Effect of Lentil s Variety and Cultural Farming System on Nutritional Value and Physicochemical Sensory Properties as Related to Human Daily Coverage

Rapid Communication

Int J Nutr Sci. 2021; 6(2): 1053.

Effect of Lentil’s Variety and Cultural Farming System on Nutritional Value and Physicochemical Sensory Properties as Related to Human Daily Coverage

Karagounis I¹, Avdikos ID², Pankou CI²*, Kostoula SD², Arambatzi P², Vlachostergios DN³ and Mavromatis AG²

1Department of Agriculture, School of Agricultural Sciences, Animal Production and Aquatic Environment, University of Thessaly, Greece

2Genetics and Plant Breeding, School of Agriculture, Aristotle University of Thessaloniki, Greece

3Institute of Industrial and Forage Crops, HAODEMETER, Larissa, Greece

*Corresponding author: Pankou CI, Genetics and Plant Breeding, School of Agriculture, Aristotle University of Thessaloniki, University Campus 54124, Thessaloniki, Greece

Received: May 01, 2021; Accepted: May 29, 2021; Published: June 05, 2021


The aim of this study is to determine if there is any influence of lentil variety and environment of cultivation in the chemical composition of seeds originating from organic and conventional farming systems. Particularly, an evaluation was made on the physicochemical properties of three lentil cultivars (‘Thessalia’, ‘Dimitra’, ‘Samos’) and also the effect of farming system towards the composition of seeds to be assessed for discovering the tendency which specific cultivar or farming system are most preferable for the consumers. For the evaluation of the physicochemical properties of lentil seeds: (a) Seed density, (b) Hydration coefficient, (c) Swelling coefficient, (d) pH and (e) Content in macro- and micronutrients (total nitrogen, phosphorus, potassium, calcium, magnesium, iron, zinc, manganese, and boron), were estimated. Multivariate statistical analysis was applied for every characteristic in order to determine similarities/ differences among the cultivars in both organic and conventional farming systems. In addition, Analysis of Variance (ANOVA) and Principal Component Analysis (PCA) were conducted. Regarding the three cultivars under evaluation, cv. ‘Dimitra’ is superior especially in the organic environment, followed by cv. ‘Thessalia’, whose nutritional value increases under organic farming conditions. While ‘Samos’ exhibited a slightly better performance under conventional conditions. Based on the results of this research, the interaction between the lentil cultivar and the cultivating environment can influence the nutritional value and the physicochemical properties of lentil’s seeds.

Keywords: Lens culinaris; Daily dietary value; Macronutrients; Micronutrients; PCA


Lentil (Lens culinaris Medik; Fabaceae) is an important food legume with various uses due to its protein-rich seeds [1]. It is a self-pollinated diploid plant species (2n=14) (Muehlbauer, 1991), adapted for culture in Mediterranean and subtropical dryland regions. Lentil seeds contain 19.5 - 35.5 % of protein, similar to that of peas (Pisum sativum L.) and beans (Phaseolus vulgaris L.), situ but less than soybean (Glycine max L. Merr.). Lentil is an excellent source of macro and micro-nutrients [2], having low levels of fat and natural fibers [3]. They comprise an exceptional source of macroand micronutrients like copper, iron, manganese, phosphorus, zinc, magnesium, potassium and selenium. Vandemark et al. [4], examined the relationship between seed mineral concentrations and several agronomical traits. They manage to determine concentrations of boron (B), calcium (Ca), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), nickel (Ni), phosphorus (P), selenium (Se), sulfur (S) and zinc (Zn) [4]. As well as its protein which is of high quality, fundamental amino acids and major minerals, lentil’s seed also contains iron up to 132ppm and zinc up to 98ppm. Plenty lentil varieties are being consumed when they contain iron >72ppm and zinc >64ppm in concentration. Also, lentil seed contains, vitamins like thiamine (vitamin B1), pyridoxine (vitamin B6), riboflavin (vitamin B2), niacin (vitamin B3), and 200mg/kg of β-carotene [3]. All the above clearly indicate that lentils could play an essential role in a healthy human diet.

Mineral deficiencies such as iron (Fe) and zinc (Zn) affect a lot of people worldwide. The supply of beneficial forms of these micronutrients in food and the impacts on human health are main topics of importance in public health [5]. In a study of Thavarajah et al. [6], the iron concentration varied from 7.3 to 9 mg/100g and zinc concentration ranged from 4.4-5.4 mg/100g, in Saskatchewan lentils. Additionally, 100g dry lentils can give 91-113 % of the RDA for males and 41-50 % for females as for iron, and 40-49 % of the RDA for males and 55-68 % for females, as for zinc concentration [6]. All these characteristics make lentils a valuable commodity. Lentil is also a great source of lysine and leucine, dietary fiber and complex carbohydrates. Additionally, its grains include vitamins, minerals, oleic, linoleic and palmitic acid [7].

Aside from seed chemical composition, genetic variability was reported for physicochemical properties, seed processing (like cooking), and seed size [8]. It was found that composition, minerals and anti-nutritional factors in lentils are affected by variety and processing [9]. Generally, the studies related to protein functional properties assess their gelling, emulsifying, foaming, solubility, water- and oil-absorption ability (physicochemical characteristics). However, most of the studies assess the functional properties only in a neutral pH [10]. Moreover, accepting the physicochemical properties provides better insights on their hydrothermal behaviour and helps in appropriate application of proteins [11]. The hydration capacity for lentil seeds was calculated by measuring the percentage of increase in mass of seeds when soaked in distilled water for 12 and 24 hours [8]. In another study [12], thirty-six lentil varieties were examined in organic and conventional farming systems for three years. These properties make lentils an important crop for human consumption and animal feed (grain mixtures and straw). Nowadays, most of the consumers prefer safe and tasty food without the use of agrochemicals. The progress of organic agriculture has increased the demand for cultivating lentil varieties in organic farming systems.

The aim of this study was the evaluation of chemical composition and physicochemical characteristics in three lentil varieties, and the comparison of their dietary value, when cultivated under organic or conventional farming systems.

Materials and Methods

Plant material

The genetic material used in this work consisted of 3 commercial lentil cultivars (Lens culinaris Medik.) provided by Fodder Crops and Pastures Institute (FCPI) (Larisa, Greece) and cultivated by a special group of farmers both in organic and conventional farming systems, at the same area in the territory of Larisa (Thessaly, Greece). The lentil cultivars were ‘Samos’, ‘Dimitra’ and ‘Thessalia’. Seed samples of lentil cultivars were taken from the above fields at the stage of seed maturity, having 12% of moisture.

Characteristics evaluated

For the evaluation of the physicochemical properties, a sample of 20g from lentil seeds was taken from each of the 5 replications (fields) of the experiment. The characteristics evaluated and the methods followed, are presenting below.

Seed density: After weighing, the seeds were placed in a volumetric cylinder and the increase in water volume was recorded. The seed density was calculated in gr/ml.

Seed density after a 24-hour hydration: The seeds were first soaked for 24 hours and then they repositioned in a volumetric cylinder.

Hydration coefficient: It was estimated as a percentage in seed mass increase after a 24-hour hydration.

Swelling coefficient: It was estimated as a percentage/ ratio of increase in seed water volume, before and after seed hydration.

Seeds’ pH: Weight of 4gr of seeds was used from each cultivar, and they were pulverized. They were added in 16ml of distilled water, where the pH was measured with a pH-meter (Hanna Instruments: PH/EC/TDS waterproof family).

Finally, the chemical analysis of the seeds, concerning their content in total nitrogen, phosphorus, potassium, calcium, magnesium, iron, zinc, manganese and boron, was conducted.

Statistical analysis

Multivariate statistical analysis was applied for every characteristic in order to determine similarities or differences among lentil cultivars in both organic and conventional farming systems. In addition, Analysis of Variance (ANOVA) and Principal Component Analysis (PCA) were conducted. Duncan’s test was used in order to estimate differences between pairs of means.

Results and Discussion

Overall, legumes are an important plant-based source of protein and provide significant benefits covering the essential elements for human consumption, such as phosphorus, calcium, magnesium etc. While promoting environmental and socio-economic sustainability [13,14]. Furthermore, nowadays, food security is an important decisive factor that could influence consumers’ eating habits. More specifically, according to research, consumers request for their nutrition locally grown and organic lentils [15]. However, further research is needed in order to investigate the nutritional values of the organic-produced lentils compared to the corresponding conventional ones. Additionally, lentil cultivars that could adapt well under organic cultivation conditions should have high yield, with excellent nutritional quality and physicochemical characteristics.

The results of our research for all physicochemical characteristics are presented in Table 1. Specifically, pH, seed density, seed density after 24-hour of hydration, the hydration coefficient, and absorption coefficient, were measured. Based on Analysis of Variance, and using Duncan’s test the mean values for pH, and coefficients related to hydration and absorption, were not differentiated significantly for p<0.05. Only in the characteristic of seed density was found statistically significant differences between the two farming systems. The lowest hydration and absorption coefficients were estimated for the cultivar ‘Thessalia’. ‘Samos’ also had a low absorption coefficient. These properties are crucial since low values negatively affect technological processing and consumer utilization of legume seeds [16]. In general, the farming system did not seriously affect most of the physicochemical properties of lentil cultivars.