Despite the increasing interest in organic products, knowledge about how different levels of fertilization affect nutritionally relevant components is still limited. The concentration of polyphenols and the activity of polyphenoloxidase (PPO), together with the content in ascorbic acid, citric acid, and alpha- and gamma-tocopherol, were assayed in conventional and organic peach (Prunus persica L., cv. Regina bianca) and pear (Pyrus communis L., cv. Williams). 2-Thiobarbituric acid reactive substances and the tocopherolquinone/alpha-tocopherol ratio were used as markers of oxidative damage in fruits. A parallel increase in polyphenol content and PPO activity of organic peach and pear as compared with the corresponding conventional samples was found. Ascorbic and citric acids were higher in organic than conventional peaches, whereas alpha-tocopherol was increased in organic pear. The concentration of oxidation products in organic samples of both fruits was comparable to that of the corresponding conventional ones. These data provide evidence that an improvement in the antioxidant defense system of the plant occurred as a consequence of the organic cultivation practice. This is likely to exert protection against damage of fruit when grown in the absence of pesticides.

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Milk is generally very rich in nutrients and this may lead it to be an ideal growth environment for many microorganisms, including pathogens, so effective measurements aiming to ensure total microbiological safety of milk and minimize the risk to human health are needed. Milk heat treatments are the most common practices carried out to inhibit the microbial growth; therefore it is necessary to have analytical procedures that are more and more up-to-date and capable of detecting the effectiveness of the heat treatments. Most of the reference and official methods to assess heat treatment in milk are based on the evaluation of the modifications of some milk components following the thermal process, such as the determination of enzyme activities (alkaline phosphatase and lactoperoxidase), whey proteins, Maillard reaction compounds (generally furosine), and lactulose. Besides the most common techniques (liquid and gas chromatography, capillary electrophoresis, or spectroscopy) used for the detection of single thermal indicators, new approaches, such as chemometric studies or more recent techniques, including size-exclusion chromatography with online electrospray mass spectrometry or stable isotope ratio mass spectrometry, are discussed in this review in order to evaluate heat treatment in milk.

Different technologically treated Italian milks (whole and semi-skimmed ultra-high temperature (UHT), pasteurized and microfiltered milk), collected from 2009 to 2012, were evaluated for nutritional and technological properties. No significant differences in calcium and sodium were detected (p > 0.05), while significant differences were observed concerning phosphorus content, between whole and semi-skimmed milk, and lactose content, between pasteurized and UHT milk (p < 0.05). In UHT milk, lactose isomerization occurred, and lactulose (from 8.6 to 104.0 mg/100 g) was detected. No significant differences (p > 0.05) were detected for choline, a functional molecule, between whole (11.3–14.6 mg/100 g) and semi-skimmed milk (11.1–14.7 mg/100 g), but there were significant differences (p < 0.05) in processing milk (UHT vs. pasteurized milk and UHT vs. microfiltered milk). Among the unsaponifiable compounds, only 13 cis retinol and trans retinol showed differences in technologically treated milk (pasteurized vs. UHT milk and microfiltered vs. UHT milk; p < 0.05). In this research, the greater was the “severity” of milk treatment, the higher was the percent ratio 13 cis/trans retinol (DRI, degree of retinol isomerization). The degree of antioxidant protection parameter (DAP), useful to estimate the potential oxidative stability of fat in foods, was significantly different between whole and semi-skimmed milk (p < 0.05). Finally, the evaluation of color measurement of whole milk showed a good correlation between beta carotene and b* (r = 0.854) and between lactulose and a* (r = 0.862).

Chemical composition and content in polyphenols, phytic acid, and dietary fiber of whole cooked common bean (Phaseolus vulgaris L.) and faba bean (Vicia faba L.) and of soluble and insoluble fractions separated from them were determined. Simultaneous determination of Cu, Fe, and protein bioavailability in the small intestine of rat was carried out in single-dose, short-term (1 h) experiments. After cooking, about 80% of seed components (on a weight basis) of either legume was recovered in the precipitate (insoluble fraction) after extraction with water. Protein, lipid, starch, dietary fiber, and polyphenols underwent the most severe insolubilization, together with more than 70% of total Cu and Fe. Cu, Fe, and protein bioavailability showed a similar trend (i.e., the lower the protein, the lower the Cu and Fe availability). Availability of proteins, Cu, and Fe in the insoluble fractions were the lowest, but Cu bioavailability was higher than that of Fe in all fractions. The results provide evidence that the heat-induced insolubilization process adversely affects not only protein but also Cu and Fe bioavailability from legumes and that polyphenols are likely to be a major inhibitor on absorption.