Syrah grape skin valorisation using ultrasound-assisted extraction: Phenolic compounds recovery,antioxidant capacity and phenolic profile

The influence of ultrasound power (1000–3000 W/L), citric acid concentration (0–3%) and solid:liquid ratio (1:5–1:15) on the phenolic compounds recovery and antioxidant capacity of Syrah grape skin extracts were evaluated. Total phenolic compounds varied from 6485 to 11732 mg gallic acid/100 g and monomeric anthocyanin content from 453 to 685 mg malvidin-3-glucoside/100 g. The antioxidant capacity measured by ORAC and ABTS methods ranged from 230 to 516 μmol Trolox/g and from 442 to 939 μmol Trolox/g, respectively. The most suitable conditions chosen for extraction, within the studied ranges, were 3000 W/L of power, 2.5% citric acid and solid:liquid ratio of 1:15. The extraction yield was satisfactory, with a recovery of 59% of the quantified phenolic compounds, with only 3 min of processing. Ultrasound was considered a suitable method as compared to the conventional extraction, improving the extraction of phenolic acids and facilitating their release.     

Plant oil bioconversion into increase biological activity through lipases derived from wastes

The aim of this study was to show that abundant and inexpensive plant oils can be biotransformed to increase biological activity (antioxidant, antimicrobial and cytotoxicity) through hydrolysis reaction catalysed by lipases. We tested homemade and commercial lipases through the biotransformation of nine different plant oils in forty different combinations. First, the chemical composition of the samples was investigated. Thereafter, biological tests were conducted to assess the antioxidant and antimicrobial activity of the sampled biotransformation products, as well as analyzed their influence on the viability of healthy and cancer cells. Summarising, sunflower, corn and olive oils modified by orange waste-obtained lipases presented the most promising results, reaching up to 90% of antioxidant activity increase and significant growth inhibition of bacteria colonies belonging to genera Escherichia, Listeria, Staphylococcus, Pseudomonas and Salmonella. In addition, those compounds affected human oral squamous carcinoma cells. The bioconversion of plant oils through lipases improves their biological properties and might be an option for biotechnological application.     

Physical characteristics of extrudates from corn flour and dehulled carioca bean flour blend

Extruded products were prepared from a corn flour and dehulled carioca bean (Phaseolus vulgaris, L.) flour blend using a single-screw extruder. A central composite rotate design was used to evaluate the effects of extrusion process variables: screw speed (318.9–392.9 rpm), feed moisture (10.9–21.0 g/100 g) and bean flour level (4.8–55.2 g/100 g) on the specific mechanical energy (SME), sectional expansion index (SEI), longitudinal expansion index (LEI), volumetric expansion index (VEI) and density (D) of the extrudates. The instrumental texture was also analyzed. The independent variables had significant effects on the physical properties (SEI, VEI and density) of extrudates, with the exception of SME and LEI. SEI increased with increasing screw speed, but a higher moisture and bean flour content resulted in decreasing SEI and VEI. The increase of moisture and bean flour increased the density of extrudates. According to texture analysis, some treatments with 30 and 45 g/100 g bean flour did not show significant differences when compared to commercial brand snacks. However, when combined with higher moisture content (≥19 g/100 g) and lower screw speed (≤333 rpm), the results of the expanded product were not satisfactory.     

Analysis of food dyes E 110, E 111, and E 124 in fish samples by ion pair partition HPLC

Zusammenfassung Das isomere Farbstoffpaar E 110 und E 111 kann nach Ionenpaarbildung auf UmkehrPhasen-Säulen in HPLC gut getrennt werden. Das in Deutschland nicht mehr zugelassene Isomere E 111 kann auf diese Weise in Farbstoff- und Lebensmittelproben bestimmt werden.Die Analyse von E 110, E 111 und E 124 in Seelachsproben wird beschrieben.

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Analysis of food dyes E 110, E 111, and E 124 in fish samples by ion pair partition HPLC

Summary The isomeric food dyes E 110 and E 111 can be separated by ion pair partition HPLC on reversed-phase columns. The isomer E 111 - no longer permitted in Germany - can thus be determined in dye and food samples. The determination of E 110, E 111, and E 124 in fish samples (canned saithe) is described.

     

The dependence of crude papain yields on different collection (‘tapping’) procedures for papaya latex

The yields of fresh papaya latex, dry latex (crude papain) and proteolytic activity were studied with respect to fruit age (1.5–3 months); sex of the tree (those which produce fruit: female and hermaphrodite); time (5:30 a.m.-2:00 p.m.) of latex collection; pattern and frequency of fruit incisions. The yields from 250 randomly selected trees (750 fruits) were investigated under these different conditions. Yields of fresh latex are frequently unreliable guides to yields of proteolytic activity. In contrast to the literature recommendations, the yields of crude papain from female and hermaphrodite trees and during different periods of the day were similar. The proteolytic activity differs significantly with time of collection only with hermaphrodite trees. The proteolytic activity of hermaphrodite crude papain is usually less than that from females (under some conditions only 60% of that from females). Yields of crude papain were higher in older fruits (2.5–3 months) from both sexes. The proteolytic activity of the crude papain was highest in the younger fruits (1.5–2 months) from female trees (30% higher than from older fruits); these activity differences with age were not significant with hermaphrodite trees. No significant differences in crude papain yields were encountered using three or six incisions per fruit at weekly intervals. The optimum procedure is to tap 2.5–3-month-old fruit of both sexes with three incisions between dawn and the start of rains in early afternoon, at about 4-day intervals.     

The storage and drying characteristics of papaya (Carica papaya L.) latex

A range of latex storage and air drying conditions were studied with regard to the proteolytic activity of the dried latex (‘crude papain’). The optimum drying temperature is between 50–55°C, activity losses on drying can be restricted to about 7% under these conditions. The activity of crude papain is the same if it is derived either from exuded latex or from that portion (about 20% of latex yield) which coagulates on the fruit surface on tapping. Latex storage at tropical ambient for 2–24 h prior to drying (with or without exposure to sunlight) causes maximum losses of about 20% in the proteolytic activity of the crude papain. Sodium chloride addition has an anti-coagulating effect on latex and accelerates the later stages of drying. Contrary to earlier reports, this causes a decreased activity in the product, which may be related to changes in latex pH. Addition of EDTA or sodium bisulphite, singly or in combination, protects the latex activity (increases of 20–25% relative to controls).     

Changes in the non-structural carbohydrates associated with the field drying of oat forage

Two trials were conducted to determine the sugars, fructans and starch in oat plants (Avena sativa L) and the changes occurring in these carbohydrate fractions during field drying in the haymaking process. The composition of oat herbage in non-structural carbohydrates varied markedly between years; the contents of sugars, fractals and starch in both leaf blade and non-leaf blade materials being nether in 1990–1991 than in 1991–1992. Field drying produced a significant decrease (P < 0.05) in the amount of soluble carbohydrates. For the whole aerial plant parts, the decline in the fructans concentration ranged between 42.8 and 38.2% and that of sugars between 16.5 and 5.8%. The total losses of sugars and fractions in hay, expressed as losses of dry matter, ranged from 88 to 63 g kg^?1 depending on the year.