Iciar Astiasarán

Effect of fat level and partial replacement of pork backfat with olive oil on processing and quality characteristics of fermented sausages

Six formulations of dry fermented sausages were produced in three replications with three initial fat levels (30, 20 and 10%) and two levels (0 and 20%) of pork backfat replacing olive oil. After 4 weeks of fermentation and ripening the fat content of the treatments with 30, 20 and 10% fat level ranged from 38.86 to 43.60%, 25.56 to 26.86% and 19.01 to 20.14%, respectively. Fat level affected (P<0.05) the weight losses, the chemical composition, the Gram -ve bacterial count, the lightness, the texture and the appearance of fermented sausages. Replacing 20% of pork backfat by olive oil affected (P<0.05) the lightness and yellowness of sausages. Fat-reduced sausages without olive oil and low-fat sausages with olive oil had the highest score for odour and taste. However, the appearance of fat-reduced sausages was just acceptable while that of low-fat sausages was unacceptable, because the surface was intensively wrinkled and case hardening had developed. Further research is needed to improve the appearance of these sausages.

Effect of replacing pork backfat with pre-emulsified olive oil on lipid fraction and sensory quality of Chorizo de Pamplona — a traditional Spanish fermented sausage

Six treatments of Chorizo de Pamplona, traditional Spanish fermented sausage, were manufactured under usual commercial conditions by replacing 0, 10, 15, 20, 25 and 30% of pork backfat by pre-emulsified olive oil with soy protein isolate. Sausages with 20-30% replacing level had higher (P<0.05) protein content than control as a result of the addition of soy protein isolate. The oleic acid increased (P<0.05) in sausages with 15-30% replacing level, and linoleic acid increased in sausages with 10-25%. Sausages with 10-25% of substitution had lower total SFA-stearic and higher (P<0.05) total MUFA, total PUFA, (MUFA+PUFA)/(SFA-stearic), and PUFA/(SFA-stearic). Cholesterol content showed reduction about 12-13% in sausages with 20-25% replacing level, and up to 22% in sausages with 30% replacing level. Sausages with 10-25% of substitution were acceptable from the sensorial point of view. The texture and colour instrumental measures were comparable with that of commercial products. No increments in hexanal content were observed. It is concluded that up to 25% of pork backfat can be replaced with pre-emulsified olive oil in the production of Chorizo de Pamplona fermented sausages. Higher replacing levels of pork backfat did not show nutritional advantages in relation to the fatty acid profile and were unacceptable due to considerable dripping of fat during ripening.

Oxysterols: A world to explore

Oxysterols (oxidized derivatives of cholesterol and phytosterols) can be generated in the human organism through different oxidation processes, some requiring enzymes. Furthermore, oxysterols are also present in food due to lipid oxidation reactions caused by heating treatments, contact with oxygen, exposure to sunlight, etc., and they could be absorbed from the diet, at different rates depending on their side chain length. In the organism, oxysterols can follow different routes: secreted into the intestinal lumen, esterified and distributed by lipoproteins to different tissues or degraded, mainly in the liver. Cholesterol oxidation products (COPs) have shown cytotoxicity, apoptotic and pro-inflammatory effects and they have also been linked with chronic diseases including atherosclerotic and neurodegenerative processess. In the case of phytosterol oxidation products (POPs), more research is needed on toxic effects. Nevertheless, current knowledge suggests they may also cause cytotoxic and pro-apoptotic effects, although at higher concentrations than COPs. Recently, new beneficial biological activities of oxysterols are being investigated. Whereas COPs are associated with cholesterol homeostasis mediated by different mechanisms, the implication of POPs is not clear yet. Available literature on sources of oxysterols in the organism, metabolism, toxicity and potential beneficial effects of these compounds are reviewed in this paper.

Analysis of volatile compounds by GC-MS of a dry fermented sausage: chorizo de Pamplona

Abstract The profile of volatile compounds of a typical Spanish dry fermented sausage, chorizo de Pamplona, has been analyzed by GC–MS, using a simultaneous distillation-extraction (SDE) system. Qualitative and quantitative differences were found in the volatile profiles obtained in the five analyzed commercial brands. One hundred and ninety-three different substances were isolated, the group of acids being the most important from a quantitative point of view in all brands, accounting at least for the 60% of the total area. Aldehydes, basically from lipid oxidation, contributed between 7.72 and 13.97% to the total amount. Acids and aldehydes were the chemical families that showed the lowest variability among brands. In contrast, esters showed the highest coefficient of variation among brands (111%), followed by phenols (82%) and terpenes (76%). The variability observed in these three families could be attributed respectively to the different starter cultures, smoking process and spices employed in their production. Butylated hydroxytoluene (added as an antioxidant, E-321) was the third most abundant compound in three of the five brands.

Nutritional assessment interpretation on 22 007 Spanish community-dwelling elders through the Mini Nutritional Assessment test.

OBJECTIVES To evaluate the prevalence of undernutrition among community-dwelling elderly people in Spain using the Mini Nutritional Assessment (MNA) and to analyse its distribution according to age, gender and residence region. DESIGN Cross-sectional study assessing the nutritional status of elderly persons through both the short form and the full version of the MNA test. SETTING Pharmacy offices across the whole country (Spain) were enrolled to recruit participants. SUBJECTS A total of 22 007 participants (8014 men and 13 993 women), aged >or=65 years, assessed during the last two months of 2005. RESULTS According to MNA screening, 4.3 % subjects were classified as undernourished (MNA score <17) and 25.4 % were at risk of undernutrition (MNA score >or=17 to <or=23.5). The MNA short form correlated strongly with the full MNA version (r = 0.85). MNA total score was significantly higher in men than in women (25.4 (sd 3.7) v. 24.6 (sd 3.9); P < 0.001) and lower in the oldest than in the youngest subjects (P < 0.001) in both genders. According to regional distribution, the best nutritional status was found in elderly from the north of Spain excluding the north-west area. CONCLUSIONS Female gender, older age and living in the south half or north-west of the country were associated with higher rates of undernutrition among community-dwelling elderly persons in Spain.

A review of analytical methods measuring lipid oxidation status in foods: a challenging task

Lipid oxidation analysis in food samples is a relevant topic since the compounds generated in the process are related to undesirable sensory and biological effects. Proper measurement of lipid oxidation remains a challenging task since the process is complex and depends on the type of lipid substrate, the oxidation agents and the environmental factors. A great variety of methodologies have been developed and implemented so far, for determining both primary and secondary oxidation products. Most common methods and classical procedures are described, including peroxide value, TBARS analysis and chromatography. Some other methodologies such as chemiluminescence, fluorescence emission, Raman spectroscopy, infrared spectroscopy or magnetic resonance provide interesting and promising results. Therefore, attention should be paid to these alternative techniques in the area of food lipid oxidation analysis.

Enhancement of the nutritional status and quality of fresh pork sausages following the addition of linseed oil, fish oil and natural antioxidants

Fresh pork sausages (pork shoulder, pork back fat, water, rusk and seasoning) were manufactured where 15% of the pork back fat was substituted with linseed oil (LO) or fish oil (FO). Green tea catechins (GTC) and green coffee antioxidant (GCA) were added to both LO (LGTC 200 and LGCA 200) and FO (FGTC 200 and FGCA 200) substituted sausages at a level of 200mg/kg. Raw and cooked pork sausages were either over-wrapped with oxygen permeable film (aerobic storage) or stored in modified atmosphere packages (MAP) containing 80% O(2):20% CO(2) or 70% N(2):30% CO(2), respectively for 7 days at 4°C. Effects on fatty acid profiles, lipid oxidation, colour and sensorial properties were investigated. α-Linolenic acid increased from 1.34% (control) to 8.91% (LO) and up to 11.2% (LGTC 200 and LGCA 200). Addition of fish oil increased levels of EPA from 0.05% (control) to 2.83% (FO), 3.02% (FGTC 200) and 2.87% (FGCA 200) and DHA levels increased from 0.04% (control) to a maximum of 1.93% (FGTC 200). Lipid oxidation was low in raw and cooked linseed oil containing sausages. GTC (200mg/kg) significantly (P<0.05) reduced lipid oxidation in raw fish oil containing sausages after 7 days of storage. Colour parameters in raw pork sausages were unaffected by the packaging atmosphere. L(∗) lightness values were lower (P<0.05) in LGTC 200 and a(∗) redness values lower (P<0.05) in LGTC 200 and FGTC 200 after 7 days of storage. Sensory scores of cooked pork sausages were unaffected by linseed oil addition. Flavour and overall acceptability scores in cooked fish oil containing sausages were improved by GTC addition. Results obtained demonstrate potential for the production of nutritionally enhanced fresh pork sausages.

Nutritional and sensory properties of dry fermented sausages enriched with n − 3 PUFAs

Enrichment of dry fermented sausages with n-3 fatty acids through a partial substitution of pork backfat by deodorised fish oil resulted in improved nutritional properties with regard to conventional sausages, without affecting sensory properties and oxidation status. The developed products supplied 0.64g EPA/100g and 0.46g DHA/100g product, and showed PUFA+MUFA/SFA ratio of 1.76 and n-6/n-3 ratio of 2.97. No signs of oxidation were found in any type of sausages, control and modified. None of the dienals and trienals reported as secondary lipid oxidation products and typical for fish oil were detected in the modified sausages. Instrumental colour differences were detected, however, without relevance in the sensory analysis. The sensory evaluation panel did not find differences in general acceptability. The modified dry fermented sausages can be considered a technologically viable functional food.

Effect of storage and packaging on fatty acid composition and oxidation in dry fermented sausages made with added olive oil and antioxidants

Dry fermented sausages produced by a partial substitution of pork backfat with pre-emulsified olive oil were manufactured and stored (2 and 5 months) using different packaging conditions (aerobic/vacuum piece/vacuum slices) in order to evaluate the intensity of the oxidation process. Also the effect of the addition of butylhydroxytoluene (BHT) and butylhydroxyanisole (BHA) to one of the modified batches was studied. Addition of olive oil, especially with antioxidants, was more effective than using vacuum storing methods in avoiding lipid oxidation during storage. After 5 months of storage at 4 °C, the combination of the increase in oleic acid and the preservation of PUFA by the antioxidant activity of the olive oil emulsion and antioxidants (when added), lead to better MUFA+PUFA/SFA ratios in olive oil containing sausages (1.90-1.98 g/100 g fatty acids) and particularly in antioxidants containing sausages (2.02-2.16 g/100 g) than in control ones (1.72 g/100 g). Vacuum packaging of the piece was the best method to minimise formation of lipid oxidation volatile compounds.

Characterization of chorizo de Pamplona : instrumental measurements of colour and texture

A study of standardization of chorizo de Pamplona by instrumental measurements of colour and texture was carried out in five different commercial brands of this typical Spanish dry fermented sausage. Parameters related to colour showed little variability among brands, especially in L∗ and a∗ values. The higher variability of b∗ could be related to the different amounts of paprika used in the formulations. Low ranges of variation were found in texture parameters. Some observed differences, especially in cohesiveness were significantly correlated with the pH of the products. Multivariate analysis, based on colour and texture parameters, led to 2 principal components which explained 80.80% of the total variance. Brands 1 and 5 appeared to be the most similar in function of the first component, which was mainly defined by hardness followed by gumminess, a∗ and b∗.