Effect of hazelnut skin and dry tomato peel on the oxidative stability, chemical and sensory properties of pork burgers during refrigerated storage

The quality deterioration of meat products due to lipid oxidation could be controlled by utilizing agri-food byproducts rich in antioxidants. This study evaluated the effect of adding hazelnut skin and dry tomato peel to pork burgers against oxidation phenomena. Three types of burgers were prepared: a control (C) with a basic formulation, and two formulations with 2.5% hazelnut skin (HS) or with 2.5% dry tomato peel (DTP). Microbiological, sensorial, and physio-chemical analyses were performed during 7 days of refrigerated storage (0–4 ◦C). Results showed a high inhibition of oxidation in HS burgers at all sampling times, both raw and cooked burgers, while in DTP burgers this phenomenon occurred only when cooked. Both by-products provided a significant amount of fiber, increased the polyunsaturated fatty acids (PUFA) content, and improved the omega-6/ omega-3 ratio

Effect of different stunning methods of pigs on subcutaneous veining defect and meat quality of raw ham

Trecentocinque suini pesanti sono stati sottoposti a stordimento elettrico (146 soggetti) o con CO2 (159 soggetti) per valutare l’effetto del metodo di stordimento sull’incidenza del difetto di venatura delle cosce, sul valore del pH, sul colore dei muscoli SM e BF e su alcuni parametri ematici. Nei suini sottoposti a stordimento con CO2 si è osservata una più alta percentuale di cosce con il difetto di venatura e valori più elevati di HCT, PT e PTT. I suini storditi mediante elettronarcosi hanno presentato un pH1 più basso e un colore più chiaro nel SM

Effects of dietary level of pantothenic acid and sex on carcass, meat quality traits and fatty acid composition of thigh subcutaneous adipose tissue in Italian heavy pigs.

Two trials were carried out to evaluate the effects of i) supranutritional doses of pantothenic acid (PA) and ii) sex on carcass, meat quality and fatty acid (FA) composition of subcutaneous adipose tissue in Italian heavy pig. In trial 1, 59 Duroc x (LxLW) pigs were fed the same diet containing either 10 [in the control (C) group] or 110 ppm [in the treatment (T) group] PA, from 107 to 168 kg live weight. At slaughtering, forty carcasses were sampled randomly. The T carcasses had lower backfat thickness (P<0.05), lower incidence of adipose cuts (P<0.05), higher lean cuts percentage (63.09 vs 60.64%; P<0.01) and lean meat yield (P<0.07). In trial 2, 42 pigs [Dumeco Cofok x (LxLW)], evenly divided into three groups, were fed the same feed containing respectively 10 (C), 60 (T1) and 110 ppm (T2) PA, from 95 to 165 kg live weight. The treatment lowered total adipose cuts yield (P<0.05) and increased lean/adipose cuts ratio (P<0.07). In the outer layer of thighs subcutaneous adipose tissue, the treatment raised polyunsaturated FA content (P<0.01), unsaturation coefficient (P<0.01) and polyunsaturated/saturated (P/S) FA ratio (P<0.05). In the inner layer, the treatment led to a lower saturated FA (P<0.05) and higher polyunsaturated FA content (P<0.01). In both trials, females generally provided leaner carcasses. In neither trials, vitamin level affected meat quality. Thus, feeding high levels of PA to heavy pigs can yield more valuable carcasses without affecting meat quality. However, effects on FA composition suggest caution in adopting this practice in the Italian heavy pig production

Natural complementary feeds in gestating and lactating sows: effects on performance and metabolic profile

Gestating and lactating sows were fed natural complementary feed with the aim to improve performance and metabolic profil

The use of thermography on the slaughter-line for the assessment of pork and raw ham quality

The left and right hams of forty heavy pig carcasses were thermographed to evaluate whether surface temperature differences were related to meat and ham quality. Thermal imaging analysis showed no differences in average surface temperature among classes of pH or of L* colour co-ordinate nor among classes of ham defects such as veining and red skin. However, hams with a lower fat cover displayed a significantly warmer average temperature surface. Infrared thermography seems to be a practical and non-invasive method to detect hamswith a fat cover below the minimum requested to be submitted to the dry-curing process

Shelf life of pork from five different quality classes

A total of 117 loins were selected on the cutting line at 24 h post-mortem to study the long term shelf life (35 days, 4 °C) of vacuum packaged pork from five different quality classes (PSE: pale, soft, exudative; PFN: pale, firm, non-exudative; RSE: red, soft, exudative; RFN: red, firm, non-exudative; and DFD: dark, firm, dry). The microbial load at 0 d was not significantly different (P > 0.05) among the pork quality classes, indicating that the initial microflora was influenced by the dressing conditions at the plant, not by the meat quality class. But after 35 d of storage, total aerobic mesophilic and presumptive lactic acid bacteria counts were higher (P < 0.05) in DFD pork due to its higher ultimate pH. RSE was the second quality class most susceptible to spoilage, whereas PFN, RFN and PSE pork had similar microbial loads. Further research is needed to elucidate the causes of the shorter shelf life in RSE pork

Effect of two sous-vide cooking methods on physicochemical characteristics of Longissimus thoracis muscle from pigs fed with or without extruded linseed

Meat is recognised as a highly nutritive food. With cooking, the meat enhances its nutritional value and becomes more digestible. However, high cooking temperatures lead to several chemical modifications in meat. Therefore, there is an increasing interest in sous-vide cooking. The aim of this research was to study the influence of two sous-vide cooking methods on physicochemical characteristics of Longissimus thoracis (LT) muscle from 24 pigs fed with two different diets: control group (C) had a basal barley/ soybean diet; in the linseed group (L), 5% of extruded linseed replaced the same amount of barley. At 24 h post mortem, LT muscles were sliced, vacuum sealed and stored at −18 °C until analysis. Samples were cooked in water bath at two different combinations of temperature and time: ‘A’ 80 °C of the bath water as long as the core temperature of the pork reached 70 °C; ‘B’ 60 °C for 15 h. After the cooking process, the samples were kept under refrigeration (2 °C) for 24 h. The day after, cooking loss, colour, pH, microbial growth and tenderness were determined. Microbial growth was analysed also in the raw meat. Statistical analysis was performed by means of ANOVA, using the GLM procedure of SAS. Dietary treatment (C vs. L) and cooking condition (A vs. B) were used as independent variables. Dietary treatments did not produce significant differences in pH, colour, cooking loss and tenderness. Colour parameters were affected by cooking method: a* values of the internal part of the sample and b* values of the external part were higher for the samples cooked at 60 °C (a* 4.74 vs. 3.97 for B and A, respectively, p&lt;.05; b* 17.79 vs. 15.84, p&lt;.01). The A cooking method led to higher (p&lt;.01) shear force values (5.03 vs. 3.30 kg). The microbial load in the raw meat was significantly different (p&lt;.05) between dietary treatments: C group showed higher total viable count (4.56 vs. 4.14 log10) and Enterobacteriaceae (2.65 vs. 1.94 log10) respect to L group. Low microbial growth was detected for both cooking methods. Total viable count was 0.50 log10 for A cooking method and 0.64 log10 for B, without significant differences among them. No Enterobacteriaceae growth was detected. Also, no differences were found for pH and cooking loss between A and B. Both cooking methods generated a meat safe from contamination. The B method: low temperature for long time also, generated tender meat

Functional analysis finds differences on the muscle transcriptome of pigs fed an n-3 PUFA-enriched diet with or without antioxidant supplementations

Supplementing pig diets with n-3 polyunsaturated fatty acids (n-3 PUFA) may produce meat products with an increased n-3 fatty acid content, and the combined antioxidants addition could prevent lipid oxidation in the feed. However, to date, the effects of these bioactive compounds at the molecular level in porcine skeletal muscle are mostly unknown. This study aimed to analyse changes in the Longissimus thoracis transcriptome of 35 pigs fed three diets supplemented with: linseed (L); linseed, vitamin E and Selenium (LES) or linseed and plant-derived polyphenols (LPE). Pigs were reared from 80.8 \ub1 5.6 kg to 151.8 \ub1 9.9 kg. After slaughter, RNA-Seq was performed and 1182 differentially expressed genes (DEGs) were submitted to functional analysis. The L vs LES comparison did not show differences, while L vs LPE showed 1102 DEGs and LES vs LPE 80 DEGs. LPE compared to the other groups showed the highest number of up-regulated genes involved in preserving muscle metabolism and structure. Results enlighten that the combined supplementation of bioactive lipids (n-3 PUFA from linseed) with plant extracts as a source of polyphenols increases, compared to the only addition of linseed, the expression of genes involved in mRNA metabolic processes and transcriptional regulation, glucose uptake and, finally, in supporting muscle development and physiology. These results improve the knowledge of the biological effect of bioactive compounds in Longissimus thoracis muscle, and sustain the growing interest over their use in pig production