The Investigation And Analysis Of Food Additives In Commercially Available Food In Licheng District Of Jinan From 2013 To 2015

Objective:This study investigated and analyzed the use of preservatives,sweeteners,whiteners,and color retention agents in commercially available foods in the Licheng District of Jinan City as well as the distribution and possible sources of hazards associated with these food additives,in order to understand the current situation regarding food safety and detect food safety hazards in time.The findings of this study can provide a scientific basis for assessing local food safety risk and making rational food choices.Methods:1.Sampling methodDuring 2013-2015,multistage stratified random sampling was employed to sample 7 categories of food available in the Licheng District's markets,including dried aquatic products,fruit preserves,frozen drinks,grape wine,cooked meat,food cured with sauces or salt,and dried edible fungi.10-30 products of each category were sampled every year.2.Testing methodsCurrent standard testing methods were optimized and then methodologically validated for use in this study.Benzoic acid,sorbic acid and saccharin sodium in the food samples were detected using optimized high performance liquid chromatography(HPLC).Sodium cyclamate and nitrites were detected by optimized capillary gas chromatography and optimized spectrophotometry,respectively.Sulfur dioxide was measured using the standard distillation method.3.Statistical analysisA database was set up in Excel and then analyzed using SPSS 19.0.The data from different groups were compared by Chi-squared test.Results:1.Results of methodological validation1.1 Benzoic acid,sorbic acid and saccharin sodiumThe correlation coefficients(r)ranged from 0.9997 to 0.9999.The detection limits ranged from 1.8 × 10-3g/kg to 3.2 × 10'3g/kg.The precision of the method was between 1.33%and 4.03%.1.2 Sodium cyclamateThe testing method delivered a correlation coefficient(r)of 0.9997,a detection limit of 0.11 g/kg,recovery rates of 92.2%-98.5%,and test precision of 2.47%-4.38%.1.3 NitritesThe correlation coefficient(r)was 0.9996,detection limit was 3.5×10-3 mg/mL,recovery rates were 94.1%-96.8%,and test precision was 3.30%-5.17%.2.Results of testing2.1 Results by yearThe additive content exceeded corresponding limits by 5.22%in 2013,7.06%in 2014,and 8.23%in 2015,on average.It is clear that the over-limit rate increased year by year from 2013 to 2015,but no statistically significant difference between years was observed(?2=1.74,P>0.05).2.2 Results by food categoryDifferent levels of food additives were detected in the seven categories of food.The additive detection rates among grape wine and food cured with sauces or salt were 100.00%.The other five categories can be ranked in descending order of additive detection rate as follow:dried aquatic products(92.00%),fruit preserves(77.50%),frozen drinks(72.00%),cooked meat(66.67%),and dried edible fungi(65.00%).The average additive level in food cured with sauces or salt was 30.91%higher than the corresponding limit,compared to the 12.50%in fruit preserves and 12.50%in dried edible fungi.The average additive levels in other food categories were below limits.The levels of sorbic acid,saccharin sodium,and especially benzoic acid in food cured with sauces or salt were above limits.Fruit preserves exhibited sodium cyclamate and sulfur dioxide levels above relevant limits.Sulfur dioxide was the only overused additive in dried edible fungi.2.3 Results by test itemThe test items can be ranked in descending order of additive detection rate as follows:sulfur dioxide(77.14%),nitrites(57.78%),benzoic acid(40.51%),sorbic acid(31.58%),saccharin sodium(18.22%),and sodium cyclamate(7.03%).The results show statistically significant differences.between test items in detection rate(?2=243.64,P<0.01).In descending order of over-limit rate,these items are benzoic acid(6.15%),sulfur dioxide(4.57%),sorbic acid(1.40%),sodium cyclamate(1.08%),saccharin sodium(0.44%),and nitrites(0.00%).The results demonstrate statistically significantdifferences between test items in over-limit rate(?2 =22.34,P<0.01).2.4 Results by category of food additiveThe four additive categories can be ranked in descending order of detection rate as follows:color retention agents(57.78%),whiteners(51.43%),preservatives(35.21%),and sweeteners(13.17%),showing statistically significant differences(?2=114.99,P<0.01).In descending order of over-limit rate,these additive categories are whiteners(4.00%),preservatives(3.12%),sweeteners(0.98%),and color retention agents(0.00%).There are no statistically significant difference between the additive categories in over-limit rate(x2=7.78,P>0.05).2.5 Results by type of food packageThe additive detection rates by food package are as follows:food with unified package:77.42%;unpacked food:87.65%.The over-limit rate among the unpacked food was 14.71%,significantly higher than the 1.29%in food with unified package(?2 =19.16,P<0.01).2.6 Results by food supplierFood suppliers involved in this study can be ranked in descending order of additive detection rate as follow:agricultural product market(100.00%).small supermarket(91.43%),specialty store(85.00%),and large supermarket(65.45%).In descending order of over-limit rate,these food suppliers are agricultural product market(27.69%),small supermarket(7.14%),specialty store(2.50%),and large supermarket(1.82%).Among these suppliers,agricultural product market showed the highest additive detection rate and over-limit rate,followed by small supermarket and specialty store.Large supermarket ranked the lowest in both rates.The differences between these suppliers were statistically significant in terms of both detection rate and over-limit rate(P<0.01).Conclusions:1.The optimized testing methods allow for easier and more efficient sample pretreatment and deliver highly linear standard curves,high precision and accuracy as desired.2.The over-limit rate of food additives in commercially available food in the Licheng District of Jinan City increased year by year from 2013 to 2015.Whiteners and preservatives are the major overused categories.3.Over-limit rate was seriously among samples of food cured with sauces or salt,fruit preserves,and dried edible fungi exhibited seriously high.Food cured with sauces or salt exhibited the highest over-limit rate,especially of benzoic acid.4.Unpacked food was less safe than food with unified package due to higher additive levels.5.Agricultural product market showed higher over-limit rate of additives than other types of food suppliers.