Javier García-Lomillo

Antioxidant and Antimicrobial Properties of Wine Byproducts and Their Potential Uses in the Food Industry

Wine pomace (WP) is one of the agricultural byproducts that has received most attention from food scientists due to the wide range of interesting compounds that remain after the winemaking process. Different powdered products rich in phenolic compounds, with interesting antioxidant and antimicrobial activities, were obtained from WP by applying processes that are both environmentally friendly and economically affordable for the food industry. The products obtained showed high global antioxidant activities (ABTS assay), successfully delayed the onset of lipid oxidation in the Rancimat test, and showed different antimicrobial properties. Products derived from seed-free WP showed bactericidal effects against total aerobic mesophilic bacteria (TAMB) and lactic acid bacteria (LAB) and inhibited Enterobacteriaceae growth completely. The product derived from whole WP presented bacteriostatic activity against the three microorganism groups tested, whereas the product obtained from grape seed promoted TAMB and LAB growth but delayed Enterobacteriaceae proliferation.

Applications of Wine Pomace in the Food Industry: Approaches and Functions

Winemaking generates large amounts of wine pomace, also called grape pomace. This by-product has attracted the attention of food scientists and the food industry, due to its high content in nutrients and bioactive compounds. This review mainly focuses on the different published approaches to the use of wine pomace and its functions in the food industry. Traditionally, wine pomace has been used to obtain wine alcohol, food colorings, and grape seed oil. More recently, research has focused in the production of other value-added products, such as extracts of bioactive compounds, mainly phenols, recovery of tartaric acid, and the making of flours. The most common functions associated with wine pomace products are their use as antioxidants, followed by their use as fortifying, coloring, and antimicrobial agents. These products have mainly been applied to the preparation of meat and fish products and to, a lesser extent, cereal products.

Adaptation and Validation of QUick, Easy, New, CHEap, and Reproducible (QUENCHER) Antioxidant Capacity Assays in Model Products Obtained from Residual Wine Pomace.

Evaluation of the total antioxidant capacity of solid matrices without extraction steps is a very interesting alternative for food researchers and also for food industries. These methodologies have been denominated QUENCHER from QUick, Easy, New, CHEap, and Reproducible assays. To demonstrate and highlight the validity of QUENCHER (Q) methods, values of Q-method validation were showed for the first time, and they were tested with products of well-known different chemical properties. Furthermore, new QUENCHER assays to measure scavenging capacity against superoxide, hydroxyl, and lipid peroxyl radicals were developed. Calibration models showed good linearity (R(2) > 0.995), proportionality and precision (CV < 6.5%), and acceptable detection limits (<20.4 nmol Trolox equiv). The presence of ethanol in the reaction medium gave antioxidant capacity values significantly different from those obtained with water. The dilution of samples with powdered cellulose was discouraged because possible interferences with some of the matrices analyzed may take place.

Total antioxidant capacity of new natural powdered seasonings after gastrointestinal and colonic digestion

New powdered seasonings, rich in natural antioxidant compounds, have successfully been applied recently in different food matrices. Once ingested, the antioxidants contained in these seasonings may exert protective effects against oxidative stress along the gastrointestinal tract. This fact was evaluated by submitting the different seasonings under study to simulated digestion followed by assessing the reducing and antiradical capacities of the digested fractions. Enzymatic gastrointestinal digestion enhanced 2-3 times both antioxidant activities and colonic fermentation increased more than 10-fold the radical scavenging ability of digested fractions compared with undigested seasonings. Digested fractions derived from the seedless wine pomace seasoning presented generally the highest antioxidant properties. The results were evaluated considering bioaccessibility factors to have a more realistic overview of the potential antioxidant capacities of the seasonings and of the probable beneficial effects of their consumption on the prevention of oxidative damage along the gut.

Effect of a New Natural Seasoning on the Formation of Pyrazines in Barbecued Beef Patties

The formation of pyrazines in food cooking is required to obtain satisfactory “roasted” flavor. The aim of this work was to evaluate the effect of a new red wine pomace seasoning (RWPS) on the formation of pyrazines in barbecued beef patties. Five pyrazines were successfully identified, 2,5-dimethylpyrazine being the most abundant. Although 2-ethyl-5-methylpyrazine was in lower levels, it presented the highest odor units, due to its low threshold. RWPS enhanced the formation of the five identified pyrazines (2.1 times), without relevant changes in the proportion between them. The highest increase was observed for 2-ethyl-6-methylpyrazine (3 times higher than in control). These results were corroborated by electronic nose analysis, presenting RWPS beef patties higher odor intensities. Mechanisms to explain these effects are also proposed in the present work, and the high content of polyphenols seems to be the major cause of the observed results. The use of RWPS could improve the flavor characteristics of meat products or enable using less intense cooking conditions with no changes in the flavor.

Influence of red wine pomace seasoning and high-oxygen atmosphere storage on carcinogens formation in barbecued beef patties

Polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatic amines (HAs) are carcinogenic compounds formed in barbecued meat. Conditions that reduce their formation are of major interest. This study aims to evaluate the influence of red wine pomace seasoning (RWPS) and high-oxygen atmosphere storage on the formation of PAHs and HAs in barbecued beef patties. In general, the levels of PAHs and HAs quantified were low. The storage (9days) promoted higher formation of PAHs in control patties without increase of HAs. RWPS patties cooked at preparation day presented higher levels of PAHs and HAs than control. Nevertheless, RWPS patties cooked after storage presented lower levels of PAHs and HAs than control. ABTS assay pointed out that higher radical scavenging activity may be related to with lower PAHs or HAs formation. In conclusion, RWPS can be an interesting ingredient to inhibit the formation of cooking carcinogens in barbecued patties stored at high-oxygen atmosphere.

The effects of heat treatment on the phenolic composition and antioxidant capacity of red wine pomace seasonings

The impact of thermal processing on the phenolic profile and antioxidant capacity (TAC) of powdered red wine pomace seasonings (RWPSs) obtained from different sources (seedless: Sk-S; whole: W-S; seeds: Sd-S) was assessed. High contents in anthocyanins, flavonol-3-O-glycosides, phenolic acids and flavan-3-ols were found in Sk-S, whereas flavan-3-ols and phenolic acids were the main compounds identified in Sd-S. Reductions in the anthocyanidin and flavonol-3-ol contents mainly determined the effect of heat on the total phenolic contents (Sk-S: -29.4%; W-S: -28.0%; Sd-S: -5.78%), although heating affected positively the phenolic acid and flavonol aglycon contents. Slight TAC decreases were observed in the RWPS-derived extracts (classical Folin-Ciocalteu and ABTS assays). However, higher TAC reductions were detected when the powdered RWPSs were used directly as samples (QUENCHER approach). In conclusion, there is little evidence against submitting RWPSs to thermal processing, as heating affects differently each type of phenolic compound and does not induce very severe TAC decreases in these seasonings.

Applications of Recovered Bioactive Compounds in Food Products

Abstract This chapter focuses on the use of bioactive compounds derived from grape pomace to develop innovative products that provide a source of health-promoting and “clean label” ingredients. It covers the growing interest in replacement of synthetic additives by natural compounds, due to both legal restrictions and consumer demand for natural foods. Moreover, it discusses consumer demand for foods that can help prevent major chronic diseases, while contributing to sustainable use of natural resources. It reviews the multifunctional properties of ingredients derived from grape processing waste. These include their use as antioxidants, colorants, antimicrobials, texture-modifying agents, and fortifying ingredients. Successful food applications are illustrated, comprising examples in various sectors including meat, fish, cereal-based, dairy, and fruit-based products. Thorough information is provided on the type of recovered raw material (whole pomace, skins, or seeds), ingredient formulation (liquid/powder/encapsulated crude extract or purified extract, micronized fiber fraction), and typical levels used in foods. Moreover, the technological advancements made possible by the recovery of these ingredients and their reintroduction into the food chain are discussed.

Alternative natural seasoning to improve the microbial stability of low-salt beef patties

The meat industry is seeking new strategies to reduce the sodium content of meat products without shortening their shelf-life. Natural seasonings as salt alternatives are more appreciated than chemical preservatives and also enable the incorporation of interesting nutrients. The present work studies the potential of a new red wine pomace seasoning (RWPS), derived from wine pomace, to inhibit spoilage growth in beef patties with different salt levels (2%, 1.5% and 1%) held in storage at 4°C. The use of RWPS (2% w/w) improved the microbial stability of the patties, delaying total aerobic mesophilic, and lactic acid bacteria growth, especially in samples with low salt levels. Satisfactory results were obtained in modified-atmosphere and air-packaged patties. RWPS also enabled the incorporation of fiber and phenolic compounds, and increased potassium and calcium levels. In summary, RWPS presented an interesting potential as a seasoning in meat products, enabling salt reduction without compromising their microbial stability.