Consumer

San Marzano PDO tomato, an emblem of Italian cuisine

December 30, 2023

352

The San Marzano PDO (Protected Designation of Origin) tomato is one of the emblems of agricultural tradition and Italian cuisine. (1) This variety – originally from the Agro-Nocerino and Sarnese in the Campania region – has been the protagonist of the Mediterranean diet for centuries, as an ingredient based on the tomato preserves used to season Neapolitan pasta and pizza (2,3). An in-depth look.

Table of Contents

1) San Marzano PDO tomato, the story

The oral legend reports that the tomato, originally from Central America, reached Italy around 1770 thanks to a gift of seeds from the Kingdom of Peru to the Kingdom of Naples. These seeds would have been planted in the area that today corresponds to the municipality of San Marzano sul Sarno, in the province of Salerno, where over the centuries the relative cultivate.

Historical documents attest to the spread of San Marzano in the early 900s, thanks to the success of the first canning industries that transformed and packaged ‘peeled tomatoes’. The San Marzano tomato was once celebrated as ‘red gold’, thanks to the economic value it brought to the economy and employment in the Sarnese-Nocerino countryside.

2) Cultivation and characteristics of the fruit

The ‘San Marzano Tomato Agro Sarnese-Nocerino’ PDO is grown in 41 municipalities in the provinces of Salerno, Naples and Avellino. An area characterized by soils rich in minerals of volcanic origin and a temperate Mediterranean climate, two ideal conditions for growing this plant.

Solanum lycopersicum L. plants are grown vertically, with the help of guardians and a lot of manpower, respecting the centuries-old tradition. And the harvest is carried out strictly by hand, between the end of July and the end of September.

The fruit stands out for its elongated shape and fleshy pulp, with few seeds. The ripe fruit reaches an intense red tone. The thickness of the skin, greater than other varieties, keeps the San Marzano tomato intact during transport and processing. (4) And it makes peeling easier after a steam bath.

3) Peeled San Marzano PDO tomatoes

The name of protected origin (DOP or PDO, Protected Designation of Origin) exclusively designates two types of preserves: ‘whole peeled’ and ‘fillet peeled’ San Marzano PDO tomatoes.

The specification requires that the products respect the following characteristics:

– uniform red color (a/b colorimetric ratio > 2,2);

– elongated and parallelepiped shape;

– length 6-8 cm;

– absence of foreign flavors and odors;

– weight of the drained product > 65% of the net weight;

– refractometric residual > 4%;

– pH < 4,5.

Ingredients permitted: salt (< 3%), basil leaves, citric acid (< 0,5%), tomato juice, partially concentrated tomato juice, semi-concentrated tomato obtained exclusively from tomato fruits of the S. Marzano 2 and Kiros 2 varieties or improved lines, products in the Agro Sarnese-Nocerino.

4) Lycopene and health benefits

Tomatoes are rich in lycopene, a carotenoid that the human body is unable to synthesize and must therefore receive through consumption of foods that contain it.

Scientific literature has associated this antioxidant with important benefits for human health, linked to its ability to protect cells and DNA from oxidative stress and inflammation, key factors in the prevention of chronic diseases (5,6).

Tomato preserves contain lycopene in much higher concentrations than fresh fruits, thanks to its resistance to heat treatments which preserve its characteristics and properties.

5) The Consortium for the protection of San Marzano PDO

The protection consortium of the ‘San Marzano Tomato dell’Agro Sarnese-Nocerino’ PDO has been involved since 1996 in the promotion of the production chain, the conservation of the germplasm of native tomato ecotypes, the improvement of cultivation and agro-industrial transformation techniques, the protection of the profitability of farmers. (7)

Guardianship of consumers and international buyers regarding tomato food fraud – unfortunately still widespread, as we have seen (8,9) – is one of the missions of the Protection Consortium. The prevention and control of this type of ‘food fraud’ could be strengthened by:

– application of a public blockchain technology (i.e. Wiise Chain) to the traceability systems in use, (10)

– adoption of an innovative analysis system that allows us to trace the actual origin of the tomatoes used in preserves. This system was developed and scientifically validated in Italy but, curiously, it has not yet been used in official controls or in those of private analysis laboratories (11,12).

Dario Dongo