Effect of fat score on the quality of various meat products

In the larger Swiss abattoirs the fat score (FS) is determined by default as an indicator of fat quality. The FS refers to the iodine number and is related to the degree of unsaturation of the outer layer of backfat. In a feeding trial with Large White gilts, the FS was determined in 47 carcasses. Meat and fat tissues were prepared for the production of salami (SAL), raw-cured bacon (RCB), pork hamburger (PHB) and Vienna sausage (VIS). In the different meat products, the FS was closely related to the percentage of saturated (SFA: r = −0.49 to −0.79) and polyunsaturated fatty acids (PUFA, r = 0.36 to 0.79) for RCB, SAL and PHB (p ? 0.05), but not for VIS. For RCB, significant correlations with FS were seen for the meat:fat-ratio (r = 0.39), fat firmness (r = −0.31) and one fat oxidation marker (1-octen-3-ol: r = 0.51). The texture (r = −0.60), a_w-value (r = 0.63) and one fat oxidation marker (1-octen-3-ol: r = 0.46) were significantly correlated with FS in SAL. On the whole, only a few variables correlated significantly with FS for SAL and RCB and the corresponding relationships were always linear. No significant correlation between FS and any of the technological and sensorial parameters were found for VIS or PHB.     

Optimization of emulsion characteristics of beef, chicken and turkey meat mixtures in model system using mixture design

Emulsion pH (pHe), emulsion capacity (EC), emulsion stability (ES), emulsion density (ED) and apparent yield stress of emulsion (raw emulsion, AYSe) and emulsion gel (cooked emulsion, AYSg) of beef, chicken and turkey meats and their mixtures were studied using a model system.

Turkey meat homogenate was found to have higher protein concentration than chicken or beef homogenates. The highest pHe, EC and ES values and the lowest ED and AYSe values were found in chicken meat. However, the highest AYSg value was found in chicken–turkey meat mixture. Generally, the increasing amount of chicken meat in mixtures increased EC and ES, and decreased ED and AYSe values. Also, chicken–turkey meat mixtures had lower ES values than the mixtures containing only chicken or only turkey meat. With beef, the addition of chicken and turkey meats improved emulsion characteristics significantly. Optimum levels of beef, chicken and turkey meats were found to be 0–23%, 9–30% and 53–91% respectively.     

Effect of fat quality on sausage processing,texture, and sensory characteristics

Fresh pork sausage was manufactured to determine the effects of animal diet (unsaturated or control) and inclusion of corn oil during processing (0% and 14% fat replacement). Bologna was manufactured to investigate only diet effects. Processing, textural, sensory, visual, and storage characteristics were evaluated. Processing yield was improved 2.9 percentage units in fresh sausage but reduced 1.8 units in bologna in unsaturated compared with control diets. Break strength of fresh sausage was reduced 0.6 kg by oil inclusion. Both unsaturated fat and including oil during processing resulted in softer texture of fresh sausage, while increased unsaturation in bologna resulted in firmer or unchanged textural properties. Fresh sausage with oil was lighter colored (5.3 L* units increased) with more fat smearing. In fresh sausage, lipid oxidation remained below 1 mg/kg MDA during 12 weeks frozen storage. Overall, changes in fat quality minimally affected sausage quality, likely providing acceptable products to consumers.     

A second look at the influence of birth weight on carcass and meat quality in pigs

To re-examine the relationship of birth weight with carcass and meat quality of pigs at market weight, offspring (n=378) of 63 sows were assigned to three birth weight groups; 25% low weight (LW), 50% middle weight (MW), and 25% heavy weight (HW), with runts (<800g) being excluded. LW pigs exhibited the lowest postnatal growth performance, the lowest lean mass and the greatest degree of fatness in terms of perirenal fat compared with MW and HW pigs. Only in females, but not in male castrates, the lean percentage was highest in HW pigs. Characteristics of longissimus muscle technological quality declined either in LW (pH, drip loss) or HW (conductivity, lightness) compared with MW pigs. In contrast, intramuscular fat percentage (IMF) was highest in LW pigs. The results suggest that the most desirable carcass composition is obtained with HW pigs, whereas optimum technological pork quality, except for IMF, is achieved with MW pigs.     

Influence of inulin modification and flour type on the sensory quality of prebiotic wafer crackers

An inulin syrup made from Jerusalem artichoke tubers, either in its commercial form or after ultrafiltration, was freeze-dried and used as a prebiotic ingredient in the small-scale manufacture of wafer crackers. The flours used for the preparation of wafer batters were from wheat, rye or spelt wheat, or 1:1 combinations of wheat flour and rye flour or wheat flour and spelt wheat flour. Batter viscosity was strongly influenced by the selection of the flour type, but remained within technologically acceptable limits. The ultrafiltration of the inulin syrup, using a 1 kDa membrane, resulted in a significant reduction of the content of free sugars and minerals which, in turn, had a significant impact on the CIE-Lab color values of the wafer crackers. Using spelt wheat flour instead of wheat flour significantly increased wafer cracker firmness measured by penetration, as did the incorporation of ultrafiltered freeze-dried instead of native freeze-dried Jerusalem artichoke syrup. Sensory analysis revealed a significant influence of product formulation on appearance, flavor and texture of the wafer crackers. It can be concluded from quality scores, which were calculated by using weighting factors assigned to the sensory attributes, that wheat flour may be partially replaced by rye flour or spelt wheat flour without negatively affecting the sensory properties of the wafer crackers.     

Relationships between meat quality measurements in rabbits fed with three diets of different fat type and content

Two hundred and eighty-four, genetically similar (a three-way cross), young rabbits were fed ad libitum, from weaning, either a commercial diet (group C, ether extract 2.6%) or a diet containing vegetable fat (group V, ether extract, 9.9%) or animal fat (group A, ether extract 11.7%). A principal component (PC) analysis was performed with the variables: ultimate pH at 24 h post mortem measured in the longissimus dorsi (LD) and in the biceps femoris (BF) muscles, colour measured on the surface of the loin, fatty acid composition of perirenal fat, meat fat content of the hind leg, water holding capacity and cooking losses of the meat, and sensory variables determined by a trained panel test. The four first PC explained 62% of the total variation (27, 13, 11 and 11%, respectively). The first PC grouped the fatty acids, the second PC grouped the sensorial variables, and the third and fourth PCs grouped the pHs and the water holding capacity. The projection of the data in the first two PCs showed three separate groups of points. Animals fed with diet V were on the left side of the graph, where the variable C18:2 lies, whereas animals fed with diets A and C lay on the right side of the graph, where the saturated acids were grouped. These were slightly separated by the higher content of oleic acid in the animals fed with diet A. The second PC, where the sensorial variables were grouped, did not separate the animals fed with diets A, V and C. The diets used in this experiment had only a slight influence on the organoleptic characteristics of rabbit meat.     

Effect of concentrate feeding pattern in a grass silage/concentrate beef finishing system on performance, selected carcass and meat quality characteristics

Steers were offered grass silage ad libitum and 6.4 kg concentrates daily for 126 days or silage ad libitum for 35 days, followed by concentrates ad libitum (Experiment 1). Steers were offered grass silage ad libitum and 6 kg concentrates daily for 154 days, concentrates ad libitum or grass silage ad libitum for 112 days followed by concentrates ad libitum (Experiment 2). All treatments received the same total concentrate allowance. In Experiment 1, there was no difference in any measurement of meat quality. In Experiment 2, ad libitum concentrate feeding per se, decreased redness and increased shear force of muscle at 2 days post-mortem. Delaying concentrate feeding decreased fat yellowness, decreased shear force at 7 and 14 days post-mortem and increased muscle redness at 14 days post-mortem. Modifications of the beef production system examined had minor effects on beef quality which are unlikely to be of commercial significance.     

添加芹菜粉替代亚硝酸盐对腌肉制品品质的影响

新鲜芹菜中亚硝酸盐含量极低,硝酸盐含量较高,向肉制品添加芹菜粉替代亚硝酸盐,可使肉制品获得特有品质。向对照组加入100mg/kg的亚硝酸钠,处理组1、处理组2、处理组3中分别加入0.2%、0.3%、0.4%的芹菜粉,并设空白组。结果表明,添加芹菜粉0.3%、0.4%后,腌肉的肉色黄度小于对照组,其中添加0.3%芹菜粉能使腌肉外观色泽更鲜红、饱满。腌制10d后,对照组与实验组亚硝酸盐残留量之间差异显著(p<0.05);30d时,添加0.3%芹菜粉腌肉亚硝酸盐残留量为7.46mg/kg,分别比对照组和添加0.4%芹菜粉组低53.58%、8.89%。腌制后期,添加0.3%、0.4%芹菜粉的腌肉丙二醛、挥发性盐基氮含量分别低于对照组,表明芹菜粉具有一定抗氧化效果。综合各因素,肉品腌制中选择添加0.3%芹菜粉替代亚硝酸钠有望取得较好效果。      

Effect of the type of fat on the physicochemical,instrumental and sensory characteristics of reduced fat non-acid fermented sausages

Four batches of reduced fat non-acid fermented sausages were manufactured with pork-ham lean, and the addition of no fat (Lean), 5% pork backfat (BF), 5% sunflower oil (SO) and 5% diacylglycerols (DAGs). The effect of the type of fat as pork-fat substitute on some physicochemical parameters, instrumental color and texture and sensory attributes of the sausages was studied. Results showed that reduced fat non-acid fermented sausages containing less than 12.5% of fat (BF, SO and DAGs) had a good overall sensory quality. This means a fat reduction of more than 70% compared with the average fat content of standard fermented sausages of similar characteristics. Sausages with SO showed higher sensory ratings in desirable ripened odor and flavor attributes and improved texture defined by lower hardness and chewiness (both sensory and instrumental) and higher crumbliness. Sausages with DAGs showed a similar behavior to that of BF, so they could be a good alternative to produce healthier reduced fat non-acid fermented sausages.     

Effect of vaccination against gonadotrophin-releasing factor on growth performance, carcass, meat and fat quality of male Duroc pigs for dry-cured ham production

The aim of this study was to compare production, carcass and meat quality parameters, boar taint compounds and fat composition of green and dry-cured hams, between immunocastrated (IM), surgically castrated (CM) and female (FE) Duroc purebred pigs (n=75, 138.7±8.27kg). Liveweight and fat and muscle thicknesses were measured and average daily gain was calculated during growth. Carcass, meat and fat quality parameters were measured. Immunocastrated grew faster than CM or FE after the second dose of vaccine. IM had the lowest dressing percentage but similar % of ham and carcass lean to FE and CM. The effect of the immunocastration on carcass fatness depended on the location, did not affect fat and meat quality and reduced skatole and androstenone levels. Both in green and dry-cured ham, immunocastration slightly altered FA composition. Thus, Duroc pigs vaccinated with Improvac are suitable for the production of high quality dry-cured ham.     

The influence of pork quality traits and muscle fiber characteristics on the eating quality of pork from various breeds

The purpose of this study was to compare parameters associated with pork quality, muscle fiber, and eating quality among various breeds, and to examine if differences in eating quality were associated to pork quality and muscle fiber characteristics. For carcass and pork quality, although there were significant differences among breeds, the values of parameters in all pigs were assigned a normal quality class, a likely outcome of the similarity in the area percentage of type I and IIB fibers. For eating quality, pork loins from Berkshire pigs were more tender and full of pork flavor than Landrace and Yorkshire pigs. Except juiciness and mouth coating, over 20% of the variability in the eating quality parameters can be explained by pork quality traits and muscle fiber characteristics using multiple regression analysis. Furthermore, differences in muscle pH_24 h, cooking loss, shear force, and NPPC marbling score could explain a large proportion of variation in eating quality parameters associated with the texture of pork.     

Simplex lattice mixture design approach on the rheological behavior of glucomannan based salep-honey drink mixtures: An optimization study based on the sensory properties

The rheological properties of salep drink sweetened with different honeys were measured using a controlled-stress rheometer. Mixture design experiments were used to study the effect of interactions among pine, flower and highland honeys on the rheological properties of salep-honey drink mixture (SHDM) samples. In addition, product optimization was carried out using the ridge analysis to determine the optimum mixture proportions based on sensory properties of SHDM samples. Flower honey was the component showing the highest effect on the consistency coefficient values of SHDM samples. The preference of panelists was more prominent for the SHDM samples including the higher concentrations of highland honey with respect to odour and overall preference parameters. Optimum values of pine, flower and highland honeys in the mixture were found to be 0–85%, 0–40% and 15–100%, respectively, with respect to sensory properties. In addition, ridge analysis results revealed that the SHDM should include 65% highland honey, 35% pine honey and no flower honey to obtain the maximum overall preference score (7.24). The consistency coefficient and flow behavior index values of the sample to get maximum overall preference score (7.24) were predicted to be 3.650 Pa sⁿ and 0.435, respectively.     

Prediction of lamb meat eating quality in two divergent breeds using various live animal and carcass measurements

This study investigated how accurately taste panel sensory assessments of meat eating quality (MEQ) could be predicted in two divergent lamb breeds, using predictors measured in live animals (weights, subjective conformation assessments, ultrasound, computed tomography (CT) and video image analysis measurements) and carcasses (weights, MLC fat and conformation classes, pH, temperature, carcass dimensions and cross-sectional tissue dimensions), individually and in optimal combinations. Grilled muscle samples from the pelvic limb (semimembranosus) and loin (Longissimus lumborum) of 120 Texel (TEX) and 112 Scottish Blackface (SBF) lambs were assessed by a trained taste panel for texture, juiciness, flavour, abnormal flavour and overall liking. Residual correlations (adjusted for fixed effects, age and sire) between MEQ and predictor traits were low to moderate in size (<±0.42). MEQ traits predicted best by single measurements were loin flavour and overall liking for TEX (using fat area in a CT scan or subcutaneous fat depth measured post-mortem), and for SBF were leg texture (using carcass weight or temperature) and juiciness (using CT fat area or shoulder conformation score). Combining live animal and carcass measurements increased MEQ prediction accuracies, compared with using either set alone, to explain >40% of residual variation in several MEQ traits, with the highest adjusted R² values for leg juiciness in TEX (0.53) and leg texture in SBF (0.59). The most useful predictors of MEQ depended on breed, with measurements of fatness generally more important in the lean breed and carcass size and muscling more important in the fatter breed.     

Modelling the yield and texture of comminuted pork products using color and temperature. Effect of fat/lean ratio and starch

Practices to control the processing of finely comminuted meat products are proposed. The objective was to test the practical value of both temperature and light reflection measurements made during emulsification as potential indicators of cooking losses and resulting gel texture in pork sausages emulsified within a wide range of temperatures and starch and fat levels. Prior to cooking, pork batters were chopped for different times to ensure final emulsion temperatures ranging from 5 to 50°C. The effects of the fat/lean ratio (0.25 and 0.67) and starch addition (0.8 and 3.2% w:w) on temperature and optical reflection were also investigated. The chopping increased the temperature and decreased the light reflection of fresh meat emulsion. There was no relevant loss of emulsifying capacity at emulsion temperature below 30°C and lightness values over 70 CIE units. The losses and textural parameters of cooked emulsions could be predicted by means of non-linear regression equations based on the temperature and color of the raw emulsion. The determination coefficients obtained ranged from 0.89 to 0.99. The prediction models needed to be fitted to each batter formulation, especially in the presence of reduced levels of gelation agents (meat protein and starch). Lightness was a better predictor than chromaticity, since it decreased constantly with chopping in the range of final emulsion temperatures studied (5-50°C). This confirms previous studies that lightness could be used for monitoring emulsion stability in meat batters.     

The influence of breed and mh-genotype on carcass conformation, meat physico-chemical characteristics, and the fatty acid profile of muscle from yearling bulls

The influence of breed and mh-genotype on carcass conformation, meat physico-chemical characteristics and the fatty acid profile of muscle were studied. Samples from 16 yearling bulls from “Asturiana de los Valles” (AV, n = 12) and “Asturiana de la Montaña” (AM, n = 4) were collected. AV animals were classified into three groups according to the presence of the gene causing double-muscling (AV double-muscled (mh/mh), n = 4; AV heterozygous (mh/+), n = 4; AV normal (+/+), n = 4). Double-muscled animals displayed better carcass traits, lower total fat (comprised of subcutaneous (SC), intermuscular (IT) and intramuscular (IM) deposits), higher lean, moisture and drip loss, and lighter meat than AV normal animals. Heterozygous animals showed intermediate characteristics. AM animals, being a more rustic and smaller breed, showed lower conformation, higher total fat (SC, IT and IM), lower moisture and darker meat. According to the intramuscular fatty acid profile, mh/mh animals showed a lower proportion of SFA and MUFA, and a higher proportion of PUFA with an equal proportion of CLA in total fatty acid content. The P/S ratio increased with increasing number of mh alleles (or double-muscling character), while no differences between animal groups were found for the n − 6/n − 3 ratio.     

The influence of oral phenotypic markers and fat perception on fat intake during a breakfast buffet and in a 4-day food record

The ability to discriminate among foods with different fat contents has been associated with preference for high-fat foods and total fat intake. Consequently, oral phenotypic markers that influence fat perception may influence food selection and fat intake. The aim of this study was to investigate how the fungiform papilla (FP) count on the tongue tip, 6-n-propylthiouracil (PROP) bitterness, saliva flow, the increase in salivary flow via oil stimulation and the ability to perceive fat influence fat intake and food selection. A total of 107 subjects (80 female, 27 male) completed a 4-day self-administered food record before they rated the fat contents of different milk–cream mixtures and a high-fat emulsion. Of these subjects, 103 (76 female, 27 male) participated in an ad libitum breakfast buffet that was offered at the university cafeteria. The results show that the perception of the fat content of cream with 30.0% fat was associated with energy intake from fat and discretionary fats over 4 days and during the breakfast buffet. Subjects with lower FP counts ate relatively more high fat milk and spreads and as a consequence more fat during the breakfast buffet than subjects with high FP counts. The increase in salivary flow via oil stimulation was positively correlated with the reported intakes of discretionary and total fat over 4 days. These results support the hypothesis that FP count and the intensity perception of supra-threshold differences in fat content might play an important role in the selection of high-fat foods and fat intake.     

Simplex lattice mixture design approach on physicochemical and sensory properties of wheat chips enriched with different legume flours: An optimization study based on sensory properties

In this study, physicochemical and sensory characteristics of wheat chips enriched with different legume flours were investigated. Wheat chips formulations were composed with the mixture of wheat flour and the mixture of three different legume flours (wheat–legume ratio 80:20). Mixture design approach was used to determine the effect of interactions between pea, chickpea and soy flour on the physicochemical and sensory properties of chips produced with wheat–legume flour mixture. In addition, product optimization was carried out by using ridge analysis to determine the optimum legume flour mixture proportions based on sensory properties of chips samples. Chickpea flour was found to be highest desired component depending on the general acceptability scores of chips. Protein content of chips increased significantly with the addition of soy flour. Optimum limit values of chickpea, pea and soy flour in the legume flour mixture used for the enrichment of the wheat chips were found to be 50–100 g/100 g, 0–60 g/100 g and 0–45 g/100 g legume flour, respectively, with respect to sensory properties. Additionally, ridge analysis results showed that the wheat chips should include only chickpea flour in the legume flour fraction to obtain maximum overall preference score (6.08).     

Performance of a resistant starch rich ingredient in the baking and eating quality of short-dough biscuits

The effect of replacing part of the wheat flour with a resistant starch rich ingredient (RSRI) − a source of functional fibre with potential health benefits − was studied in short dough biscuits. A control with no replacement and 3 formulations in which 20, 40 and 60g of flour per 100 g were replaced by an RSRI (samples 20RSRI, 40RSRI and 60RSRI) were prepared. From a technological point of view, the RSRI level influenced the consistency of the raw dough and the ease of sheeting and cutting. Regarding the eating quality of the final product, addition of the RSRI increased the breaking strength and crumbliness and reduced the resistance to penetration. In the RSRI biscuits, both the surface and the crumb were paler. The sensory acceptance of the 20RSRI biscuits did not differ significantly from that of the control. 40RSRI reduced the acceptability of the colour, appearance and texture without altering the taste, sweetness and overall acceptance. Neither of these two levels significantly reduced the consumption intention. However, 60% flour replacement produced biscuits with lower sensory acceptability and a significant reduction in consumption intention. In general, the results could be interpreted in terms of the protein-diluting effect of the added ingredient and changes in the water content and water-retention capacity of flour mixtures containing RSRI. The present results proved that resistant starch rich ingredients (RSRI) have good potential for developing fibre-rich biscuits without changing their general features.     

Effects of inulin and sugar levels on the viability of yogurt and probiotic bacteria and the physical and sensory characteristics in probiotic ice-cream

Ice-cream containing probiotic bacteria was produced by mixing fortified milk fermented with probiotic strains with ice-cream mixes with different sugar concentrations (15, 18, 21% (w/w)). Cultures were grown (37 °C, 12 h) in UHT skimmed milk supplemented with or without inulin addition (1% and 2%). The fermented milk was added to the ice-cream mix to a level of 10% w/w.     

The effect of using a whey protein fat replacer on textural and sensory characteristics of low-fat vanilla ice cream

The purpose of this research was to evaluate the texture of regular (12%), low fat (6%), and fat-free vanilla (0.5%) ice creams by sensory and instrumental analyses. The low fat and fat free ice cream were prepared using a whey protein based fat replacer (Simplesse ^® 100) as the fat replacement ingredient. Two processing trials with continuous commercial-like process conditions were undertaken. Sensory analyses disclosed that ice creams containing 6% of fat replacer in place of or with milk fat had no demonstrable effect on vanillin flavour. While the sensory attributes of the low fat samples were comparable to the regular vanilla ice cream, the trained sensory panel rated the fat free ice cream to have lower viscosity, smoothness and mouth coating properties. Instrumentally determined apparent viscosity data supported the sensory data. Compared with the fat replacer, milk fat significantly increased the fresh milk and cream flavours of the ice cream. Results emphasized the importance of fat as a flavour modifier and the improvement of texture by addition of Simplesse ^® 100.