Foliar Application of CaCO3-Rich Industrial Residues on 'Shiraz' Vines Improves the Composition of Phenolic Compounds in Grapes and Aged Wine.

The quality of wine grapes and wine depends on their content of phenolic compounds. Under commercial conditions, the phenolic maturity of grapes is mostly achieved by applying abscisic acid analogues. Some Ca forms represent a cost-effective alternative for these compounds. In this study, 'Shiraz' vines (veraison of 90%) were sprayed with CaCO3-rich residues from the cement industry (4.26 g of Ca per L). Fruit from treated and untreated vines was harvested 45 days after CaCO3 spraying and evaluated for quality. The fruit was vinified, and the obtained wines were bottled and stored in darkness for 15 months at 20 °C. Wines were evaluated for quality after storage. The evaluation of grape and wine quality included the content of phenolic compounds and antioxidant capacity. The treatment with CaCO3 did not affect the ripening rate of grapes. However, the treatment improved the fruit yield as well as the color development, the content of phenolic compounds, and antioxidant capacity of grapes and wine. The treatment favored especially the accumulation of malvidin-3-O-glucoside, pelargonidin-3-O-glucoside, caftaric acid, caffeic acid, trans-cinnamic acid, quercetin, catechin, epicatechin, resveratrol, and the procyanidins B1 and B2. Wine made with treated fruit was of higher quality than that of control fruit.

Effect of cultivar on the content of selected phytochemicals in avocado peels.

The peels of ripe fruit of 'Hass' and 'Hass' type (HT) avocado cultivars were evaluated for phytochemical composition and other attributes. Peels represented from 8.78 to 14.11% of fruit weight. Their color ranged from homogeneous black to black with very small greenish spots. The oil content in the peels was low. Twelve fatty acids were identified in peel oil and the ratio of unsaturated to saturated fatty acids suggested that peel oil might contribute to human health. The phytochemical composition varied significantly with cultivar. However, many HT peels were superior than 'Hass' peel in their content of α-tocopherol, ß-sitosterol, perseitol, and cyanidin-3-glucoside, which was up to 211.67, 45.92, 337.17, and 519.27% higher in HT peels, respectively. The content of some phenolic compounds, especially procyanidin B2 and epicatechin, was significantly lower in 'Hass' than in many HT peels. Few HT peels showed a higher content of carotenoids and chlorophyll than 'Hass' peels. Lutein was the most abundant carotenoid. Chlorophyll a and b were also abundant in peels and low concentrations of chlorophyll derivatives were observed. Avocado peels are an important source of bioactive compounds, including some carotenoids, acids, sterols, and volemitol, which were observed for the first time.

Metabolomic analysis and physical attributes of ripe fruits from Mexican Creole (Persea americana var. Drymifolia) and 'Hass' avocados.

The physicochemical properties, including nutrient and bioactive compound compositions, in fruit of four creole avocados (CA) from Mexico were determined and compared with those of 'Hass' fruit. 'Hass' pulp and some CA pulps contained similar concentrations of lutein, chlorophyll a, ß-sitosterol and α-tocopherol. CA pulp contained 3.91-9.55% more oil than 'Hass'. Oil from CA pulp contained 10.10-26.79% more oleic acid than 'Hass' pulp. However, CA were small (CA = 81.40-137.15 g, 'Hass' = 188.59 g) and their pulp contents were low (CA = 39.83-84.82 g, 'Hass' = 144.14 g). CA peels were very thin, making these avocado peels edible but prone to mechanical damage. CA peels also contained higher concentrations and greater diversity of anthocyanins and glycosylated quercetin compounds than 'Hass' peels. Some CA were particularly rich in mannoheptulose and perseitol. Consumption of CA, including their peel, might result in higher intakes of some nutrients and bioactive compounds compared with 'Hass' avocados.

Effects of pectin on lipid digestion and possible implications for carotenoid bioavailability during pre-absorptive stages: A review.

Pectin, an abundant polysaccharide in the human diet, has structural characteristics and functional properties that are strongly dependent on the food matrix (e.g., origin, type, cultivar/variety, ripening stage, style and intensity of processing). These polysaccharides have a strong effect on lipid digestion, which is required for the liberation of carotenoids from emulsified lipid droplets in the gastrointestinal content and for the formation of micelles, in which the carotenoids must be incorporated before absorption. Only micellarized carotenoids can be absorbed and subsequently exert protective effects on human health. The alteration of lipolysis by pectin can occur through several mechanisms; however, they have not been linked directly to carotenoid micellarization. This paper provides an overview of the effects of the properties of pectin on the ion concentration in the digestive content, the viscosity of the digestive medium, the properties of the lipid droplet surfaces and lipase activity and analyzes the impact of these events on lipid digestion and subsequent carotenoid micellarization.

Effect of ripening and heat processing on the physicochemical and rheological properties of pepper pectins.

Water-, chelator-, and alkali-soluble pectins were isolated from raw and heat-processed Jalapeño peppers (green and red) and their physiochemical and rheological properties were determined. The yield, tristimulus color, degree of methyl esterification, monosaccharide composition, molecular weights distribution, and protein content depended on ripening and heat processing. The viscosity properties of pectins were independent of ripening. The water-soluble pectin was the most abundant pectin. Pectins from grilled peppers showed the lowest L* values. The alkali-soluble pectin showed the highest protein content. The content of xylose, rhamnose, and mannose in pectins was highly altered by tested factors. The degree of methyl esterification of pectins ranged from 26.8 to 91.6%. The peak Mw of the main fraction of tested pectins was sequentially reduced by ripening and heat processing. Pectins from raw peppers showed the best viscosity properties.

Effect of heat processing on the profile of pigments and antioxidant capacity of green and red jalapeño peppers.

Raw and heat-processed jalapeño peppers (green and red) were evaluated for their pigment profile and antioxidant capacity. Sixty-seven pigments were separated and characterized by HPLC-DAD-MS, including carotenoids (isomers and esters), chlorophylls, and pheophytins. The distinctive characteristics of this pepper genotype were the presence of antheraxanthin monoesters, zeaxanthin monoesters, mutatoxanthin diesters, and a higher content of free capsanthin relative to the mono- and diesterified forms. Chlorophyll a and free all-trans-lutein were the major pigments in raw green peppers, whereas free all-trans-capsanthin was the most abundant pigment in raw red peppers. Twelve compounds were generated by the heat treatments, mainly pheophytins and cis isomers of carotenoids. Heat treatments affected differentially the concentration of individual pigments. Red peppers showed a higher antioxidant capacity than green fruits. Heating caused minor changes in the antioxidant capacity of peppers.

Irreversibility of chilling injury in zucchini squash (Cucurbita pepo L) could be a programmed event long before the visible symptoms are evident.

Zucchini fruits were subjected to 2.5 or 10 degrees C for 16d, followed by transfer to 20 degrees C for 24h in order to evaluate the relationship between ripening pattern, measured as CO(2) evolution and ethylene (C(2)H(4)) production, and metabolic heat production (q). Chilling injury (CI) visible symptoms were evident after 8d at 2.5 degrees C, but none were recorded on fruits kept at 10 degrees C. In fruits held at 10 degrees C, q, C(2)H(4) production, and CO(2) evolution diminished in the course of 16d, whereas in those at 2.5 degrees C CO(2) evolution showed an early burst peaking at 8d. Both C(2)H(4) production and q also showed a burst at 2.5 degrees C but they started at 4 and 8d, respectively, and peaked at 12d. The results showed that irreversibility of chilling injury in zucchini could occur long before the appearance of visible symptoms, although the metabolic activity accompanying the irreversibility process was not noticeable by isothermal calorimetry.