Development of strategies to manufacture low-salt meat products - a review.

Urbanization is usually followed by changes in eating habits, with a specific trend toward the consumption of ready-to-eat products, such as processed foods. Among the latter, meat products are known contributors to high dietary sodium owing to salt addition. Salt plays an essential role in maintaining the quality of meat products in terms of acceptability and safety. However, an excessive salt intake is linked to high blood pressure and cardiovascular diseases. Hence, several studies have been competing for the discovery of salt alternatives performing in a similar way as common salt. A number of replacements have been proposed to reduce salt consumption in meat products while taking into account consumer preferences. Unfortunately, these have resulted in poorer product quality, followed by new adverse effects on health. This review addresses these recent issues by illustrating some established approaches and providing insight into further challenges in developing low-salt meat products.

Optimal raw material formulation to produce pressed pork ham at the least cost.

This study optimized material use for making pressed pork hams (PPHs) using the least cost formulation program. Based on protein (P) content, different fat (2.5, 3.0, and 4.0P) and moisture (4.0P + 10, 4.0P + 15, 4.0P + 20, and 4.0P + 25) ratios were applied to make PPHs. Total expressible fluid, cooking loss, and purge loss were highest in PPHs formulated with 4.0P + 25 water (P < 0.05). With increasing fat ratio, lightness increased, but redness decreased (P < 0.05). Lipid oxidation was not affected by moisture ratio (P > 0.05). Hardness, gumminess, and adhesiveness decreased with increased fat and moisture (P < 0.05). PPH cost was reduced by fat and moisture. These results suggest that the formulations with 4.0P + 15 moisture, regardless of fat ratio, are recommended for PPHs due to their moderate cost and quality characteristics. In addition, greater cost savings can be expected by further subdividing raw material criteria for industrial applications.

Overview of Studies on the Use of Natural Antioxidative Materials in Meat Products.

Studies conducted in the past decade related to the use of natural antioxidants in meat products revealed the prevalent use of plant-based antioxidative materials added as powders, extracts, or dried or raw materials to meat products. The amount of antioxidative materials varied from 7.8 ppm to 19.8%. Extracts and powders were used in small amounts (ppm to grams) and large amounts (grams to >1%), respectively. Antioxidative materials used in meat products are mainly composed of phenolic compounds and flavonoids, which are able to inhibit lipid peroxidation of meat products, thereby preserving meat quality. However, the main ingredients used in processed meat products are the traditional additives, such as sodium erythorbate, sodium hydrosulfite, and synthetic antioxidants, rather than natural antioxidants. This difference could be attributed to changes in the sensory quality or characteristics of meat products using natural antioxidants. Therefore, novel research paradigms to develop meat products are needed, focusing on the multifunctional aspects of natural antioxidants.

Changes of various insecticides during in vitro human digestion.

This study was performed to determine the effects of in vitro human digestion on the concentrations of five insecticides, namely 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE), bifenthrin, and fipronil. In vitro models included all the steps of human digestion, i.e., passage through the mouth, stomach, small intestine, and large intestine (with enteric bacteria). The concentrations of DDT and fipronil did not change (P > 0.05) until small intestinal digestion, whereas those of DDD, DDE, and bifenthrin decreased (P < 0.05) at each digestion step. The concentrations of all the insecticides decreased (P < 0.05) during the large intestinal digestion step with enteric bacteria, Lactobacillus sakei and Escherichia coli. In conclusion, the concentrations of all the tested insecticides decreased during all the steps of in vitro human digestion and were especially reduced by enteric bacteria during the large intestinal digestion step.

Effects of Hemin and Heating Temperature on the Mutagenicity and Lipid Oxidation of Pork Batter during In Vitro Human Digestion with Enterobacteria.

The objective of this study was to determine the effects of hemin and heating temperature on the mutagenicity and lipid oxidation of pork batter during in vitro human digestion with enterobacteria. The mutagenicity and lipid oxidation of pork batter increased in the presence of hemin and with increasing temperatures from 60 to 80°C by 17.9 and 23.0% and by 54.6 and 21.2%, respectively. However, the pork batter mutagenicity decreased by 6.09% during in vitro human digestion, whereas lipid oxidation increased by 19.4%. The antioxidant activities of pork batter decreased with hemin and increasing temperature but gradually increased during in vitro human digestion, especially in the large intestine, regardless of the type of enterobacteria ( Escherichia coli and/or Lactobacillus sakei). These results indicate that hemin and temperature are closely related to mutagenicity in pork batter, and in vitro human digestion with enterobacteria could reduce mutagenicity possibly owing to the increase in antioxidant activity by antioxidative enzymes released by enterobacteria.

Effects of Six Different Starter Cultures on Mutagenicity and Biogenic Amine Concentrations in Fermented Sausages Treated with Vitamins C and E.

This study was performed to determine changes in mutagenicity and biogenic amine concentrations in sausages fermented with six different starter cultures treated with vitamins C and E. Six different types of fermented sausages with different combination of starter cultures were manufactured. T1, Pediococcus acidilactici; T2, P. pentosaceus and Staphylococcus carnosus; T3, S. carnosus, S. xylosus, Debaryomyces hansenii, Lactobacillus curvatus, and P. pentosaceus; T4, S. carnosus and L. sakei; T5, S. xylosus and L. plantarum; and T6, Penicillium nalgiovensis. After treatment with vitamins C and E in fermented sausages, changes in mutagenicity and biogenic amine concentrations were measured. The sausages fermented with Staphylococcus xylosus and Lactobacillus plantarum starter cultures showed the most effective antimutagenic activity (p<0.05). The mutagenicity was further decreased in the sausages treated with vitamins C and E (p<0.05), regardless of the starter cultures. The use of Pediococcus acidilactici, S. xylosus, L. plantarum, and Penicillium nalgiovensis as starter cultures was effective in decreasing biogenic amine concentrations (p<0.05). In addition, vitamin E was more effective in decreasing the biogenic amine concentrations than vitamin C. In conclusion, we recommend the use of S. xylosus and L. plantarum as starter cultures, in addition to the use of vitamins C and E, to reduce the potential risk of meat mutagens in fermented sausages.

Degradation of various insecticides in cooked eggs during in vitro human digestion.

The objective of this study was to determine the effects of cooking and in vitro human digestion on the changes of five insecticides-fipronil, bifenthrin, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), and 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE)-in egg whites and yolks. Each insecticide was applied to egg whites and yolks at a concentration of 1000 µg/g. After cooking the egg whites and yolks, concentrations of bifenthrin, DDD, and DDE decreased (P < 0.05), whereas those of fipronil and DDT were unchanged (P > 0.05) in both egg whites and yolks. Next, an in vitro human digestion model that simulates all the steps of human digestion was employed. Until digestion in the small intestine, the concentrations of fipronil and DDT in the cooked egg whites and yolks were unchanged (P > 0.05), whereas those of bifenthrin, DDD, and DDE decreased (P < 0.05) at each digestion step. In the large intestinal digestion step with Escherichia coli and Lactobacillus sakei as enterobacteria, the concentrations of all the insecticides decreased (P < 0.05) in the cooked egg whites and yolks. Among the insecticides, bifenthrin showed the lowest concentration (P < 0.05). In conclusion, the use of bifenthrin as an insecticide would be comparatively less toxic than other insecticides in terms of environmental pollution and human health, because of its easy degradation.

Effects of in vitro Human Digestion on the Antioxidant Activity and Stability of Lycopene and Phenolic Compounds in Pork Patties Containing Dried Tomato Prepared at Different Temperatures.

The antioxidant activity can be changed during digestion. The effects of in vitro human digestion on the antioxidant activity and stability of tomato powders (TPs), dried at three different temperatures (60, 80, and 100 °C) and added to pork patties (1% TP by weight), were investigated. The pork patties with three TPs underwent in vitro human digestion with enterobacteria. Lycopene and individual phenolic compounds were analyzed by using HPLC. The highest total phenolic compounds (6.96 g/100 g) and lycopene concentrations (2.68 mg/100 g) were observed in pork patties with TP dried at 100 °C. In addition, antioxidant activity of pork patties containing TPs were measured during in vitro human digestion. Gallic acid (23.8 to 41.6 g/100 g), chlorogenic acid (11.2 to 25.7 g/100 g), and caffeic acid (11.1 to 21.7 g/100 g) were detected as the main phenolic compounds in the TPs. Lycopene, and total and individual phenolic compound contents increased with increasing drying temperatures. Moreover, in vitro human digestion increased the antioxidant activity of TP-containing pork patties. The lycopene and total phenolics contents were increased during in vitro human digestion with enterobacteria by 146% to 220% and 1549% to 2095%, respectively as compared to the samples of before digestion. Hence, we hypothesized that the antioxidant activity of each TP increased during in vitro human digestion and depended on the amount of lycopene and phenolic compounds released. The TP dried at the highest temperature (100 °C) had the highest antioxidant activity in pork patties during in vitro human digestion. PRACTICAL APPLICATION: In this study, we revealed that in vitro human digestion increases the antioxidant activities of tomato powder. In addition, tomato powder dried at the highest temperature (100 °C) showed the highest antioxidant activity. Therefore, tomato powder at 100 °C could be used as strong antioxidants in meat products.

Effect of In Vitro Human Digestion on Biogenic Amine (Tyramine) Formation in Various Fermented Sausages.

Biogenic amines are formed in various fermented foods by microbial amino acid decarboxylation activities, and ingestion of these amines may cause human illness. However, the effect of digestion on the biogenic amines in fermented sausages has not been studied. This study was conducted to determine the effect of in vitro human digestion with the enterobacteria Escherichia coli and Lactobacillus casei on concentrations of the biogenic amine tyramine in six types of fermented sausages. Tyramine concentration was not significantly changed until simulated digestion in the small intestine. However, tyramine concentration for all sausage samples was increased after simulated digestion in the large intestine. Addition of E. coli and L. casei dramatically increased the tyramine concentrations ( P < 0.05). This result indicates that enterobacteria increase biogenic amine concentrations during human digestion.

Effect of six different starter cultures on the concentration of residual nitrite in fermented sausages during in vitro human digestion.

The objective of this study was to determine the effect of six different starter cultures of enterobacteria on the concentration of residual nitrite in fermented sausages during in vitro human digestion. Before digestion, the concentration of residual nitrite was dependent on starter culture in fermented sausage and ranged from 25.2 to 33.2mg/kg. Among the six starter cultures of enterobacteria, Pediococcus acidilactici, Pediococcus pentosaceus, and Staphylococcus carnosus showed higher nitrite depletion ability than the other three strains in fermented sausages. The concentration of residual nitrite in fermented sausages was significantly (p<0.05) decreased after stomach digestion and ranged from 17.4 to 21.6mg/kg. Enterobacteria Escherichia coli (E. coli) and/or Lactobacillus casei (L. casei) effectively increased the degree of depletion of residual nitrite in large intestine digestion. In conclusion, starter cultures could influence the concentration of residual nitrite during in vitro human digestion. They could deplete residual nitrite in fermented sausages.

Evaluation of Antioxidative Activity of Various Levels of Ethanol Extracted Tomato Powder and Application to Pork Patties.

This study was performed to evaluate antioxidant activity of tomato powder extracted by various concentrations of ethanol (0, 25, 50, 75, 100%) and to evaluate the physicochemical properties and antioxidant activities of pork patties with ethanol extracted tomato (EET) powder. No differences in the contents of total of individual phenolic compounds including gallic acid and catechin, were observed among the treatments (p>0.05). Among the various concentrations, 50% and 75% EET powder showed the highest free radical scavenging and iron chelating activities (p<0.05). Lipid peroxidation was retarded in linoleic acid emulsion with the addition of 50% and 75% EET powder (0.1%). Based on the model study, five pork patties were actually manufactured; control patty, reference patty with 0.01% of butylated hydroxytoluene, patty with 1% of water extracted tomato (WET), and patties with 0.5 and 1.0% of EET. Addition of 1% WET and EET decreased pH value, and increased redness values of pork patties, as compared to the control (p<0.05). Pork patties with WET (1.0%) and EET (0.5% and 1.0%) had lower 2-thiobarbituric acid reactive substances values compared with control patties after 7 d of storage (p<0.05). Pork patties containing EET powder showed lower total bacterial and Enterobacteriaceae counts than control patties (p<0.05). In conclusion, WET and EET (50%) could be used as a natural antioxidant and antimicrobial agent in meat products.

Changes of sodium nitrate, nitrite, and N-nitrosodiethylamine during in vitro human digestion.

This study aimed to determine the changes in sodium nitrate, sodium nitrite, and N-nitrosodiethylamine (NDEA) during in vitro human digestion, and the effect of enterobacteria on the changes in these compounds. The concentrations of nitrate, nitrite, and NDEA were significantly reduced from 150, 150, and 1ppm to 42.8, 63.2, and 0.85ppm, respectively, during in vitro human digestion (p<0.05). The enterobacteria Escherichia coli and Lactobacillus casei reduced the amount of these compounds present during in vitro human digestion. This study is the first to report that E. coli can dramatically reduce the amount of nitrite during in vitro human digestion and this may be due to the effect of nitrite reductase present in E. coli. We therefore conclude that the amounts of potentially harmful substances and their toxicity can be decreased during human digestion.

Effects of Drying Temperature on Antioxidant Activities of Tomato Powder and Storage Stability of Pork Patties.

This study was performed to evaluate the antioxidant activity of oven-dried tomato powder (OTP) as affected by drying temperature and the effect of OTP on the product quality of pork patties. Three OTP products were obtained by drying of fresh tomato at 60, 80 and 100℃ oven until constant weight was obtained. Total phenolic content of three kinds of OTPs ranged from 1.95 to 5.94 g/100 g. The highest amount of total phenolic compound was observed in OTP dried at 100℃. Antioxidant activity of three kinds of OTPs was measured by 1,1-diphenyl-2-pycrylhydrazyl (DPPH)-radical scavenging activity, iron chelating ability, reducing power and measurement of lipid peroxide in linoleic acid emulsion system. In all parameters, OTP at 100℃ showed the higher antioxidant activity than other temperatures (p<0.05). Based on the model study, the physicochemical properties, and antioxidant and antimicrobial activities of pork patties containing 1% OTP were measured. Redness of pork patties were increased with the addition of OTPs (p<0.05). Thiobarbituric acid reactive substances (TBARS) values of raw pork patties containing OTPs were lower than those of control (CTL) until 7 d of storage, regardless of drying temperatures (p<0.05). Peroxide values of pork patties made with OTP (1%) were lower than those of CTL until the end of storage time (p<0.05). However, no antimicrobial activities were observed among the treatments (p>0.05). Therefore, OTPs could be used as a natural antioxidant in meat products.

Evaluation of different drying temperatures on physico-chemical and antioxidant properties of water-soluble tomato powders and on their use in pork patties.

BACKGROUND: Tomato and tomato products provide various antioxidant activities, which could be changed by the processing method. This study was performed to evaluate the antioxidant activity of water-soluble tomato powder (WSTP) as affected by different oven temperatures (60, 80 and 100°C), and to evaluate the physico-chemical properties and antioxidative activities of pork patties containing these powders. RESULTS: The contents of total phenolic compounds of WSTP ranged from 22.2 to 69.6 g kg(-1) dry matter. The antioxidant activities increased significantly with increasing drying temperatures (P < 0.05). The physico-chemical properties of pork patties containing tomato powders were also evaluated. WSTP at 100°C showed the highest redness value compared to those dried at 60 and 80°C. Lipid oxidation of pork patties was retarded by 7 days with the addition of WSTP. In particular, pork patties containing WSTP showed antimicrobial activity at 14 days of refrigerated storage, regardless of drying temperatures. CONCLUSION: WSTP, especially prepared at 100°C, could be used as a natural antioxidant and antimicrobial agent in meat products.

Evaluation of Fermented Sausages Manufactured with Reduced-fat and Functional Starter Cultures on Physicochemical, Functional and Flavor Characteristics.

Fermented foods with probiotics having functional properties may provide beneficial effects on health. These effects are varied, depending on the type of lactic acid bacteria (LAB). Different probiotic LAB might have different functional properties. Thus, this study was performed to evaluate the quality of fermented sausages manufactured with functional starter cultures (Lactobacillus plantarum 115 and 167, and Pediococcus damnosus L12) and different fat levels, and to determine the optimum condition for the manufacture of these products. Medium-fat (~15%) fermented sausages reduced the drying time and cholesterol contents, as compared to regular-fat counterparts. In proximate analysis, the contents of moisture and protein of regular-fat products were lower than medium-fat with reduced fat content. The regular-fat products also had a lighter color and less redness, due to reduced fat content. Approximately 35 volatile compounds were identified in functional fermented sausages, and hexanal, trans-caryophyllene, and tetradecanal were the major volatile compounds. Selected mixed starter culture showed the potential possibility of replacing the commercial starter culture (LK30 plus) in flavor profiles. However, medium-fat fermented sausage containing selected mixed starter culture tended to be less acceptable than their high-fat counterparts, due to excess dry ring developed in the surface. These results indicate that the use of combinations of L. plantarum 115 and 167, and P. damnosus L12 as a starter culture, will prove useful for manufacturing the fermented sausage.