M.D. Garrido

A comparative study of boar taint in cooked and dry-cured meat.

A comparative study of boar taint in cooked and dry-cured pig meat products was performed. Forty-eight cooked loins and 48 dry-cured hams from entire males and castrates were studied. The samples were classified according to the androstenone (AN) and skatole (SK) fat content determined using HPLC. A trained sensory panel evaluated taste, aroma, boar odour, boar flavour, juiciness, tenderness and fatness in cooked and dry-cured samples. Threshold levels of AN and SK to separate (P<0.05) entire and castrate samples according to their boar odour and flavour were determined. The effects of castration and processing on the eating quality were studied. Finally, the relationships among boar taint and other sensory attributes in cooked and dry-cured meat were compared. Results from these studies show that the eating quality of processed meat was affected negatively by boar taint. Threshold values were higher in dry-cured ham (2 μg g(-1) AN and 0.12 SK) than cooked loin (0.5 AN and 0.1 SK). AN and SK had a synergistic effect on boar odour and flavour in both products. AN had a greater influence than SK on the aroma and taste, especially in cooked meat. Boar odour was perceived more intensely than boar flavour in both of the products studied. Castration favoured fatness and improved the aroma and taste of cooked and dry-cured meat. The loss of aroma and taste due to boar taint was more noticeable in cooking than drying and curing. In dry-cured meat boar taint was associated with less aroma, taste, juiciness and tenderness. However, in cooked meat, boar taint affected the aroma and taste more strongly, but was not related with juiciness and tenderness, probably because these attributes are influenced by cooking.

Pre-cure freezing affects proteolysis in dry-cured hams

Several parameters (sodium chloride, moisture, intramuscular fat, total nitrogen, non-protein nitrogen, white precipitates, free tyrosine, L* a* b* values and acceptability) related with proteolysis during the curing were compared in dry-cured hams manufactured from refrigerated and frozen/thawed raw material. Pre-cure freezing increased the proteolysis levels significantly (p<0.05) in the zones of the ham where water losses and absorption of salt is slowest. Frozen hams present a high incidence of white precipitates, formed mainly by tyrosine crystals. The colour and acceptability scores are similar in frozen and refrigerated hams. The previous freezing and thawing process accentuates the water losses, salt absorption and proteolysis of the cured meat, although it does not significantly affect the sensory quality of the dry-cured ham.

Fresh and eating pork quality from entire versus castrate heavy males

Abstract Pork quality from entire (EM) and castrated (CM) male pigs slaughtered at 105 kg live weight was compared. Two commercial pig crossbreeds were studied: Cross D (Large White×Duroc females and Landrace×Duroc males) and Cross L (Landrace×Large White females and Large White males). Androstenone (AN), skatole (SK) and indole (IN) backfat levels, fresh meat quality (moisture, protein, intramuscular fat, drip and cooking losses, pH and colour) and eating quality by a trained panel (boar odour and flavour, juiciness, tenderness, aroma and taste of freshly cooked loin) and untrained consumers (preference and acceptance) were determined. Results from these studies show that 35% (25%: Cross D; 45%: Cross L) and 10% (5% and 15%) of EM had over 0.5 μg AN and 0.25 μg SK g −1 fat, respectively, the cut-off values to detect boar taint in meat. Castration increased meat fatness and reduced boar taint, the aroma and taste of freshly cooked meat was more appreciable, while its effects on juiciness and tenderness were less clear. Pork acceptance was better in CM than in EM. CM was preferred by 75% of consumers.

The effects of castration on the eating quality of dry-cured ham.

The influence of the castration of entire male pigs on the eating quality of dry-cured ham was evaluated. Forty-eight dry-cured hams (435-day aged) were studied from entire and castrated males of two different crossbreeds. The proximate composition of the meat and the androstenone, indole and skatole fat content were determined. The entire hams were classified according to the androstenone and skatole content. Sensory analysis was carried out by a trained panel, evaluating marbling, juiciness, saltiness, graininess, toughness, overall flavour, boar odour and boar flavour. Also carried out was a preference and acceptability paired test by consumers. Castration increased meat fattening and reduced the androstenone and skatole levels of the fat. Significant differences (P<0.05) were found between entires and castrates for the average values given in all the sensory attributes studied. The dry-cured ham from castrates was scored as more flavoured, more marbled and softer. It was also perceived as less grainy, less salty and having less boar odour and flavour. The sensory perception of boar odour was more intense than that of flavour in dry-cured ham and appears to be related to the level of androstenone and skatole in fat. Dry-cured ham from castrated males was also more accepted and more preferred by consumers, especially women and habitual consumers. Castration of male pigs contributes to improve the quality of dry-cured ham. The rejection caused by boar odour and flavour is reduced, improving the overall flavour, texture and juiciness. In addition, the saltiness is less pronounced in ham from castrates. For this reason, the production of high quality dry-cured ham will have to shoulder the extra costs associated with processing castrated pigs.

Objective assessment of pork quality

Several objective methods for estimating pork quality were studied: internal light scattering (FOP), electrical conductivity (EC), pH, colour, water holding capacity (WHC), soluble proteins (SP), pigment content, intramuscular fat (i.m. fat), and moisture. The measurements were made on the Semimembranosus and Longissimus thoracis at 45 min and 24 h post mortem in some cases and on the Semimembranosus in others. Most of the measurements are significantly different between normal, PSE and DFD quality categories. There is a good correlation between pH values in both muscles: pH(45)SM-pH(45)LT (r=0.74) and pH(24)SM-pH(24)LT (r=0.71). At 45 min the correlation of EC with FOP and pH was r=0.56 and r=0.48 respectively. Lower correlations were found in other parameters. The results from principal component analysis (PCA) showed that the three first components explained 60.3% of the total variation and the most important variables for the first PC were pH(45) and EC(45).

Crude glycerine inclusion in Limousin bull diets: animal performance, carcass characteristics and meat quality.

Three hundred and six Limousin young bulls (7±1months of age, initial body weight 273±43kg) were used to evaluate the effect of crude glycerine supplementation on animal performance, carcass characteristics and meat quality. Animals were assigned to three different diets: Control (0% of crude glycerine), G2 and G4 (2 and 4% of crude glycerine, respectively). The diets were administrated ad libitum for 240days (final body weight 644±24kg). Average daily weight gain, average daily feed intake, the gain:feed ratio, ultrasound measures in vivo, carcass characteristics, pH, water holding capacity, drip losses, and cooking losses were not affected (P>0.05) by diets. Diet decreased C16:0 (P<0.01) and C16:1 (P<0.05) contents in meat. The G4 meat showed lower C12:0, C14:0, C17:0, C18:0, C18:1, C18:2, C18:3, c9,t11-c18:2, C20:0 and C20:4 levels (P<0.05) than control. Glycerine increased desirable fatty acid percentages (P<0.05) in intramuscular fat.

Evaluation of different strategies to mask boar taint in cooked sausage

The use of smoking and/or spices was evaluated for their ability to mask boar taint in frankfurters manufactured from entire pigs with high levels of androstenone. Five frankfurter types were considered: control, smoked, flavouring+smoked, spicy and spicy+smoked. A trained panel in androstenone perception carried out a sensory profile on the different sausages. The highest scores for androstenone perception (odour, flavour and aftertaste) were found in frankfurters that included no masking strategy which indicated the effectiveness of the evaluated strategies. Regarding masking strategies, the contribution of spices and smoking to sensory perception of frankfurters was detected by the panellists. Smoking was the best strategy to mask androstenone odour, while the use of spices masked androstenone odour to a greater extent than androstenone flavour. Only the combined use of spices and smoking was able to eliminate the perception of androstenone. The application of this strategy in frankfurters could be an alternative in the commercialization of entire pigs.

Objective meat quality measurements of ham: A practical classification method on the slaughterline

Meat quality is one of the principal problems in Spanish dry cured ham productuon. At the experimental level, there are well developed objective instrumental measurements which can be made on the slaughterline and then, by applying the correct statistical treatment, these measurements can be used to classify hams with an acceptable degree of accuracy. These treatments, however, are not easy to apply in the industry. In this work, 312 pork carcasses were tested at three industrial abbatoirs. Ham meat quality was determined by internal light scattering (FOP), electrical conductivity (EC) and pH measurements in Semimembranosus (SM) muscle at 45 min and 24 h post mortem. The results obtained were: 21 (6.7%) DFD; 168 (53.9%) slightly DFD; 104 (33.3%) normal; 11 (3.5%) slightly PSE; and 8 (2.6%) PSE. A simplified method has been developed for classifying hams into quality categories, by deriving a theoretical quality value (Q) based on a simple statistical treatment of values for FOP, EC and pH. The multiple linear regression coefficient of Q was R(2) = 0.85 (P<0.001) with respect to the experimental variables.

TBARs distillation method: Revision to minimize the interference from yellow pigments in meat products

The aim was to study the effect of the incubation method and TBA reagent (concentration/solvent) on yellow pigment interference in meat products. Distillates from red sausage, sucrose, malondialdehyde and a mixture of sucrose-malondialdehyde were reacted with four different TBA solutions at five different temperature/time relations. Two TBA solutions were prepared at 20mM using 90% glacial acetic acid or 3.86% perchloric acid. In addition, an 80mM TBA solution was prepared using distilled water adjusted to pH4 and another using 0.8% TBA in distilled water. The temperature/time relations were: (1) 35min in a boiling water bath; (2) 70°C/30min; (3) 40°C/90min; (4) room temperature (r.t.) (24°C) in dark conditions for 20h; and (5) 60min in a boiling water bath. The results showed that aqueous or diluted acid solutions of TBA reagent and the application of 100°C for less than 1h provided the best conditions to minimize the presence of yellow pigments and maximize pink pigment formation in meat products.

Feeding Iberian × Duroc cross pigs with crude glycerine: Effects of diet and gender on carcass and meat quality

Ninety (45 castrated males and 45 gilts) Iberian × Duroc pigs were used in this study. During the finishing period (95-160 kg body weight, 74 days) animals received conventional feed (control G0) or the same feed plus 5% (G5) or 10% (G10) of crude glycerine to partially replace wheat. In general, neither the diet nor gender affected ultrasound, carcass or meat quality parameters. The G10 had lower values of cooking loss and a* than the G5 and G0 groups. The fatty acids, C10:0, C12:0 and C18:3, in intramuscular fat were lower in both glycerine groups. Polyunsaturated fatty acids and 18:2 decreased and C20:0 increased at the subcutaneous fat of G10 animals. Castrated males produced carcasses with higher backfat thickness and fat content. Castrated males had a higher SFA content in subcutaneous fat than females (P<0.001). In conclusion, up to 10% crude glycerine could be used in the Iberian × Duroc diet.