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The aim of this research was to study the relationships between electronic nose (E-nose) pattern, maturity class of peaches assessed at harvest by means of absorption coefficient at 670 nm (μ(a)670) measured in fruit pulp by time-resolved reflectance spectroscopy (TRS), and quality evolution during a 4 week cold storage. 'Spring Belle' peaches were measured for μ(a)670 by TRS, ranked according to decreasing μ(a)670 value, divided into three TRS maturity classes (less (LeM), medium (MeM), and more (MoM) mature), and randomized into 9 samples of 30 fruit each, so that fruits from the whole μ(a)670 range were present in each sample. At harvest and after 1, 2, 3, and 4 weeks of storage at 0 and 4 °C, fruits of each sample were evaluated for firmness, expressible juice, μ(a)670, and ethylene production. LeM and MoM peaches of each sample were analyzed for aroma pattern by a commercial electronic nose and by static HS-GC and for sugar (glucose, fructose, sucrose, and sorbitol) and organic acid (quinic, malic, and citric acids) compositions by HPLC. Principal component analysis (PCA) of electronic nose data emphasized the ability of the E-nose to assess the ripening stage of fruit associated with maturity class, storage time, and storage temperature. The sensors having the highest influence on the pattern were W5S in PC-1, W1S in PC-2, and W2S in PC-3. From linear correlation analysis between PCs and firmness, flavor, and volatile compounds, it was found that PC-1 was related to ethylene production and volatile compounds (mainly acetate esters and ethanol); the highest PC-1 scores were found for fruit belonging to the MoM class after 2 weeks of storage at 4 °C, which showed the rise in ethylene production coupled with the highest total volatile production and sugar and acid composition of ripe peach fruits. PC-2 correlated with hexanal, ethyl acetate, and sugar composition, and PC-3 was mainly related to flavor compounds; both functions significantly changed with cold storage time in different ways according to storage temperature and maturity class.

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Tomato is one of the most widely consumed fresh vegetables in the industrialized world and an important source of healthy constituents of the human diet. Despite the unique flavor characteristics of tomatoes, which make them extremely valuable in cooking, and their recognized beneficial role in the diet, the quality of tomato was traditionally only considered in connection to external appearances. As it happened with other highly requested crops, breeding programs of tomato focused their efforts on developing new varieties with higher yields and stress resistance, with better uniformity in fruit size, brighter color and prolonged shelf life. The downside of these strategies was that organoleptic features and nutritional value were often neglected, with a detrimental effect on commercial tomatoes. Over the last years, there has been an increase in consumers’ demand for tasty and healthy products. This aspect, paired with novel and multidisciplinary approaches to tomato research, allowed both sensory and nutritional qualities to be reconsidered as valuable parameters in breeding. In this review we describe the main chemical constituents of tomato, focusing on the flavor compounds (both volatile and non-volatile compounds) and secondary metabolites. Particular attention is paid to their beneficial effects on human health and their relevance to the overall quality of tomato.

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The aims of the present study were to describe intermuscular differences in meat-quality traits in 15 young-sheep muscles, and to study the associations between meat quality and fibre typing across all (pooled) muscles as well as in previously selected homogeneous contractile–metabolic groups of muscles (slow-oxidative, intermediate and fast-glycolytic muscles). Meat-quality traits (pH, colour, expressed juice, cooking losses, tenderness and sarcomere length) and fibre typing were evaluated after 24 h of slaughter in 15 muscles from five cross-bred young sheep. Across all the studied muscles, intermuscular differences in some meat-quality traits (pH24, a* and expressed juice) seemed to be mainly explained by muscle oxidative activity, while intermuscular variation in other meat-quality traits (L*, b* and Warner–Bratzler shear force) were mainly explained by differences in fibre sizes. Within fast-glycolytic muscles, larger fast-glycolytic fibres and reduced oxidative activity were generally associated with lower ultimate pH, higher L* values, lower a* values and longer sarcomeres. Within intermediate muscles, larger fast-glycolytic fibres and reduced oxidative activity were generally associated with lower ultimate pH, higher L* values, shorter sarcomeres and reduced meat tenderness. Within slow-oxidative muscles, larger fast-glycolytic fibres and reduced oxidative activity were generally associated with lower amounts of expressed juice, lower a* values and reduced meat tenderness. The present study has contributed to a better understanding of the influence of muscle fibre types on intermuscular meat-quality variation, suggesting that although muscle fibre diversity may explain, at least in part, intermuscular differences in meat quality, these associations can also slightly vary among muscle contractile–metabolic groups.