Leaf senescence is the last stage of development of an organ and is aimed to its ordered disassembly and nutrient reallocation. Whereas chlorophyll gradually degrades during senescence in leaves, mitochondria need to maintain active to sustain the energy demands of senescing cells. Here we analysed the motility and morphology of mitochondria in different stages of senescence in leaves of grapevine (Vitis vinifera), by stably expressing a GFP (green fluorescent protein) reporter targeted to these organelles. Results show that mitochondria were less dynamic and markedly changed morphology during senescence, passing from the elongated, branched structures found in mature leaves to enlarged and sparse organelles in senescent leaves. Progression of senescence in leaves was not synchronous, since changes in mitochondria from stomata were delayed. Mitochondrial morphology was also analysed in grapevine cell cultures. Mitochondria from cells at the end of their growth curve resembled those from senescing leaves, suggesting that cell cultures might represent a useful model system for senescence. Additionally, senescence-associated mitochondrial changes were observed in plants treated with high concentrations of cytokinins. Overall, morphology and dynamics of mitochondria might represent a reliable senescence marker for plant cells.

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Purpose Volatile flavor plays a main role in defining the fruit quality by consumers. Bruising leads often to dark spots on fruits and its amount could highly affect product quality. This paper aims to study the effect of bruising on the volatilome released by pears by using proton transfer reaction – mass spectrometry (PTR-MS). Design/methodology/approach Fingerprints of non-bruised and bruised pear samples were collected through PTR-MS for 28 days, and discriminant analysis was used to discriminate the fruit products. The CIELAB color changes were also measured during the entire ripening period. Findings Bruised pears released a higher intensity of volatile organic compounds (VOCs) compared to non-bruised pears (p16days = 0.049, p22days = 0.012, p28days = 0.006). In particular, the release of m/z 45 and m/z 47 were significantly (pm/z 45 = 0.076, pm/z 47 = 0.095.) higher in bruised samples, suggesting that the bruising event accelerated the natural ripening process. CIELAB color coordinates were also recorded. The coordinate a* showed a linear increase during the whole 28 days because of the loss of the green component. The CIELAB ΔE* was higher in the bruised pears than the non-bruised pears (p = 0.022). Originality/value Bruising can affect food quality and taste. Bruise susceptibility has been largely studied on apples, tomatoes and peaches, but rarely on pears. Very little is known about the effect of bruising on the volatilome of pears. Moreover, bruising research usually involved the study of physical properties; on the contrary, PTR-MS, applied to bruising research, has never been used before. Besides the analysis of volatilome, the changes in color were also recorded for the whole 28 days of analysis. The proposed method could be applied for the monitoring of pears quality in the food industry.

The present study aims to demonstrate the potential use of short-wave near infrared spectroscopy for the quality control of raw cow milk samples, collected from high mountain areas. The sampling plan comprised three farms, all located within the same Alpine region (South Tyrol, Italy), but located at different altitudes (1900 m, 1050 m and 950 m a.s.l). Each farm used a similar extensive grassland-based farming system. For comparison, raw milk samples were also collected from a farm located in the valley (Milan, Italy), at 200 m a.s.l. and subjected to an intensive farming system. From each location, the samples were collected 10 times within one month of production. All the milk samples were analysed by diffuse trans-reflectance in the wavelength range from 850 to 1350 nm. Principal component analysis of the spectra revealed that the short-wave near infrared bands, respectively, 847, 1084, and 1095 nm, were the most important to distinguish milk between farms. The signal intensities of these wavelengths were used to build a multivariate control chart based on the Hotelling T2 statistic. The results showed that short-wave near infrared spectroscopy can be successfully used to monitor milk products in a fast, simple and on-line way.

: Food integrity could be jeopardizesby different type of food frauds. The concept of food integrity is composed by three pillars: (i) food quality, i.e. number of features, objective and subjective, of food that are acceptable to consumers and meet their expectations; (ii) food authenticity, namely the ability to follow the movement of a feed or food through specified stage(s) of production, processing, and distribution; and (iii) food safety, which is the probability of not becoming ill after consuming a food. Food fraud, i.e., modifications of food characteristics and/or ingredients can affect the quality, authenticity and safety of food products. Moreover, these practice can affect consumers’ expectation and trust. In this review, applications of vibrational spectroscopy(NIR and FT-IR) and proton transfer reaction-mass spectrometry(PTR-MS) for food quality, authenticity and safety analysis will be discussed. Examples of how vibrational spectroscopy and proton transfer reaction – mass spectrometry applied to food integrity analysis will be given with regards of oils, milk and dairy products, and coffee.