Key factors such as stage of lactation, parity and body fat reserves have been associated with the digital cushion thickness, however, there are discrepancies between the results of previously ...published studies. The objective of this study was to examine the association of stage of lactation, body fat reserves, parity, and lesion incidence with the digital cushion thickness (DCT) in a large cohort of intensively monitored cows. Across 4 UK farms, 2,352 cows were prospectively enrolled and assessed at 4 time points; before calving (T1-Precalving), immediately post-calving (T2-Calving), in early lactation (T3-Early) and late lactation (T4-Late). At each time point body condition score was recorded, the presence of sole lesions (sole ulcers and sole hemorrhage) and white line lesions were assessed by veterinarians, and an ultrasound image was taken to retrospectively measure the back-fat thickness in the pelvic (BFT) region and the digital cushion on the hind left lateral claw. Mixed effects multivariable linear regression models, with the cow as a random effect were fit to examine the association between explanatory variables and the DCT. Explanatory variables tested were farm, parity, stage of lactation, body condition score, BFT, height, the presence of a lesion at the time of measurement, the chronicity of a lesion during early lactation, predicted maximum daily milk yield and the rate of milk production rise in early lactation. Stage of lactation and farm were both associated with the DCT, however an interaction was present and this DCT pattern of change was farm dependent. Two distinct patterns emerged; one indicated the nadir to occur shortly after calving, the other indicated the nadir to occur during early lactation. Neither back fat thickness nor BCS were significantly associated with the DCT. Heifers displayed thinner digital cushions compared with multiparous cows, however, this effect was dependent on the stage of lactation, with heifers having a thinner digital cushion up until late lactation, by which time the DCT was commensurate with multiparous animals. Sole lesions and white line lesions at the time of measurement were associated with the DCT (sole lesion; Estimate: −0.07mm, 95% CI: −0.14–0.00, P = 0.039, white line lesion; Estimate: 0.28mm, 95% CI: 0.15–0.42, P < 0.001).
This study aimed to investigate the effect of canola oil-emulsion gels (EGs) stabilized by pork skin and dietary fibers to replace the total content of pork back fat in emulsified meat products. A ...Plackett-Burman (PB) design was carried out to select the best ingredients (pork skin gel (PSG), inulin, polydextrose, α-cyclodextrin, and bamboo fiber) for the functional properties of the EGs. Three variables (PSG, inulin, and bamboo fiber) were select for the full factorial design to choose the best combination of ingredients for EGs enhancement. PSG, inulin, and bamboo fiber contributed to increasing the stability and the rupture stress of the EGs, the rupture strain of the EGs was increased only by PSG. Bamboo fiber was also associated with an increase in the meat emulsion stability. Besides, the meat emulsions incorporated with the EGs presented emulsion stability and pH very similar to those observed for meat emulsion made with pork back fat. These results show that EGs made with PSG and dietary fibers are an alternative ingredient to replace pork back fat in the manufacture of emulsified meat products, considering the nutritional aspects and the valorization of byproducts of the meat industry.
•Emulsion gels (EGs) based on pork skin, inulin, α-cyclodextrin, polydextrose, and bamboo fiber were elaborated.•Pork skin gel showed suitable emulsifying and gelling properties.•Bamboo fiber and α-cyclodextrin improved significantly the emulsion stability of the EGs based on pork skin.•Bamboo fiber and inulin raised the rupture stress of the EGs, and α-cyclodextrin made the EGs more brittle.•EGs exhibited similar behavior to that presented by pork back fat in the meat emulsion model systems.
The effect of partial substitution of pork backfat by olive oil oleogel and NaCl by KCl on the technological and nutritional characteristics of fermented sausages was studied. Four formulations of ...fermented sausages were evaluated: control (C) with 18g pork backfat and 1.5g NaCl per 100g; treatment (N) with 50% NaCl substituted by KCl; treatment (O) with 50% pork backfat substituted by oleogel; and treatment (D) with 50% simultaneous substitution of NaCl and pork backfat by KCl and oleogel. Selected physicochemical and microbiological characteristics of the formulations were measured on 0, 1, 4, 7 and 14 d after manufacture. Treatment (D) had higher water activity and exhibited lower weight loss. Sensory evaluation was performed by a nine-member trained panel and differences among treatments were identified in color and textural attributes, but not in flavor, bitterness, saltiness. According to a 54-member consumer panel, treatment (O) was judged as second best in personal preference, following treatment (C). After fermentation and ripening of the sausages, treatment (D) had 51.9% less sodium, 19.2% less cholesterol and 17.8% less saturated fatty acid content than (C). The results show that it is possible to produce sensorially acceptable and microbiologically safe fermented sausages with a healthier nutritional profile.
•Pork fat and NaCl were partially replaced by oleogel and KCl in fermented sausages.•The NaCl substitution did not affect the fermentation and ripening process.•Pork fat and NaCl substitution resulted in sensorially acceptable sausages.•The substitution of pork fat and NaCl improved the nutrient content of the sausages.
In this study, the effects of different microwave treatment times (10, 20, 30, 40, 50, and 60 s) on fat loss, fatty acid profile, lipid transfers, and microstructure of pork subcutaneous back fat ...(PSBF) were investigated. Results showed that the fat loss of PSBF after microwave treatment for 60 s was significantly increased (53.31%). Microwave treatment increased the proportion of saturated fatty acids but reduced the relative content of monounsaturated and polyunsaturated fatty acids. Cryo-scanning electron microscopy, ordinary optical microscope and confocal laser scanning microscope analysis demonstrated that microwave treatment facilitated a large outflow of fat from the adipocytes, and the increasing and then decreasing changes in the size of individual adipocytes. Magnetic resonance imaging enabled the visualization of fat migration of PSBF. Overall, PSBF can be used as a biological model to evaluate the effect of microwave treatment on the change and migration mechanism of fat.
•Microwave treatment (MW) decreased fat content of pork subcutaneous back fat.•Magnetic resonance image enabled visualizing fat migration during MW.•The size of individual adipocytes increased and then decreased after MW.•MW could produce meat products with high nutritional value and low-fat content.
Pork subcutaneous fat (PSF) is used for the development of several products, and the evaluation of the qualitative and quantitative characteristics currently involves lengthy procedures. In this ...study, the discriminant and predictive capability of near-infrared hyperspectral imaging were tested on PSFs, which were collected from the belly, ham, loin, and shoulder. The spectral information from the hyperspectral images was used to discriminate amongst these fats as well as predict their iodine values (degree of fat unsaturation) using partial least squares discriminant analysis (PLS-DA) and partial least squares regression (PLSR). The result showed that PLS-DA was outstanding in discriminating PSFs with classification error in the validation dataset ≤0.05%. For the IV, result for the IV measurement showed a good accuracy (R2p = 0.77 and RMSEP = 1.83-g I2/100g fat). This study showed that the hyperspectral imaging technique has the potential to discriminate PSFs from different locations of the pork carcass and also evaluate the IV.
•Hyperspectral images acquired from pork fats.•Extracted spectral information used to discriminate the pork fats.•Extracted spectral information used to calculate iodine value (IV).•PLS models were used as the modeling algorithms.•Hyperspectral imaging was outstanding for discrimination and IV assessment of fats.
The aim of this research was to prepare curdlan-based emulsion micro-gel particles with different concentration of the curdlan (0.5 g/100 mL, 1.0 g/100 mL, 1.5 g/100 mL, 2.0 g/100 mL, 2.5 g/100 mL), ...which respectively named as CEM(0.5), CEM(1.0), CEM(1.5), CEM(2.0), CEM(2.5). And the microstructural, rheological and texture properties of the emulsion micro-gel particles were investigated. Then, CEM(1.0) was used as a compound fat replacement in pork sausages and the effects of different replacement rates on the caloric value, texture and sensory quality of pork sausages were investigated. The results showed that the WPI and curdlan aggregation, the hardness, shear stress, the G′ and G″ moduli of the curdlan-based emulsion micro-gel particles significantly increased with increasing curdlan concentration. CEM(1.0) has the closest sensory quality to pork back fat and uniform inner structure. Digestion behaviors of CEM(1.0) showed that the curdlan gel network can not only delay the lipid digestion, but also inhibit the lipid digestion. The results showed that curdlan-based emulsion micro-gel particles can be used to replace 40% fat to produce low-fat pork sausages which had similar sensory acceptance with full-fat samples.
•The curdlan-based emulsion micro-gel particles (CEM) prepared by heat-shearing.•The influence of the curdlan concentration on the CEM was investigated.•CEM(1.0) could be selected as a replacement of pork back fat.•The curdlan gel network can delay and inhibit the lipid digestion.•CEM(1.0) can be used to replace 40% fat to produce low-fat pork sausages.
This work aimed at exploring the potential of partial substitution of the back-fat with fat mimetic, a novel polysaccharide-protein complex of xanthan gum and succinylated chicken liver protein, to ...improve the physicochemical characteristics and fatty acid composition of emulsified sausages. The quality characteristics of the sausages demonstrated that low-fat emulsified sausages with the addition of fat mimetic or its sunflower oil pre-emulsion presented similar microstructure and texture to high-fat sausages, while pre-emulsion increased the gel strength and whiteness of products. The rheological behavior characterization indicated that fat replacers caused a significant increase in storage modulus and loss modulus, explaining well the decreased cooking loss and the improved emulsification stability, water holding capacity (WHC) and heating stability. Although the back-fat replacement led to a great decrease in fatty acids, the nutritional values of fatty acids were optimized due to the incorporation of sunflower oil, as revealed by a 10% increase of polyunsaturated fatty acids and the decreased TBARS values within the storage. This study suggests the technological feasibility to simultaneously improve the quality and nutritional features of emulsified sausages with partial back-fat replacement by the proposed polysaccharide-protein complex, as well as the way to achieve chicken liver valorization.
•A novel polysaccharide-protein complex is proposed as fat replacer.•Chicken liver protein can be valorized as the fat mimetic.•Pre-emulsified sunflower oil is used to improve the fatty acid profile in sausages.•Fat substitutes strengthened the structural and rheological properties of sausages.•Fat substitutes decreased the TBARS values of sausages during storage.
We examined the changes in body weight (BW), back‐fat thickness (BFT) and blood metabolites in relation to postpartum (PP) ovarian activity status in twenty female yaks raised under semi‐intensive ...system. BFT and ovarian activities, like follicle development, ovulation (OV) and corpus luteum (CL) development, were monitored from 4 to 15 weeks (wk) PP using ultrasonography. Resumption of ovarian activity was confirmed with ovulation of dominant follicle (DF) and subsequent CL development, and >1 ng/ml progesterone concentration in blood plasma sample after 1week of ovulation. Yaks were further classified as cyclic (with CL), acyclic (without CL), and cystic (with >25 mm follicular cyst; FC). Within 20 weeks PP, 60% yaks resumed cyclic ovarian activity, while 25% failed to initiate cycling activity, and 15% developed follicular cysts. In all categories of yak, BW gradually decreased (p < .05) till nadir; however, nadir reached earlier (p < .05) in acyclic yaks. BFT differed (p < .05) among the yak groups, but it tended to be higher in cyclic yaks as compared to acyclic and cystic. No difference (p > .05) in non‐esterified fatty acids (NEFA) values was found among the different categories of yaks, whereas, beta‐hydroxy butyrate (BHB) levels were higher in cystic animals as compared to acyclic and cyclic. Blood glucose levels decreased in all yaks during initial 2 weeks after calving. Our findings suggest that yaks with low BW, BFT and glucose levels, and higher BHB values were at risk of delayed resumption of ovarian activity and concomitant development of follicular cysts.
•Pre-emulsifying back-fat and plant oil increased water- and fat-binding of liver paste batters.•Pre-emulsification and substituting above 20% back-fat decreased T21a, T21b and T22.•Added 20–40% ...plant oil combined with pre-emulsification decreased α-helix content.•Pre-emulsification and plant oil substitution changed Trp and Tyr hydrophobic residues.
Protein structural changes and water mobility properties in chicken liver paste batters prepared with plant oil (sunflower and canola oil combinations) substituting 0–40% pork back-fat combined with pre-emulsification were studied by Raman spectroscopy and low-field nuclear magnetic resonance (NMR). Results showed that pre-emulsifying back-fat and plant oil, including substituting higher than 20% back-fat with plant oil increased the water- and fat-binding (p<0.05) properties, formed more even and fine microstructures, and gradually decreased the NMR relaxation times (T21a, T21b and T22), which was related to the lower fluid losses in chicken liver paste batters. Raman spectroscopy revealed that compared with a control, there was a decrease (p<0.05) in α-helix content accompanied by an increase (p<0.05) in β-sheet structure when substituting 20–40% back-fat with plant oil combined with pre-emulsification. Pre-emulsification and plant oil substitution changed tryptophan and tyrosine doublet hydrophobic residues in chicken liver paste batters.
•A selective genotyping approach designed for pig backfat thickness was mined for other traits.•A few hundreds of single nucleotide polymorphisms (SNPs) were genotyped in Italian Large White ...gilts.•Random residuals (RRs) of six traits were used in the association analyses.•SNPs in EXOSC1 and PYGL genes were associated with ham weight loss at first salting.•TBC1D1 gene haplotypes were associated with performance, carcass and meat traits.
Italian heavy pig selection programs are based on production (average daily gain, ADG; feed gain ratio, FGR), carcass (weight of lean cuts, LC; ham weight, HW; backfat thickness, BFT) and meat quality traits of the green hams (ham weight loss at first salting, HWLFS; and visible intermuscular fat, VIF). In this study, we evaluated whether a selective genotyping approach previously designed for BFT could identify markers associated with other traits (ADG, FGR, HW, HWLFS, LC and VIF), most of which correlated with BFT. Italian Large White gilts were chosen according to their extreme estimated breeding values for BFT (275 with the most negative and 278 with the most positive EBVs) within a population of about 12,000 sib-tested pigs. A total of 736 single nucleotide polymorphisms (SNPs) in candidate genes for fat deposition and/or related traits were genotyped. After filtering, a total of 279 SNPs in 234 genes remained for association analyses that were carried out using random residuals (RRs) for the six mentioned traits. Four SNPs in three candidate genes were associated with some of the considered traits. A SNP in the exosome component 1 (EXOSC1) gene and a SNP in the glycogen phosphorylase L (PYGL) gene were associated with HWLFS RRs. Two SNPs within the TBC1 (tre-2/USP6, BUB2, cdc16) domain family, member 1 (TBC1D1) gene were associated with LC RRs and suggestively associated with other performance, carcass and meat traits. Association analysis using six TBC1D1 haplotypes, inferred from four genotyped SNPs within this gene, confirmed the results of the single-marker association study.
This study contributes to dissect the biological mechanisms underlying the genetic correlations among BFT, HWLFS and LC, which are critical for the sustainable implementation of tailored selection programs in heavy pigs.
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