Fiore Sardo (FS), a traditional Italian cheese, is present in the market as a heterogeneous variety of products. The use of heat-treated (HT) milk is forbidden by the official production protocol, but no official analytical method able to detect heat application is yet available. Here, a combined magnetic resonance imaging (MRI) relaxometry and image analysis approach to recognize FS made from raw milk is presented. Artisanal FS cheeses were produced from raw milk (RC) by five shepherds in accordance with the official protocol. They were compared to HT-milk counterparts (HTC). Additionally, industrially manufactured commercial FS cheeses (I) were also purchased and compared to RC and HTC. Relaxometry data of FS indicated the presence of two water populations; the ratio of characteristic relaxation time constant T₂ and area fraction (Score, Ṩ) of the fastest relaxing population was used to compare RC, HTC and I samples. RC from HTC were successfully discriminated, the latter exhibiting lower Ṩ (enhanced protein hydration). I cheeses exhibited the lowest Ṩ values, sometimes comparable to HTC. Since visual appearance of RC and HTC is appreciably different, an image analysis deep learning approach using MRI and photographic pictures was adopted to discriminate the two productions, with promising percentages (>93%).

The aim of this work was to test native microbial strains and fruits for brewing, with a multidisciplinary approach for a sustainable production linked to the territory. Pediococcus acidilactici B5 and Hanseniaspora uvarum L2 strains were isolated from apricot Bisucciu fruits, a Sardinian local variety (Prunus armeniaca L.), and P. acidilactici B5 was used to ferment a sterile apricot Bisucciu puree, which was then added to a malt wort. The H. uvarum L2 strain and the industrial yeast Saccharomyces cerevisiae US-05 were used sequentially to ferment a portion of this wort (M2); a control was carried out with an industrial yeast, S. cerevisiae T-58 (T58). Beer standard quality parameters were studied and a sensorial analysis performed in the beers obtained from the two fermentations. Intermediate and end molecular products were characterized by proton Nuclear Magnetic Resonance (¹H NMR) for glucidic, organic acids and amino acids and by Gas Chromatography–Mass Spectrometry (SPME/GC/MS) for volatile profiles. M2 and T58 samples showed differences in color, foam stability and in the carbohydrates, acids and amino acids profiles. The highest concentrations of ethyl acetate were found in M2, whereas a high concentration of 3-methylbutan-1-ol characterized T58. Sensory analysis highlighted differences in flavor, astringency and balance between the two beers studied.

This study presents an extensive investigation on the effect of pasteurization on raw whole ewe milk. Milk samples have been analyzed, throughout lactation (from February to July), by time-domain nuclear magnetic resonance (TD-NMR), collecting the characteristic TD-NMR relaxation parameters, proton longitudinal and transverse relaxation times (¹H T₁ and T₂). Collected data aim at integrating previous NMR works, mainly focusing on dairy model systems (casein and whey proteins solutions and gels, reconstituted skim milk) and cheese, with specific reference to the effect of heat treatments. Whole ewe milk, from a single flock (Sarda sheep breed), was daily analyzed both as untreated (raw) and heat treated with a laboratory-scaled high-temperature, short-time treatment (72°C for 15 and 20 s). Moreover, molecular dynamics in milk were investigated by TD-NMR in different periods of lactation for the first time. As a consequence of high-temperature short-time treatment, ¹H T₁ and T₂ consistently shifted to lower values with respect to raw counterparts. Statistical analysis indicated a significant decrease of T₂ in treated samples, to an extent dependent on the heat treatment duration. A subset of dedicated experiments demonstrated that the observed T₂ shift is largely ascribable to protein molecular rearrangements and, to a lesser extent, to the interaction of fat globules with proteins or other nonfat components (or both). In light of the crucial importance of detecting the application of a heat treatment to milk, the results reported here suggest TD-NMR relaxation parameters were able to describe heat-induced changes in molecular dynamics and interactions of milk components in a water-rich environment. The use of TD-NMR can be considered a potential suitable technique for quality control and assurance practices in the dairy industry. Upon statistical validation of methods, the application of TD-NMR in the dairy industry would take advantage of its low cost, reliability, and robustness.