The Quality of Oranges and Clementines: Objective Parameters of Judgement

January 08, 2015

Guest columnist from Italy explores the relationship between price and quality in citrus fruits.

The Quality of Oranges and Clementines: Objective Parameters of Judgement 

Daniele Tirelli & Antonello Vilardi

Originally published by RETAIL WATCH (

Many people may doubt that objective measures such as gradation BRIX or PH are not sufficient to properly assess the quality of fruits and vegetables commonly offered by the channels of mass distribution. 

After all, it is no mystery that everything can be constrained. However, it should also be considered whether we should even have a reliable yardstick to assess simultaneously the quality of many perishable products, sold in various stores….the alternative of a sensory analysis, it is simply not feasible! 

Aside from the cost, how can you ask a taster to enjoy 70-80 oranges and classify them according to a comparable metric? A viable solution could be an indicator already used for the analysis of the grape: the ripeness

By the term "ripeness" is used to define the state resulting from the combination of sugars and acidity of a plant product. Here is the formula used in viticulture (where other methods also apply are much more sophisticated):

Ripeness = (Degrees °Brix) * (PH)2 

It is more than plausible to consider how the ordering of the judgment of liking the tasting of ordinary people, that is a large part of consumers, follow rather well (even in the case of citrus fruits) that of ripeness.

Returning to our topic, it becomes strange to note the resistance of many operators in the presence of the use of the degrees Brix, as an index to measure the quality of fruits and vegetables offered for sale when there are retailers, as in the case of STEW LEONARD'S at NORWALK (CT), in which this happened.

On the day in question, the fresh juice of oranges (prepared in the laboratory of the store) had a value around 11 degrees Brix, far from the ideal 15 degrees.

So Stew told his customers: "Hey, do not expect the best this season, with these varieties. This is what I can offer you honestly at this price”.  So clear agreements and… lasting loyalty. Customers appreciate the clarity and reason, if well guided!

But now we come to the characteristics of two citrus offered by supermarkets to consumers in Milan (Italy)…


(Purchased on 26-27 November 2014),they require a clarification.

In the case of citrus fruits, not everything is suitable to be eaten, as generally true for tomatoes. 

The juiciness varies greatly. 

The deviation of epicarp (orange peel), mesocarp (spongy white part) and membranes differs appreciably from fruit to fruit, unless there is a rigorous selection upstream.

In the case of Navel Oranges on the market, the rejection rate ranged between 43 and 67%, so while the gross price per kilogram ranged from € 0.89 to € 1.98, the price refers to the edible part had to be increased compared to the simple price per kg by removing the gap. The net price per kilogram ranged from € 2.02 to € 4.16.

First hypothesis. We estimate, then, what would get (on average) the consumer who had bought 1 kilogram of oranges at all supermarkets sample. And what would have spent. 

He would pay:

€ 3.33 per kg (juice!) of 38% of the product to below 10.5 °Brix, with a Ripeness 112;

€ 3.07 per kg (juice!) of 62% of the product above the 10.5 °Brix, with a Ripeness 120.

In essence, for Navel Oranges, prices do not match the qualityand the thing is not just to be underestimated!

Second hypothesis. If the consumer had instead bought the same amount only in CARREFOURwould spend € 0.98 per kg which by a margin of 51% (non-edible parts) would become € 2.02 (the lowest price among all!) for a juice from 12 °Brix average (the highest among all and in a range from 10.4 ° to 13.4 °), with a pH of 3.25 (average value). Ripeness: 128.

With these data, it is inevitable to congratulate Carrefour. 


(Purchased on November 11, 2014). The rejection rate was between 39% and 72%, so the gross price per kilogram ranged from € 1.50 to € 2.88; the price per kilogram of edible portion ranged from € 3.14 to € 5.91; the sweetness ranged from 8.8 °Bx to 16.9 °Bx.

First hypothesis. If the "ideal consumer" had bought 1 kg of Clementines in all supermarkets sample would have spent, on average, for this mix:

€ 4.08 per kg (juice!) to 40% of the product to below 11.0 °Bx, with a Ripeness of 115 and 10.1 °Bx average;

€ 4.26 per kg (juice!) for 60% of the product above the 11.0 °Bx, with a Ripeness of 138 and 12.1 °Bx average.

Second hypothesis. If the consumer had instead bought the same amount in IPERwould spend € 2.19 per kg gross, that by a margin of 55% (non-edible parts) would become of € 4.88 for juice from 12.2 °Bx average, with a pH of 3.39 (average value) Ripeness: 140

The flavors of the South-California “Gold Nugget” enjoy from BRISTOL FARMS in LA and systematically over 16 °Bx, are excellent, but this does not prevent our congratulations to IPER, for its clementines!