Due to the high volume of global pistachio production and the fact that pistachio is mostly considered as a luxury product in the food industry (due to its high protein and fat content) and in order to protect consumer rights, compliance with the established standards of this product is of utmost importance. The pistachio standards set by Iran and the USA provide the following key quality indicators for in-shell pistachio: moisture, closed-shell pistachio, dark stained shells, cracks and laterally split shells, damage by pests, kernel, foreign matter, and uniformity in color, cultivar, and size.
Measuring and defining the permissible limit for each of these indicators is among the duties of standard-setting organizations.
These standards define the permissible limits of aflatoxins, ochratoxins, and percentage of contamination with a variety of microbes, heavy metals, and pesticide residues.
For example, the American Pistachio Standards for determining the ounce of pistachio and the permissible limit of quality determinants are defined below.
For example, the Iranian Pistachio Standards for determining the ounce of pistachio and the permissible limit of quality determinants are defined below.
Raw in-shell pistachio grading
Defects (based on weight percentage) | Momtaz Grade | Excellent Grade | First Grade | Second Grade | Third Grade |
Closed-shell and empty | 1 | 2 | 3 | 4 | 5 |
Maximum empty | 0.5 | 0.75 | 0.75 | 1 | 1 |
Adhering hull | 0.5 | 0.75 | 1 | 1.25 | 1.5 |
Dark-stained shells | 1 | 1.5 | 4 | 5 | 6 |
Non-split and not split on suture | 1 | 2 | 3 | 5 | 6 |
Semi-open | 5 | 10 | 18 | 25 | irregular |
External defects | 7 | 13 | 22 | 28 | irregular |
Shelled pistachio | 1 | 2 | 2.5 | 3 | 3.5 |
Damaged by pests | 3 | 4 | 5 | 5 | 6 |
Maximum visible pests | 1 | 2 | 3 | 3 | 3 |
Total kernel defects | 3 | 4 | 5 | 6 | 7 |
Foreign materials | 0.25 | 0.3 | 0.4 | 0.6 | 0.8 |
Foreign materials except hull | 0.2 | 0.2 | 0.25 | 0.25 | 0.3 |
Uniformity of cultivar | 1 | 2 | 3 | 4 | 5 |
Uniformity of size | 1.5 | 1.6 | 1.8 | 2 | 2.4 |
Iran’s national standards for pistachios are stricter than the American standards. These include the maximum moisture content of pistachio, for which the Iranian standards set the maximum 5% and the American standard the maximum 6.5%.
It should be noted that ounce is used to determine pistachio size. Therefore, the number of pistachios per 28.34 g of pistachio is estimated and considered as the ounce. The 18-20 ounce is known as the largest pistachio in Iran. This ounce belongs to Akbari pistachio and is sometimes applied to Kalleh Ghuchi pistachio. Iranian pistachios are divided into two types of round and long pistachios, and the ounce of long pistachios is more than that of the round ones. In the long pistachios, the ratio of the length to the largest width is greater than 1.52, but in the case of round pistachios, the ratio is less than or equal to 1.52.
According to the microbial standards of this product, the maximum permissible contamination to microbial agents, including coliform, E. coli, Salmonella, and mold is determined.
Heavy metals are also an important quality indicator in the food industry because of their accumulation in important body tissues and the risk of cancer. Heavy metals include mercury, arsenic, lead, and cadmium.
Pesticide residues also accumulate in various body tissues and cells, leading to a variety of diseases due to their long half-life. Iran’s national standard and international standards have defined the permissible limits of pesticide residues for pesticides used in pistachio orchards. Failure to comply with international standards regarding the above indicators would result in a decline in pistachio quality and even cargo rejections at the customs of destination ports.
Aflatoxin and ochratoxin, as important mycotoxins produced by plant saprophytic fungi, pose very high health risks and are important quality indicators for pistachios. Thus, strict rules and controls have been implemented to minimize the contamination of these toxins at the international level.
Behin Exir offers the best pistachios to the world market by making contracts with the largest national laboratory network approved by the Institute of Standards & Industrial Research of Iran.