Physicochemical and sensorial properties of grapefruit jams as affected by processing

Jam is an effective and tasty way of preserving fruit. Jam processing procedures as well as storage conditions and duration are important factors for jam quality. Traditional jam processing involves the application of severe thermal treatments that imply undesirable changes in the product quality characteristics such as colour, texture, flavour and nutritional and functional value. In this work, osmotic dehydration (OD) and/or microwave energy (MW) was proven as adequate to obtain jam with the typical characteristics of water content, degree Brix, pH and water activity of jam obtained by conventional thermal heating. The sensory evaluation carried out to compare the product showed that samples submitted to more intense heating treatments (conventional or MW) had significantly higher scores in colour saturation, brightness, grapefruit taste and extensibility than OD or OD+MW ones. As deduced from the obtained results, OD treatment prevents grapefruit colour changes, and mild MW heating contributes to increase the consistency and decrease the extensibility of the obtained jam. In this way, OD+MW jam was preferred by assessors mainly due to its higher consistency. The sample obtained by this procedure was stable during storage.The authors would like to thank the Ministerio de Educacion y Ciencia for the financial support given throughout the Project AGL 2005-05994. The language revision of this paper was funded by the Universidad Politecnica de Valencia, Spain.Igual Ramo, M.; García Martínez, EM.; Camacho Vidal, MM.; Martínez Navarrete, N. (2013). Physicochemical and sensorial properties of grapefruit jams as affected by processing. Food and Bioprocess Technology. 6(1):177-185. https://doi.org/10.1007/s11947-011-0696-2S17718561AENOR (2009). Sensory analysis. Methodology. Paired comparison test. UNE-EN-ISO 5495.AOAC. (2000). Official methods of analysis of AOAC International (17th ed.). Gaithersburg: AOAC International.Baker, R.-A., Berry, N., Hui, Y.-H., & Barrett, D.-M. (2005). Fruit preserves and jams. In Processing fruits: science and technology (2nd ed., pp. 113–125). Boca Ratón: CRC Press.Bodart, M., de Peñaranda, R., Deneyer, A., & Flamant, G. (2008). Photometry and colorimetry characterisation of materials in daylighting evaluation tools. Building and Environment, 43, 2046–2058.BOE (1990). Real Decreto 670/1990, de 25 de mayo, por el que se aprueba la norma de calidad para confituras, jaleas y marmalade de frutas, crema de castañas y mermelada de frutas. BOE Nº 130 (31/5/1990), 15140–15144.Bourne, M. (1982). Food texture and viscosity—concept and measurement. New York: Academic.Cañumir, J.-A., Celis, J.-E., Brujin, J., & Vidal, L. (2002). Pasteurisation of apple juice by using microwaves. Lebensmittel-Wissenschaft und Technologie, 35, 389–392.Contreras, C., Martín-Esparza, M.-E., Martínez-Navarrete, N., & Chiralt, A. (2008). Influence of microwave application on convective drying: effects on drying kinetics, and optical and mechanical properties of apple and strawberry. Journal of Food Engineering, 88, 55–64.Dervisi, P., Lamb, J., & Zabetakis, I. (2001). High pressure processing in jam manufacture: effects on textural and color properties. Food Chemistry, 73, 85–91.Deyhim, F., Garica, K., Lopez, E., Gonzalez, J., Ino, S., Garcia, M., et al. (2006). Citrus juice modulates bone strength in male senescent rat model of osteoporosis. Nutrition, 22(5), 559–563.García-Martínez, E., Ruiz-Diaz, G., Martínez-Monzó, J., Camacho, M.-M., Martínez-Navarrete, N., & Chiralt, A. (2002). Jam manufacture with osmodehydrated fruit. Food Research International, 35, 301–306.Igual, M., García-Martínez, E., Camacho, M.-M., & Martínez-Navarrete, N. (2010a). Effect of thermal treatment and storage on the stability of organic acids and the functional value of grapefruit juice. Food Chemistry, 118, 291–299.Igual, M., Contreras, C., & Martínez-Navarrete, N. (2010b). Non-conventional techniques to obtain grapefruit jam. Innovative Food Science and Emerging Technologies, 11(2), 335–341.Meilgaard, M., Civille, G.-V., & Carr, B.-T. (1999). Attribute differences test. Pairwise ranking test: Friedman analysis. Sensory evaluation techniques (pp. 103–106). Boca Ratón: CRC Press.Moraga, M.-J., Moraga, G., Fito, P. J., & Martínez-Navarrete, N. (2009). Effect of vacuum impregnation with calcium lactate on the osmotic dehydration kinetics and quality of osmodehydrated grapefruit. Journal of Food Engineering, 90, 372–379.Nikdel, S., Chen, C., Parish, M., MacKellar, D., & Friedrich, L. (1993). Pasteurization of citrus juice with microwaves energy in a continuous-flow unit. Journal of Agricultural and Food Chemistry, 41, 2116–2119.Poulose, S.-M., Harris, E.-D., & Patil, B.-S. (2005). Citrus limonoids induce apoptosis in human neuroblastoma cells and have radical scavenging activity. Journal of Nutrition, 135, 870–877.Sanchez-Moreno, C., Plaza, L., De Ancos, B., & Cano, M.-P. (2003). Quantitative bioactive compounds assessment and their relative contribution to the antioxidant capacity of commercial orange juices. Journal of the Science of Food and Agriculture, 83, 430–439.Shi, X.-Q., Chiralt, A., Fito, P., Serra, J., Escoin, C., & Gasque, L. (1996). Application of osmotic dehydration technology on jam processing. Drying Technology, 14(3&4), 841–857.Tárrega, A., & Costell, E. (2007). Colour and consistency of semi-solid dairy desserts: instrumental and sensory measurements. Journal of Food Engineering, 78, 655–661.Vanamala, J., Reddivari, L., Yoo, K.-S., Pike, L.-M., & Patil, B.-S. (2006). Variation in the content of bioactive flavonoid in different brands of orange and grapefruit juices. Journal of Food Composition and Analysis, 19(2–3), 157–166.Wicklund, T., Rosenfeld, H.-J., Martinsen, B.-K., Sundførb, M.-W., Lea, P., Bruun, T., et al. (2005). Antioxidant capacity and colour of strawberry jam as influenced by cultivar and storage conditions. LWT-Food Science and Technology, 38(4), 387–391.Yu, L.-L., Zhou, K.-K., & Parry, J. (2005). Antioxidant properties of cold-pressed black caraway, carrot, cranberry, and hemp seed oils. Food Chemistry, 91, 723–729

Experiences of the implementation and operation of hazard analysis critical control points in the food service sector

This study explored experiences of implementation and operation of hazard analysis critical control points (HACCP) in the foodservice sector through in-depth interviews with seven foodservice outlets in the South East of England. Experiences highlighted a number of barriers to the successful implementation and operation of HACCP, and also perceived benefits. Barriers included difficulties identifying hazards, inadequate knowledge, time-related issues relating to monitoring and recording, excessive documentation, convincing staff of the importance of the system, and increased costs. Perceived benefits included protecting the business from otherwise unforeseen problems and providing evidence of 'due diligence'. There was, however, an attitude of compliance, rather than true recognition of the value of the system. © 2004 Elsevier Ltd. All rights reserved

Experiences of the implementation and operation of hazard analysis critical control points in the food service sector

This study explored experiences of implementation and operation of hazard analysis critical control points (HACCP) in the foodservice sector through in-depth interviews with seven foodservice outlets in the South East of England. Experiences highlighted a number of barriers to the successful implementation and operation of HACCP, and also perceived benefits. Barriers included difficulties identifying hazards, inadequate knowledge, time-related issues relating to monitoring and recording, excessive documentation, convincing staff of the importance of the system, and increased costs. Perceived benefits included protecting the business from otherwise unforeseen problems and providing evidence of 'due diligence'. There was, however, an attitude of compliance, rather than true recognition of the value of the system. © 2004 Elsevier Ltd. All rights reserved

Food safety management

In-flight catering is a central part of these strategies at all levels: be they customer satisfaction, marketing, operations or logistics

Food safety management

In-flight catering is a central part of these strategies at all levels: be they customer satisfaction, marketing, operations or logistics

Synthesis and chemistry of diphenyl-2-pyridylphosphine complexes of palladium(0). X-Ray characterisation of Pd(Ph2Ppy)2(?2-DMAD) and trans-Pd(Ph2Ppy)2(PhC?CH2)(CF3CO2)

The zerovalent complexes Pd(Ph2Ppy)31 and Pd(Ph2Ppy)2(dba) 2, where Ph2Ppy is diphenyl-2-pyridylphosphine and dba = trans,trans-dibenzylideneacetone, have been synthesized and characterised. Reactions of 1 with alkynes have been studied and the dimethyl acetylenedicarboxylate complex Pd(Ph2Ppy)2(η2-DMAD) 3, where DMAD is dimethyl acetylenedicarboxylate, isolated and structurally characterised. The complexes trans-Pd(Ph2Ppy)2(PhC[double bond, length half m-dash]CH2)X, X = CF3CO2−4 or Cl−5, and trans-Pd(Ph2Ppy)2{CO(CH3)C[double bond, length half m-dash]CH2}Cl 6 result from oxidative addition of phenylacetylene/CF3CO2H, phenylacetylene/Et3NHCl and methacryloyl chloride respectively to 1, and the crystal structure of 4 is presented. The alkenyl ligand is bound to palladium through the α carbon in 4. Insertions into the M–C bond of the vinyl complexes have been studied. No isolable insertion product is obtained with carbon monoxide although the complex is active for the catalytic alkoxycarbonylation of phenylacetylene to 2-phenylpropenoate. Propadiene inserts into the Pd–C bond in 4 to give the cationic π-allyl complex [Pd(Ph2Ppy)2{η3-C3H4C(Ph)[double bond, length half m-dash]CH2}][CF3CO2] 7. The complex Pd(Ph2Ppy)3 is found to catalyse the vinylation of Ph2Ppy to the corresponding 2-propenylphosphonium trifluoromethanesulfonate

Comments on the catalytic alkoxycarbonylation of alkynes

The alkoxycarbonyl complexes Pd(Ph2Ppy)2(CO2R)(OAc) where Ph2Ppy is 2-pyridyldiphenylphosphine and R = Me 1, Et 2, i-Pr 3 have been prepared from Pd(OAc)2 and Ph2Ppy in ethanol solution under an atmosphere of CO. Increasing the CO pressure favours the formation of palladium carbonyl species. In the presence of 2 mol equivalents of CF3CO2H, the complex Pd(Ph2Ppy)2(CO2CH3)(CF3CO2) 4 is isolated from methanol. Pd(Ph2Ppy)2(CO2CH3)Cl 5 has been obtained by the reaction of Pd(Ph2Ppy)2Cl2 with NaOCH3 in the presence of CO. 1 and 5 have been crystallographicaly characterised as trans isomers, a geometry confirmed for all the complexes by 13C NMR. The reactivity of the complexes toward alkynes and propadiene has been investigated and the π-allyl complex [Pd(Ph2Ppy)2{η3-C3H4C(CH3)[double bond, length half m-dash]CH2}][O2CCF3] 8 isolated and structurally characterised