enzymatic–gravimetric methods (AOAC, 2005; Prosky, Asp Nils Georg Scheizer, DeVries, & Furda, 1998). 2.3. Instrumentation Analytical equipments used were: UV–visible spectrophotometer EZ210 model (Perkin Elmer, Waltham, MA,USA) working at 630 nm (Lambda Software PESSW ver.1.2), and HPLC system equipped with a PU II isocratic pumping system (Micron Analítica, SA, Spain); a Rheodyne valve, and a differential refractometer R401 detector (Jasco, Madrid, Spain). Chromatographic column was Luna 5 μ NH2 100R (250 mm×4.6 mm) (Phenomenex, Torrance, CA, USA). All chromatograms were processed using Biocrom 2000, 3.0 software (Micron Analítica, SA, Spain). Chromatographic conditions were: acetonitrile/water 80/20 as mobile phase and 0.9 ml/min as flow-rate. 2.4. Statistical analysis Statistical analysis of variance (ANOVA) was performed with Statgraphics plus 4.1 software. Multivariate ANOVA test of two factors was applied i) between TF batches of the same year and ii) the year of tomato campaign, in order to study their influence in all the parameter analysed. Also a Multiple Range Test (LSD Test, considering a significant level of 5%) was carried out, to know which values were different from others, and in this way, look for further explanation of the variability of tomato fiber. 3. Results and discussion Results of the proximate analysis of tomato fiber (TF) are shown in Table 2 and Fig. 2. All data related to TF is expressed and discussed on wet weight basis. Moisture content of TF ranged between 25.9 and 33.0 g kg− 1, lower values than other vegetable by-products as deseeded grape pomace (60.0 g kg− 1), cauliflower, artichoke, or chicory (90.0 g kg− 1) (Canett Romero, Ledesma Osuna, & Robles Sánchez, 2004; Femenia, Robertson, Waldron, & Selvendran, 1998). Low water content of TF was very stable in all the samples (no statistically significant differences between batches and years) and provides good properties for an easy preservation and microbiological stability. Considering that protein content in tomato pomace (fresh peels and seeds) reported by Del Valle et al. (2006) is 44.8 g kg− 1, protein content of TF (as dry peels with a moisture content less than 35 g kg− 1) is much higher due to the high moisture content of tomato pomace. A little variability of protein content of TF between batches (in a range between 57.9 and 71.1 g kg− 1) was found. This is probably due to the original material composition changes during the tomato season, although considering the average values for TF protein content of each campaign Table 1 Calibration parameters and sensitivity of the HPLC method, for soluble sugar and fructooligosaccharides analysis.

Glucose Fructose Sucrose Kestose Nystose Fructosilnystose

Equation

Range (μg)

r2 (%)

LD (μg)

A = 4001c − 45,622 A = 2553c − 10,243 A = 2439.8 c + 381 A = 1478 c − 3222.3 A = 1383.2 c − 2401.6 A = 1221.7c + 4861.8

34–170 33–134 47–235 26.4–132 21.2–106 45–90

99.97 99.94 99.78 99.90 99.48 99.71

30.20 12.04 0.45 13.40 10.67 11.93

LD = limit of detection, A = peak area, c = concentration (μg/ml).

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Table 2 Proximate composition of tomato fiber (wet weight basis). Batch

2005

2006

1 2 3 1 2 3

Moisture (g kg− 1)

Total available carbohydrates (g kg− 1)

Total fiber (g kg− 1)

Proteins (g kg− 1)

Ashes (g kg− 1)

Mean value

Mean value

Mean value

Mean value

Mean value

ab

31.51 31.13ab 33.04b 25.87a 34.97b 26.70a

a

b

131.06 133.76a 136.58a 96.70b 98.44b 125.28a

857.46 846.80b 770.63a 811.73ab 825.70ab 852.67b

a

58.12 71.06b 57.87a 60.91a 70.37b 60.25a

19.70ab 19.84a 21.24ab 22.41b 21.21ab 21.94ab

Results expressed as mean values (n = 3). Different letters mean statistical significant differences, p b 0.05 (between batches of each year and between the two years).

(2005 and 2006) there were not statistically significant differences. This protein content found in TF is lower than other fiber products reported by previous authors who indicated values from 122.5 to 636 g kg− 1 for deseeded grape pomace, cauliflower, artichoke, chicory processing byproducts (Canett Romero et al., 2004; Femenia et al., 1998). Total mineral content of TF was quite stable and very similar between batches and campaign. Although the average values were very close (20.2 g kg− 1 for 2005 and 21.8 g kg− 1 for 2006) significant differences were found (pb 0.05). Comparing with Del Valle et al. (2006) total mineral content in TF is lower than in tomato pomace (39.2 g kg− 1), but similar in either protein and ash contents to other fiber obtained from fruit by-products as apple, orange or peach (Grigelmo-Miguel & Martín-Belloso, 1999). The carbohydrate fraction was the major component of TF. Total available carbohydrates were a stable parameter on different batches of each campaign but with significant differences between the two years considered (2005 and 2006), ranging between 96.7 and 136.5 g kg− 1. These differences can be due to the fruit composition of each campaign influenced by climatic and growing conditions. Cauliflower, artichoke and chicory witloof by-products presented higher values (480 g kg− 1– 868 g kg− 1) and tomato pomace lower values (64.5 g kg− 1) than tomato fiber (Del Valle et al., 2006; Femenia et al., 1998). Although fructooligosaccharides (kestose, nystose and fructosylnystose ) can be present in tomato fruits in a very low concentration, as it has been reported by Hogarth, Hunter, Jacobs, Garleb, and Wolf (2000) who found 0.30 gkg− 1 of kestose, 0.20 gkg− 1 of nystose and 2.20 gkg− 1 of fructosylnystose in tomato paste, other authors (Campbell et al., 1997; Muir et al., 2009) did not detect any fructooligosaccharides in tomato juice, puree and sauce, considering a detection limit of 0.20 gkg− 1. In the TF analysed in this study, the HPLC method was optimized for fructooligosaccharides determination, but only fructose and glucose were identified and quantified (Fig. 1 and Table 3). Fructooligosaccharides were not identified in any of the TF analysed samples; according to

the limits of detection of the analytical applied method, it can be concluded that TF samples analysed contain less than 0.32, 0.26 and 0.60 gkg− 1of kestose, nystose and fructosylnystose, respectively. The variability in soluble sugar contents was higher than in other parameters, because sugar content is more influenced by factors as variety, environment or degree of fruit maturity used as materials for processing. As fructose and glucose are the predominant sugars in tomato fruits with levels of 3–30 g kg− 1 of fructose and 5–43 g kg− 1 of glucose, according to Fernandez-Ruiz (2003), and the content of soluble sugars diminishes during the process of elaboration of the tomato fiber with regard to the initial raw material being most of them extracted into the tomato juice (Del Valle et al., 2006). Fructose and glucose contents in TF were similar within the same campaign, but they presented statistically significant differences between years, as can be seen in Table 3 and Fig. 2, being the remaining amount in the TF of 2.861 g kg− 1 and 6.461 g kg− 1, respectively for 2005 and 2006 campaigns. The ratio fructose/glucose in TF is near to 1 (1.141– 1.307), as it is the case of fresh tomato fruit (Fernandez-Ruiz, 2003), so both compounds showed similar behaviour regarding their retention in TF. Sucrose was not detected in TF (limit of detect. 2.3× 10−4 g kg− 1), since it is present in very low amounts in the raw material, as reported by Fernandez-Ruiz (2003). The difference between total available carbohydrates and total content of soluble sugars would be other available carbohydrates (mainly starch), which represent 10.484 g kg− 1 and 4.220 g kg− 1, respectively in 2005 and 2006 campaigns. These mean a very different proportion between total soluble sugars/other available carbohydrates between campaigns, being 21.4/78.5 in 2005, and 60.5/39.5 in 2006. These differences could be attributed to a higher degree of maturity of the fruits used for TF elaboration. Fiber represented more than 80% of TF, being insoluble fiber content (726–798 g kg− 1) much higher than soluble fiber (44–85 g kg− 1), with no statistically significant differences between campaigns (Table 4 and Fig. 3). Comparing the TF by-product with other commercial vegetable byproducts, it can be observed that fiber content in TF (average value of 827.0 g kg− 1 of total fiber) is much higher than in cauliflower byproduct (23 g kg− 1 of total fiber in floret and 31 g kg− 1 in upper stem), artichoke by-product (32 g kg− 1 in receptacle and 36 g kg− 1 in stem) or than chicory by-product (7 g kg− 1 in leaf bud and 48 g kg− 1 in root)

Table 3 Soluble sugars content by HPLC in tomato fiber.

2005

2006

Fig. 1. HPLC profile of soluble sugars in tomato fiber (column: Luna 5 μ NH2; eluant: acetonitrile/water 80/20; 0.9 ml/min; refraction index detection).

Batch

Fructose (g kg− 1)

Glucose (g kg− 1)

Mean value

Mean value

1 2 3 1 2 3

1.340a 1.381a 1.852a 3.834b 3.459b 3.691b

1.350a 1.417a 1.242a 2.867b 2.944b 2.589b

Results expressed as mean values (n = 3). Different letters mean statistical significant differences, p b 0.05 (between batches of each year and between the two years).

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Fig. 2. Multiple range test (LSD, 95.0%) applied to the data of proximal composition and soluble sugar content of tomato fiber (different letters mean statistically significant differences).

(Femenia et al., 1998), as well as different types of grape pomace (about 544 g kg− 1 according to Canett Romero et al., 2004), which provides byproducts with levels of dietary fiber close to TF, as it is the case of grape antioxidant dietary fiber (730 g kg− 1) (Pérez Jiménez et al., 2008). Del Valle (2004) reported 803.9 g kg− 1 of insoluble fiber and 85.36 g kg− 1 of soluble fiber in tomato by-product, which are in concordance with those obtained in the present study on TF. However, the ratio between insoluble and soluble fiber in TF (near 10:1) is more similar to grains than to other fruit products (Grigelmo-Miguel & Martín-Belloso, 1999). From all the obtained results it can be concluded that the TF is mainly composed by carbohydrates, with an average value of 80% of total dietary fiber (much higher than other vegetable by-products), being insoluble fiber the major component, which might justify its use as a functional ingredient for the elaboration of food ingredients with potential health-promoting effects. Its inclusion in fiber poor products could contribute to enrich the insoluble fiber content, and thus enhance the fiber intake in the population. According to the Regulation 1924/ 2006, the product TF characterized in this study can be considered under the denomination of “Source of Fiber”, since its contents surpass 3 g/ 100 g (see Table 2). Considering the mean fiber content of TF product, a minimum addition of 3.9 g of TF per 100 g of final product will be

enough to meet the legal requirements to use the nutritional claim “Source of Fiber”. Results obtained in this study contribute to demonstrate that TF meets many of the requirements for an “ideal dietary fiber” reported by Larrauri (1999). Further research would be desirable, to assess the physiological effects of this fiber in the human body, as well as the physico-chemical effects in the food products enriched with “tomato fiber”.

Table 4 Fiber fractions in tomato fiber. Batch

2005

2006

1 2 3 1 2 3

Insoluble fiber (g kg− 1)

Soluble fiber (g kg− 1)

Mean value

Mean value

782.87ab 767.47ab 726.06a 746.11ab 740.06a 798.48b

74.59ab 79.33ab 44.58a 65.63ab 85.64b 54.19ab

Results expressed as mean values (n = 3). Different letters mean statistical significant differences, p b 0.05 (between batches of each year and between the two years).

Fig. 3. Multiple range test (LSD, 95.0%) applied to the data of fiber fractions of tomato fiber (different letters mean statistically significant differences).

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Acknowledgment This work has been funded by the research project UCM-PR1/06144423. References AOAC (2005). In W. Horwitz, & G. W. Latimer (Eds.), Official methods of analysis of AOAC International (pp. 2200)., 18th ed. Gaithersburg: AOAC. Bernalte, M.J., Castro Gómez, F.J., Gervasini Rodriguez, C., Hernández Méndez, M.T., Lozano Ruiz, M. & Montero de Espinosa Tena, V. (2000). New product based on fiber of tomato. Department of Biology and Production of the Vegetables. University and Extremadura. Patent p200001264. Registred Name Dates 19/05/2000. Brett, C., & Waldron, K. (1996). Physiology and biochemistry of plant cell walls, 2a ed. London: Chapman & Hall. Burkitt, D. P., Walker, A. R. P., & Painter, N. S. (1974). Dietary fibre and disease. JAMA, 229, 1068−1074. Campbell, J. M., Bauer, L. L., Fahey, G. C., Hogart, A. J. C. L., Wolf, B. W., & Hunter, D. E. (1997). Selected fructooligosaccharide (1-kestose, nystose, and 1F-b-fructofuranosylnystose) composition of foods and feeds. Journal of Agricultural and Food Chemistry, 45, 3076−3082. Canett Romero, R., Ledesma Osuna, A. I., & Robles Sánchez, R. M. (2004). Caracterización de galletas elaboradas con cascarilla de orujo de uva. ALAN, 54(1), 93−99. Del Valle, M. (2004). Utilidad del subproducto obtenido en la elaboración de derivados de tomate. Doctoral thesis, Universidad Complutense de Madrid, Spain. Del Valle, M., Cámara, M. M., & Torija, M. E. (2005). Aprovechamiento de residuos vegetales: subproducto de tomate. Alimentación, Equipos y Tecnología, 201, 87−93. Del Valle, M., Cámara, M. M., & Torija, M. E. (2006). Chemical characterization of tomato pomace. Journal of the Science of Food and Agriculture, 86, 1232−1236. Femenia, A., Robertson, J. A., Waldron, K. W., & Selvendran, R. R. (1998). Cauliflower (Brassica oleracea L), globe artichoke (Cinara scolymus) and chicory witloof (Cichorium intybus) processing by-products as sources of dietary fibre. Journal of the Science of Food and Agricultural, 77, 511−518. Fernandez-Ruiz, V. (2003). Selección de índices de calidad para la mejora de tomate. Doctoral thesis. Universidad Complutense de Madrid, Spain. Grigelmo-Miguel, N., & Martín-Belloso, O. (1999). Comparison of dietary fiber from byproducts of processing fruits and greens and from cereals. Lebensmittel-Wissenschaft und Technologie, 32, 503−508. Hogarth, A. J. C. L., Hunter, D. E., Jacobs, W. A., Garleb, K. A., & Wolf, B. W. (2000). Ion chromatographic determination of three fructooligosaccharide oligomers in

711

prepared and preserved foods. Journal of Agricultural and Food Chemistry, 48, 5326−5330. Lario, Y., Sendra, E., García-Pérez, J., Fuentes, C., Sayas-Barberá, E., Fernández-López, J., et al. (2004). Preparation of high dietary fiber powder from lemon juice by-products. Innovative Food Science & Emerging Technologies, 5(1), 113−117. Larrauri, J. A. (1999). New approaches in the preparation of high dietary fibre powders from fruit by-products. Trends in Food Science and Technology, 10, 3−8. MARM (2009). Avances de producciones y superficies agrícolas. Cultivos industriales. Boletín Mensual de Estadística. Madrid: MARM (http://www.mapa.es/es/estadistica/ pags/superficie/superficie.htm (last access 29 June 2010)). Martínez Alvarez, J. R., de Arpe Muñoz, C., Urrialde de Andrés, R., Fontecha, J., Murcia Tomás, M. A., Gómez Candela, C., et al. (2003). Nuevos alimentos para nuevas necesidades. Nutrición y Salud (pp. 188). Madrid: Consejería de Sanidad. Mollá, E., Cámara, M. M., Díez, C., & Torija, M. E. (1994, Jul-Agost). Estudio de la determinación de azúcares en frutas y derivados. Alimentaria, 87−93. Mongeau, R. (2003). Dietary fibre. In R. Macrae, R. K. Robinson, & M. J. Sadler (Eds.), Encyclopaedia of food science and nutrition (pp. 1362−1387). New York: Academic Press. Muir, J. G., Rose, R., Rosella, O., Liels, K., Barret, J. S., Sheperd, S. J., et al. (2009). Measurement of short-chain carbohydrates in common Australian vegetables and fruits by high-performance liquid chromatography (HPLC). Journal of Agricultural and Food Chemistry, 57, 554−565. Osborne, D. R., & Voogt, P. (1986). Análisis de los nutrientes de los alimentos (pp. 258). Zaragoza: Acribia. Pérez Jiménez, J., Serrano, J., Tabernero, M., Arranz, S., Díaz-Rubio, M. E., García-Diz, L., et al. (2008). Effects of grape antioxidant dietary fiber in cardiovascular disease risk factors. Nutrition, 24(7–8), 646−653. Prosky, L., Asp Nils Georg Scheizer, F. T., DeVries, W. J., & Furda, I. (1998). Determination of insoluble, soluble and total dietary fiber in food products: Interlaboratory study. Journal Association Official Analitical Chemistry, 71, 1017−1023. Sánchez-Mata, M. C., Peñuela-Teruel, M. J., Cámara-Hurtado, M., Díez-Marqués, C., & Torija-Isasa, M. E. (1998). Determination of mono-, di, and oligosaccharides in legumes by High-Performance Liquid Chromatography, using an amino-bonded silica column. Journal of Agricultural and Food Chemistry, 48, 3648−3652. Thebaudin, J. Y., Lefebvre, A. C., Harrington, M., & Bourgeois, C. M. (1997). Dietary fibers: Nutritional and technological interest. Trends in Food Science and Technology, 8, 41−48. Trumbo, P., Schlicker, S., Yates, A. A., & Poos, M. (2002). Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein and amino acids. Journal of the American Dietetic Association, 102, 1621−1630. Yamada, H. (1996). Contributions of pectins on health care. Pectins and pectinases. Progress in Biotechnology, 14, 173−190.