Search results

This study aims to evaluate the effect of grape seed extract on the thermal oxidation of soybean oil.

Four treatments were used: soybean oil (SO), butylhydroxytoluene (BHT), antioxidant at concentration of 100 mg/kg in soybean oil (BHTSO), grape seed extract at a concentration of 100 mg/kg in soybean oil (Extract), and mixture at a concentration of 50 mg/kg of grape seed extract (Mixture) and 50 mg/kg of BHT in soybean oil subjected to 180°C for 20 h. The total phenolic compounds were quantified by spectrophotometry using the Folin-Ciocalteu reagent. The antioxidant activity was evaluated by the ABTS^•+, DPPH^• and FRAP acid systems. The fatty acid composition and phytosterols were determined by gas chromatography (GC) and tocopherols were determined by high-performance liquid chromatography.

Among the treatments studied, the Extract and the Mixture presented lower losses of total phenolic compounds, DPPH^• and FRAP, while BHTSO had an opposite effect. After 10 h of heating, the Mixture and the Extract were more effective in reducing the formation decomposition products, measured by the amount of total polar compounds. The Mixture resulted in higher retention of essential fatty acids at the end of heating. The Extract and Mixture showed higher retention rates of total tocopherols and the Mixture resulted in 338.71 mg/100 g (P ≤ 0.05) of total phytosterol after 20 h of heating.

Oils undergoing the heating process suffer major changes, requiring the addition of antioxidant compounds. As a result of the questioning on the use of chemical additives, research on natural antioxidants, as substitute to the synthetic ones, is increasing. Among the natural compounds with high antioxidant potential, the grape wastes such as its seeds are highlighted. Studies using grape seed extract are scarce.

This paper aimed to evaluate sensory acceptability of salad dressing formulated with different quantities of oregano essential oil (OEO) and salt as a starting point for the use of the spice as a natural preservative in food.

Sensory assessment of salad dressing with OEO was evaluated in relation to the following attributes: appearance, aroma, consistence, flavour and overall acceptability. Five formulations were developed with variation in the levels of OEO and sodium chloride through a 22 factorial design with a central point. A nine-point hedonic scale was used, besides purchase intent by a structured five-point scale.

There was no significant difference in the acceptance of the samples. Cluster analysis showed that formulation with intermediate quantities of salt and OEO was preferred by the consumers. OEO salad dressings with low salt content, regardless of OEO amount, presented higher intention to purchase.

Due to an increasing interest in the use of natural preservatives to replace chemical additives, this study provided a starting point for further investigations concerning sensory acceptability of OEO in food.

Finding the balance between pleasant flavour and significant reduction of the use of salt in foods for dietary reasons is a complex challenge. Furthermore, studies need to be performed concerning interaction between amounts of essential oils and salt.

This study provides insights that suggest a promising usage of OEO in food.

This paper aims to evaluate the consumer acceptance of Bordô and Isabel wines from innovative winemaking in order to increase red wine consumption by consumers to obtain nutritional benefits.

All wines were produced by a standard procedure of vinification. Pre‐drying treatment aimed at drying the grapes up to 22°Brix and static pomace wines presented the constant contact between the must and pomace. Sensory acceptance was carried out by 80 consumers who evaluated eight samples (six experimental wines and two commercial wines) concerning the attributes: appearance, aroma, body, flavor and overall acceptance.

Experimental wines presented higher acceptance when compared to commercial wines and cluster analysis shows the splitting of consumer preferences, highlighting the higher acceptance of traditional Bordô wine and static pomace samples in all sensory attributes. Pre‐drying process enhances the concentration of coloured compounds, to highlight the appearance acceptance of these samples.

Although this paper has limited the consumer acceptance of red table wines, the innovative treatments will be applied in Vitis vinifera red wines.

The wide acceptance of static pomace and pre‐drying wines has promoted further information about innovative winemaking that can be applied in Brazilian and worldwide wineries.

The innovative treatments can change sensorial features of wines and therefore influence the choice of consumers as well as enhancing the nutritional benefits of red wines.

The pre‐drying and static pomace winemaking are the novelty of this study and the wide acceptance of the sensory attributes concerning these treatments indicates the potential for application in wineries.

This paper aims to evaluate in vitro antibacterial activity of oregano essential oil against foodborne pathogens as a starting point for the use of spice as a natural preservative in food.

Disc and well‐diffusion assays were performed to investigate antibacterial activity of oregano essential oil against six bacteria strains: Bacillus cereus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Salmonella Typhimurium. Three concentrations of oregano essential oil were employed: 1.0 percent, 2.0 percent and 5.0 percent. Bacterial growth inhibition was determinate as the diameter of the inhibition zones.

Oregano essential oil showed antibacterial activity against spoilage microorganisms, at different concentrations, except for P. aeruginosa. There was a significant difference between methodologies only for the microorganism S. aureus. The results provided evidence of the existence of significant differences among the concentrations of oregano essential oil for each microorganism evaluated.

Although the research for this paper involved only oregano essential oil, it provided a starting‐point for further investigations concerning spices as natural preservatives for food systems.

Disc and well‐assays were found to be simple and reproducible practical methods. Other spices, their essential oil and extracts might be researched against other micro‐organisms. Furthermore, in situ studies need to be performed to evaluate possible interactions between essential oils and compounds naturally present in food against microbial strains.

The imminent adoption of measures to reduce the use of additives in foods and the reduction on using such compounds.

This study provides insights that suggest a promising exploratory development of food natural preservative against spoilage microorganisms in food systems by the use of oregano essential oil.