M.J. Beriain

Shelf life of beef from local Spanish cattle breeds stored under modified atmosphere

Beef steaks from six Spanish cattle breeds (Asturiana de los Valles, Morucha, Parda Alpina, Pirenaica, Rubia Gallega and Retinta) were packaged under modified atmosphere (60% O(2), 30% CO(2) and 10% N(2)). Water loss, pH, thiobarbituric acid values (TBA), aerobic plate counts, lactic acid bacteria and Enterobacteriaceae counts, CIE L*a*b* colour values and the sensory properties of odour and colour were recorded before packaging (day 0) and after 5, 10 and 15 days of storage. A significant interaction (P<0.05) between breed and storage time was found for all variables, except water loss. Values of pH were between 5.3 and 5.6; maximum water loss (2.64%) was reached after 10 days of storage; aerobic plate counts, lactic acid bacteria and Enterobacteriacea counts were lower than 10(7) CFU/g, and L* increased with storage time while a* decreased (P<0.05). The maximum shelf life of beef assessed by sensory evaluation (regarding colour and odour degradation) was between days 5 and 10 in meat from Retinta breed and between days 10 and 15 in meat from the other breeds, shelf life was probably limited by lipid oxidation.

Colour stability of beef from different Spanish native cattle breeds stored under vacuum and modified atmosphere

Beef steaks from five Spanish cattle breeds were submitted to three packaging conditions: (a) 15 days under vacuum, (b) 15 days under modified atmosphere (MAP) (60% O(2), 30% CO(2) and 10% N(2)), and (c) 10 days under vacuum plus 5 days more under MAP. CIE L(∗)a(∗)b(∗) coordinates, chroma (C(∗)) and hue (H(∗)), relative concentration of myoglobin, oxymyoglobin and metmyoglobin at the meat surface and sensory evaluation of colour were determined 0, 5, 10 and 15 days after packaging. Beef under MAP showed higher lightness (L(∗)) and hue (H(∗)) and lower redness (a(∗)) and chroma (C(∗)) than beef under vacuum. Colour of beef under MAP was not acceptable after 15 days of storage, due to the high metmyoglobin concentration. Yellowness (b(∗)) was the indicator of differences due to ageing and differences in colour between breeds were related to L(∗), a(∗) and H(∗) values. Packaging conditions had a greater effect on beef colour than breed, but breed differences might change with packaging atmosphere. Both packaging and breed are major factors in packaged beef quality.

Cured colour development during sausage processing

A study of colour evolution in dry cured sausage manufactured using industrial technology was made. Parameters which define changes related to nitrosation during curing were determined. The main changes in the colour characteristics of Spanish sausage took place during the fermentation stage. pH, nitrate and nitrite concentration, pigment nitrosation index, pigment discoloration index, a(∗), b(∗), C(∗) and H(∗) values decreased during this stage. However, the nitrosation of the myoglobin pigment continued during the whole curing process. The percent conversion of total pigments to the cured nitric oxide heme pigment form was about 70% in the minced mix, and it increased gradually to about 90% in the final product. During fermentation nitrites reacted with myoglobin (Mb) to form nitrosomyoglobin (NOMb) and metmyoglobin (MetMb), which reduced to NOMb during the drying process.

Carcass characteristics and meat quality of male and female foals.

This research was conducted to characterize the carcass traits and meat quality of 16-month and 24-month old foals (33 males and 23 females) reared in two different livestock production systems. The carcass parameters assessed were conformation, degree of fatness, morphology, weight and carcass meat colour. The physicochemical characteristics and sensory profile of the M. longissimus dorsi (LD) were determined at 4 days of ageing. The carcass parameters and meat quality traits differed little between colts and fillies. There were significant differences between production systems. Carcasses were characterized by B conformation, 3 of fatness and high dressing percentages (>63%). Foal meat had a high myoglobin content and there were differences between the production systems in the flavour, juiciness, flourness and greasiness of the LD.

Relationship between biochemical and sensory quality characteristics of different commercial brands of salchichon

Abstract The nitrogen fractions (myofibrillar, sarcoplasmic, denatured and non-protein), free amino acid composition, parameters related to fat (iodine index, carbonyl compounds, peroxide value and free fatty acids composition), pH, water activity (aw), moisture and sensory quality characteristics were measured in three commercial brands of salchichon (A, B, C) manufactured in three different industries in order to study the relationship between their biochemical characteristics and their organoleptic quality. The different characteristics and composition of the lipid, nitrogen fractions and free amino acid composition in the three commercial brands led to differences in the organoleptic quality, specially in the texture. The best texture scores were related to a higher insolubilisation of the myofibrillar fraction and a higher water content. The panellists did not notice differences in the flavour among the sausage brands probably due to the addition of black pepper and different spices in the initial mix.

Effect of including linseed in a concentrate fed to young bulls on intramuscular fatty acids and beef color

The effect of varying concentrate composition to include 5% linseed and 200 IU of vitamin E on the growth performance, fatty acid composition, and muscle color during shelf life was assessed in 46 young Pirenaica bulls finished to two fatness levels. Adding 5% linseed lowered the dressing rate without altering daily gain or carcass classification. It likewise did not alter the total saturated, monounsaturated, or polyunsaturated fatty acids in the intramuscular fat, though the percentage of α-linolenic acid and n-3 fatty acids increased significantly while the n-6 fatty acid to n-3 fatty acid ratio decreased. Higher subcutaneous fat cover depth at slaughter increased the total percentage of oleic acid and monounsaturated fatty acids without affecting the percentage of saturated or polyunsaturated fatty acids. Adding 200 IU of vitamin E in addition to linseed did not alter the color of film-wrapped fresh meat during storage in darkness.

Technological suitability of mutton for meat cured products

A comparative study on the technological suitability of mutton and pork for meat cured products was carried out. One type of cured dry sausages was made of mutton and the other of pork, using the same formulation and technological conditions. Thus, the evolution of physico-chemical and microbiological parameters, as well as colour and texture were measured at three different stages of the process: after mincing, after fermentation and after drying. The sensory parameters were assessed in the final product. Both mutton and pork had a similar technological aptitude during processing of cured dry sausages, with a similar evolution of the pH value, a(w) and Lactobacilli counts. The main differences between both types of sausage were observed in texture, colour and in the organoleptic characteristics, having mutton sausages greater cohesivity and more stable and redder colour than pork sausages. Besides, mutton sausages showed an aroma, flavour and texture that were not desirable for the panellists.

Low-fat beef patties with augmented omega-3 fatty acid and CLA levels and influence of grape seed extract.

The effects of raising the omega-3 fatty acid (FA), conjugated linoleic acid (CLA), or omega-3 FA plus CLA levels on beef by means of dietary supplementation and of adding grape seed extract (250 mg/kg meat product) in beef patties stored at 2 ± 1 °C in aerobic packaging under simulated retail display conditions for 6 d was evaluated by measuring the thiobarbituric acid reactive substances (TBARS), pH, and instrumental color measurement values and by means of sensory analysis. The pH, instrumental color measurements, and sensory attribute values for patties made from beef with augmented omega-3 FA and/or CLA contents were similar to the values for the control patties made from beef from animals fed a conventional diet. Adding GSE lowered oxidation levels on day 6 (P < 0.001) and did not affect the instrumental color or sensory analysis results during the display period. This suggests that omega-3 FA and CLA-augmented beef could be used to make low-fat beef patties having characteristics similar to those of conventional beef patties while being more in keeping with currently recommended nutritional guidelines.

Effects of Enrichment with Polyunsaturated Fatty Acids (Omega-3 and Conjugated Linoleic Acid) on Consumer Liking of Beef Aged for 7 or 21 d Evaluated at Different Locations

The effect of different animal diets supplemented with linseed (source of omega-3 fatty acids: n-3) and/or conjugated linoleic acid (CON: control, LIN: 10% linseed, CLA: 2% conjugated linoleic acid, LINCLA: 10% linseed plus 2% CLA) on consumer liking of beef aged for 7 or 21 d was assessed in 3 Spanish cities. Overall, tenderness, juiciness, and flavor liking of beef were evaluated by consumers (n = 720) using 9-point scales. Hedonic scores assigned by consumers did not differ (P > 0.05) for beef from animals fed the different diets and aged for 7 or 21 d. Consumer scores showed an increasing trend in beef liking with aging time. Consumers from Pamplona assigned lower (P < 0.05) hedonic scores for beef liking than consumers from Barcelona and Zaragoza. Linseed and/or CLA can be fed to improve the fatty acid profile in beef with minimal impact on consumer liking. Consumer ratings seem to depend on regional tastes and preferences.

Thermal Analysis of Meat Emulsion Cooking Process by Computer Simulation and Experimental Measurement

The Finite Element Method was used to calculate the heat transfer processes that take place during cooking of meat emulsions formulated with different amounts of pork fat or olive oil. Experimental data acquired in the pilot plant were used to validate the theoretical model obtained by computer simulation. The results indicate that the computer simulation predicts to a good approximation. The most important parameters were cooking time and temperature of the meat emulsions. In addition, the theoretical model provides information about the temperature fields for all points in the meat emulsion. For a given fat content, no differences were found in the thermal properties of the emulsions elaborated with pork back fat or olive oil (p >0.05). Instead, the different fat and water content of the meat emulsion formulation determined the differences in the temperature-time evolution during the cooking process.