RESUMEN
White grape pomace (winery by-product) stabilized by blanching and high hydrostatic pressure has recently been successful at delaying lipid oxidation in burgers. The aim of this study was to investigate whether it can also delay lipid oxidation in dry-cured sausages, and to compare its effect when added at 0.5 and 3% with those of synthetic additives (sodium nitrite and ascorbic acid) and no additives (Control) in lipid and protein oxidation, the instrumental color, the sensory characteristics, and the volatile compounds. The pomace (68.7 ± 7.4 mmol Trolox g-1) was as effective as the additives at preventing lipid oxidation, resulting in values 3.2-3.8 times lower than the Control sausages. However, the pomace was not effective at decreasing the microbial counts, improving the instrumental and sensory color and the volatile compound profile, and decreasing the off-odor and off-flavor developed in the Control sausages. The lack of a detrimental effect of the pomace at 0.5% on the volatile compounds and the sensory characteristics and its benefits to delay lipid oxidation suggest that it might be useful to improve the oxidative stability. Conversely, at 3%, with a detrimental effect on some sensory characteristics and no benefits over the lower dosage, is not advisable.
RESUMEN
Lupin seeds have received increased attention due to their applications in the nutrition of humans and livestock. One of their special features is their high content of dietary fiber, which is influenced by the lupin species. No previous studies have focused on the variability in dietary fiber and its fractions within species so far. The aim of this study was to investigate the variability within L. albus and L. angustifolius (eight cultivars each) in the dietary fiber composition expressed as low-molecular-weight soluble dietary fiber (LMWSDF), soluble and insoluble non-cellulosic polysaccharides, cellulose, and Klason lignin. Additionally, we analyzed the proximate composition and the composition of amino acids and fatty acids. The results showed noticeable variability within both species not only in the total dietary fiber but also in all its fractions, especially in LMWSDF, cellulose, non-starch polysaccharides, and Klason lignin within L. angustifolius. This indicates that the cultivar choice should be based on the application for which it is used. Even though important nutrients, such as the most indispensable amino acids, are not highly variable within L. albus, dietary fiber variations can still have a marked influence on the nutritional value because of their influence on the digestibility of other nutrients.
RESUMEN
Chitosan coatings have been investigated for improving food shelf-life. The addition of an olive leaf extract could enhance its beneficial effect. The aim of this study was to evaluate the effectiveness of an olive leaf extract added to a chitosan coating in delaying deterioration in refrigerated pork burgers without additives packaged under a 40% oxygen and 60% carbon dioxide modified atmosphere. Some general parameters (microbial counts, instrumental color and texture, and lipid and protein oxidation) were measured over the storage of pork burgers without coating (Control), with a chitosan-based coating (Chitosan) and with a chitosan-based coating enriched with an olive leaf extract (Chitoex). The coating impacted the effect of the storage time on most parameters. Both coatings were especially effective at limiting the changes that occur over time in the headspace gases, some texture parameters (hardness, gumminess, and chewiness) and lipid oxidation, although the effect on the microbial counts was weak. Chitoex was more effective than Chitosan at preventing changes in the headspace gases on day 11 and in lipid oxidation on all the sampling days. In conclusion, the Chitoex coating could be useful for prolonging the storage of pork burgers by preventing changes in texture and reducing lipid oxidation.
RESUMEN
The main purpose of this study was to evaluate the effect of high-pressure processing (HPP) and storage temperature on the microbial counts, the instrumental color, and the oxidation stability of sliced dry-cured Iberian loin from two categories and two leading companies. 600 MPa for 8 min was sufficient to decrease all the microbial counts without affecting the color and the oxidation status, the effect being modulated by the loin category and company, whose effect on those variables was marked. However, the subsequent 90-day storage softened the initial effect of HPP on microorganisms and allowed a significant effect of HPP to develop on color and oxidation. In addition, the coliform counts were higher after storage at 20°C than at 4°C, suggesting that refrigeration may be needed during long-term storage to ensure loin safety.
RESUMEN
Although deep frying is widely used, little is known about the effect of frying different meats on the frying oil. The aims of this study were to investigate whether the pork type influences the characteristics of the frying oil, to compare any effects with those of French fries, and to research whether the use of thermally damaged oil differentially affects those products. French fries and pork from pigs reared outdoors on acorns and grass (outdoor) or indoors on a concentrated feed (indoor) were deep-fried in either raw or previously heated olive oil. The type of product affected most color parameters, K268 and the α-tocopherol content of the oil. The frying of outdoor pork hardly affected the α-tocopherol content, whereas the frying of indoor pork and especially French fries caused a significant decrease. This suggests that the meat type should be considered when setting the frying lifespan of olive oil. Regarding the fried products, L*, moisture (only French fries) and the malondialdehyde (MDA) content (only indoor pork) were the only parameters affected by the previous oil damage. The outdoor pork was less susceptible to oxidation than the indoor pork when the oil was severely damaged. Therefore, pig outdoor-based systems based on antioxidant-rich diets might be convenient to maintain oxidation at the lowest level after frying.
RESUMEN
The aim of this study was to research the effect of the genetic background (Retinto, Torbiscal, and their reciprocal crosses) on the subcutaneous fatty acids and the sensory characteristics of dry-cured shoulders from Iberian pig, and also to investigate whether there is some interaction between genotype and diet composition when pigs are reared indoors, to obtain information to improve the selection strategies for purebred Iberian pig. The genetic background affected both the fatty acid composition (C17:0, C17:1 n-7, C18:3 n-3 and C20:0 were significantly different) and the sensory characteristics (marbling, lean fibrousness, and flavour intensity and persistence were significantly influenced), which indicates that they should be taken into account in the selection strategies for purebred Iberian pig. In a similar way, the genotype × diet composition interaction also should be taken into account when selecting a genetic line or cross to be fed indoors on a particular diet because of its repercussion on the sensory characteristics.