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Phenolic content of strawberry spreads during processing and storage.

This study provides a comprehensive and systematic evaluation of phenolics in strawberry spreads processed according to different industrial procedures and stored under several storage conditions for up to 19 weeks. Total phenolics were determined spectrophotometrically, and individual phenolics were determined by combined liquid chromatography and mass spectrometry: six anthocyanins, four phenolic acids, two flavonols, one flavanol, and one flavone. During storage, the phenolics were modified. The total anthocyanins, vanillic acid, kaempferol, and luteolin decreased, while salicylic and gallic acids increased. Total phenolics, cyanidin 3-(6″-succinyl-glucoside) (here observed for the first time), protocatechuic acid, quercetin, and catechin remained stable. The best phenolic retention was observed in spreads stored at 4 °C. Therefore, the proposed storage process (use of a cold chain) indicates good retention of phenolics in strawberry spreads, which maintain high nutritional and sensorial quality.

LC–MS analysis of phenolic compounds and antioxidant activity of buckwheat at different stages of malting

The impact of malting on the profile of the phenolic compounds and the antioxidant properties of two buckwheat varieties was investigated. The highest relative increases in phenolic compounds were observed for isoorientin, orientin, and isovitexin, which are consequently major inducible phenolic compounds during malting. Only a minor relative increase was observed for the most abundant phenolic compound, rutin. The radical-scavenging activity of buckwheat seeds was evaluated using ABTS and DPPH assays. A considerable increase in total phenolic compounds and higher antioxidant activity were observed after 64h of germination, whereas kilning resulted in decreased total phenolic compounds and antioxidant activity. Higher antioxidant activities for extracts were found for buffered solvents than for pure methanol and water. Changes in the composition of the phenolic compounds and increased antioxidant content were confirmed by several methods, indicating that buckwheat malt can be used as a food rich in antioxidants.

Increasing Top-20 Diversity Through Recommendation Post-processing

This paper presents two different methods for diversifying recommendations that were developed as part of the ESWC2014 chal- lenge. Both methods focus on post-processing recommendations provided by the baseline recommender system and have increased the ILD at the cost of final precision (measured with F@20). The authors feel that this method has potential yet requires further development and testing.

Volatile compounds of freeze-dried sour cherry puree affected by the addition of sugars

ABSTRACT The aim of this work was to determine the influence of the addition (5, 10, or 20 g/100 g) of different sugars (sucrose, maltose, or trehalose) prior to freeze-drying on the key volatile compounds of the sour cherry puree. The key volatile compounds of sour cherries were benzaldehyde, benzyl alcohol, and 2-hexenal. The results obtained for the samples with the addition of sugars were compared to the control sample, the sample without sugar addition. The control sample contained 3.92 mg/kg of benzyl alcohol, 856.61 µg/kg of benzaldehyde, and 15.58 µg/kg of 2-hexenal. Benzaldehyde, the compound described as the typical cherry volatile compound, was determined in the highest amount in the sample with the addition of 10 g/100 g of trehalose (937.51 µg/kg). The highest amount of 2-hexenal was determined in samples with the addition of 10 or 20 g/100 g of trehalose (17.45 and 18.96 µg/kg, respectively). All samples with the sugar addition had lower content of the benzyl alcohol than the control sample. Generally, samples with the addition of sucrose had the lowest amount of examined volatile compounds.

Oxidative stability of n-3-enriched chicken patties under different package-atmosphere conditions

The oxidation processes were studied in chicken patties, enriched with n-3 fatty acids, after 8days of storage at 4°C, under different aerobic conditions, and following heat treatment. Significant effects were seen on lipid and cholesterol oxidation and the sensory qualities for whole flaxseed addition in the chicken feed (i.e., n-3 fatty acid enrichment), and for the different package-atmosphere conditions. For the raw chicken patties, n-3 enrichment increased the colour L(∗) values while, after the heat treatment, there were higher thiobarbituric acid-reactive substances (TBARs) and cholesterol oxidation products (COPs), and the rancidity was more pronounced. In comparison with the low O2 (<0.5%) package-atmosphere condition, O2 enrichment (80%) increased the instrumentally measured colour values, TBARs, total and individual COPs, and the rancidity became pronounced. The most suitable package-atmosphere condition of these raw n-3-enriched chicken patties is a very low O2 atmosphere, with or without an O2 scavenger.

Modelling the Colour of Strawberry Spread During Storage, Including Effects of Technical Variations

Abstract The colour of freshly processed strawberry spread changes relatively rapidly from a bright red to a dull red, which then makes its appearance generally less acceptable for consumers. The colours of strawberry spreads following several processing conditions were measured under different storage conditions. Additional sugar and colorant had only slight effects on the colour decay, while exclusion of oxygen and daylight did not affect this process. The only condition that clearly maintained the freshly processed appearance was storage at 4°C. Hexagonal bottles were filled with the strawberry spreads and their colour was repeatedly measured at the six sides of the bottles, using a Minolta chroma meter. Data were analysed using non-linear indexed regression analysis based on a logistic function for the three colour aspect of a*, b* and L*. This technology allowed the determination of the variation in these data in terms of improved reliability (R2adj, >90%). It also allowed better interpretation of the processes involved. All variations in the data could be attributed to technical variation.

Mechanical Stress Results in Immediate Accumulation of Glucosinolates in Fresh-Cut Cabbage

The intensity of mechanical stress and the temperature significantly affect the levels of individual and total glucosinolates in shredded white cabbage (cv. Galaxy). Mild processing (shredding to 2 mm thickness) at 8°C resulted in the accumulation of glucosinolates (40% increase) in comparison with unshredded cabbage, which was already seen 5 min after the mechanical stress. Severe processing (shredding to 0.5 mm thickness) at 20°C, however, resulted in an initial 50% decrease in glucosinolates. The glucosinolates accumulated in all of the cabbage samples 30 min from processing, resulting in higher levels than in unshredded cabbage, except for the severe processing at 20°C where the increase was not sufficient to compensate for the initial loss. Glucobrassicin and neoglucobrassicin were the major glucosinolates identified in the cabbage samples. Mechanical stress resulted in an increase in the relative proportion of glucobrassicin and in a decrease in neoglucobrassicin.