Adulteration Rates Research Articles

Screening Method for Argan Oil Adulteration with Vegetable Oils: An Online HPLC Assay with Postcolumn Detection Utilizing Chemometric Multidata Analysis

This study is focused on examining the tocopherol isomers (α-, γ-, and δ-) fingerprinting by online RP-HPLC analysis with post column detection using CUPRAC (cupric reducing antioxidant capacity) methodology for argan oil authenticity. The proposed online assay was validated with good precision, reproducibility, and linearity. Sixteen argan oil samples (100% pure-certified and other commercial argan oils), possible adulterating vegetable oils (i.e., olive, sunflower, corn, and soya oils), and virgin argan oil blended with olive, sunflower, corn, and soya oils at levels of 5%, 10%, 15%, and 20% were analyzed. Spectrophotometric CUPRAC, DPPH, and ABTS assays were applied. Discrimination of fraudulent argan oils from virgin samples was performed by utilizing orthogonal partial least-squares discriminant analysis (OPLS-DA) regression modeling with good sensitivity and specificity. We suggested [γ-toc/α-toc] value as a new first screening adulteration factor (AF) that could be used to assess fraudulent argan oil samples. The distinct decrement in AF value was observed by the increase of adulteration rate. The AF values for virgin argan oils were ranged from 11.8 (lower limit) to 18.6 (upper limit). The presence of β-sitosterol detected in commercial argan oils (with AF values out of limit values) was evaluated as fraudulent which was in accordance with the proposed assay. Our method enabled the detection of argan oil samples at adulteration levels of >5% in the case of sunflower, olive, and soya oils, >15% in the case of corn oil. This method may be an alternative and specific assay for the authentication and quality detection of commercial argan oils.

Identification of flower herbs in Chinese pharmacopoeia based on DNA barcoding

ObjectiveFlower herbs are an important category of traditional Chinese medicinal materials, some of which are used as healthcare tea in folk. However, the increasing adulteration of medicinal herbs is threatening consumer safety. The adulteration of flower herbs and their healthcare tea products in the market were investigated. MethodsA total of 33 flower herb samples from several retail pharmacies in China were randomly collected and 27 flower healthcare tea samples were purchased online. They were identified using ITS2-based Traditional Chinese Medicine Database (TCMD). Additionally, Lonicerae Japonicae Flos and the adulterants were compared in the ITS2 secondary structures. ResultsThere were one adulterant (Inulae Flos) in flower herb materials and eight adulterants in healthcare tea samples. Inula linariifolia was an adulterate species of Inulae Flos, Robinia pseudoacacia was of Sophorae Flos, and Lonicera macranthoides was of Lonicerae Japonicae Flos. Sophorae Flos and Lonicerae Japonicae Flos were two healthcare tea products with high adulteration rates. ConclusionThe TCMD is powerful tool to identify flower herbs and the adulterants that frequently occurred in the flower herb market, especially online shops.

Quality Assurance of Meat and Poultry products using Advanced Biotechnological Methods

Nowadays, meat adulteration constitutes an important problem in Egypt. Adulteration causes many problems that need to be considered as economic issues arising from replacement of high commercial value meat species with cheaper or undesired meats, religious issues as pork meat prohibited for Muslims and allergic reactions arising from consumption of some special meats as equine meat species and others. The current study includes a surveillance study aimed to detect the adulteration of beef and poultry meat products with equine and or pork meat species in Damanhur city, El Behera Governorate, Egypt. Over a limited period of one year from February, 2015 to February, 2016, A total of 156 samples of meat and chicken products were collected and divided into two groups; Group (A) includes 96 packaged high brands of three meat processing plants including beef luncheon, burger and kofta (18 samples each), chicken luncheon (18), chicken burger (12) and chicken kofta (12) and Group (B) includes 60 non-packaged low brand samples of beef luncheon, burger, kofta, minced meat and sausage(6 samples each) and chicken luncheon, burger, kofta, minced meat and sausage (6 samples each) from meat shops. All samples were analyzed for detection of adulteration with equine and/or pork meat by Polymerase Chain Reaction (PCR) technique using specific primers for equine and pork species. The obtained result revealed that adulteration rate of processed meat products with equine meat species was found to be 3.2 % (5 positive samples out of 156 examined samples) so it was recommended that rapid movement of responsible authorities with cooperation with scientific academies to protect health of consumers and prevent illegal substitution of meat.

Hygienic quality, adulteration of pork and histamine production by Raoultella ornithinolytica in milkfish dumpling

Ten milkfish dumpling products purchased from retail stores in southern Taiwan were collected to determine the occurrence of biogenic amines, histamine-forming bacteria, and adulteration of pork. This study showed the high contents of aerobic plate count (APC), total coliforms (TC) and Escherichia coli in tested milkfish dumpling samples, whereas the average content of various biogenic amines in all tested samples was < 1.6 mg/100 g (< 0.05 to 1.54 mg/100 g). Three histamine-producing bacterial strains (2 isolates of Raoultella ornithinolytica and 1 isolate of Enterobacter aerogenes) isolated from tested samples produced 276.6 ppm to 561.8 ppm of histamine in trypticase soy broth supplemented with 1.0% L-histidine (TSBH). Assay of multiplex polymerase chain reaction (PCR) revealed that the adulteration rates were 50% (5/10) for pork in milkfish dumplings. In addition, milkfish dumpling stuffing was inoculated with R. ornithinolytica at 5.0 log colony forming units (CFU)/g and stored at various temperatures from 4°C to 37°C to investigate bacterial growth and formation of histamine. The histamine contents quickly increased to higher than 50 mg/100 g in samples stored at 37°C and 25°C within 24 hours and 36 hours, respectively, as well as stored at 15°C within 48 hours. Therefore, bacterial growth and histamine formation were controlled by cold storage of the samples at 4°C.

Oxygenated heterocyclic compounds to differentiate Citrus spp. essential oils through metabolomic strategies

This study aimed to characterise and discriminate 44 authenticated commercial samples of citrus essential oils (EO) from seven species (bergamot, lemon, bigarade, orange, mandarin, grapefruit, lime) by analysing the non-volatile oxygenated heterocyclic compounds (OHC) by UHPLC/TOF-HRMS, multivariate data analysis (PCA, PLS-DA) and metabolomic strategies; the OHC fraction includes coumarins, furocoumarins, and polymethoxylated flavonoids. Two different approaches were adopted: (i) targeted profiling based on quantifying 18 furocoumarins and coumarins, some of which are regulated by law, and (ii) targeted fingerprinting based on 140 OHCs reported in citrus essential oils, from which 38 discriminant markers were defined. This approach correctly discriminated the Citrus species; its “sensitivity” to relatively low adulteration rate (10%) was highly satisfactory. The proposed method is complementary to that of analysing the citrus EO volatile part by GC techniques.

Determination of the adulteration of butter with margarine by using fat constants

This study focused on the adulteration of butter by margarine. The samples of pure butter, pure margarine and replacement of butter with margarine at a ratio of 10, 20, 30, 40, 50, 60, 70, 80 and 90% were prepared and fat constants including the Melting Point (MP), Refractive Index (RI), Reichert-Meissl Number (R-MN), Polenske Number (PN), Saponification Number (SN) and Iodine Number (IN) were measured for 66 samples (2 margarine types × 11 margarine replacements × 3 replicates). The types and addition levels of margarine significantly influenced the MP, R-MN, PN, SN, IN (P<0.01) and RI (P<0.05) of the samples. The fat constants in the samples became closer to margarine by increasing the levels of margarine. For each margarine added samples, the MP, R-MN, SN and IN were found to be statistically significant. According to these results, the MP, R-MN, SN and IN can be reliably used to differentiate margarine added butter from pure butter. The results were also supported by correlation analysis. As a result of this research, taking advantage of the R-MN, the following formula was developed to determine the addition of margarine to butter. Margarine adulteration rate (%)= 100.73 - (3.84 × Reichert-Meissl number), (F= 12830.43**)

Discrimination of Adulterated Sesame Oil Using Mid-infrared Spectroscopy and Chemometrics

There is usually some fake sesame oil in Chinese market that mixes sesame oil flavor into other kinds of edible oils to cheat customers, but it is hard to discriminate. A new analytical method based on directly mid-infrared spectroscopy combined with chemometrics was studied for identifying adulterated sesame oil in this study. We analyzed the spectral characteristics of sesame oil, three kinds of edible oils, and sesame oil flavor and found that there are obvious spectral differences between them. Through principal component analysis (PCA) method, the pure sesame oil and other edible oils that mixed with sesame oil flavor can be obviously classified. To further demonstrate the ability of infrared spectroscopy to discriminate fake sesame oil, we established independent modeling of class analogy (SIMCA) and partial least square discriminate analysis (PLS-DA) model and found there are effective for discrimination. We also studied the spectral changes with different adulteration rates of sesame oil flavor and found that the absorption peak at 1055–1025 cm−1 was weakened and shifted with the increase in the concentration of sesame oil flavor.

Biogenic amine content, histamine-forming bacteria, and adulteration of pork in tuna sausage products.

Twenty-five tuna sausage products were purchased from retail markets in Taiwan. The rates of occurrence of biogenic amines, histamine-forming bacteria, and adulteration by pork and poultry were determined. The average content of various biogenic amines in all tested samples was less than 2.0 mg/100 g (<0.05 to 1.85 mg/100 g). Thirteen histamine-producing bacterial strains isolated from tested samples produced 12.1 to 1,261 ppm of histamine in Trypticase soy broth supplemented with 1.0% L-histidine. Among them, Raoultella ornithinolytica (one strain), Enterobacter aerogenes (one strain), and Staphylococcus pasteuri (two strains) were identified as prolific histamine formers. PCR assay revealed that the adulteration rates were 80% (20 of 25) and 4% (1 of 25) for pork and poultry, respectively, in tuna sausage. The fish species in the tuna sausage samples were identified as Thunnus albacares for 22 samples (88%), Thunnus alalunga for 1 sample (4%), and Thunnus thynnus for 1 sample (4%), whereas the remaining sample was identified as Makaira nigricans (blue marlin).

Biogenic amines content, histamine-forming bacteria, and adulteration of pork and poultry in tuna dumpling products

Nine tuna dumpling products were purchased at nine retail markets in southern Taiwan. Occurrence of biogenic amines, histamine-forming bacteria, and adulteration of pork and poultry were determined. This study showed the high contents of aerobic plate count, total coliform and Escherichia coli in tested tuna dumpling products. Average content of various biogenic amines in all tested samples was less than 2.0 mg/100 g. Fifteen histamine-producing bacterial strains isolated from tested samples produced 8.7–466 ppm of histamine in trypticase soy broth supplemented with 1.0% l-histidine (TSBH). Assay of multiplex polymerase chain reaction (PCR) revealed adulteration rates were 88.9% (8/9) and 33.3% (3/9) for pork and poultry, respectively, in tuna dumpling. In addition, six samples of tuna dumpling meat were identified as Thunnus obesus, while other three samples were identified as Thunnus thynnus.

Biogenic amines content, histamine-forming bacteria and adulteration of bonito in tuna candy products

Thirty-four tuna candy products sold in retail markets and supermarkets in Taiwan were purchased and tested to determine the biogenic amine, histamine-forming bacteria, and adulteration of bonito meat. The levels of pH value, water activity (Aw), water content, total volatile basic nitrogen (TVBN), aerobic plate count (APC) and total coliform (TC) in all samples ranged from 5.3 to 6.1, 0.47 to 0.65, 7.37% to 17.32%, 12.1 to 54.6 mg/100 g, <1 to 6.2 log CFU/g and <3 to 1700 MPN/g, respectively. None of these sample contained Escherichia coli. The average content of various biogenic amines in all tested samples was less than 1.0 mg/100 g. Four histamine-producing bacterial strains isolated from tested samples produced 1.02–1.74 ppm of histamine in trypticase soy broth supplemented with 1.0% l-histidine (TSBH) after incubation at 35 °C for 24 h. Assay of multiplex polymerase chain reaction (PCR) revealed that adulteration rate of bonito meat was 26.5% (9/34) in tuna candy samples. Tuna species in tuna candy samples was identified as Thunnus albacares for 29 samples (85.3%), Thunnus alalunga for four samples (11.8%) and Thunnus obesus for one sample (2.9%) by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP).

The British Food Journal Volume 57 Issue 11 1955

In addition to the quarterly reports which public analysts are required to furnish to Food and Drugs Authorities, some analysts take a deal of trouble over annual reports, many of which often contain useful information. To those who are good enough to send us copies the British Food Journal tenders its thanks. It is realised, of course, that such reports are intended mainly for perusal by lay folk, as well as by those professionally concerned, in the various localities for which the analysts act. For that reason, and at the risk of being criticised for ungracious conduct, we feel impelled to offer the suggestion that care should invariably be taken to avoid the presentation of facts in such a manner as may be calculated to mislead the ordinary reader. There is ample scope, in our view, for further instructions or advice to be issued by the Ministry concerned with respect to foods and drugs respectively. For example, all statistical tables relating to samples of milk would be much more informative if the reports clearly distinguished between samples taken from bottles distributed to the public by retailers, samples from producer‐retailers and samples procured from farmers’ churns. There is little point in wrestling with elaborate and complicated tables of figures showing percentages of “ adulterated ” samples or the average composition of samples examined in various years and in various areas if the reader is left in ignorance of the circumstances in which the samples of milk have been procured. The public analyst of one large authority, which need not here be named, takes great trouble to discover the so‐called “ adulteration rate ” in the areas of several other authorities, and appears to have or to give the impression that a low rate of unsatisfactory samples of food and drugs in his area is a reassuring sign. Our own view is that it is nothing of the kind. What matters most, as we repeat with a regularity which is a bit monotonous, is the system adopted to select and obtain samples for analysis. If the sampling officers obtain, perhaps more or less at random, substantial numbers of samples of arrowroot, bacon, barley, blancmange powder, saccharin tablets, salt, semolina, sugar, treacle and tea, the so‐called adulteration rate is not likely to be so high as in an area where the sampling officers interest themselves more closely in spread bread‐and‐butter and hot milk at cafés, ice‐cream, “ butter sweets ” and sausages. To avoid misconception, we must add that we do not consider that the articles in this last group of foods are the most important that could with advantage be sampled— but it is a group the sampling of which in recent days has resulted in the discovery of numerous infringements.