Manufacture Of Meat Products Research Articles

Effect of Iberian × Duroc genotype on dry-cured loin quality

Dry-cured loins from three different pig genotypes were studied: GEN1: ♂ Iberian × ♀ Duroc1, GEN2: ♂ Duroc1 × ♀ Iberian; GEN3: ♂ Duroc2 × ♀ Iberian. GEN1 and GEN2 are reciprocal crosses, while the difference between GEN2 and GEN3 is the Duroc sire line. The genotype of pigs Duroc1 was selected for the manufacture of dry-cured meat products, while the genotype Duroc2 was selected for meat production. The chemical composition of the dry-cured loins was significantly different, especially the intramuscular fat (IMF) content which was highest in GEN2. Dry-cured loins from GEN3 showed lower CIE a ∗ and chroma values. IMF from GEN2 was more saturated whereas GEN3 had higher percentages of PUFA and MUFA. Loins from GEN3 had higher TBA-RS values ( p > 0.05) and hexanal contents. Loins from GEN3 had higher Warner–Bratzler shear force ( p > 0.05) and instrumental hardness than those from GEN2, being intermediate in GEN1. Panellists considered that loins from GEN2 were more marbled, more odorous, juicier, sweeter and less salty than loins from GEN3. Therefore, loins from GEN2 had the best quality, followed by GEN1, while GEN3 had the worst quality.

Carcass composition and meat quality of three different Iberian × Duroc genotype pigs

Carcass composition and meat quality of Longissimus dorsi (LD) and Biceps femoris (BF) muscles from three different Iberian × Duroc genotype pigs were studied: GEN1: ♂ Iberian × ♀ Duroc1; GEN2: ♂ Duroc1 × ♀ Iberian; GEN3: ♂ Duroc2 × ♀ Iberian. Duroc1 (DU1) were selected for the manufacture of dry-cured meat products while Duroc2 (DU2) were pigs selected for meat production, with high percentages of meat cuts and low carcass fat. Genotype had a significant effect on the differences found while sex had not. GEN2 showed the highest weights at days 180 and 238 of weaning and the highest slaughter weights (day 316) followed by GEN3, while the lowest weights were found in GEN1. GEN3 had well conformed carcasses in comparison with GEN1 and GEN2, since GEN3 showed the highest percentages of ham and loin and the highest weight of loin as well as the lowest back and ham fat thickness. However, the use of DU2 pigs in the cross with Iberian had negative effects on meat quality, as GEN3 gave the worst meat quality in both muscles, postmortem pH, cook and drip loss, and colour and the lowest percentages of intramuscular fat (IMF). In subcutaneous fat (SCF), GEN3 had higher percentages of polyunsaturated fatty acids (PUFA) than GEN2, while GEN2 had higher saturated fatty acids (SFA) levels. In LD, IMF from GEN3 showed the highest percentage of MUFA and PUFA; while the fatty acid profile of GEN2 was more saturated. BF muscle showed similar trends, but not significantly so. On the other hand, few differences were found between reciprocal crosses (GEN1 vs. GEN2). GEN2 showed higher IMF in LD than GEN1, agreeing with their carcass weight. As a result, GEN1 had a fatty acid profile of IMF in the LD that was more unsaturated.

A survey of the dielectric properties of meats and ingredients used in meat product manufacture

The objective of the present study was to improve understanding of interactions between microwave (MW) and radio frequency (RF) radiation and meat/meat products. Dielectric properties at 27.12, 915 and 2450 MHz of lean, fat, aqueous solutions/suspensions and meat blends of typical ingredients used in meat product manufacture were measured. In addition temperature rises of ingredient/meat blends were compared following RF or MW heating. Frequency affected dielectric properties as did composition, with fat having lower dielectric activity than lean. Dielectric properties at MW frequencies appeared more sensitive to composition changes. Ingredients could be subdivided into groups having either lower or higher dielectric activity than lean, with concentration influencing which group an ingredient fell into. When low and high dielectric activity ingredients were incorporated into lean meats dielectric properties did not correlate well with temperature rises indicating the importance of other factors in addition to dielectric properties in determining temperature rise.

A survey of dry-salted natural casings for the presence of Salmonella spp., Listeria monocytogenes and sulphite-reducing Clostridium spores

A monitoring study was performed for the presence of Salmonella spp., Listeria monocytogenes and sulphite-reducing Clostridium spores in (internationally) traded dry-salted natural hog and sheep casings. Two hundred and fourteen consignments were examined for Salmonella spp. and L. monocytogenes, and 138 for the Clostridium spores.None of the 214 sampled consignments (25g amounts investigated) yielded Salmonella spp., or L. monocytogenes.Differential reinforced clostridial medium was effective in detecting the presence of sulphite-reducing clostridia. Iron sulphite agar (ISA) overall showed higher clostridia counts as compared to differential reinforced clostridial agar (DRCA). The maximum spore counts obtained on DRCA and ISA were 17.5 and 2500cfug−1, respectively. From the casings from China, 3 (of 35 hog consignments) and 7 (of 22 sheep) showed spore counts above 100cfug−1. From the remaining 81 samples, originating from Netherlands, New Zealand and UK, none showed a count above 100cfug−1.The relevance of the presence of sulphite-reducing Clostridium spores for the manufacture of various meat products is discussed. It is recommended that determination of the Clostridium strains present is carried out and their properties investigated in relation to the manufacture of meat products, since some of the strains may be potentially pathogenic and/or able to spoil products.

Effect of Chemically Modified Soy Proteins and Ficin‐tenderized Meat on the Quality Attributes of Sausage

ABSTRACT: The purpose of this investigation was to use ficin‐tenderized meat and cysteine‐modified soy proteins in the production of bologna and to evaluate the effect of these modifications on water‐holding capacity (WHC), emulsion stability (ES), texture, and protein solubility. The effect of ficin on meat protein was also evaluated by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE). Results indicated that both ficin‐tenderized meat and modified soy proteins substantially improved WHC, ES, and other quality factors. SDS‐PAGE results showed the disappearance of several protein bands in ficin‐treated meat. Solubility of meat proteins increased when ficin was used for meat tenderization. The results of this study indicated that some quality attributes of meat products can be improved by enzymatic and chemical modification of protein sources in the manufacture of meat products.

New mild technologies in meat processing: high pressure as a model technology

As a consequence of market globalization, the production and manufacture of meat products is at a stage of innovative dynamics. Consumers demand high quality and convenient meat products, with natural flavour and taste, and very much appreciate the fresh appearance of minimally processed food. To harmonize or to blend all these demands without compromising safety, it is necessary to implement new preservation technologies in the meat industry and in the food industry in general. High hydrostatic pressure (HHP) represents an attractive non-thermal process for meat products to avoid post-processing contamination. When combined with antimicrobials, like bacteriocins, the death rate may be increased because of sublethal injuries to living cells. HPP is a powerful tool to control risks associated with Salmonella spp. and Listeria monocytogenes in raw or marinated meats. The HPP treatment could extend the shelf life of the marinated beef loin by controlling the growth of both spoilage and pathogenic bacteria. As a general conclusion it can be stated that from both a physico-chemical and microbiological point of view, cooked pork ham, dry cured pork ham and marinated beef loin, vacuum-packed and high pressure treated at 600 MPa for 10 min at 30 °C, are substantially equivalent to the same untreated products.

Influence of Meat Processing and Meat Starter Microorganisms on the Degradation of Organochlorine Contaminants

The influence of processing of different dry-cured sausages on the degradation of organochlorine pesticide residues such as hexachlorobenzene (HCB), α-, β-, γ-hexachlorocyclohexane (HCH), and p,p'-DDE was investigated. The residual contamination was analyzed at different stages of the sausage's ripening by capillary gas-liquid chromatography with electron capture detector. Furthermore, the degradative capability of the microorganisms used as starters in the manufacture of such meat products (Pediococcus acidilactici, Pediococcus pentosaceus, and Micrococcus varians) was studied in vitro. The M. varians strain was able to degrade some of the compounds tested. Significant reductions (p 0.05).

Development of pilot-scale production of dry bacterial starter cultures for intensive manufacture of high quality meat products

Pilot-scale production of a dry starter culture of Lactobacillus and Micrococcus strains to produce sausage has been developed. A new procedure for preparing seed cultures and a mixed production culture is proposed to increase the viability of microorganisms and the shelf life. Pilot production tests of the developed preparation showed its high efficiency: 15–20% decrease in the period of meat fermentation and 5–7% increase in the yield of high-quality sausage.

Bacteriocins: modes of action and potentials in food preservation and control of food poisoning

Lactic acid bacteria (LAB) play an essential role in the majority of food fermentations, and a wide variety of strains are routinely employed as starter cultures in the manufacture of dairy, meat, vegetable and bakery products. One of the most important contributions of these microorganisms is the extended shelf life of the fermented product by comparison to that of the raw substrate. Growth of spoilage and pathogenic bacteria in these foods is inhibited due to competition for nutrients and the presence of starter-derived inhibitors such as lactic acid, hydrogen peroxide and bacteriocins (Ray and Daeschel, 1992). Bacteriocins, are a heterogenous group of anti-bacterial proteins that vary in spectrum of activity, mode of action, molecular weight, genetic origin and biochemical properties. Currently, artificial chemical preservatives are employed to limit the number of microorganisms capable of growing within foods, but increasing consumer awareness of potential health risks associated with some of these substances has led researchers to examine the possibility of using bacteriocins produced by LAB as biopreservatives. The major classes of bacteriocins produced by LAB include: (I) lantibiotics, (II) small heat stable peptides, (III) large heat labile proteins, and (IV) complex proteins whose activity requires the association of carbohydrate or lipid moieties (Klaenhammer, 1993). Significantly however, the inhibitory activity of these substances is confined to Gram-positive bacteria and inhibition of Gram-negatives by these bacteriocins has not been demonstrated, an observation which can be explained by a detailed analysis and comparison of the composition of Gram-positive and Gram-negative bacterial cell walls (Fig. 1). In both types the cytoplasmic membrane which forms the border between the cytoplasm and the external environment, is surrounded by a layer of peptidoglycan which is significantly thinner in Gram-negative bacteria than in Gram-positive bacteria. Gram-negative bacteria possess an additional layer, the so-called outer membrane which is composed of phospholipids, proteins and lipopolysaccharides (LPS), and this membrane is impermeable to most molecules. Nevertheless, the presence of porins in this layer will allow the free diffusion of molecules with a molecular mass below 600 Da. The smallest bacteriocins produced by lactic acid bacteria are approximately 3 kDa and are thus too large to reach their target, the cytoplasmic membrane (Klaenhammer, 1993; Stiles and Hastings, 1991). However, Stevens et al. (1991) and Ray (1993) have demonstrated that Salmonella species and other Gram-negative bacteria become sensitive to nisin after exposure to treatments that change the permeability barrier properties of the outer membrane (see below). This review will focus on the mode of action of lantibiotics (class I) and class II LAB bacteriocins and their potentials in food preservation and control of food poisoning.

Maple Syrup as Carbohydrate Source in Dry Sausage Fermentation

ABSTRACTMaple syrup was substituted for the glucose‐sucrose component of a standard dry sausage formulation to assess its feasibility in fermented meat product manufacture. Sausage batters containing either type carbohydrate were inoculated with a mixed starter culture containing Lactobacillus plantarum, Pediococcus acidilactici and Micrococcus varians. Similar acidification patterns were observed in fermenting batters containing glucose‐sucrose mixtures or maple syrup, and processing yields were unaffected by carbohydrate type. However, instrumental texture measurements (shear and compression forces) revealed that sausage made with maple syrup was significantly firmer than the standard product (P≤0.05). Maple syrup could be used in the manufacture of novel fermented meat products.

RELATIONSHIPS BETWEEN BINDING QUALITY OF MEAT AND MYOFIBRILLAR PROTEINS: IV. Contribution of Native Tropomyosin and Actin in Myosin B to Rheological Properties of Heat Set Minced-Meat Gel.

The binding quality of the heat set gel increased when F-actin was present in an appropriate ratio to myosin A. It increased further when tropomyosin was added to the myosin A/F-actin model system. The water holding capacity was increased by tropomyosin only. Thus, the contribution of not only myosin A but also of native tropomyosin and actin should be controlled in sausage manufacture. The presence of 0.6 M NaCl or KCl in the sol was necessary to produce high binding quality and high water holding capacity of heated myosin B gels. NaCl is preferred because of the taste effect on the meat product. Heating temperature (65, 80, or 90°CC) affected the physical properties of heated myosin B gels. The water holding capacity and the maximum relaxation time decreased with increasing temperature. In the manufacture of meat products, the heating temperature should be selected in accordance with the desired properties in the finished product.

A Modified Babcock Procedure for Rapid Determination of Fat in Meats Using Dimethyl Sulfoxide

Abstract A rapid method of determining fat in a wide variety of meat products has been developed. The meat is digested with hot HO and the products of the hydrolysis are dissolved in dimethyl sulfoxide; neutral triglycerides are insoluble in this solvent. The solubility of starches, sugars, and the usual curing inorganics in dimethyl sulfoxide and its miscibility with water prevent interference by these substances. Digestions are rapid, and phase separation and demarcation are excellent. One analysis (exclusive of sample preparation time) takes approximately 10 minutes. Only two reagents must be purchased, and no special equipment other than the usual Babcock apparatus is needed. Results by the sulfoxide procedure approximate results by the Mojonnier method. Its speed and simplicity should make it valuable for process monitoring and formulation adjustment in the manufacture of meat products.

Influence of Different Levels of Fat and Protein in Broiler Rations on Live Weight, Dressing Percentage and Specific Gravity of Carcasses

McNally and Spicknall (1950) reported a linear relationship between the specific gravity and fat content of broiler legs. Dansky and Hill (1952) indicated that birds fed a high energy ration deposited more fat on the carcass than did birds on a ration of moderate amount of energy content.Information on the effect of feeding different levels of fat and protein in broiler rations on dressing percentages and fat deposition of the carcass is lacking. Greater fat deposition which results from feeding high energy rations could prove to be of economic importance to poultry processors and manufacturers of poultry meat products because of lower dressing yields and greater cooking loss of the carcass.To determine the influence of different levels of added fat (bleached tallow2) and protein in broiler diets on these factors, 15 different rations formulated to give C:P ratios ranging from 35.7 to 50.1 were fed to broilers from…

Bacteriological standards for perishable foods. Manufactured meats.

The unrestricted growth of micro-organisms in meat products leads to spoilage and therefore it is necessary to consider whether meat products should be made to conform to microbial. standards. This question raises many problems which can be solved only in the distant future. However, an understanding of the rôle of micro-organisms in the manufacture of meat products suggests that in the immediate future it is possible to effect a considerable improvement in micro-biological quality. In order to achieve this result, education and advisory services will play an important part. It is important that pathogenic bacteria should be excluded from meat products, but it must be appre ciated that this problem concerns only a few of the micro-organisms which may adversely effect meat products. Furthermore, it is difficult to convince many of those concerned in food production that traditional methods should be improved if our arguments are related solely to the prevention of food-poisoning. The opinions expressed in this paper are those of the author and are not necessarily those of the Ministry of Food.