IMPROVING NUTRITIONAL AND QUALITATIVE PROPERTIES OF WHEAT BREAD BY USING MALLOW ( MALVA NEGLECTA L.) LEAVES POWDER

This study was investigates the effect of adding different concentrations (1, 2, 3, 4, 5, 6, 7, 8) % of mallow ( Malva neglecta L.) leaves powder (MLP) to wheat bread mix on nutritional and qualitative properties of the obtained bread. Results of the chemical composition based by dry matter, moisture, ash, protein, fat, and carbohydrates for wheat flour and mallow leaves powder were 87.4, 12.6, 0.65, 10.5, 1.25, 75% and 96.2, 3.8, 7.90, 12.70, 1.60, 74.20 %, respectively. The study included nine treatments (T1, T2, T3, T4, T5, T6, T7, T8, T9 ), where T1 was the control treatment. During the fermentation period, dough mass was increased to its maximum value, T1 recorded the lowest height. The addition of (MLP) led to a slight increase in the specific volume of (T2, T3, T4, T5, T6), and this may be due to the increase in the proportion of polysaccharides in the mallow plant, while the specific volume began to decrease significantly in treatments (T7, T8, T9). Each of (T7, T8, and T9) showed significant differences as compared with the control treatment (T1) for the characteristics of color of crust, symmetry of form, evenness of bake, grain, color, texture of crumb, aroma, and taste. There were no significant differences between (T2, T3, T4, T5, T6) compared with T1. The results indicate that the consumer accepted T2, T3, T4, and T5 treatments as well as T1. GC analysis showed the presence of phenolic compounds in mallow leaves powder, such as phenol, 2-chlorophenol, 2-methyl phenol, 4-methyl phenol, 2-nitrophenol, 2,4-dimethylphenol, benzoic acid, 2, 4-Dinitrophenol (0.150, 0.036, 0.03, 0.127, 1.360, 0.042, 0.002, 5.552 mg\100g) respectively.


INTRODUCTION
Herbs and plants were used for thousands of years as traditional medicines to treat numerous diseases as anti-carcinogenic, antibacterial, anti-inflammatory, antiatherosclerotic, antitumor , and antimutagenic.Medicinal plants are a good source for a wide variety of natural products, such as the phenolic and flavonoid compounds which are very interesting for their antioxidant properties ( 3 ; 13 ; 4).Bread which made from refined white flour is a product with low concentrations of antioxidants, and due to its wide consumption all over the world, it can be considered an interesting way to supply it with functional supplements (13 ; 28).Dziki et al., (12 ; 4) reviewed current trends in enhancing baked wheat products by adding raw materials rich in phenolic antioxidants, such as grains, spices, herbs, fruits, and by-products of the food industry.However, few studies have focused on enriching these products with green portions of vegetables.Moreover, several studies have not taken into account consumer acceptance of fortified bread.Nowadays, there is an increasing global demand for foods fortified with natural antioxidants to improve overall health and reduce the risk of chronic diseases caused by oxidative stress.Foods rich in antioxidants play an essential role in preventing cardiovascular diseases, cancers, infections, and problems caused by skin aging.Plants are an inexhaustible source of functional and bioactive compounds and have been used for thousands of years for their preservative properties and also to enhance the flavor and color of food.Currently, incorporating these plants into the traditional food industry has become an interesting approach, which has greatly improved the potential of this food as a "preventive model" for disease prevention (3 ; 13 ; 17).
Malva neglecta L. ( family-Malvaceae ) is an annual, biennial, or perennial herb plant which is commonly known as cheese weed mallow.This genus is spread throughout the temperate, subtropical, and tropical regions of Africa, Asia, and Europe .M. neglecta has been widely used in several parts of the world for curing diverse diseases such as inflamed purulent wounds, boils, and swellings.A dried powder of leaves and roots is used to clean wounds and sores.Leaves and stems of M. neglecta contained different amounts of phenols, flavonoids, saponins, alkaloid, resin, and tannin (antioxidant potential).Moreover, this plant is used for the treatment of inflammation, pain, and liver injuries (3 ; 13).Wild mallow was used in the Middle East on a large scale as a source of food in times of war and periods of austerity and was known as Khubeiza or Tula in Arabic, and it is used as the main ingredient in a traditional Arabic dish called with the same name; and also in salads, soups and other dishes by the local Arab population.It is used in Turkey as a vegetable in various forms such as stuffing the leaves with bulgur or rice or using the boiled leaves as a side dish.The soaked (cooked) leaves are used to treat dysentery, constipation, and fever.Besides, the cataplasm of leaves is also used in the treatment of painful wounds and skin ulcers, this vegetable contains many important nutrients such as essential minerals, n-3 and n-6 fatty acids, and various terpenes with valuable biological properties.Moreover, this vegetable possesses important antioxidant activity thus can be used as a natural inexpensive and abundant source during the winter season to reduce cellular oxidative damage (24).In the present study, mallow leaves powder (MLP) was used to evaluate their effect as a functional ingredient for enhancing the Nutraceutical properties of baked wheat products.

MATERIAL AND METHODS Mallow leaves powder (MLP) preparation ;
The whole plant of mallow was harvested in February 2019 from the area of the University of Baghdad (Baghdad, Iraq).The leaves were separated, washed well, then dried in the shade for ten days at room temperature, then grind using a household grinder (Chinese type Cia Tronic).The powder was passed through a sieve No. 70 (250 μm) and stored in polythene bags at room temperature under a dry condition until use it (13).Bread(loaf) preparation; The bread-making were done using the straight dough according to AACC method No. 10-10 B (1 ; 21) with a slight modification.The bread formula for each loaf was included 100 g wheat flour, 1 g yeast, 1 g salt, 5 g sugar, 3 g fat, and an adequate amount of water to obtain dough of optimum consistency.The bread-making procedure was included mixing, at low speed for 2 min followed by a 9 min rapid mixing using spiral arm mixer, and a fermenting time of 120 min at 36•C and 70% relative humidity (r.h.) and baking for 20 min at 210•C. in a convection oven.Baked loaves were cooled down at room temperature for 60 min, wrapped in a plastic film, and then stored at room temperature (20˚ C), below the treatments used in this study; T1: Only the main components.

Sensory evaluation of bread (loaf) ;
The sensory properties (color, odor, taste, texture, and overall acceptability) of loaves were evaluated according to Almhyawi, (6) method by ( 8) panelists.pH measurement of flour and dough; AACC method 02-52 (1) was adopted by mixing 10 g of flour or dough with 100 ml distilled water (pH 7), then homogenized by German Heidolph Made at 2600 speed (r.p.m.) for 2 minutes and left for 5 minutes, then pH was measured.Chemical analysis of MLP ; All treatments and MLP were studied using the standard method AACC (1), , , (46-11), (01-8).Total carbohydrate was calculated by difference.

Estimation of phenolic compounds
Sample Preparation; Five grams of MLP was extracted by maceration using 100 ml of methanol and 0.1 % HCl.The mixture was placed on a magnetic stirrer for one hour, and separated using a centrifuge at 4000 r.p.m. for 10 minutes.The supernatant was concentrated using a rotatory evaporator, filtered and injected into the GC device.Bread staling tests Determination of the moisture content of bread crumb and crust; Crumb and crust moisture was measured adapting AACC (1) , (44-19) by taking 3gm bread crust and crumb individually, both were dried under 105 • C until constant weight.Determination of crumb swelling power (SP); SP of the crumb was measured according to Al-jelawi (5), two gm of bread crumb mixed with 10 ml distilled water (d.w.) for 30 min., then placed in a test tube for centrifugation at (3000× g / 5 min), the strength of swelling power determined according to the following equation: The crumb swelling power (SP) = D-(A+B) / B A= centrifuge tube weigh.B = sample weigh.D= residues tube weigh.Determination of crumb sediment volume in aqueous suspension (CVS) ; CVS was evaluated according to Al-jelawi(5), 5 gm of bread crumb was mixed with 50 ml d. w. for 15 min, then placed in the graduated cylinder and left for 2.5 hours until crumb portions were settled and leachate becomes clear, the CVS recorded in cm 3 .

Determination of antioxidant activity DPPH Radical-Scavenging Activity (RSA)
The RSA was measured according to (27) with some modulations.One ml of the sample (4 mg/ml) was mixed with 1 ml of DPPH solution (0.1 M).The mixture kept at the dark place at room temperature for 30 minutes and then centrifuged at 10,000 g for 5 min.The absorbency was measured at 517 nm, and the percentage of the scavenging activity was calculated according to the following equation Radical Scavenging activity A = [C -(B-A )/ C] x100 A= Spectrophotometer reading of the tested sample at517 nm wavelength.B = the absorbance of the control at 517 nm (prepared by mixing 1 ml of ethyl alcohol with 1 ml of the sample under study).=C = reading of the positive control at 517 nm (obtained from mixing 1 ml of DPPH with 1 ml of distilled water).Statistical analysis ; Statistical Analysis System (SAS) (26) was used for the analysis of data, to study the effect of different treatments in the studied traits in full randomized design (CRD).The differences between mean were compared with the least significant difference (LSD).

RESULTS AND DISCUSSION
Chemical composition of flour and mallow leaves powder: Table 1 show the chemical components percentages of the flour and mallow leaves powder.The percentage of moisture in the flour (Besler Brand) was 12.6%, which is within the favorites range of bakeries (11.5 -15.2%) and it helps in storing flour without damage.Moisture is an important factor in determining the quality of the flour and its water absorption.Almhyawi, (6) found that the moisture content in Iraqi wheat was (13.40%).The protein content was 10.5 %.These results were consistent with Al-jellawi (5) Who found that the percentage of protein in the Iraqi wheat was (10.27%) and ‫‬ Hussain et al, (15) Who found the protein content in the Iraqi wheat (8.54-11.40%).Fakhfakh et al, (13) indicated that the percentage of soft wheat protein ranged between 9-12%.The protein content of grains is a quality characteristic, and it the basic criteria for the quality of wheat grains, which depends mainly on the genetic factors of class, species, climatic, and agricultural conditions prevailing during the growth.The same table showed that the fat percentage was (1.25%).Several studies have confirmed the importance of flour fat in bread making and the rheological properties of the dough, despite their low concentration compared to other flour ingredients (13).Ash percentages for flour samples were 0.65%, which is similar to that report by Pozrl et al. (25).Ash content is associated with the quality of the milling process and it is a strong indicator for flour color and purity.The efficiency of the milling process is determined by knowing the flour content of ash which is mainly associated with the amount of bran in the wheat grain, ( usually 0.4-2.0%,calculated based on 14% moisture ) (14).Pozrl et al., (25) found that the percentage of carbohydrates in wheat were (65-75%), which is identical to what found in the flour of the treatments under study.Results are shown that the total chemical composition of the powder of mallow's leaves represented by, dry matter, ash, proteins, fat, and carbohydrates were (98.40, 7.90, 12.70, 1.60, 74.20%) respectively.Dry matter content depends on the structure of the plant tissue; for this reason, diversity in the dry matter content for different plant species is expected (19).Some authors reported that the dry matter content of mallow species were 23.1 % in M. sylvestris (22) and 20.3-20.9 % in M. neglecta (8).Total ash contents may be thought of as an indicator of mineral contents in the plant materials (23).The highest total ash content was determined in M. neglecta (15.6 %).A similar result was found for M. sylvestris (20.0 %) by Kaya et al. (18) (8; 9; 22; 30).This result is similar to our study.The ascorbic acid content of the mallow (M.neglecta species) was (83.5 mg/100g), while Demir, (11) found that the amount of vitamin C for the same type was 53.62 mg / 100 g. the other studies found that the amount of ascorbic acid of wild edible plants was more than what was mentioned above (23).

Table 1. Chemical composition of mallow leaves powder and flour
Determination of flour and dough Ph: Table 2 shows pH values in the flour and dough.The pH values for flour, mallow leaves powder were (5.71, 5.58) respectively.The results indicated that the highest pH values were seen at the preparation time, and ranged from 5.57-5.62,then these values decreased with the progress of the fermentation process for all treatments.Treatment (T3) shows the lowest value after 2 h.where it was (5.24) as compared with the other treatments, which reached to 5.41, 5.29. 5. 24 -------------M.neglecta (pH=5.71)-------------L The effect of mallow leaves powder on the dough volume during the fermentation process Table 3 shows the volume of the dough inside the fermentation vessels, the results indicate that the volume of the dough at zero time was 100 cm 3 for all treatments.During the fermentation process, the dough mass increased to its maximum value by the end of fermentation process (after 2 hours).Treatment T1 recorded the lowest height, it reached 550 cm 3 as compared with the other treatments (T2, T3, T4, T5, T6, T7, T8, T9 ) which reached to (600 -570 -575, 570, 570, 565, 560, and 560 cm3) respectively.During the fermentation stage, yeast causes some changes in the dough such as fermentation of sugary materials, production of some products such as carbon dioxide, alcohol, organic acids, and esters, changes in the pH level, and softening the gluten (2).These elements lead to a complex system.Carbon dioxide production leads to a rise in the dough, this depends on the effectiveness of the yeast and the availability of the basic materials, and absence of growth inhibitors (14 ; 16).--------58.41NS -L.S.D.

The effect of mallow leaves powder on the weight, size, and specific volume of the manufactured bread
Table (4) shows the effect of adding mallow on the weight, size, and specific volume of the manufactured bread.The results indicate an increase in the weight of experimental bread with an increase in the percentage of added mallow powder.This increase was not significant except for treatments T8 and T9 compared with the other treatments.It has been noticed that there were non-significant differences among the treatments (T1, T2, T3, T4, T5, T6, T7) in size character of the bread, as their values were (700, 740, 730, 730, 725, 700 and 680) cm 3 , respectively.While T8 and T9 treatments showed significant differences as compared with the other treatments, their values were 550 and 520 cm 3 .These results were reflected on the values of the specific volume (cm 3 / g) for the bread produced from the flour under study, as the differences were not significant among the specific volume values of all treatments except for the two treatments T8 and T9.The use of mallow leaves powder resulted in a steady decrease in the specific volume at all levels of addition.This decline is due to the decrease in the percentage of gluten in the mallow powder leaves mixtures.The results in Table 4 regarding the volume and specific volume of the bread agreed with the data reviewed by Fakhfakh et al, (13), who found a significant decrease in bread volume due to the increasing substitution level, which was expected because dough expandability was significantly reduced due to addition.

Sensorial characteristics of the experimental bread
Table 5. shows the internal and external characteristics of manufactured bread, including the specific volume, the color of the crust, evenness of bake, the symmetry of form, aroma, taste and the color, the grain and the texture of the crumb.It is noted that, the use of mallow leaves powder led to an insignificant increase in the specific volume in the treatments (T1, T2, T3, T4, T5, and T6), and this may due to the increase in the percentage of polysaccharide in the mallow plant.The specific volume began to decline significantly in the treatments (T7, T8, and T9) and this may be due to a decrease in the percentage of gluten in the mixtures of mallow leaves powder.T7, T8, and T2 treatments showed significant differences as compared with control treatment (T1) in the characteristics of the crust color , symmetry of form, aroma, taste, and the grain, color, and texture of the crumb.While non-significant differences were observed among treatments (T2, T3, T4, T5, and T6) with treatment T1 .It is noticed from the results that the receptivity to T7, T6, T8, and T9 treatments is lower as compared with T1, and this may be due to the decline in the sensory characteristics of the product because mallow leaves powder is not suitable for making bread alone.It can be concluded from the results above that 4% of mallow leaves powder can be added successfully to wheat flour to produce high quality bread while maintaining a high degree of consumer acceptability Table 5 7), when studying the concentration of phenolic compounds and carotenoids in the leaves, stems, and seeds of the mallow plant (Malva sylvestris L.) indicated that the concentration of phenolic compounds was higher in the extracts isolated from the leaves A high percentage of total polyphenols was found in mallow leaves being 24,123 ± 0.718mg GAE/g (31).While Conforti et al., (10) indicated that the phenolic content of mallow leaves was in the range of 28 ± 0.35 mg chlorogenic acid equivalent / g of dry matter.Whereas other authors found total phenolic 0.84% as Gallic acid (13; 27).From the above results, it can be concluded that the leaves of the mallow plant can be a promising source for fortifying bread with phenolic compounds.The antioxidant activity (DPPH Radical-Scavenging Activity (RSA)) was measured, and it was found that its value was ( 44.97% ) for mallow leaves extract, which is a good percentage.Effect of mallow leaves powder ( MLP ) on bread staling: Tables 7 shows the effect of adding 4% mallow leaves powder ( MLP ) on bread staling during different storage period at (20•C).The moisture content in the fresh bread is distributed continuously between the crumb and crust of the bread.During bread storage, the moisture is migrated from the crumb to the crust .With gradual loss of crumb moisture and reduction of soluble starch (recrystallization of starch), which is usually "high" in fresh bread, the staling of bread increases with the aging of the product (5 ; 6 ; 16).Table 7 elucidated gradual increase in the moisture content of the bread crust, during the storage period in both treatments, and reached the highest value after72 hours of storage in T2, being (26.15%).The results of statistical analysis showed a significant differences (p≤0.05) between both treatments through the storage periods.The swelling power of crumb for both treatments were significantly different , and decreased gradually through the storage period.This could be attributed to the starch's re-crystallization (It is a situation where the starch becomes less soluble in water) (5; 20).A gradual decrease in the volume of sediments were observed for both treatments as the storage period proceeded.The statistical analysis (p≤0.05) showed a significant differences in the volume of crumb sediment in the aqueous suspension during the storage periods of both treatments.It is noteworthy that the amount of soluble starch was decreases a long with the storage time of product storage, this is due to the re-crystallization of starch which causes a reduction in starch water solubility.From the results of the same table, we note that adding mallow leaves powder to bread has led to an increase in its shelf life due to the high percentage of saccharides in this plant.

CONCLUSION
Eating foods rich in antioxidants, in a balanced context of the diet, is associated with the prevention of many degenerative diseases.Thus, improving the functions and sensory properties of traditional foods such as bakery products is an interesting approach with respect to actual consumer demand.Mallow (M.neglecta) is an important medicinal herb and functional food, it is rich in bioactive compounds and presenting important biological properties.At a fortification level of 4%, it can be used as a functional ingredient to enhance the nutritional potential of wheat bread without altering its organoleptic capacity.
. Evaluation of internal and external sensory characteristics of experimental bread T1: Only the main components.T2: The main ingredients with added 1% Mallow leaves powder (MLP).T3: The main ingredients with added 2% MLP.T4: The main ingredients with added 3% MLP.T5: The main ingredients with added 4% MLP.T6: The main ingredients with added 5% MLP.T7: The main ingredients with added 6% MLP.T8: the main ingredients with added 7% MLP.T9: The main ingredients with added 8% MLP.* (P≤0.05).

Table 2 . pH values in the flour and dough of treatments under study
, 5.38, 5.39, 5.40,