Vegetable oils and fats may be used as cheap substitutes for milk fat to manufacture imitation cheese or imitation ice cream. In this study, 400？MHz nuclear magnetic resonance (NMR) spectroscopy of the fat fraction of the products was used in the context of food surveillance to validate the labeling of milk-based products. For sample preparation, the fat was extracted using an automated Weibull-Stoldt methodology. Using principal component analysis (PCA), imitation products can be easily detected. In both cheese and ice cream, a differentiation according to the type of raw material (milk fat and vegetable fat) was possible. The loadings plot shows that imitation products were distinguishable by differences in their fatty acid ratios. Furthermore, a differentiation of several types of cheese (Edamer, Gouda, Emmentaler, and Feta) was possible. Quantitative data regarding the composition of the investigated products can also be predicted from the same spectra using partial least squares (PLS) regression. The models obtained for 13 compounds in cheese ( 0.75–0.95) and 17 compounds in ice cream ( 0.83–0.99) (e.g., fatty acids and esters) were suitable for a screening analysis. NMR spectroscopy was judged as suitable for the routine analysis of dairy products based on milk or on vegetable fat substitutes. 1. Introduction Due to industry efforts to provide low-cost foods or due to general ethical considerations against cow’s milk consumption [1], imitation dairy products have recently appeared on the market [2–5]. Cheese analogues or imitation cheese are cheese-like products in which milk fat, milk protein, or both are partially or completely replaced with nonmilk-based components such as soy [2], starch [6], or vegetable replacers [3]. Other alternative products for consumers with cow milk intolerance [7] based on goat [8, 9] or sheep milk [9] can also be found on the market. Vegetable oils and fats are most commonly used as cheap substitutes for milk fat to manufacture imitation cheese or imitation ice cream. While not being harmful to health, the imitation products may be of lesser nutritional quality (e.g., by lower calcium content) and contain several artificial flavors and food colors [10]. Unfortunately, such imitation products may be offered without the necessary labeling, which is a deception of the consumer. Pizza topping is a good example of such a possibility [10]. It has therefore become necessary to develop a reliable technique able to detect such products in the market. Chromatographic methods are the most popular choice for analysis of organic
References
[1]
A. Beardsworth and T. Keil, “The vegetarian option: varieties, conversions, motives and careers,” Sociological Review, vol. 40, pp. 253–293, 1992.
[2]
N. Sutar, P. P. Sutar, and G. Singh, “Evaluation of different soybean varieties for manufacture of soy ice cream,” International Journal of Dairy Technology, vol. 63, no. 1, pp. 136–142, 2010.
[3]
A. I. W. Rosnani, I. N. Aini, A. M. M. Yazid, and M. H. Dzulkifly, “Flow properties of ice cream mix prepared from palm oil: anhydrous milk fat blends,” Pakistan Journal of Biological Sciences, vol. 10, no. 10, pp. 1691–1696, 2007.
[4]
H. Bachmann, “Cheese analogues: a review,” International Dairy Journal, vol. 11, no. 4–7, pp. 505–515, 2001.
[5]
C. R. Cunha, A. I. Dias, and W. H. Viotto, “Microstructure, texture, colour and sensory evaluation of a spreadable processed cheese analogue made with vegetable fat,” Food Research International, vol. 43, no. 3, pp. 723–729, 2010.
[6]
N. Noronha, E. D. O'Riordan, and M. O'Sullivan, “Replacement of fat with functional fibre in imitation cheese,” International Dairy Journal, vol. 17, no. 9, pp. 1073–1082, 2007.
[7]
M. Montalto, V. Curigliano, L. Santoro et al., “Management and treatment of lactose malabsorption,” World Journal of Gastroenterology, vol. 12, no. 2, pp. 187–191, 2006.
[8]
D. Sanchez-Macias, M. Fresno, I. Moreno-Indias et al., “Physicochemical analysis of full-fat, reduced-fat, and low-fat artisan-style goat cheese,” Journal of Dairy Science, vol. 93, no. 9, pp. 3950–3956, 2010.
[9]
K. Raynal-Ljutovac, G. Lagriffoul, P. Paccard, I. Guillet, and Y. Chilliard, “Composition of goat and sheep milk products: an update,” Small Ruminant Research, vol. 79, no. 1, pp. 57–72, 2008.
[10]
A. Rehm, “K？se ist nicht gleich K？se,” Ern？hrung im Fokus, vol. 11, pp. 538–541, 2011.
[11]
I. V. Wolf, M. C. Perotti, S. M. Bernal, and C. A. Zalazar, “Study of the chemical composition, proteolysis, lipolysis and volatile compounds profile of commercial Reggianito Argentino cheese: characterization of Reggianito Argentino cheese,” Food Research International, vol. 43, no. 4, pp. 1204–1211, 2010.
[12]
J. M. Poveda, E. Sánchez-Palomo, M. S. Pérez-Coello, and L. Cabezas, “Volatile composition, olfactometry profile and sensory evaluation of semi-hard Spanish goat cheeses,” Dairy Science and Technology, vol. 88, no. 3, pp. 355–367, 2008.
[13]
A. A. Hayaloglu, E. Y. Brechany, K. C. Deegan, and P. L. H. McSweeney, “Characterization of the chemistry, biochemistry and volatile profile of Kuflu cheese, a mould-ripened variety,” Lebensmittel-Wissenschaft & Technologie, vol. 41, no. 7, pp. 1323–1334, 2008.
[14]
S. Bonetta, J. D. Co？sson, D. Barile et al., “Microbiological and chemical characterization of a typical Italian cheese: Robiola di Roccaverano,” Journal of Agricultural and Food Chemistry, vol. 56, no. 16, pp. 7223–7230, 2008.
[15]
S. Panseri, I. Giani, T. Mentasti, F. Bellagamba, F. Caprino, and V. M. Moretti, “Determination of flavour compounds in a mountain cheese by headspace sorptive extraction-thermal desorption-capillary gas chromatography-mass spectrometry,” Lebensmittel-Wissenschaft & Technologie, vol. 41, no. 2, pp. 185–192, 2008.
[16]
A. Castell-Palou, C. Rosselló, A. Femenia, and S. Simal, “Application of multivariate statistical analysis to chemical, physical and sensory characteristics of Majorcan cheese,” International Journal of Food Engineering, vol. 6, no. 2, article 9, 2010.
[17]
S. Hauff and W. Vetter, “Quantification of branched chain fatty acids in polar and neutral lipids of cheese and fish samples,” Journal of Agricultural and Food Chemistry, vol. 58, no. 2, pp. 707–712, 2010.
[18]
A. Subramanian, W. J. Harper, and L. E. Rodriguez-Saona, “Rapid prediction of composition and flavor quality of cheddar cheese using ATR-FTIR spectroscopy,” Journal of Food Science, vol. 74, no. 3, pp. C292–C297, 2009.
[19]
N. A. Kocaoglu-Vurma, A. Eliardi, M. A. Drake, L. E. Rodriguez-Saona, and W. J. Harper, “Rapid profiling of swiss cheese by attenuated total reflectance (ATR) infrared spectroscopy and descriptive sensory analysis,” Journal of Food Science, vol. 74, no. 6, pp. S232–S239, 2009.
[20]
C. M. Andersen, M. B. Fr？st, and N. Viereck, “Spectroscopic characterization of low- and non-fat cream cheeses,” International Dairy Journal, vol. 20, no. 1, pp. 32–39, 2010.
[21]
A. Lucas, D. Andueza, E. Rock, and B. Martin, “Prediction of dry matter, fat, pH, vitamins, minerals, carotenoids, total antioxidant capacity, and color in fresh and freeze-dried cheeses by visible-near-infrared reflectance spectroscopy,” Journal of Agricultural and Food Chemistry, vol. 56, no. 16, pp. 6801–6808, 2008.
[22]
G. Cozzi, J. Ferlito, G. Pasini, B. Contiero, and F. Gottardo, “Application of near-infrared spectroscopy as an alternative to chemical and color analysis to discriminate the production chains of Asiago d'Allevo cheese,” Journal of Agricultural and Food Chemistry, vol. 57, no. 24, pp. 11449–11454, 2009.
[23]
R. Moreno-Rojas, P. J. Sánchez-Segarra, F. Cámara-Martos, and M. A. Amaro-López, “Multivariate analysis techniques as tools for categorization of Southern Spanish cheeses: nutritional composition and mineral content,” European Food Research and Technology, vol. 231, no. 6, pp. 841–851, 2010.
[24]
A. Lante, G. Lomolino, M. Cagnin, and P. Spettoli, “Content and characterisation of minerals in milk and in Crescenza and Squacquerone Italian fresh cheeses by ICP-OES,” Food Control, vol. 17, no. 3, pp. 229–233, 2006.
[25]
M. A. Brescia, M. Monfreda, A. Buccolieri, and C. Carrino, “Characterisation of the geographical origin of buffalo milk and mozzarella cheese by means of analytical and spectroscopic determinations,” Food Chemistry, vol. 89, no. 1, pp. 139–147, 2005.
[26]
G. Le Gall and I. J. Colquhoun, Food Authenticity and Traceability, M. Lees eds, Woodhead Publishing, Cambridge, UK, 2003.
[27]
D. W. Lachenmeier, W. Frank, E. Humpfer et al., “Quality control of beer using high-resolution nuclear magnetic resonance spectroscopy and multivariate analysis,” European Food Research and Technology, vol. 220, no. 2, pp. 215–221, 2005.
[28]
P. S. Belton, I. J. Colquhoun, E. K. Kemsley et al., “Application of chemometrics to the 1H NMR spectra of apple juices: discrimination between apple varieties,” Food Chemistry, vol. 61, no. 1-2, pp. 207–213, 1998.
[29]
L. Forveille, J. Vercauteren, and D. N. Rutledge, “Multivariate statistical analysis of two-dimensional NMR data to differentiate grapevine cultivars and clones,” Food Chemistry, vol. 57, no. 3, pp. 441–450, 1996.
[30]
D. W. Lachenmeier, H. Eberhard, F. Fang et al., “NMR-spectroscopy for nontargeted screening and simultaneous quantification of health-relevant compounds in foods: the example of melamine,” Journal of Agricultural and Food Chemistry, vol. 57, no. 16, pp. 7194–7199, 2009.
[31]
H. K？bler, Y. B. Monakhova, T. Kuballa et al., “Nuclear magnetic resonance spectroscopy and chemometrics to identify pine nuts that cause taste disturbance,” Journal of Agricultural and Food Chemistry, vol. 59, no. 13, pp. 6877–6881, 2011.
[32]
R. Lamanna, I. Piscioneri, V. Romanelli, and N. Sharma, “A preliminary study of soft cheese degradation in different packaging conditions by 1H-NMR,” Magnetic Resonance in Chemistry, vol. 46, no. 9, pp. 828–831, 2008.
[33]
D. Rodrigues, C. H. Santos, T. A. P. Rocha-Santos, A. M. Gomes, B. J. Goodfellow, and A. C. Freitas, “Metabolic profiling of potential probiotic or synbiotic cheeses by nuclear magnetic resonance (NMR) spectroscopy,” Journal of Agricultural and Food Chemistry, vol. 59, no. 9, pp. 4955–4961, 2011.
[34]
R. Consonni and L. R. Cagliani, “Ripening and geographical characterization of Parmigiano Reggiano cheese by 1H NMR spectroscopy,” Talanta, vol. 76, no. 1, pp. 200–205, 2008.
[35]
S. De Angelis Curtis, R. Curini, M. Delfini, E. Brosio, F. D'Ascenzo, and B. Bocca, “Amino acid profile in the ripening of Grana Padano cheese: a NMR study,” Food Chemistry, vol. 71, no. 4, pp. 495–502, 2000.
[36]
E. Schievano, K. Guardini, and S. Mammi, “Fast determination of histamine in cheese by nuclear magnetic resonance (NMR),” Journal of Agricultural and Food Chemistry, vol. 57, no. 7, pp. 2647–2652, 2009.
[37]
M. Gobet, C. Rondeau-Mouro, S. Buchin et al., “Distribution and mobility of phosphates and sodium ions in cheese by solid-state 31P and double-quantum filtered 23Na NMR spectroscopy,” Magnetic Resonance in Chemistry, vol. 48, no. 4, pp. 297–303, 2010.
[38]
A. Castell-Palou, C. Rosselló, A. Femenia, J. Bon, and S. Simal, “Moisture profiles in cheese drying determined by TD-NMR: mathematical modeling of mass transfer,” Journal of Food Engineering, vol. 104, no. 4, pp. 525–531, 2011.
[39]
T. Lucas, D. Le Ray, P. Barey, and F. Mariette, “NMR assessment of ice cream: effect of formulation on liquid and solid fat,” International Dairy Journal, vol. 15, no. 12, pp. 1225–1233, 2005.
[40]
T. Lucas, M. Wagener, P. Barey, and F. Mariette, “NMR assessment of mix and ice cream. Effect of formulation on liquid water and ice,” International Dairy Journal, vol. 15, no. 10, pp. 1064–1073, 2005.
[41]
F. Mariette and T. Lucas, “NMR signal analysis to attribute the components to the solid/liquid phases present in mixes and ice creams,” Journal of Agricultural and Food Chemistry, vol. 53, no. 5, pp. 1317–1327, 2005.
[42]
G. S. Remaud, Y. Martin, G. G. Martin, and G. J. Martin, “Detection of sophisticated adulterations of natural vanilla flavors and extracts: application of the SNIF-NMR to method vanillin and p-hydroxybenzaldehyde,” Journal of Agricultural and Food Chemistry, vol. 45, no. 3, pp. 859–866, 1997.
[43]
F. Locci, R. Ghiglietti, S. Francolino et al., “Detection of cow milk in cooked buffalo Mozzarella used as Pizza topping,” Food Chemistry, vol. 107, no. 3, pp. 1337–1341, 2008.
[44]
J. Fontecha, I. Mayo, G. Toledano, and M. Juárez, “Triacylglycerol composition of protected designation of origin cheeses during ripening. Authenticity of milk fat,” Journal of Dairy Science, vol. 89, no. 3, pp. 882–887, 2006.
[45]
G. Knothe and J. A. Kenar, “Determination of the fatty acid profile by 1H-NMR spectroscopy,” European Journal of Lipid Science and Technology, vol. 106, no. 2, pp. 88–96, 2004.
[46]
E. Schievano, G. Pasini, G. Cozzi, and S. Mammi, “Identification of the production chain of Asiago d'Allevo cheese by nuclear magnetic resonance spectroscopy and principal component analysis,” Journal of Agricultural and Food Chemistry, vol. 56, no. 16, pp. 7208–7214, 2008.
[47]
R. Karoui and J. De Baerdemaeker, “A review of the analytical methods coupled with chemometric tools for the determination of the quality and identity of dairy products,” Food Chemistry, vol. 102, no. 3, pp. 621–640, 2007.
[48]
L. Shintu and S. Caldarelli, “Toward the determination of the geographical origin of emmental(er) cheese via high resolution MAS NMR: a preliminary investigation,” Journal of Agricultural and Food Chemistry, vol. 54, no. 12, pp. 4148–4154, 2006.
[49]
Y. B. Monakhova, T. Kuballa, J. Leitz, et al., “NMR spectroscopy as a screening tool to validate nutrition labeling of milk, lactose-free milk, and milk substitutes based on soy and grains,” Dairy Science and Technology, vol. 92, no. 2, pp. 109–120, 2012.
