Papers by Ernestina Casiraghi
Introduction: In recent years many investigators applied various techniques to identify meat spec... more Introduction: In recent years many investigators applied various techniques to identify meat species, but the development of an easy, rapid and sensitive method is still needed. The aim of this work was to investigate the potential of UV-VIS, NIR and MIR spectroscopy to detect bovine meat adulteration with turkey meat. The use of several chemometric techniques were explored to determine the effect on method sensitivity. Materials and Methods: Eleven different lots of beef and turkey meat from different animals were used. Each lot was separately minced and then used to prepare in duplicate 7 mixtures (450 g each) of bovine meat added with different percentages of turkey meat, ranging from 5 to 50%. The 154 mixtures thus obtained and the 44 meat samples of 100% beef and 100% turkey were analyzed by means of UV-VIS, NIR and MIR spectroscopy. The UV-VIS spectra (200-780 nm) were collected using an integrative sphere working in diffuse reflectance. The NIR and MIR spectra were recorded using an FT-NIR spectrometer (12500-3900 cm-1) and an FT-IR spectrometer equipped with an ATR cell (400-700 cm-1), respectively. The spectral data, standardized by different pretreatments, were processed using PCA and classification techniques (LDA, PLS-DA) applied after feature selection by the algorithm SELECT. Results and Discussion: For all spectroscopy techniques used, clusters have been identified in the PCA score plots obtained from spectra, that allowed distinction between adulterated and not-adulterated bovine meat. The best distinct percentages of adulteration were those ranging from 30 to 50%. Classification results showed that samples belonging to a particular adulteration level could be correctly classified. The most accurate results were obtained with either feature selection or data compression. Conclusion: The potential of UV-VIS, NIR, and MIR spectroscopy techniques to distinguish between adulterated and not-adulterated beef meat was demonstrated. Moreover, the use of chemometric strategies applied to fused UV-VIS, NIR and MIR spectra could represent an effective method for classification of bovine meat on the basis of adulteration level. Novelty statement: This study represents a significant basis for developing an easy, rapid and sensitive spectroscopic method to identify bovine meat adulteration with lower grade substitutes. Summary: UV-VIS, NIR and MIR spectroscopy techniques, combined with the suitable chemometric strategies, could be useful tools for the rapid and easy identification of bovine meat adulteration with lower grade substitutes, such as turkey
Aim of this study was to evaluate the application of these methods, combined with chemometric str... more Aim of this study was to evaluate the application of these methods, combined with chemometric strategies, as non-destructive techniques to evaluate the light induced oxidation in cheese. Semi hard cheese (Edam cheese) was cut in slices with 1 cm thickness and wrapped with clear cling polyethylene film. Samples were stored in a refrigerated industrial display cabinet equipped with fluorescent lights. The light-induced oxidation of samples, stored in the light and in the dark, was monitored by UV-Vis (200-780 nm), FT-NIR (12,500-3,900 cm-1), FT-IR (4,000-700 cm-1) and fluorescence spectroscopy. The overall results have shown that spectroscopic methods are very sensitive to measure the development of light-induced oxidation in cheese products. In particular UV-VIS and fluorescence spectroscopy detected riboflavin decay that appears to be the most light absorbing constituent of cheese
A procedure was developed for the evaluation of heat exchangers for pasteurization treatments usi... more A procedure was developed for the evaluation of heat exchangers for pasteurization treatments using a model solution (10% sucrose; pH = 1.15). This procedure allows the indirect prediction of the thermal damage that will undergo (expressed as the degree of denaturation of single soluble whey proteins or as the percentage of soluble whey proteins with respect to total proteins - SWP% when treated in a continuous flow heat exchanger, whose time-temperature and flow velocity profiles are unknown, but whose holding temperature is known. Heat treatments were performed on an indirect heat exchanger at the laboratory level. A relationship (r(2) > 0.998) between the Co values For sucrose hydrolysis and the Co of each whey protein denaturation and two relationships (for temperatures between 80 and 90 degrees C and for temperature of 75 degrees C) between SWP% and residual sucrose (r(2)=0.853 and r(2)=0.889) were found. These equations allow, after treating the model solution in a heat exchanger, to predict, from residual sucrose, the thermal damage of milk treated in the same operative conditions. Graphs are presented that. allow the degree of whey protein denaturation to be determined from the percentage of hydrolysis of the sucrose solution
Thermal damage of raw milk was evaluated during pasteurization treatments performed in a laborato... more Thermal damage of raw milk was evaluated during pasteurization treatments performed in a laboratory plant that allowed well defined thermal profiles to be established. The thermal damage of the different treatments, carried out at temperatures between 70 degrees and 90 degrees C and for holding times between 12.2 s and 178.6 s, was expressed as soluble whey proteins, as extent of denaturation of each whey protein and as the ratio between the sum of the peak areas of the most thermal sensitive whey proteins (immunoglobulin 1 and 3 + bovine serum albumin) and the total amount of beta-lactoglobulin A and B. Whey protein denaturation kinetics were evaluated obtaining the following activation energy (Ea) (kJ mol(-1)) and Z (degrees C) values: Ig3 Ea = 351, Z = 6.79; BSA Ea = 193, Z = 12.35; beta-LGB Ea = 286, Z = 8.33; beta-LGA Ea = 224, Z = 10.64; alpha-LA Ea = 132, Z = 18.06. On the basis of Z values, the Co parameter was calculated. This allowed the different heat treatments to be compared in terms of loss of thermolabile constituents
In order to face high levels of meat wastage, occurring especially at the distribution and consum... more In order to face high levels of meat wastage, occurring especially at the distribution and consumption stages, food industry envisions new shelf life extension strategies, together with reliable, non-destructive and fast methodologies for product decay monitoring. Therefore, the aim of this work was to assess the reliability of NIR spectroscopy in discriminating storage times of meat packed in low-oxygen systems, recognised as case-ready methods for the shelf life extension of red meat. To the aim, 48 beef meat slices, distributed in 24 trays wrapped in stretched PVC, were individually inserted inside barrier master bags containing O 2 scavengers and low-O 2 modified atmosphere (MA). Each master bag was stored in darkness at 0±1 °C for different times (6, 8, 13 and 15 days). After master bag opening, trays were displayed at 4 ± 2°C under light exposure up to 48 h. Wrapped beef slices were analysed by a fibre optic connected to a FT-NIR spectrometer (MPA, Bruker Optics) immediately after master bag opening and during display life. The obtained dataset (288 spectra), after spectral pre-treatments, was subjected to PCA and LDA by means of MatLab 2016a and V-PARVUS. PCA permitted to distinguish fresh meat from samples exposed to low-O 2 MA, no matter the time spent in the master bags. Moreover, the explorative approach unearthed differences ascribable to anoxic environment storage. Thus, after variable selection by SELECT algorithm, LDA was applied in order to classify samples according to storage times in master bags. Correct classification rates in prediction higher than 87.5% were obtained when considering two classes (1= 6 and 8 days; 2= 13 and 15 days). Concerning meat display under light, LDA classification models were separately calculated for the two considered classes of anoxic storage time, showing global correct classification rates in calibration, cross-validation and prediction higher than 81%, 72% and 68%, respectively. In conclusion, the use of FT-NIR spectroscopy looks promising to estimate simultaneously the anoxic storage time and the deterioration of meat quality attributes throughout display life, thus providing the food industry with an effective packaging system together with a reliable monitoring approach intended for meat wastage reduction.
Foods
Industry 4.0 has prompted a reorganisation of the control systems in food industries to optimise ... more Industry 4.0 has prompted a reorganisation of the control systems in food industries to optimise production while guaranteeing safer food [...]
Foods, 2021
The performance of two innovative packaging materials was investigated on two Sardinian extra-vir... more The performance of two innovative packaging materials was investigated on two Sardinian extra-virgin olive oils (Nera di Gonnos and Bosana). In particular, a transparent plastic film loaded with a UV-blocker (packaging B) and a metallized material (packaging C) were compared each other and to brown-amber glass (packaging A). During accelerated shelf-life tests at 40 and 60 °C, the evolution of quality parameters (i.e., acidity, peroxide value, K270, and phenolic content) was monitored, together with the aromatic fingerprint evaluated by electronic nose. Packaging B resulted in the best-performing material in protecting oil from oxidation, due to its lower oxygen transmission rate (0.1 ± 0.02 cm3/m2 24 h) compared to packaging C (0.23 ± 0.04 cm3/m2 24 h). At the end of storage, phenolic reduction was on average 25% for packaging B and 58% for packaging C, and the aromatic fingerprint was better preserved in packaging B. In addition, other factors such as the sanitary status of the ol...
Italian Journal of Food Science, 1990
A conference abstract from NIRItalia online 2021 in English.
A conference abstract from NIRItalia online 2021 in English and Italian.<br>
A conference abstract from NIRItalia online 2021 in English and Italian.
en sciences et technologies pour l'environnement et l'agriculture.
A preliminary study was carried out to test the possibility of using uracil as a hygienic quality... more A preliminary study was carried out to test the possibility of using uracil as a hygienic quality index for egg products, by comparing it with the legal European indices. Whole egg products prepared at the laboratory scale from eggs with different hygienic quality, as well as industrial egg samples were analyzed. Pasteurization caused a reduction of succinic acid levels, while uracil, lactic and 3-hydroxybutyric acids were not affected. Egg products obtained from sound shell eggs and stored at 4°C for up to 28 days had satisfactory hygienic quality and uracil was not detectable; uracil was detectable in samples made with contaminated raw material. Almost 50% of the industrial samples had detectable uracil values, while only 16% of them exceeded the legal limits using lactic and succinic acids. Preliminary studies proved that uracil, outstanding for its thermostability and high sensitivity, could be a reliable index for evaluating the hygienic quality of the raw material used in manu...
Retailed-manufactured ice-cream samples formulated with 8% fat (milk cream) were produced in trip... more Retailed-manufactured ice-cream samples formulated with 8% fat (milk cream) were produced in triplicate in a batch freezer, either with and without mix homogenization (16MPa) and aging (24h). For comparison, 8% vegetable fat (coconut oil) - based ice cream samples were also produced in triplicate using both aged and non aged homogenized mixes. Fat globule particle size distribution and the kinetics of protein desorption during mix aging were investigated together with ice-cream overrun, firmness, free fat and melting properties. Mix aging did not affect the level of adsorbed protein and the physical characteristics of cream-based ice cream when homogenization was not applied, as traditionally done by ice-cream artisan producers. On the contrary, aging of both cream or coconut oil homogenized formulations caused protein desorption, and ice-cream free-fat reduction and melting rate increase. The level of adsorbed proteins per unit fat globule surface was almost double when vegetable fat was used in homogenized mixes. However, those proteins were quickly desorbed during mix aging. The protein desorption phenomenum was quite less evident in cream-based formulations. No significant effect of mix aging and homogenization were observed on ice cream overrun and firmness
Food Control, 2021
Abstract The effect of physicochemical factors and use of skim milk powder on milk rennet-coagula... more Abstract The effect of physicochemical factors and use of skim milk powder on milk rennet-coagulation was investigated combining near infrared (NIR) spectroscopic monitoring and Multivariate Curve Resolution - Alternating Least Squares (MCR-ALS). Coagulum formation has been studied by reference approaches (Formagraph and fundamental rheology) and with NIR spectroscopy on unaltered reconstituted milk samples, pasteurized samples, samples with calcium chloride addition and samples of reconstituted milk mixed with fresh milk. The MCR-ALS models successfully described the process evolution, explaining more than 99.9% of variance. The MCR-ALS profiles revealed to be significantly directly correlated with Formagraph and rheological data (p 0.05) of the CaCl2 concentration level added and the heat treatment applied. The MCR-ALS models calculated for the coagulation trials of pasteurized skimmed milk mixed with reconstituted milk samples highlighted shorter coagulation times with the increasing of reconstituted milk amount (from 4.3-6.6 min to 2–5 min). Profiles extracted from MCR-ALS models developed for a wide range of coagulation conditions proved to be suitable non-destructive, non-invasive and on-line tools to evaluate the rennet-induced coagulation of reconstituted milks.
Journal of Dairy Science, 1989
Effects of UF on clotting kinetics, curd hardening, and whey syneresis of raw and pasteurized mil... more Effects of UF on clotting kinetics, curd hardening, and whey syneresis of raw and pasteurized milk were studied. Milk was subjected to thermal and mechanical stresses similar to those occurring in a UF plant. To isolate the effects of milk recirculation from those due to protein ...
Journal of Dairy Science, 1989
Abstract The aim of this research was to study the clotting kinetics, curd hardening, and whey sy... more Abstract The aim of this research was to study the clotting kinetics, curd hardening, and whey syneresis of milk concentrated by UF. Experiments were conducted on raw, pasteurized, and UHT-treated milks to verify whether the depression of coagulation characteristics caused by heat treatments of milk could be reversed by the increase in protein concentration. Data demonstrate that rennin action on milk strongly depends on the severity of heat treatment and that curd consistency is influenced both by heat treatment and protein concentration. Ultrafiltration modifies the viscoelastic behavior of curd, resulting in a marked increase in the viscous component at increasing protein concentration. Syneresis decreases as protein concentration increases and is strongly affected by pasteurization and UHT treatment.
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Papers by Ernestina Casiraghi