Food Hydrocolloids 62 (2017) 158e164

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Food Hydrocolloids

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Passion fruit peel flour e Technological properties and application in food products

Emanuela Monteiro Coelho a, b, Raquel Guttierres Gomes c, Bruna A. Souza Machado d, * Roseane Santos Oliveira d, Marcos dos Santos Lima a, Luciana Cavalcanti de Azevedo^ a, , Marcelo A. Umsza Guez b a Department of Food Technology, Federal Institute of Sertao~ Pernambucano, BR 407 Km 08 Jardim Sao~ Paulo, 56314-520, Petrolina, Pernambuco, Brazil b Department of Science in Food, Federal University of Bahia, Av Ademar de Barros, s/n, Campus Ondina, 40170-115, Salvador, Bahia, Brazil c State University of Maringa, Av Colombo, 5790, Cidade Universitaria, 97020-900, Maringa, Parana, Brazil d Food Technology, Senai CIMATEC, Av. Orlando Gomes, 1845, Piata,~ 41650-010, Salvador, Bahia, Brazil article info abstract

Article history: The peel of passion fruit is rich in fiber which has properties comparable to food additives. Thus, in this Received 19 April 2016 study, the technological properties of flour obtained from yellow passion fruit peel were determined and Received in revised form compared to those of five commercial additives. Two flour samples were prepared from passion fruit 1 July 2016 shells through a modified process in order to evaluate their potential use as a stabilizing agent, emul- Accepted 24 July 2016 sifier, thickener and gelling agent. These characteristics were then compared to those of low and high Available online 25 July 2016 methoxyl pectins, xanthan gum, guar gum and carrageenan. The flour samples obtained have significant stabilizing capacity, as they were able to hinder particle settling when applied to nectars. Another Keywords: Thickener positive feature observed was the emulsifying potential, showing similar results to additives commonly fl Stabilizer used in mayonnaise, such as xanthan and guar gums. The our samples also showed good properties as a Gelling agent thickening and gelling agent in ice cream toppings and structured fruit. The results demonstrate that Emulsifier flour produced from passion fruit peel can be used to replace the commercial hydrocolloids studied since, Passiflora edulis besides being obtained through simple procedures and associated with low cost, the flour samples showed similar technical characteristics with regard to their stabilizing, emulsifying, thickening and Chemical compounds: gelling power. Carrageenan (PubChem CID 6850766) © Xanthan gum (PubChem CID 7107) 2016 Elsevier Ltd. All rights reserved. Pectins (PubChem CID 441476)

1. Introduction Fiber has some properties comparable to food additives which act as thickening or gelling agents and stabilizers of emulsions and The passion fruit vine belongs to the family Passifloraceae and foams. In addition, it is a fat mimetic. Moreover, it has swelling genus Passiflora. It is a native plant of tropical America and is capacity and can increase water retention, properties which are cultivated in regions with a tropical or subtropical climate (Kishore, essential for the preparation of creams, sweets and frozen des- Pathak, Shuklar, & Bhar, 2011). serts, among other food products (Ayala-Zavalaa et al., 2011; Passion fruit industrialization is generally aimed at juice and http://www.sciencedirect.com/science/article/pii/S096399691300 nectar production. In this process, 54,000 tons of by-products, such 0823 Martinez et al., 2012). Elleuch et al. (2011) reported that, in as seeds and peel, are generated per year in Brazil. Albedo (or pith), addition to the previously mentioned characteristics, fiber can the main peel component, is rich in fiber and pectin, and can be modify the textural properties, prevent syneresis and improve the used as an ingredient in the preparation of functional foods. shelf-life of foods such as sweets, soups and dairy and bakery Furthermore, it can be added to products that require an increase in products. viscosity (Lopez-Vargas, Fernandez-L opez, Perez- Alvarez, & Viuda- The main reason for the widespread use of hydrocolloids in Martos, 2013). foods is their ability to alter the viscosity and texture of the prod- ucts (Marcotte, Hoshahili, & Ramaswamy, 2001; Saha & Bhattacharya, 2010). Hydrocolloids, such as xanthan gum, carra- * Corresponding author. geenan, guar gum and pectin, are generally used in foods due to E-mail address: [email protected] (L.C. de Azevedo).^ http://dx.doi.org/10.1016/j.foodhyd.2016.07.027 0268-005X/© 2016 Elsevier Ltd. All rights reserved. E.M. Coelho et al. / Food Hydrocolloids 62 (2017) 158e164 159 their thickening, stabilizing, gelling and emulsifying properties, 2.3. Product preparation, technological assessment and among others (Codex Alimentarius, 2015). instrumental analysis The literature reports several studies on passion fruit peel flour carried out to investigate, for instance, pectin extraction In order to determine the technological properties of the two (Kliemann et al., 2009; Pinheiro et al., 2008; Seixas et al., 2014; flours (UF and TF), four different products were developed (nectar, Yapo & Koffi, 2006; Yapo, 2009), addition to functional bever- structured fruit, passion fruit ice cream syrup and mayonnaise). ages (Pineli et al., 2015) and the preparation of flexible films for Eight formulations were produced for each product with different food products (Nascimento, Calado, & Carvalho, 2012). However, types of additives and they were analyzed in triplicate. Five for- the application of raw flour as a hydrocolloid agent is still little mulations contained commercial additives (hydrocolloids), that is, explored. carrageenan (CAR), guar gum (GUA), xanthan gum (XAN) and low In this context, the aim of this study was to prepare food (LMP) and high (HMP) methoxyl pectins. The sixth formulation products using commercial additives and passion fruit peel flours, contained UF, the seventh contained TF and the eighth formulation in order to evaluate the technological properties of the flour sam- was the control, without hydrocolloid addition, referred to herein ples with regard to their thickening, stabilizing, emulsifying and as CTL. gelling power. 2.3.1. Flour stabilizing power when added to passion fruit nectars 2. Material and methods The passion fruit nectar was prepared with a concentration of 20% pulp and 80% distilled water. The addition of other ingredients º 2.1. Raw material was calculated on a 100% basis, with 11% soluble solids ( Brix) and 0.1% of each additive, according to the standard methods estab- Passion fruit peel was used to prepare two flour samples. The lished for nectar (Brazil, 2003, 2013). first was obtained by maceration in water for 12 h, applying an The stabilizing power of the additives was assessed applying an adapted version of the methodology described by Oliveira, adapted version of the methodology described by Babbar, Nascimento, Borges, Ribeiro, and Ruback (2002), and is referred Aggarwal, and Oberoi (2015), by calculating the percentage of to herein as treated flour (TF). The second sample, not subjected to suspension (cloud) in the nectar. The cloud volume was measured fi maceration, is referred to as untreated flour (UF). every 30 min for the rst 8 h and then every hour until stabilization. In order to obtain the flour samples, the peel was cut into strips Samples were kept under refrigeration for seven days. Calculations of approximately 1 cm. These were then dried in a dryer with forced were performed using Eq. (3): air circulation at 50 C until reaching constant weight (model h i. ¼ Meloni - PE 30, Brazil). The dried strips were grinded in an indus- %Suspension Hjb Hc 100 Hjb (3) trial blender and sieved until flour samples with particles smaller than 150 mm were obtained. where Hjb ¼ height of juice in the bottle and Hc ¼ height of cloud.

2.3.2. Emulsifying power of flours added to mayonnaise and color 2.2. Rheological analysis of hydrocolloids analysis Mayonnaise was prepared using oil, eggs and salt, plus 0.05% The rheological parameters of the hydrocolloids under study citric acid and 0.1% of each additive, according to standard methods (carrageenan e CAR (INS 407), guar gum e GUA (INS 412), xanthan established in Brazilian regulations (Brazil, 2007). The emulsifying gum e XAN (INS 415) (Sigma-Aldrich, USA) and low (LMP) and high power of each formulation was evaluated considering the texture (HMP) methoxyl pectins (INS 440) (CPKelco, USA)) and the passion profile, using a CT3 10K texturometer (Brookfield, USA) with a fruit peel flours (UF and TF) were obtained in triplicate, at 25 C, TA15/1000 tapered tip. Analysis was conducted at room tempera- using a cone and plate rheometer (Thermo Scientific, model MARS ture with 10 g samples, which were placed in porcelain capsules III). An increase in the shear stress was obtained by increasing the and analyzed in triplicate. For the evaluation, a TPA-type parameter rotation, through continuous variation of the cone angular velocity. was determined applying a load of 4 g, velocity of 2 mm/s and Shear gradients from 0 to 700 s1 were applied for 30 s, with a C60 target value of 4.0 mm. The parameters determined were hardness, cone-plate and 0.5 ml of sample. Thus, ascending and descending adhesion strength, adhesiveness, cohesiveness and gumminess. curves were obtained. The strain rate was determined using a Color analysis was also conducted using a MiniScan EZ digital computer program (RheoWin Data Manager, by Thermo) employ- colorimeter (Hunterlab, USA) and CIE Lab L*, a * and b * system, ing Eqs. (1) and (2): where L* denotes lightness and ranges from 0 (black) to 100 g ¼ u=sinq (1) (white), and a* and b* denote opposite dimensions, ranging from green () to red (þ) and from blue () to yellow (þ), respectively. T t ¼ (2) fl 2 pr3 2.3.3. Thickening power and water activity assessment of ours 3 added to passion fruit syrup Passion fruit syrup for ice cream topping was prepared with 10% where g ¼ shear rate (1/s), T ¼ shear stress (Pa), w ¼ angular speed pulp and 90% water (100% mixture) and 30% sugar, 0.05% citric acid of the cone (rpm) and P ¼ cone angle. and 0.1% of additives under study were added to the syrup. The The rheological behavior was determined using the power law mixture was concentrated at a temperature of 180 C, until reaching rheological model (K ¼ tgn) with the aid of Origin software (version 60Brix. 6.0). The thickening power was determined by viscosity analysis in a Ford viscosity cup (Omicron, Brazil) with a No. 4 orifice at 20 C. Viscosity analysis involves determining the time the sample takes 1 Departamento de Pos-graduaç ao~ em Ciencias^ em Alimentos, Universidade Federal da Bahia, Av. Ademar de Barros, s/n, Campus Ondina, CEP: 40170-115, Sal- to drain. Calculations were performed through an equation pro- vador, Bahia, Brazil. vided by the manufacturer (equation Eq. (4)), using the Centistoke 160 E.M. Coelho et al. / Food Hydrocolloids 62 (2017) 158e164

(cSt) measurement unit: 3.2. Product preparation, technological assessment and instrumental analysis V ¼ 3:85 ðDt 4; 49Þ (4) 3.2.1. Stabilizing power of flours in passion fruit nectar and color ¼ ¼ fi where V speed and Dt nal time initial time. analysis In addition, water activity (aW) was measured in triplicate The effect of the hydrocolloids on the cloud sedimentation through direct readings, using a portable water activity meter characteristics of the passion fruit nectar can be observed in Fig. 1. (Aqualab, Decagon Device, Pollman,WA). Nectar samples containing different hydrocolloids reached decan- tation equilibrium in 18 h. It should be noted that the efficiency of 2.3.4. Gelling power of flours added to structured passion fruit and each stabilizer was observed through the linear behavior of the color analysis curves. In this case, the flatter and the lower the gradient, the better Structured passion fruit was prepared with 65% passion fruit the stabilizing effect provided by the additive. pulp (3.98 pH and 13.9 Brix) and 35% distilled water (100% The best results for the stabilizers studied were observed with mixture) and heated to 65 C. When the desired temperature was carrageenan and guar gum, which led to clouds with volumes of reached, a hydrocolloid mixture containing 1% alginate, 2% gelatin 10% and 15%, respectively, followed by the TF and HMP pectin, with and 3.5% of the additives under study was added. After homoge- suspensions of 30% and 37%, respectively. The other stabilizers nization, 35% sucrose, 10% glucose and 0.2% calcium phosphate promoted nectar cloud formation with a similar behavior to that of were added, with stirring for 10 min. The mixture was placed in a the control sample (without stabilizer), that is, the cloud volume petri dish with 50.0 mm diameter and 10.0 mm height and kept in a ranged from 50 to 57%. Xanthan gum was not effective in stabilizing refrigerator (10 C) for 24 h prior to analysis. the suspended solid particles in the nectar at the concentration The parameters of the structured fruit texture were evaluated in used in this study (0.1%), showing a higher final decantation vol- a CT3 Texture Analyzer (Brookfield, USA) using a cylindrical probe ume (65%). with 36 mm diameter (P/36), 60 s retention time, 1 mm/s test speed Additives in nectar often reduce sediment formation since they and 5 g load force. The parameters measured were firmness, increase the product viscosity (Sinchaipanit, Kerr & Chamchan, adhesion strength, adhesiveness and stress relaxation. 2013). The results reported herein show the action of different In addition, color analysis was performed using a MiniScan EZ hydrocolloid types when added to nectars and indicate that the digital colorimeter (Hunterlab, USA) and the color described using flours under study could provide a stabilizing option for juices (UF the CIELab system, as detailed in the previous section. and TF), although the degree of decantation was higher compared to carrageenan and guar gum. TF showed greater stabilizing power 2.4. Statistical analysis than UF; however, the low cost and ease of obtainment of UF also needs to be considered. Results were submitted to analysis of variance (ANOVA) and Genovese and Lozano (2000) investigated several stabilizer compared applying the Tukey test at 5% error probability, with the concentrations in apple juice. However, in order to ensure good aid of the SPSS (version 17.0) statistical package for Windows (SPSS, results in relation to xanthan gum, it was necessary to use a con- Chicago, USA). centration of 0.4e0.5%, which does not adhere to the Brazilian resolution Resoluçao~ de Diretoria Colegiada No. 8, 03 June 06, 2013 3. Results and discussion (Brazil, 2013), which allows a maximum of 0.2% of this additive in nectars. 3.1. Rheological analysis of hydrocolloids Sinchaipanit, kerrb, and chamchana (2013) assessed cloud sta- bility in carrot juice comparing various hydrocolloids, including The rheological flow of the hydrocolloids was determined by HMP pectin and guar gum, and observed that pectin was less evaluating the suspension in water. The rheological characteris- effective in preventing sedimentation, with moderate decantation tics varied according to gum type, since the gel formation char- occurring within eight days. For guar gum the same effect was acteristics of the gums differ according to the solvent and achieved only after 16 days. In addition, Babbar et al. (2015), temperature. All samples showed non-Newtonian behavior, i.e., assessed lychee juice stability using hydrocolloids, including pectin, there is a nonlinear relation between the shear stress and shear and found that LMP pectin had no significant effect on the cloud rate, resulting from structural changes caused by the shear stability. gradient applied. This behavior may be due to the fact that gums have a highly-folded long chain in the relaxed state. After 3.2.2. Emulsifying power of flours in mayonnaise and color analysis exposure to shear stress, unfolding occurs, which can lead to The textures of mayonnaise samples prepared with different thixotropy, and the liquid part of the product is released additives are shown in Table 1. (Carvalho et al., 2013). The observed plastic flow behavior is a Each hydrocolloid type has specific characteristics and these can desirable and appropriate property for bubblegum (jellybean) also vary depending on the type of product to which they are products, corroborating other results which indicated that the applied. Based on the results obtained in this study, it can be flours obtained from passion fruit peel are appropriate for this observed that the action of several gums in different concentrations type of product. affects the interaction of the compounds and the product emulsi- The flow properties obtained from each of the rheograms were fication. Izidoro, Sierakowski, Waszczynskyj, Haminiuk, and Scheer evaluated applying the k consistency index and n flow behavior (2007) reported that mayonnaise samples containing thickeners index, which were calculated using the Oswald-de Waele Equation and stabilizers are more rheologically stable. (Power Law) (Jones et al., 2009). The consistency index is deter- The mayonnaises samples did not differ in terms of adhesion mined through the mean viscosity based on points obtained from a strength. Regarding the hardness, the guar gum sample showed no flow curve and it varies according to the different gum interaction significant difference compared to the xanthan gum sample, forces. The behavior index showed that the gums under study had n although these differed from the other hydrocolloids. Adhesion values lower than 1, which means that they can be classified as strength and hardness are important parameters because they are pseudoplastic (Fester, Slatter, & Alderman, 2012). related to food chewing/swallowing (Szczesniak, 2002). In this E.M. Coelho et al. / Food Hydrocolloids 62 (2017) 158e164 161

Fig. 1. Settling behavior of solids suspended in passion fruit nectar with different additives. HMP ¼ high methoxyl pectins, LMP ¼ low methoxyl pectins, CAR ¼ carrageenan, GUA ¼ guar gum, XAN ¼ xanthan gum, UF ¼ untreated flour, TF ¼ treated flour, CTL ¼ control samples. respect, the performance of UF and TF was similar to that of other In the case of the thickeners studied, guar and xanthan gums additives. showed the best values for the product type in question. However, It was observed that the presence of hydrocolloids in mayon- for UF and TF the gumminess was similar to that provided by guar naise formulations primarily affected the product “cohesiveness”, gum. This finding is important because guar gum has the charac- and for some samples this parameter was 50% higher compared to teristic of forming dispersions by increasing the viscosity, acting as the control sample. Regarding the gumminess, the sample con- stabilizer in emulsions (Mudgil, Barak, & Khatkar, 2014). Thus, the taining carrageenan did not differ from the formulations with HMP, flours could also be used for this function. LMP, guar gum, UF and TF. Amin, Elbeltagy, Mustafa, and Khalil Mayonnaise samples prepared with guar gum also had higher (2014) observed higher cohesiveness and gumminess in mayon- adhesion strength compared with the UF, TF and control (CTL) naise samples to which guar and xanthan gums were added, due to samples, with values of 0.73; 0.63; 0.60 and 0.50 mJ, respectively. increased viscosity in emulsion. Based on the results obtained, the flours used in this study can

Table 1 Mean values of texture parameters for mayonnaise samples with different additives.

Samples Adhesion strength (g) Hardness (mm) Cohesiveness Gumminess (g) Adhesiveness(mJ)

HMP 3.33 ± 0.58a 3.81 ± 0.00a 2.37 ± 0.53abc 25.00 ± 1.00ab 0.23 ± 0.58d LMP 4.00 ± 0.00a 3.86 ± 0.11a 1.79 ± 0.50abc 19.00 ± 1.00ab 0.40 ± 0.10bcd CAR 5.00 ± 1.00a 3.70 ± 0.52a 3.09 ± 0.95a 14.67 ± 4.51a 0.33 ± 0.58cd GUA 5.00 ± 1.00a 2.87 ± 0.42b 2.81 ± 0.34ab 19.33 ± 8.50ab 0.73 ± 0.58 a XAN 4.67 ± 0.58a 3.47 ± 0.10ab 1.62 ± 0.45bc 12.33 ± 0.57b 0.40 ± 0.1bcd UF 5.33 ± 0.58a 3.61 ± 0.20a 1.23 ± 0.23c 19.33 ± 4.51ab 0.63 ± 0.58ab TF 5.33 ± 0.58a 3.74 ± 0.11a 2.30 ± 0.37abc 19.50 ± 5.00ab 0.60 ± 0.20abc CTL 3.67 ± 1.10a 3.81 ± 0.00a 1.00 ± 0.10c 7.67 ± 1.53b 0.50 ± 1.00abcd

Means followed by the same letters in the same column do not differ according to the Tukey test at 5% probability. HMP ¼ high methoxyl pectins, LMP ¼ low methoxyl pectins, CAR ¼ carrageenan, GUA ¼ guar gum, XAN ¼ xanthan gum, UF ¼ untreated flour, TF ¼ treated flour, CTL ¼ control sample. 162 E.M. Coelho et al. / Food Hydrocolloids 62 (2017) 158e164

Table 2 Table 5 Mean values of color parameters for mayonnaise samples with different additives. Mean values of color parameters for structured passion fruit.

Samples L* a* b* Samples L* a* b*

HMP 73.88 ± 0.20bc 2.95 ± 0.00a 15.31 ± 0.30a HMP 37.22 ± 0.64c 6.81 ± 0.33b 27.06 ± 2.18c LMP 72.39 ± 0.27d 2.82 ± 0.03ab 14.97 ± 0.53ab LMP 38.82 ± 0.85c 4.84 ± 0.13b 26.80 ± 1.15cd CAR 73.57 ± 0.11ab 2.53 ± 0.04cd 11.78 ± 0.25e CAR 34.93 ± 2.80cd 5.02 ± 0.14d 21.94 ± 2.14de GUA 73.31 ± 0.56abc 2.17 ± 0.07e 12.50 ± 0.07cd GUA 43.62 ± 3.89b 6.80 ± 0.39 b 35.20 ± 4.74b XAN 72.39 ± 0.38d 2.54 ± 0.22cd 12.17 ± 0.02cde XAN 70.99 ± 1.69a 5.55 ± 0.10 c 43.49 ± 1.30a UF 73.84 ± 0.09a 2.34 ± 0.04bc 11.85 ± 0.07de UF 32.32 ± 1.20d 7.00 ± 0.21b 19.02 ± 0.98ef TF 73.69 ± 0.03ab 2.62 ± 0.00bc 12.57 ± 0.40c TF 36.71 ± 0.52cd 7.53 ± 0.15a 24.57 ± 0.26cd CTL 72.88 ± 0.55cd 2.69 ± 0.28abc 14.33 ± 0.56b CTL 27.81 ± 0.65e 3.93 ± 0.11e 15.28 ± 0.94f

Means followed by the same letters in the same column do not differ according to Means followed by the same letters in the same column do not differ according to the Tukey test at 5% probability. HMP ¼ high methoxyl pectins, LMP ¼ low methoxyl the Tukey test at 5% probability. HMP ¼ high methoxyl pectins, LMP ¼ low methoxyl pectins, CAR ¼ carrageenan, GUA ¼ guar gum, XAN ¼ xanthan gum, UF ¼ untreated pectins, CAR ¼ carrageenan, GUA ¼ guar gum, XAN ¼ xanthan gum, UF ¼ untreated flour, TF ¼ treated flour, CTL ¼ control sample. flour, TF ¼ treated flour, CTL ¼ control sample.

Table 3 3.2.3. Assessment of thickening power in passion fruit syrup Mean values of color parameters for samples with different additives. In Table 3, the thickening power (viscosity) and water activity in

Thickening Viscosity (CSt) aw passion fruit syrup for ice cream of the hydrocolloids under study HMP 42.35 ± 1.17f 0.764 ± 0.00b can be observed. The syrup with the highest viscosity was that LMP 55.52 ± 1.29d 0.761 ± 0.00b containing xanthan gum, followed by TF, guar and UF. This indicates CAR 43.43 ± 0.95f 0.748 ± 0.00c that the potential of these flours as a thickening agent is significant, c d GUA 75.42 ± 0.91 0.700 ± 0.00 since they led to passion fruit syrup samples with higher viscosity ± a ± d XAN 337.84 1.01 0.728 0.00 when compared to other traditional commercial thickeners for this UF 74.46 ± 3.40c 0.746 ± 0.00c TF 143.99 ± 3.49b 0.730 ± 0.00d product, such as HMP and LMP pectins and carrageenan. CTL 50.13 ± 0.23e 0.791 ± 0.00a In the test syrup, the viscosity increased from 48% to 187%,

Means followed by the same letters in the same column do not differ according to respectively, when UF and TF were added, while high-methoxyl the Tukey test at 5% probability. HMP ¼ high methoxyl pectins, LMP ¼ low methoxyl and low-methoxyl pectins and carrageenan addition provided lit- pectins, CAR ¼ carrageenan, GUA ¼ guar gum, XAN ¼ xanthan gum, UF ¼ untreated tle or no increase in the product viscosity. One reason for the results flour, TF ¼ treated flour, CTL ¼ control sample. obtained for pectin may be the low concentration used (0.1%), since the manufacturer recommends from 0.3% to 1.0% for application in be considered to show similar behavior to guar and xanthan gums jams and jellies with soluble solid contents between 60 and 65%. In in mayonnaise processing. Thus, they could represent a suitable the case of carrageenan, the lack of a viscosity increase can be fi option to replace commercial emulsi ers. explained by the need for this additive to be associated with po- Table 2 shows the mean values for the color parameters L*, a* tassium or calcium ions in order to gel, besides this compound and b* for the mayonnaise samples prepared with different addi- being unstable under acidic conditions. This hydrocolloid is more > tives. All samples showed high lightness (L* 72) with a yellow tone suitable for products such as puddings, ice creams, yogurts and þ ( b*) and green pigment traces (-a*). The lightness (L*) of the UF others, due to its ability to form gels in low concentrations with fi sample did not differ signi cantly from that of TF, guar gum and milk, due to the presence of calcium (Saha & Bhattacharya, 2010). carrageenan. Amin et al. (2014) evaluated the color of mayonnaise However, Molina-Rubio, Cacas-Alencaster & Martínez-Padilla samples prepared from a mixture of soybean oil, xanthan gum and (2010) found that carrageenan was the best option out of the hy- guar gum, and observed lightness values ranging from 70.06 to drocolloids studied by the authors, modifying the rheological 84.09. properties of semi-liquid syrup for confectionery, which consisted The HMP, LMP and control sample (CTL) formulations showed of sucrose, high fructose corn syrup, gum, citric acid and water. The higher traces of the green pigment (-a*) and yellowness (-b*). same authors reported that samples with carrageenan added However, the lowest green trace was observed with the addition of showed higher values for all rheological properties studied, guar, and the lowest yellow trace was observed for samples with including viscosity. Vickers et al. (2015) assessed the thickening carrageenan, xanthan and UF added. Lower values were found by effect of 15 additives on a thin honey beverage, and noted that e Amin et al. (2014) both for a* ( 1.38 to 1.71) and b* (8.1 11.17). samples with calcium caseinate and high-methoxyl and low- Therefore, it is clear that the hydrocolloid added can affect the methoxyl pectin were relatively more active in terms of viscosity. mayonnaise color, which can be attributed to the particular char- Regarding the aw, the control sample provided the highest value acteristics of each additive.

Table 4 Means values of the texture parameters for structured passion fruit.

Samples Adhesiveness (mJ) Adhesion strength (g) Firmness (g) Stress relaxation (s)

HMP 1.4 ± 0.25a 90.5 ± 1.05a 3296 ± 2.00a 4.63 ± 1.23cd LMP 0.5 ± 0.4ab 10.5 ± 3.50c 1629 ± 1.38b 4.00 ± 0.5d CAR 1.1 ± 0.06ab 39.3 ± 1.90bc 424 ± 1.06c 4.27 ± 0.46d GUA 0.3 ± 0.02b 12.5 ± 3.50c 669 ± 1.39c 8.37 ± 1.11ab XAN 0.5 ± 0.46ab 28.7 ± 1.48bc 337 ± 2.32c 11.43 ± 1.78a UF 0.6 ± 0.3ab 14.5 ± 2.50c 1221 ± 2.54bc 6.30 ± 0.92bc TF 0.4 ± 0.1b 75 ± 4.50ab 2769 ± 0.82a 5.85 ± 0.15bc CTL 1.1 ± 0.56ab 41.3 ± 4.8ab 386 ± 0.49c 7.57 ± 1.62bc

Means followed by the same letters in the same column do not differ according to the Tukey test at 5% probability. HMP ¼ high methoxyl pectins, LMP ¼ low methoxyl pectins, CAR ¼ carrageenan, GUA ¼ guar gum, XAN ¼ xanthan gum, UF ¼ untreated flour, TF ¼ treated flour, CTL ¼ control sample. E.M. Coelho et al. / Food Hydrocolloids 62 (2017) 158e164 163

(0.97), showing a significant difference from the other samples, due Acknowledgements to the absence of hydrocolloids. Mixtures with guar, xanthan and TF provided lower values due to the interaction with the water The authors would like to acknowledge the Conselho Nacional available to act in the gel formation. Saha and Bhattacharya (2010) de Desenvolvimento Científico e Tecnologico - CNPq for granting a confirmed this phenomenon, reporting that hydrocolloids may scholarship. disperse in water and act as thickeners or change the viscosity, which is a known characteristic of these compounds. References

3.2.4. Assessment of gelling power Amin, M. H. H., Elbeltagy, A. E., Mustafa, M., & Khalil, A. H. (2014). Development of Table 4 shows the mean values for the texture of structured low fat mayonnaise containing different types and levels of hydrocolloid gum: Sensory optimization of low fat mayonnaise (different oils and gums). Journal of passion fruit prepared with different additives. All variables Agroalimentary Processes and Technologies, 20(1), 54e63. determined for this product showed significant differences. How- Ayala-Zavala, J. F., Vega-Veja, V., Rosas-Domínguez, C., Palafox-Carlos, H., Villa- ever, the parameter with the lowest variation between samples was Rodriguez, J. A., Wasim-Siddiqui, M. D., et al. (2011). Agro-industrial potential of exotic fruit byproducts as a source of food additives. Food Research International, adhesiveness, which is related to the tensile force required to 44, 1866e1874. separate food from the compression plate (Szczesniak, 2002). Azoubel, P. M., Araújo, A. J. De B., Oliveira, S. B. De, & Amorim, M. Da R. (2011). Structured fruits generally feature textures similar to that of Restructuring passiflora cincinnata fruit pulp: Influence of hydrocolloids. Food Science and Technology, 31(1), 160e166. jellybeans. Structured passion fruit prepared with HMP pectin and Babbar, N., Aggarwal, P., & Oberoi, H. S. (2015). Effect of addition of hydrocolloids on TF showed higher firmness when compared to the control sample the colloidal stability of litchi (Litchi chinensis sonn.) juice. Journal of Food Pro- (no additives), which was very fluid and did not show the jellybean cessing and Preservation, 39,183e189. Brazil - Agencia^ Nacional de Vigilancia^ Sanitaria (ANVISA). (2007). Atribuiçao~ de characteristic. Firmness is important for this type of product since it aditivos e seus limites maximos para a categoria de Alimentos 13: Molhos e Con- allows more time in the mouth, according to sensorial analysis. dimentos - Rdc n 04 de 15 de janeiro de 2007. Azoubel, Araújo, Oliveira, and Amorim (2011), who studied the Brazil - Ministro de Estado, Interino, da Agricultura, Pecuaria e Abastecimento (MAPA). (2003). Fixaçao~ dos Padroes~ de Identidade e Qualidade Gerais para Suco firmness of passion fruit (Passiflora cincinnata Mast), observed that tropical - In n 12, 4 de setembro de 2003. gelatin had a strong influence on the characteristics of this Brazil e Agencia^ Nacional de Vigilancia^ Sanitaria (ANVISA). (2013). Aprovaçao~ de uso parameter, since there was an increase in firmness with higher gum de aditivos alimentares para produtos de frutas e de vegetais e gelei de mocoto. º concentration. Other fruits have been used in studies on structure RDC n 8, 06 de março de 2013. Carvalho, F. C., Calixto, G., Hatakeyama, I. N., Luz, G. M., Gremiao,~ M. P. D., & development, in which various types of hydrocolloids and con- Chorilli, M. (2013). Rheological mechanical, and bioadhesive behavior of centrations were tested. Lins, Cavalcanti, Azoubel, Melo, and Maciel hydrogels to optimize skin delivery systems. Drug Derivate Industry Pharma- e (2014) studied structured yellow mombin fruit and reported ceutical, 39(11), 1750 1757. Codex AlimentariuseNormas Internacionales de los alimentos. (2015). Norma similar behaviors to that observed in this research. Grizotto, Bruns, General para los Aditivos Alimentarios (pp. 413e424). Aguirre, and Menezes (2007) assessed structured pineapple and Elleuch, M., Bedigian, D., Roiseux, O., Besbes, S., Blecker, C., & Attia, H. (2011). Di- noted that the firmness increased with increasing additive (alginate etary fibre and fibre-rich by-products of food processing: Characterisation, technological functionality and commercial applications: A review. Food and pectin) concentrations. The different behaviors observed for Chemistry, 124,411e421. the structured fruit texture can be explained by the gel properties, Fester, V., Slatter, P., & Alderman, N. (2012). Resitance coefficients for non- which vary according to types of hydrocolloid and product as well Newtonian flows in pipe fittings. In J. De Vicente (Ed.), Rheology (Vol. 1, pp. & 151e186). as the conditions of the process (Saha Bhattacharya, 2010). The Genovese, D. B., & Lozano, J. E. (2000). Effect of cloud particle characteristics on the sucrose and hydrocolloid concentrations along with the tempera- viscosity of cloudy apple juice. Journal of Food Science, 65(4), 641e645. ture are also important variables which affect the rheological state Grizotto, R. K., Bruns, R. E., Aguirre, J. M. de, & Menezes, H. C. de (2007). Techno- of the hydrocolloid gel (Marcotte et al., 2001). logical aspects for restructuring concentrated pineapple pulp. Food Science and Technology, 40, 759e765. The color results (L*, a* and b*) for the structured passion fruit Izidoro, D., Sierakowski, M. R., Waszczynskyj, N., Haminiuk, C. W. I., & Scheer, A. de samples are shown in Table 5, where it can be observed that the P. (2007). Sensory evaluation and rheological behavior of commercial mayon- structured control showed lower values than the other samples. naise. International Journal of Food Engineering, 3(1), 5. Jones, D. S., Bruschi, M. L., De Freitas, O., Gremiao,~ M. P. D., Lara, E. H. G., & Thus, the addition of hydrocolloids to the structured passion fruit Andrews, G. R. (2009). Rheological, mechanical and mucoadhesive properties of during preparation influences the final color of the product. In fact, thermoresponsive, bioadhesive binary mixtures composed of poloxamer 407 both the hydrocolloid type and concentration can affect the product and carbopol 974P designed as platforms for implantable drug delivery systems for use in the oral cavity. International Journal Prarmaceutical, 372,49e58. color (Azoubel et al., 2011). Kishore, K., Pathak, K. A., Shuklar, R., & Bhar, R. (2011). Effect of storage temperature Of the samples containing hydrocolloids that with xanthan gum on physic-chemical and sensory attributes of purple passion fruit (Passiflora showed the lightest color, which was visually perceived during the edulis Sims). Journal Food Science & Technology, 48, 484e488. Kliemann, E., Simas, K. N. de, Amante, E. R., Prudencio,^ E. S., Teofilo, R. F., product preparation, while the structured fruit samples containing Ferreira, M. M. C., et al. (2009). Optimisation of pectin acid extraction from UF were similar to those with TF and carrageenan. Regarding the a* passion fruit peel (Passiflora edulis flavicarpa) using response surface method- and b* values, despite the statistical difference between formula- ology. International Journal of Food Science & Technology, 44(3), 476e483. Lins, A. C. de A., Cavalcanti, D. T. de B., Azoubel, P. M., Melo, E. . de A., & tions, it is clear that all structured passion fruits had color charac- Maciel, M. I. S. (2014). Effect of hydrocolloids on the physicochemical charac- teristics in the yellow region (þb*), with traces of red (þa*). teristics of yellow mombin structured fruit. Food Science and Technology, 34(3), 456e463. Lopez-Vargas, J. H., Fernandez-L opez, J., Perez- Alvarez, J. A., & Viuda-Martos, M. 4. Conclusions (2013). Chemical, physico-chemical, technological, antibacterial and antioxi- dant properties of dietary fiber powder obtained from yellow passion fruit (Passiflora edulis var. flavicarpa) co-products. Food Research International, 51, Based on the results obtain in this study, passion fruit peel 756e763. flours, treated and untreated, can be used to replace the commer- Marcotte, M. 'le, Hoshahili, A. R. T., & Ramaswamy, H. S. (2001). Rheological prop- cial hydrocolloids considered herein. These flours can be obtained erties of selected hydrocolloids as a function of concentration and temperature. Food Research International, 34, 695e703. through simple and low cost procedures and had similar techno- Martínez, R., Torres, P., Meneses, M. A., Figueroa, J. G., Perez- Alvarez, J. A., & Viuda- logical characteristics regarding stabilizing, emulsifying, thickening Martos, M. (2012). Chemical, technological and in vitro antioxidant properties and gelling power. Furthermore, it was noted that the treated of mango, guava, pineapple and passion fruit dietary fibre concentrate. Food e fl Chemistry, 135, 1520 1526. passion fruit peel our had higher stabilizer, thickening and gelling Molina-Rubio, M. P., Casas-Alencaster, N. B., & Martínez-Padilla, L. P. (2010). Effect of power when compared to untreated flour. formulation and processing conditions on the rheological and textural 164 E.M. Coelho et al. / Food Hydrocolloids 62 (2017) 158e164

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