Nitrates and nitrites in vegetables and vegetable-based products and their intakes by the Estonian population

The content of nitrates were determined in 1349 samples of vegetables and ready-made food in 2003-2004 as a part of the Estonian food safety monitoring programme and the Estonian Science Foundation grant research activities. The results of manufacturers' analyses carried out for internal monitoring were included in the study. The highest mean values of nitrates were detected in dill, spinach, lettuce and beetroot. The mean concentrations were 2936, 2508, 2167 and 1446 mg kg^-1, respectively. The content of nitrites in samples was lower than 5 mg kg^-1. In total, the mean intake of nitrates by the Estonian population was 58 mg day^-1. The mean content of nitrates in vegetable-based infant foods of Estonian origin was 88 mg kg^-1. The average daily intake of nitrates by children in the age group of 4-6 years was 30 mg. The infants' average daily intake of nitrates from consumption of vegetable-based foods was 7.8 mg.     

Polycyclic aromatic hydrocarbons (PAHs) in meat products and estimated PAH intake by children and the general population in Estonia

The concentrations of benzo[a]pyrene and 11 other polycyclic aromatic hydrocarbons (PAHs) were analysed from 322 commercial, cured meat products and 14 home-grilled meat samples as part of the Estonian food safety monitoring programme during 2001-2005. The maximum acceptable concentration of 5 µg kg^-1 for benzo[a]pyrene was exceeded in 3.4% of samples. The highest PAH concentrations were detected in home-grilled pork samples. Using of disposable grilling unit resulted in 1.6 times higher PAH concentrations compared to the traditional wood-burning grill. The average intake of benzo[a]pyrene and sum of 12 PAHs from meat products was estimated for children (age 1-16 years) on the basis of an individual food consumption questionnaire and, for the general population, based on national food consumption data. The highest total PAH concentrations detected were 16 µg kg^-1 in smoked meat and ham, 19 µg kg^-1 in smoked sausage and 6.5 µg kg^-1 in smoked chicken samples. Since smoking and grilling are prevalent meat-cooking methods in Estonia, the impact of meat products is assessed to be significant in overall PAH intake.     

Estimated dietary intake of nitrite and nitrate in Swedish children

This study examines the intake of nitrate and nitrite in Swedish children. Daily intake estimates were based on a nationwide food consumption survey (4-day food diary) and nitrite/nitrate content in various foodstuffs. The mean intake of nitrite from cured meat among 2259 children studied was 0.013, 0.010 and 0.007 mg kg(-1) body weight day(-1) in age groups 4, 8-9 and 11-12 years, respectively. Among these age groups, three individuals (0.1% of the studied children) exceeded the acceptable daily intake (ADI) of 0.07 mg nitrite kg(-1) body weight day(-1). The mean intake of nitrate from vegetables, fruit, cured meat and water was 0.84, 0.68 and 0.45 mg kg(-1) body weight day(-1) for children aged 4, 8-9 and 11-12 years, respectively. No individual exceeded the ADI of 3.7 mg nitrate kg(-1) body weight day(-1). However, when the total nitrite intake was estimated, including an estimated 5% endogenous conversion of nitrate to nitrite, approximately 12% of the 4-year-old children exceeded the nitrite ADI. Thus, the intake of nitrite in Swedish children may be a concern for young age groups when endogenous nitrite conversion is included in the intake estimates.     

Time-dependent depletion of nitrite in pork/beef and chicken meat products and its effect on nitrite intake estimation

The food additive nitrite (E249, E250) is commonly used in meat curing as a food preservation method. Because of potential negative health effects of nitrite, its use is strictly regulated. In an earlier study we have shown that the calculated intake of nitrite in children can exceed the acceptable daily intake (ADI) when conversion from dietary nitrate to nitrite is included. This study examined time-dependent changes in nitrite levels in four Swedish meat products frequently eaten by children: pork/beef sausage, liver paté and two types of chicken sausage, and how the production process, storage and also boiling (e.g., simmering in salted water) and frying affect the initial added nitrite level. The results showed a steep decrease in nitrite level between the point of addition to the product and the first sampling of the product 24 h later. After this time, residual nitrite levels continued to decrease, but much more slowly, until the recommended use-by date. Interestingly, this continuing decrease in nitrite was much smaller in the chicken products than in the pork/beef products. In a pilot study on pork/beef sausage, we found no effects of boiling on residual nitrite levels, but frying decreased nitrite levels by 50%. In scenarios of time-dependent depletion of nitrite using the data obtained for sausages to represent all cured meat products and including conversion from dietary nitrate, calculated nitrite intake in 4-year-old children generally exceeded the ADI. Moreover, the actual intake of nitrite from cured meat is dependent on the type of meat source, with a higher residual nitrite levels in chicken products compared with pork/beef products. This may result in increased nitrite exposure among consumers shifting their consumption pattern of processed meats from red to white meat products.     

Exposure estimates of nitrite and nitrate from consumption of cured meat products by the U.S. population

The dietary exposures of nitrite and nitrate from consumption of cured meat products were estimated for the U.S. population aged 2 years and older, and children aged 2 to 5 years, using both 2-day food consumption data from the publicly available combined 2009–2012 National Health and Nutrition Examination Survey (NHANES) and 10–14-day food consumption data from the 2009 and 2012 NPD Group, Inc. National Eating Trends-Nutrient Intake database (NPD NET-NID), and residual nitrite and nitrate levels in cured meat products available from the recent American Meat Institute Foundation/National Pork Board (AMIF/NPB) national market survey of the nitrite and nitrate levels in cured meat products in the U.S.A. The dietary exposure for consumers of cured meat products (eaters-only) was estimated at the mean and 90th percentile for three exposure scenarios: low exposure, average exposure, and high exposure, to account for the range in the amount of nitrite and nitrate in a given cured meat product category. In addition, a cumulative exposure that takes into account all cured meat product categories containing nitrite and nitrate was determined, and the relative percent contribution of each cured meat product category to the cumulative exposure was estimated. Cured, cooked sausages and whole-muscle brine-cured products were the two major contributing categories to dietary exposure of nitrite and nitrate for both U.S. population aged 2 years and older and children aged 2–5 years.     

Estimated dietary intake of nitrite and nitrate in Swedish children

This study examines the intake of nitrate and nitrite in Swedish children. Daily intake estimates were based on a nationwide food consumption survey (4-day food diary) and nitrite/nitrate content in various foodstuffs. The mean intake of nitrite from cured meat among 2259 children studied was 0.013, 0.010 and 0.007?mg?kg^?1?body?weight?day^?1 in age groups 4, 8–9 and 11–12 years, respectively. Among these age groups, three individuals (0.1% of the studied children) exceeded the acceptable daily intake (ADI) of 0.07?mg?nitrite?kg^?1 body weight?day^?1. The mean intake of nitrate from vegetables, fruit, cured meat and water was 0.84, 0.68 and 0.45?mg?kg^?1 body weight?day^?1 for children aged 4, 8–9 and 11–12 years, respectively. No individual exceeded the ADI of 3.7?mg?nitrate?kg^?1 body weight?day^?1. However, when the total nitrite intake was estimated, including an estimated 5% endogenous conversion of nitrate to nitrite, approximately 12% of the 4-year-old children exceeded the nitrite ADI. Thus, the intake of nitrite in Swedish children may be a concern for young age groups when endogenous nitrite conversion is included in the intake estimates.     

Nitrite and nitrate content in meat products and estimated intake in Denmark from 1998 to 2006

The content of nitrite and nitrate in cured meat products has been monitored in Denmark seven times between 1995 and 2006. The maximum permitted added amounts of sodium nitrite in Denmark (60 mg kg(-1) for most products up to 150 mg kg(-1) for special products) have not been exceeded, except for a few samples back in 2002. The intake, mean and intake distribution of sodium nitrite have been calculated from 1998 to 2006 with data from the Danish dietary survey conducted in 2000-02 on Danes from four to 75 years of age. The amounts used by industry have been relatively stable through the whole period with levels varying between 6 and 20 mg sodium nitrite kg(-1) with sausages, meat for open sandwiches and salami-type sausages being the greatest contributors. The mean intake of sodium nitrate was around 1 mg day(-1), which is very low compared with the total intake of 61 mg day(-1). The mean intake of sodium nitrite was 0.017 and 0.014, 0.009 and 0.008, and 0.007 and 0.003 mg kg(-1) body weight day(-1) for men and women in the age groups 4-5, 6-14 and 15-75 years, respectively, which was much lower than the acceptable daily intake (ADI) of 0.09 mg kg(-1) body weight day(-1). The 99th percentile for the group of 4-year-olds was 0.107 and 0.123 mg kg(-1) body weight day(-1) for boys and girls, respectively, and the 95th percentile was 0.057 and 0.073 mg kg(-1) body weight day(-1) for boys and girls, respectively, highest for the girls. With fewer than 100 boys and girls in the 4-5-year age group, only very few persons were responsible for the high intake. The conversion of nitrate to nitrite in the saliva and the degradation of nitrite during production and storage must also be considered when evaluating the intake of nitrite.     

Intake and risk assessment of nitrate and nitrite from New Zealand foods and drinking water

Exposure to excess nitrite is a potential health risk for humans. One hundred meat and processed foods and 100 vegetable samples purchased from New Zealand retail outlets were prepared as for consumption and analysed for nitrite and nitrate concentration using a standard, validated methodology. Nitrate concentrations ranged from less than the limit of detection (LOD = 5 mg kg^-1) in cheddar cheese and cream cheese-based dips to 3420 mg kg^-1 in lettuce. Nitrite was detected in half the processed foods and meats analysed (levels up to 119 mg kg^-1), but detected in only one vegetable sample above the LOD (broccoli at 27 mg kg^-1 nitrite). Concentration data were combined with 24 h dietary recall information to generate 4398 individual adult daily exposure scenarios for exogenous nitrite and nitrate including a contribution from water assessed from 1021 drinking water samples. The mean adult daily intake of exogenous nitrate and nitrite from food and water combined was 16 and 13% of the Acceptable Daily Intake (ADI), respectively, and therefore should not pose a health risk for the average consumer. A maximally exposed New Zealand adult is estimated to have an intake of up to seven times the ADI for nitrate. When the endogenous conversion of nitrate to nitrite is taken into account, approximately 10% of people with an average rate of conversion and half of all people with a high rate of conversion are estimated to exceed the ADI. Either the ADI is inappropriate and needs to be re-evaluated, or those individuals who have a high rate of conversion of nitrate to nitrite are at risk to adverse effects of nitrite exposure.     

Effect of ascorbic acid on the hepatotoxicity due to the daily intake of nitrate, nitrite and dimethylamine

It is known that nitrates, nitrites and dimethylamine may react in the gastro-intestinal tract synthesizing the powerful hepatotoxic and carcinogenic dimethylnitrosamine. The purpose of this study was to investigate hepatotoxicity due to the daily intake of nitrates and nitrites administered to rats during 14 weeks together with dimethylamine in drinking water, and to evaluate the protecting effect of ascorbic acid against the hepatotoxicity of the presumably endogenous formed dimethylnitrosamine. The toxicity criteria studied were weight of liver (absolute and relative), free and total bilirubin, alkaline phosphatase and pyruvic glutamic transaminase, all in the form of serum, and histopathologic tests of the liver. The results gave evidence of hepatotoxicity induced by the intake of nitrate, nitrite and dimethylamine all together, and not through the only intake of nitrate or nitrite or of amine. Daily doses of ascorbic acid [(211 +/- 40) and (18 +/- 4) mg/kg] seemed to hinder hepatotoxicity according to the criteria under investigation.     

Development of methodical approaches to determination of nitrates and nitrites in multicomponent salting mixtures used in meat product industry]

A unified photometric method for determination of nitrates and nitrites in multicomponent salting mixtures containing sodium nitrate and nitrite, chlorides, phosphates, polyphosphates, ascorbic acid, or ascorbates, antioxidants, organic acids, vegetative and animal proteins, carbohydrates is proposed. With use of the developed method, content of nitrates and nitrites in a number of salting mixtures meat production was estimated.     

Citrus Co-Products as Technological Strategy to Reduce Residual Nitrite Content in Meat Products

ABSTRACT:  Sodium or potassium nitrite is widely used as a curing agent in cured meat products because it inhibits outgrowth and neurotoxin formation by  Clostridium botulinum , delays the development of oxidative rancidity, develops the characteristic flavor of cured meats, and reacts with myoglobin and stabilizes the red meat color. As soon as nitrite is added in the meat formulation, it starts to disappear and the nitrite that has not reacted with myoglobin and it is available corresponds to residual nitrite level. Health concerns relating to the use of nitrates and nitrites in cured meats (cooked and dry cured) trend toward decreased usage to alleviate the potential risk to the consumers from formation of carcinogenic compounds. Recently, some new ingredients principally agro-industrial co-products in general and those from the citrus industry in particular (albedo [with different treatments], dietetic fiber obtained from the whole co-product, and washing water used in the process to obtain the dietetic fiber) are seen as good sources of bio-compounds that may help to reduce the residual nitrite level in meat products. From these co-products, citrus fiber shows the highest potential to reduce the residual nitrite level, followed by the albedo and finally the washing water. The aim of this article is to describe the latest advances concerning the use of citrus co-products in meat products as a potential ingredient to reduce the nitrite level.     

Spectrophotometric Determination of Nitrite and Nitrate in Cured Meat by Sequential Injection Analysis

ABSTRACT: A robust, automated, labor-saving, accurate, and economical sequential injection system was developed for simultaneous determination of nitrite and nitrate in cured meat samples, based on the Shinn reaction. Nitrite is coupled and diazotized with sulfanilamide and N-(1-naphtyl)-ethylenediamine dihydrochloride, to form a colored compound that absorbs at 538 nm. Nitrate is previously in-line reduced to nitrite in a copperized cadmium column and measured as nitrite. The solutions' aspiration sequence, the influence of reagent and buffer concentrations, the manifold parameters, and the characteristics of the reducing column were studied. Nitrite and nitrate can be determined within the 0.030 to 1.22 of N-NO₂− and 0.034 to 3.95 mg/L of N-NO₃− ranges, respectively, at a sampling rate of 9/h. Detection limits of 9 μg/L of N for nitrite and 9 μg/L of N for nitrate were obtained, and the conversion rate of nitrate to nitrite was 100.6%± 1.8%. The results were in good agreement with those obtained by the reference methods, with relative standard deviations (r.s.d.) better than 3.70% for nitrites and 2.42% for nitrates.     

The occurrence of volatile N-nitrosamines in Estonian meat products

N-Nitrosamines (NAs) are a group of carcinogens, which have been detected in various meat products. The level of five NAs, namely N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosodibutylamine, N-nitrosopiperidine, and N-nitrosopyrrolidine was determined in 386 various samples of meat during 2001–2005. Raw, fried, grilled, smoked, pickled, and canned meat products were analyzed. For a sample cleaning the two-step solid-phase extraction with Extrelut and Florisil sorbents was used. NAs were separated by gas chromatography and detected by positive-ion chemical ionization using ammonia as reagent gas. The HP 6890 Plus GC/HP 5973 MSD was used in the selected ion-monitoring mode with pulsed splitless injection. In this work, the limit of detection and the limit of quantitation of NA were approximately 0.09 and 0.29 μg/kg, respectively, with about 85% recovery. NDMA was noted in above 88% of samples, NDEA in 27%, NPYR in 90%, NPIP in 65%, and NDBA in 33% at the mean levels of 0.85, 0.36, 4.14, 0.98, and 0.37 μg/kg, respectively. The level of total volatile NAs with the mean of 3.97 μg/kg was calculated.     

Determination of nitrites in meat systems: An improved procedure

Various analytical methods for nitrite determination in meat products, based on extraction of the preservative through digestion at 60–80 °C followed by colorimetric analysis gave relatively poor recoveries (44–65%) when applied to raw beef. An improved procedure was developed based on disintegration and dispersion of beef with sand prior to the extraction step and on the use of a higher concentration of N-(1-naphthyl) ethylenediamine dihydrochloride than normally used. The proposed technique resulted in almost 93% recovery of nitrites and showed a high precision revealed in a variation coefficient of %.     

Nitrate and nitrite quantification from cured meat and vegetables and their estimated dietary intake in Australians

High dietary nitrate and nitrite intake may increase the risk of gastro-intestinal cancers due to the in vivo formation of carcinogenic chemicals known as N-nitroso compounds. Water and leafy vegetables are natural sources of dietary nitrate, whereas cured meats are the major sources of dietary nitrite. This paper describes a simple and fast analytical method for determining nitrate and nitrite contents in vegetables and meat, using reversed-phase HPLC-UV. The linearity R² value was >0.998 for the anions. The limits of quantification for nitrite and nitrate were 5.0 and 2.5 mg/kg, respectively. This method is applicable for both leafy vegetable and meat samples. A range of vegetables was tested, which contained <23 mg/kg nitrite, but as much as 5000 mg/kg of nitrate. In cured and fresh meat samples, nitrate content ranged from 3.7 to 139.5 mg/kg, and nitrite content ranged from 3.7 to 86.7 mg/kg. These were below the regulatory limits set by food standards Australia and New Zealand (FSANZ). Based on the average consumption of these vegetables and cured meat in Australia, the estimated dietary intake for nitrate and nitrite for Australians were 267 and 5.3 mg/adult/day, respectively.     

替代亚硝酸盐生产安全腌肉制品的研究现状

硝酸盐和亚硝酸盐在腌肉制品加工中同时起着发色、抑菌、抗氧化和提高风味的作用,但硝酸盐和亚硝酸盐与肉中的二级胺反应会形成致癌物质N-亚硝胺,所以寻求一种更加安全有效的硝酸盐和亚硝酸盐替代方式,在实际生产中具有重要意义。本文就无硝腌肉制品在亚硝酸盐发色作用、抑菌作用和抗氧化作用的替代物方面开展的研究工作进行综述,提出了天然腌制的概念,重点介绍目前国内外利用蔬菜替代亚硝酸盐的方法,包括将蔬菜粉(或汁)中的硝酸盐用硝酸盐还原菌转化为亚硝酸盐后加入腌肉制品中(先发酵法)和将蔬菜粉(或汁)加入肉馅中再发酵(后发酵法)两种生产方式,并对目前的研究现状、进展、存在问题及今后发展方向进行了论述,以期为生产安全腌肉制品提供借鉴。     

Nitrite and nitrate content in meat products and estimated intake in Denmark from 1998 to 2006

The content of nitrite and nitrate in cured meat products has been monitored in Denmark seven times between 1995 and 2006. The maximum permitted added amounts of sodium nitrite in Denmark (60 mg kg^?1 for most products up to 150 mg kg^?1 for special products) have not been exceeded, except for a few samples back in 2002. The intake, mean and intake distribution of sodium nitrite have been calculated from 1998 to 2006 with data from the Danish dietary survey conducted in 2000–02 on Danes from four to 75 years of age. The amounts used by industry have been relatively stable through the whole period with levels varying between 6 and 20 mg sodium nitrite kg^?1 with sausages, meat for open sandwiches and salami-type sausages being the greatest contributors. The mean intake of sodium nitrate was around 1 mg day^?1, which is very low compared with the total intake of 61 mg day^?1. The mean intake of sodium nitrite was 0.017 and 0.014, 0.009 and 0.008, and 0.007 and 0.003 mg kg^?1 body weight day^?1 for men and women in the age groups 4–5, 6–14 and 15–75 years, respectively, which was much lower than the acceptable daily intake (ADI) of 0.09 mg kg^?1 body weight day^?1. The 99th percentile for the group of 4-year-olds was 0.107 and 0.123 mg kg^?1 body weight day^?1 for boys and girls, respectively, and the 95th percentile was 0.057 and 0.073 mg kg^?1 body weight day^?1 for boys and girls, respectively, highest for the girls. With fewer than 100 boys and girls in the 4–5-year age group, only very few persons were responsible for the high intake. The conversion of nitrate to nitrite in the saliva and the degradation of nitrite during production and storage must also be considered when evaluating the intake of nitrite.     

Assessment of dietary exposure of nitrate and nitrite in France

The aim of this study was to assess the dietary exposure of nitrate and nitrite in France. A total of 13, 657 concentration levels of nitrate and nitrite measured in food, representing 138 and 109 food items, respectively, and coming from French monitoring programmes between 2000 and 2006, were used. Depending on the non-detected and non-quantified analysis treatment, lower and upper concentration mean estimates were calculated for each food item. These were combined with consumption data derived from 1474 adults and 1018 children from the French national individual consumption survey (INCA1), conducted in 1999 and based on a 7-day food record diary. A total of 18% of spinaches, 6% of salads, 10% of cheeses, 8% of meat products and 6% of industrial meat products exceeded the European nitrate maximum level or maximum residual level. A total of 0.4% of industrial meat products and 0.2% of meat products exceeded their European nitrite maximum level or maximum residual level. Nitrate dietary exposure averaged 40% of the acceptable daily intake (ADI; 3.7 mg kg(-1) body weight day(-1)) for adults and 51 - 54% of the ADI for children with the major contributors being, for adults and children, respectively, vegetables (24 and 27% of ADI), potatoes (5 and 11% of ADI), and water (5 and 5% of ADI). The individual nitrate dietary intake of 1.4% (confidence interval (CI(95th)) [0.8; 2.0]) to 1.5% (CI(95th) [0.9; 2.1]) of adults and 7.9% (CI(95th) [6.2; 9.6]) to 8.4% (CI(95th) [6.7; 10.1]) of children were higher than the ADI. Nitrite dietary exposure averaged 33-67% of the ADI (0.06 mg kg(-1) body weight day(-1)) for adults and 67-133% of the ADI for children, with contributions of additive food vectors at 33% of ADI for adults and 50-67% of ADI for children. The individual nitrite dietary intake of 0.7% (CI(95th) [0.3; 1.1]) to 16.4% (CI(95th) [14.5; 18.3]) of adults and 10.5% (CI(95th) [8.6; 12.4]) to 66.2% (CI(95th) [63.3; 69.1]) of children were higher than the ADI.     

Assessment of dietary exposure of nitrate and nitrite in France.

The aim of this study was to assess the dietary exposure of nitrate and nitrite in France. A total of 13, 657 concentration levels of nitrate and nitrite measured in food, representing 138 and 109 food items, respectively, and coming from French monitoring programmes between 2000 and 2006, were used. Depending on the non-detected and non-quantified analysis treatment, lower and upper concentration mean estimates were calculated for each food item. These were combined with consumption data derived from 1474 adults and 1018 children from the French national individual consumption survey (INCA1), conducted in 1999 and based on a 7-day food record diary. A total of 18% of spinaches, 6% of salads, 10% of cheeses, 8% of meat products and 6% of industrial meat products exceeded the European nitrate maximum level or maximum residual level. A total of 0.4% of industrial meat products and 0.2% of meat products exceeded their European nitrite maximum level or maximum residual level. Nitrate dietary exposure averaged 40% of the acceptable daily intake (ADI; 3.7 mg kg(-1) body weight day(-1)) for adults and 51 - 54% of the ADI for children with the major contributors being, for adults and children, respectively, vegetables (24 and 27% of ADI), potatoes (5 and 11% of ADI), and water (5 and 5% of ADI). The individual nitrate dietary intake of 1.4% (confidence interval (CI(95th)) [0.8; 2.0]) to 1.5% (CI(95th) [0.9; 2.1]) of adults and 7.9% (CI(95th) [6.2; 9.6]) to 8.4% (CI(95th) [6.7; 10.1]) of children were higher than the ADI. Nitrite dietary exposure averaged 33-67% of the ADI (0.06 mg kg(-1) body weight day(-1)) for adults and 67-133% of the ADI for children, with contributions of additive food vectors at 33% of ADI for adults and 50-67% of ADI for children. The individual nitrite dietary intake of 0.7% (CI(95th) [0.3; 1.1]) to 16.4% (CI(95th) [14.5; 18.3]) of adults and 10.5% (CI(95th) [8.6; 12.4]) to 66.2% (CI(95th) [63.3; 69.1]) of children were higher than the ADI.     

盐水火腿加工中影响亚硝基化合物生成因素的研究

在肉类加工中亚硝酸盐和硝酸盐是很常用的食品添加剂,可以改善肉的色泽和风味,延迟脂肪的氧化和酸败,并且抑制肉毒梭状芽孢杆菌的繁殖,从而延长肉制品的货架期。但20世纪70年代人们发现了这些添加剂的危害:它们可以和氨基酸等含氮化合物反应生成致癌物-亚硝胺。而且亚硝酸盐在胃液环境下也可以形成亚硝胺。本文主要研究盐水火腿加工过程中,腌制时间、煮制时间和煮制温度以及亚硝酸钠和抗坏血酸钠的添加量对最终产品中残留的亚硝酸钠和生成的亚硝胺含量的影响,以期加工出更安全卫生的肉制品。研究表明,腌制时间控制在24h,亚硝酸钠的添加量为0.12g/kg,抗坏血酸钠的添加量为0.64g/kg,而煮制温度为85℃,煮制时间为1h(肉块大小为250g)时产品既能保持良好的色泽,又能使亚硝基化合物的含量降到最低水平。