A trial investigating the symptoms related to pine nut syndrome.

During the last few years, thousands of cases of pine nut-related dysgeusia have been reported. The symptoms involved are predominantly related to taste disturbances such as a constant bitter or metallic taste. The taste disturbance has been reported to occur 1-2 days after ingestion of pine nuts from the species of Pinus armandii. This paper describes a small trial where six volunteers consumed six to eight pine nuts suspected to cause dysgeusia. Incubation periods, symptoms and their duration were recorded. The trial showed that all subjects had developed symptoms of pine nut-related dysgeusia. Four out of six subjects experienced the classical bitter and metallic taste 1-2 days after ingestion. Two subjects experienced minor symptoms such as dryness and a sensation of enlarged tonsils. After the disappearance of symptoms, laboratory tests determined the pine nuts to originate from the species of P. armandii. A follow-up conversation with the subjects after 1 year showed no recurrent symptoms.

PCR amplification of repetitive sequences as a possible approach in relative species quantification.

Both relative and absolute quantifications are possible in species quantification when single copy genomic DNA is used. However, amplification of single copy genomic DNA does not allow a limit of detection as low as one obtained from amplification of repetitive sequences. Amplification of repetitive sequences is therefore frequently used in absolute quantification but problems occur in relative quantification as the number of repetitive sequences is unknown. A promising approach was developed where data from amplification of repetitive sequences were used in relative quantification of species in binary mixtures. PCR LUX primers were designed that amplify repetitive and single copy sequences to establish the species dependent number (constants) (SDC) of amplified repetitive sequences per genome. The SDCs and data from amplification of repetitive sequences were tested for their applicability to relatively quantify the amount of chicken DNA in a binary mixture of chicken DNA and pig DNA. However, the designed PCR primers lack the specificity required for regulatory species control.

Authentication of meat and meat products.

In recent years, interest in meat authenticity has increased. Many consumers are concerned about the meat they eat and accurate labelling is important to inform consumer choice. Authentication methods can be categorised into the areas where fraud is most likely to occur: meat origin, meat substitution, meat processing treatment and non-meat ingredient addition. Within each area the possibilities for fraud can be subcategorised as follows: meat origin-sex, meat cuts, breed, feed intake, slaughter age, wild versus farmed meat, organic versus conventional meat, and geographic origin; meat substitution-meat species, fat, and protein; meat processing treatment-irradiation, fresh versus thawed meat and meat preparation; non-meat ingredient addition-additives and water. Analytical methods used in authentication are as diverse as the authentication problems, and include a diverse range of equipment and techniques. This review is intended to provide an overview of the possible analytical methods available for meat and meat products authentication. In areas where no authentication methods have been published, possible strategies are suggested.

Analytical methods for authentication of fresh vs. thawed meat - A review.

Proper labeling of meat products is important to ensure fair-trading and to enable consumers to make informed choices. Different investigations indicate that wrong labeling where thawed meat is labeled as fresh meat is present in 8-15% of analyzed samples. Enforcement of regulations requires adequate analytical methods where enzymatic-, DNA based-, spectroscopic-, bio imaging- and sensory techniques constitute the majority of published papers. The molecular changes that these techniques detect are described. The capability of both discrimination between fresh and thawed meat, and determination of frozen storage time are discussed for each of the analytical techniques. The products included in this review are primarily whole meat from Bos taurus (cow), Sus scrofus (pig) and Gallus gallus (chicken). The best analytical choice in the discrimination of fresh vs. thawed meat is concluded to be a combination of analytical methods.