The Aquaphotomics Approach as a Tool for Studying the Influence of Food Coating Materials on Cheese and Winter Melon Samples

Abstract

Food packaging and coatings have the well-known and established functions of containment, protection and handling facilitation of the food packaged inside. Fast methods able to classify, sort and identify the quality and the stability characteristics associated with the various packaging and coating materials are required along the food chain in order to validate their properties. Innovative products deriving from organic polymers, recently submitted for Italian patent (no. 102015000018950), were used as coatings both in the food industry for two types of cheese (provola and caciotta) and in postharvest management to modulate fruit ripening of winter melons during storage at 13°C. This work aimed at studying the effect of the differences in performance and permeability properties of the coatings after their application and during the ripening and storage period by using near infrared spectroscopy and exploiting the aquaphotomics approach, where information on the absorption bands can provide a distinct knowledge of water vibrations and intrinsic interactions between water and other components of the aqueous system. Applying multivariate spectral analysis, it was found that changes of water matrix under perturbation reflect other molecules surrounded by water, allowing the identification of specific fingerprints associated with coating characteristics and with the ripening/storage trends. Each coating generated a specific fingerprint for the same product suggesting that aquagrams could be a useful and fast procedure able to distinguish the effects of different coating materials on the same matrices. It was also proved that starting from similar aquagrams it was possible to follow and monitor the storage trends.

Influence of innovative coatings on salami ripening assessed by near infrared spectroscopy and aquaphotomics

“…1 Also packaging significantly affects a w and Liaros et al 31 found that all packaged low-fat sausages had higher a w values than the nonpackaged low-fat control sausages, suggesting that the above changes in a w are due to moisture losses as a significant high negative correlation (r ¼ À0.901, p < 0.01) was found between the water activity and weight loss of low-fat fermented sausages. Similarly, Cattaneo et al 11 found changes in the water matrix of provola and caciotta cheese treated with different coatings which were in agreement with both weight loss and texture profile analyses. Vanoli et al 18 also found changes in water organization in apples with different sensory texture characteristics as mealy apples were characterized by a preponderance of water structure with weakhydrogen bonds (1364-1382 nm), whereas the WASP of crispy and juicy apples indicated the presence of more organized water structures (dimers, trimers) with medium-strong hydrogen bonds (1410-1492 nm).…”

“…1344 nm, 1364 nm, 1372 nm, 1382 nm, 1398 nm, 1410 nm, 1438 nm, 1444 nm, 1464 nm, 1474 nm, 1492 nm and 1518 nm and calculated according to Cattaneo et al. 11 .…”

“…13 Aquagrams, which display normalized water absorbance values from different sample groups, were built on pre-treated NIR spectra (MSC followed by Savitsky-Golay second derivative with 15 points, second-order polynomial) using the 12 characteristic water absorption wavelengths, i.e. 1344 nm, 1364 nm, 1372 nm, 1382 nm, 1398 nm, 1410 nm, 1438 nm, 1444 nm, 1464 nm, 1474 nm, 1492 nm and 1518 nm and calculated according to Cattaneo et al 11 .…”

“…7 NIR showed satisfactory predictive ability for water activity and moisture content and for chemical composition (fat and protein contents, fatty acids and free amino acid composition and sodium content) in commercial processed meat products, but had limited ability in estimating technological and sensory attributes. [7][8][9][10] Recently, Cattaneo et al 11 investigated the influence of different type of coatings on the ripening of cheese and melon by studying the water status of the products through the aquaphotomics approach. Aquaphotomics is a novel scientific discipline that investigates the water-light interactions in biological systems coupling NIR measurements and multivariate spectral analysis, because changes in the water matrix reflect, like a mirror, the rest of the molecules surrounded by water.…”

“…Recently, Cattaneo et al. 11 investigated the influence of different type of coatings on the ripening of cheese and melon by studying the water status of the products through the aquaphotomics approach. Aquaphotomics is a novel scientific discipline that investigates the water–light interactions in biological systems coupling NIR measurements and multivariate spectral analysis, because changes in the water matrix reflect, like a mirror, the rest of the molecules surrounded by water.…”