Taste compounds in chorizo and their changes during ripening

Taste compounds in chorizo—a dry fermented sausage—prepared by both traditional and industrial methods, i.e. D- and L-lactic acid, acetic acid, free amino acids and ATP derivatives, were analysed. Industrial chorizo contained larger amounts of D-lactic, L-lactic and acetic acids, several amino acids (e.g. γ-aminobutyric acid, phenylalanine) and hypoxanthine (Hx) than the traditional one (p < 0.05). The variations in taste compounds during the ripening of chorizo were tracked. D-Lactic and acetic acid increased, as well as most of the amino acids. ATP derivatives showed characteristic changes, IMP decreased on the first day and inosine (Ino) changed gradually to Hx during ripening. The taste compounds contents of garlic and paprika were studied. There was an important contribution of asparagine from spices to the initial mixture of sausage.     

Lipid and cholesterol oxidation in chicken meat are inhibited by sage but not by garlic

The effects of the addition of sage and garlic in chicken meat on lipid and cholesterol oxidation, having as prooxidant factors the addition of salt, thermal treatment, and frozen storage, were evaluated. The content of unsaturated fatty acids did not change in the presence of sage; on the contrary, with garlic, the content of these fatty acids decreased after cooking and storage. Hexanal and pentanal contents were lower in patties containing sage, and higher in those with garlic. The 7-ketocholesterol was the cholesterol oxide found in higher amount in raw chicken on day 0, while the formation of 7β- and 7α-hydroxycholesterol was verified only from day 30 on. Cooking and storage resulted in increase of total cholesterol oxides and decrease of α- and γ-tocopherol. Sage was effective in controlling lipid and cholesterol oxidation, minimizing the prooxidant effects of salt, cooking, and storage. However, garlic presented no effect as antioxidant and accelerated lipid oxidation. PRACTICAL APPLICATION: The addition of sage to chicken meat (0.1 g/100 g) is a good alternative to prevent and delay the formation of compounds derived from lipid oxidation that are responsible for off-flavors and loss of nutritional quality during long-term frozen storage. Care must be taken when using garlic to seasoning chicken meat products, such as hamburgers and meatballs, especially cooked or precooked due to its potential to promote lipid oxidation and consequently raising the risk of having the product rejected by the consumer.     

Influence of the paprika type on redness loss in red line meat products

Paprika, with its high colourant power (measured in ASTA units), imparts higher initial redness to fresh red sausage and fresh chorizo (red line meat products). This higher degree of redness (measured according to the red–green component, a∗, and spectrophotometric colour units) is maintained until the end of the products’ shelf life. However, the pasteurization necessary to reduce the microbial load of paprika can cause alterations to its stability. The addition of natural antioxidants to pasteurized paprika (rosemary extract) was seen to maintain the colour levels of meat products throughout their shelf life. Differences in the colour of meat batches elaborated with paprika of different colourant power could be detected by consumers in a hedonistic test, who evaluated the colour positively.     

Antioxidant/prooxidant properties of model phenolic compounds: Part I. Studies on equimolar mixtures by chemiluminescence and cyclic voltammetry

The electrochemical behaviour and the antioxidant effectiveness of ascorbic acid (AA), caffeic acid (CA), quercetin (Q), catechin (Cat), hesperetin (H) and their equimolar binary mixtures were evaluated by means of cyclic voltammetry and luminol Co(II)–EDTA chemiluminescence, respectively, with a view to the prediction of a potential prooxidant or synergistic behaviour of mixtures of antioxidants. An important synergistic oxidation between Q and Cat was observed. The mixture CA/AA manifested the most prooxidant tendency among all the tested compounds and their mixtures. AA increased the antioxidant activity of Q and decreased that of Cat. Q and Cat regenerated CA, the prooxidant effect of the mixtures increasing with less e-delocalisation. Cat and CA have an antagonistic effect. H has the closest oxidation potential to CA and a slight increase of its antioxidant activity was registered when mixed with CA, which was not the case when it was combined with the other compounds or measured alone.     

LIPID OXIDATION IN TURKEY MEAT AS INFLUENCED BY SALT,METAL CATIONS AND ANTIOXIDANTS1

Turkey breast or thigh muscle was mixed with 2% pure salt, rock salt, or pure salt plus 50 ppm of one or a combination of copper, iron or magnesium. Efficacy of 2 antioxidants was tested. Lipid oxidation was monitored during refrigerated and frozen storage of raw and cooked turkey by the thiobarbituric acid (TBA) test. TBA results indicated that the most significant prooxidant effect was caused by salt plus Cu²⁺ and Fe²⁺ followed by salt plus Fe³⁺ or Cu²⁺ alone. Tenox 6 was an effective antioxidant in the presence of copper and iron ions. Thigh meat was more susceptible to oxidation than breast meat. Cooking had a significant prooxidant effect as measured by TBA.     

Identification of Antioxidants in Aged Garlic Extract by Gas Chromatography-Mass Spectrometry and Liquid Chromatography-Mass Spectrometry

A novel aged garlic extract, with high antioxidant activities, was prepared by soaking sliced garlic in 10% ethanol solution for 90 days. In order to locate the antioxidant ingredients of aged garlic extract, 2,2-azinobis-6-s (3-ethylbenzothiazoline sulfonic acid) assay, hydroxyl free radical assay, 2,2-diphenyl-1-picrylhydrazyl assay, and ferric reducing/antioxidant power assay were conducted to guide the fractionation of aged garlic extract by means of extraction. As a result, the ethyl acetate fraction was identified as the highest antioxidant activity in aged garlic extract. Therefore, the ingredient information of the ethyl acetate fraction were obtained through gas chromatography–mass spectrometry and ultra performance liquid chromatography mass spectrometry / mass spectrometry analysis. Some phenols and diallyl disulphide, 5-(hydroxymethyl)-2-furancarboxaldehyde, S-allyl-cysteine, S-allyl-mercaptocysteine, and 1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid were identified as potent antioxidants in aged garlic extract by gas chromatography–mass spectrometry and ultra performance liquid chromatography mass spectrometry / mass spectrometry, respectively. The biological activities and formation mechanisms of these identified compounds were discussed.     

The effect of different paprika types on the ripening process and quality of dry sausages

The main objective of the study was to evaluate the effects of large amounts of paprika and different amounts of hot paprika on the ripening process of dry sausage. The sausages, called ‘chorizo’ were evaluated for changes in texture, colour and physico‐chemical parameters, including rancidity. The results show that when either paprika contents or concentrations of hot paprika were increased, compared with a control, the ripening process of dry sausages was accelerated, probably by the promotion of lactic acid bacteria growth, which, in turn, lead to a fast drop in pH and water activity. These effects cause a rapid development of texture when compared with a suitable control, with an optimal hardness being reached in less time. These products have greater colour intensity, which remains more stable, together with lower malonaldehyde contents than controls. It was shown that paprika, especially the hot variety, exerts a protective effect against rancidity.     

Volatile compounds in chorizo and their changes during ripening

The volatile compounds extracted from both traditional and industrial chorizo—a dry fermented sausage—were analysed by gas chromatography/mass spectrometry (GC/MS). One hundred and twenty-six peaks were detected relating to volatile extracts of which 115 were identified. The substances identified belonged to several classes of chemical: acids, alkanes, alcohols, aldehydes, sulphur compounds, ketones, esters, ethers, phenolic compounds, aromatic hydrocarbons, lactones, nitrogen compounds, terpenes, chloroform and benzofurane. Among the major compounds isolated were acetic acid, allyl-1-thiol and phenol. Larger quantities of most of the chemical groups were found in industrial compared to traditional chorizo, except for sulphur compounds. Typical breakdown products derived from lipid autooxidation were virtually negligible in chorizo. Of the chemicals isolated, sulphur compounds, phenols, acids, ethyl esters and carbonyls could have particular importance to the overall chorizo flavour. In addition, the changes in the proportions of volatile compounds during the ripening of chorizo were tracked. Most of the volatiles increased during ripening, especially acids, alcohols, esters, phenols, ketones and terpenes. On comparing the distribution of the sulphur compounds observed in chorizo with that of garlic, some noteworthy differences were observed. The reason for these differences is based upon several transformations of the sulphur compounds derived from garlic during the ripening and storage of chorizo.     

Antioxidant properties of Mediterranean spices compared with common food additives

In this study, the antioxidant properties of Mediterranean food spices (annatto, cumin, oregano, sweet and hot paprika, rosemary, and saffron) at 5% concentration and of common food additives (butylated hydroxyanisole [BHA], butylated hydroxytoluene [BHT], and propyl gallate) at 100 microg/g are compared. The ability of these compounds to inhibit lipid peroxidation was, in decreasing order, rosemary > oregano > propyl gallate > annatto > BHA > sweet paprika > cumin > hot paprika > saffron > BHT. Deoxyribose damage is partially inhibited in the presence of cumin extract that exhibits the strongest protective action. The rest of the spices also protect deoxyribose better than the BHA and BHT used in the assay. Finally, the results obtained in the assay point to the prooxidant effect of propyl gallate. Hydrogen peroxide scavenging activity is measured by using peroxidase-based assay systems. In aqueous medium, the spice extracts show lower antioxidant activity than propyl gallate, the decreasing order being cumin > oregano > annatto > rosemary > hot paprika > sweet paprika. BHA and BHT did not scavenge H2O2 Spices are able to scavenge HOCl and protect alpha1-antiproteinase. The results indicate that rosemary and oregano are more effective HOCl scavengers than the other substances analyzed, which, in decreasing order, were propyl gallate, annatto, sweet and hot paprika, saffron, and cumin. The effect of Mediterranean food spices on the oxidative stability of refined olive oil tested by the Rancimat method was compared with common food additives during storage (72 h, 2, 4, and 6 months) at room temperature. The results showed that the spice extracts analyzed have significant stabilizing effects (P < 0.05).     

Antioxidant activity of carotenoids against the oxidative destabilization of sunflower oil-in-water emulsions

The antioxidant activity of carotenoids (β-carotene, lycopene, paprika, marigold, bixin- and norbixin-rich annatto extracts) was estimated in sunflower oil-in-water emulsions (o/w) stabilized either by Tween 20 or by a mixture of Tween 20 and sodium caseinate at equal concentrations. Both polar (paprika, marigold, bixin, norbixin) and hydrophobic (β-carotene, lycopene) carotenoids exerted a clear antioxidant effect during thermal accelerated autoxidation (60 °C) of o/w emulsions stabilized by Tween 20, while in the protein-based emulsions only polar carotenoids acted as antioxidants against the production of primary and secondary oxidation products. Furthermore, o/w emulsions, containing different concentration of paprika and bixin-rich annatto extract (0.25–1.5 g/L) in the lipid phase oxidized slower than the control emulsions. Meanwhile, the rate of carotenoids' degradation revealed that polar carotenoids, which presented antioxidant effect in both protein and Tween 20 stabilized emulsions, presented a higher rate of degradation than the hydrophobic carotenoids.     

模糊数学评价与响应面结合研制黑蒜茶树菇酱及抗氧化活性分析

以黑蒜、茶树菇和小米椒为主要原料,以感官评价为标准,采用单因素实验、模糊数学评价和响应面优化法,对黑蒜茶树菇酱的茶树菇、小米椒、植物油、食用盐、白糖、淀粉、葱姜蒜等原料配方进行优化,研究一款黑蒜酱制品,并将其与市售春玖源茶树菇酱进行抗氧化活性对比。结果表明:黑蒜茶树菇酱最佳配方为:黑蒜20 g,茶树菇18.05 g、小米椒3.49 g,植物油6.96 g、食用盐3.48 g、白糖1.16 g、淀粉2.32 g、葱姜蒜各1.16 g,感官评分为88.26分。黑蒜茶树菇酱与春玖源茶树菇酱对DPPH自由基、羟自由基、超氧阴离子自由基等均具有清除能力,对Fe³⁺具有还原能力,与体积浓度呈现正相关的量效关系,黑蒜茶树菇酱的清除能力和还原能力均优于市售春玖源茶树菇酱,当体积浓度达到1 mL/mL时,对DPPH自由基、羟自由基和超氧阴离子自由基的清除率分别达到了93.6%、75.9%和50.8%,对Fe³⁺还原能力也达到最大,说明制备的黑蒜茶树菇酱具有良好的抗氧化性。理化及微生物指标检测结果表明,水分含量52.35 g/100 g,总酸含量2.02 g/k...     

Garlic (Allium sativum L.) and ready-to-eat garlic products: In vitro antioxidant activity

Garlic contains polyphenol and sulphur compounds, which are responsible for its antioxidant activity (AA). This study aimed at evaluating the AA of fresh garlic and its commercialised products and their shelf life. Fresh garlic (FG) and its products, i.e. chopped with salt (CGS), chopped without salt (CG), fried (FRG) and mixed garlic (FG with dehydrated garlic; MG) antioxidant activity was evaluated by three different methods: DPPH (1,1-diphenyl-2-picrylhydrazyl) assay, β-carotene/linoleic acid assay and Rancimat^® method. Amongst all the analysed products, fried garlic presented the highest antioxidant activity. The free radical-scavenging activity decreased during the shelf life of all analysed products that correlated with the decrease in the total polyphenol content. Our findings suggest that some compounds other than phenol may have contributed towards this outcome.     

Effect of the use of a commercial phosphate mixture on selected quality characteristics of 2 Spanish-style dry-ripened sausages

Abstract: The aim of this study was to evaluate the usefulness of the addition of a commercial phosphate mixture in 2 dry‐ripened Spanish‐style sausages: “salchichón” and “chorizo.” Three batches of each of those sausages were prepared with low and high levels of phosphates, and selected quality variables (moisture, pH, a_w, lactic and acetic acid, α‐amino nitrogen, total free fatty acids, thiobarbituric acid reactive substances, microbial counts, color, and texture analysis) were compared against controls. Furthermore, phosphate‐added and control sausages were ranked by consumers in order of preference. In “salchichón,” phosphate addition resulted in a significant (P < 0.05) increase in drying rate, and tendencies (not significant) toward a decrease in lipid oxidation and an increase in hardness and chewiness. In “chorizo,” the addition of phosphates resulted in higher hardness, elasticity and chewiness, and lower yellowness (P < 0.05). In the manufacture process of dry‐ripened sausages, phosphates can be considered as additives with potential enhancement effect in drying and eating quality. Practical Application: The main outcome from the present study is to find evidence on which points of reference could be drawn for the technological application of phosphates in dry‐ripened sausages. It has been observed that the drying rate and several eating quality characteristics can be enhanced with the use of phosphates.     

Oxidative rancidity in avocado purée as affected by α-tocopherol, sorbic acid and storage atmosphere

Avocado is nutritionally rich in many health-related components and a valuable energy source due to their high quality fat content. The aim of this work was to evaluate the lipid oxidation of refrigerated avocado purée as affected by the addition of α-tocopherol and/or sorbic acid with antioxidant and antimicrobial purposes, respectively. Hence, the formation of hydroperoxides and secondary oxidation products was studied throughout storage under different modified atmosphere packaging conditions. Addition of α-tocopherol clearly reduced rancidity of the lipid fraction. When the antioxidant was added, hydroperoxide formation was inhibited for a period of at least 12 weeks with little effect of the presence of sorbic acid and O₂ availability. On the contrary, absence of α-tocopherol in the product formulation preceded the production of secondary oxidative metabolites and a rapid saturation of the fatty acid chains. Sorbic acid was found to have a moderate prooxidant effect (p < 0.05). This detrimental influence on the lipid phase of avocado should be weighted up against the antimicrobial effect in order to evaluate its capability of extending the shelf life of avocado products.     

超微粉碎对黑蒜粉末物理性质及抗氧化能力的影响

为评价超微粉碎对黑蒜粉末物理性质及抗氧化能力的影响,分别对超微粉碎与机械粉碎黑蒜粉末的休止角、松密度、持水性等理化性质进行比较分析,测定其多酚类物质提取率,同时采用DPPH自由基清除、Fe3+还原能力、ABTS+自由基清除能力、氧自由基吸收能力系统评价其体外抗氧化能力。并以人肝肿瘤细胞HepG2细胞为模型,测定其不同粉碎方式黑蒜的细胞抗氧化能力。结果显示,与机械粉碎相比,超微粉碎后的黑蒜粉末平均粒径较小,水溶性、溶胀度及多酚类物质的溶出率分别增加了26.84%、39.53%和31.76%,持水力及持油力等理化性质得到改善。抗氧化能力评价中,超微粉碎能力显著提高了黑蒜粉末的还原能力、DPPH和ABTS+自由基清除能力、总氧自由基吸收能力以及细胞内抗氧化活性。     

The antioxidant properties of baechu-kimchi and freeze-dried kimchi-powder in fermented sausages

The antioxidant properties of baechu-kimchi in fermented sausages were evaluated by investigating its effect on the changes in total free fatty acid content, peroxide value, and TBARS during ripening. The conditions for its antioxidant effectiveness were optimized in a model system (beaker sausages). For this, the conditions of added kimchi – form (kimchi and freeze-dried kimchi-powder), fermentation temperature (7 and 20 °C) and concentrations (5%, 10% and 15%) – were varied. The results were compared with that of the control without kimchi. According to the evolution of peroxide value and TBARS, the addition of 5% and 10% kimchi clearly indicated retardation of the development of lipid oxidation. However, an increase in the amount of kimchi added caused a prooxidant effect. The antioxidant effect of kimchi has been found to be dependant on its fermentation temperature as the batches treated with kimchi fermented at 20 °C displayed better protection against the formation of oxidative products than those fermented at 7 °C. Kimchi-powder did not show any antioxidant properties.     

Effect of pork fat addition on the volatile compounds of foal dry-cured sausage

The effect of fat content on volatile compounds from foal dry-cured sausage was studied. Three batches (10 units per batch) of dry fermented sausages with different pork back fat content (5%, 10% and 20%) were manufactured; low fat (LF), medium fat (MF) and high fat (HF), respectively. A total of 45 volatile compounds were extracted by purge-and-trap and identified by GC-MS in the headspace of the batches. The mixture comprised 11 terpenes, 15 esters, 14 hydrocarbons and 2 alcohols. Spices were responsible for the generation of 14 volatile compounds comprising terpenes and hydrocarbons. After 49 days of ripening volatile compounds from spices represented 52.9, 38.9 and 31.2% of the total area for samples from LF, MF and HF batches, respectively, while lipid autooxidation was responsible for the generation of 8 volatile compounds. The PCA offered a good separation of the mean samples according to their fat content.     

A kinetic study of the competitive oxidation of oleic acid-linoleic acid mixtures

The kinetics of the autoxidation of oleic acid-linoleic acid mixtures have been investigated by the rate of oxygen uptake. Mixtures with different molar fractions were prepared, keeping the total number of moles constant. Oxidations were carried out at 30 °C and graphs were made of the percentage of oxidation against time, overall first order rate constant against molar fraction and overall second order rate constant against molar fraction. It was found that during the mono-molecular decomposition of hydroperoxides, the reaction rates decrease with decreasing linoleic acid molar fraction. No prooxidant or antioxidant effects were observed during this period, the predominant effect being that of oleic acid acting as a diluent for the oxidation of linoleic acid. When the reaction enters the period of bimolecular decomposition of hydroperoxides, a slight antioxidant effect was found, for mixtures containing less than 25% oleic acid. With increasing oleic acid concentration this effect levels off and gives way to a more marked prooxidant effect when the oleic acid is above 75%.     

大蒜、胡萝卜、芹菜复合保健饮料的研制

对大蒜、胡萝卜、芹菜复合保健饮料的生产工艺作了研究。结果表明,将45%复合蔬菜汁加入食盐、柠檬酸进行调配,制成的保健饮料口感、色泽、营养俱佳。