Paniz Khaloo Kermani; Marzieh Moeenfard; Reza Farhoosh; Arminda Alves
Abstract
[1]Introduction: Date seed are considered as a valuable by-product from Phoenix dactylifera L. which played an important role in the economy and social life of the people of the Middle East and North Africa region. They consist mostly of carbohydrates, fatty acids and proteins as well as phenolic compounds. ...
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[1]Introduction: Date seed are considered as a valuable by-product from Phoenix dactylifera L. which played an important role in the economy and social life of the people of the Middle East and North Africa region. They consist mostly of carbohydrates, fatty acids and proteins as well as phenolic compounds. Despite the presence of various beneficial bioactive compounds, they are usually discarded or are utilized as animal fodder. Therefore, explore the effective methods to incorporate date seeds in the human diet is a great of interest. Roasting provides a low cost and easy approach to add value to these wastes as roasted date seed powder is being used in the Arabian region to make “date seed coffee”. However, along with color and aroma changes, carcinogenic substance such as acrylamide may also formed during the roasting process. To date, no data have been published on the analysis of acrylamide in the roasted date seeds and respective brews. Therefore, the objective of the present study was development of an analytical method for determination of acrylamide in various date seeds varieties and their respective moka brews for the first time. Besides, other parameters related to the roasting process such as the color parameters and melanoidins content were also determined and compared with values obtained from Arabica coffee. Materials and methods: For this purpose 5 different varieties of roasted date seeds including Shahani, Zahedi, Kabkab, Mazafati and Estamaran as well as Arabica coffee were used for coffee brewing. For acrylamide determination in solid samples, they were firstly extracted using hot deionized water. Afterwards, 5 mL of sample (extract or coffee brew) was placed in a 15 mL falcon and extraction solvents including acetonitrile (10 mL), hexane (5 mL) along with 1 g of NaCl and 4 g of MgSO4 were added. After mixing on vortex for 1 min and centrifugation (5 min, 5000 rpm), 2 mL of the supernatant was cleaned using appropriate combination of sorbents (100 mg PSA, 50 mg C18 and 50 mg SAX) along with 0.30 g of MgSO4.The cleaned supernatant was filtered and analyzed using high-performance liquid chromatography coupled with a photodiode array detector (HPLC-PDA) at 202 nm. The injection volume was 20 μL. The chromatographic separations were performed on a Eurospher 100-5 C18 column (250× 4.6 mm). Optimization was performed according to the type of organic solvent (acetonitrile and methanol), the percentage of organic solvent in the mobile phase (10, 5, 3% v/v) and the flow rate (0.1, 0.7, 0.5 mL/min). The color parameters (using photography and help of ImageJ software) and melanoidin content (spectrophotometrically at 420 nm) were also determined. Results and discussion: The results indicated that the water/acetonitrile with a ratio of 97:3 and a flow rate of 0.7 mL/min permitted the acceptable separation of the acrylamide peak from the interfering compounds. The LOD and LOQ of optimized analytical method were 9.1 and 30.62 µg/kg, respectively. The suggested HPLC/PDA method is promising for analysis in order to guarantee the quality control of acrylamide. The presence of acrylamide in all roasted date seeds was observed. Accordingly, acrylamide content in Arabica coffee (1825.23± 17.44 µg/kg) was significantly higher than those obtained from date seeds varieties. The amount of acrylamide in different types of date seeds varied from 360.99± 4.15 to 129.43± 2.37 µg/kg, being Kabkab and Mazafati as the highest and lowest values, respectively. Moka brews prepared from roasted date seeds demonstrated the presence of acrylamide in the range of 25-68 µg/L. The highest level of melanoidin were observed in Arabica coffee followed by Shahani, Zahedi, Kabkab, Mazafati and Estamaran, respectively. In the most cases, an inverse relationship was observed between the acrylamide and melanoidin content in roasted date seeds. For example, Shahani had low acrylamide and high melanoidin content. The study of color parameters revealed that the parameters a* and b* largely follow the pattern of melanoidin, so with increasing the amount of a* and b*, the amount of melanoidin also increased in the samples.
Food Chemistry
Farideh Mojrian; Marzieh Moeenfard; Reza Farhoosh; Hadi Mahdavian Mehr
Abstract
Introduction: Date seeds (also known as pits and kernel) are among the most important wastes which are generated during direct consumption or from the date processing industries. Despite the presence of several nutrients and bioactive compounds and their subsequent beneficial health effects, these by-products ...
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Introduction: Date seeds (also known as pits and kernel) are among the most important wastes which are generated during direct consumption or from the date processing industries. Despite the presence of several nutrients and bioactive compounds and their subsequent beneficial health effects, these by-products are frequently discarded to use as soil fertilizer or as feed for livestock. Roasting opens a cost-effective way to include date seed in the human diet. The aqueous extract of roasted date seed represented a coffee-like beverage. Date seed coffee has a relatively low acceptance among consumers and is usually supplemented with a variety of additives to improve the taste. Therefore, due to rising the global coffee price, in the present studywe aimed to substitute Arabica beans with roasted date seeds in order to make a coffee beverage similar to Coffea Arabica boiled coffee brew. Results and Discussion: Substitution with roasted date seed resulted in lower lipids, protein and caffeine of coffee brews as the values were decreased from 330.67, 956.75, 76.51 mg/100 mL in Coffea Arabica (100%) to 192.61, 149.00, 45.59 mg/100 in date seed coffee (100%), respectively. Higher amounts of date seed also resulted in lower pH and acrylamide content. Accordingly, pH was decreased from 5.7 in D100 to 4.4 in A100. Acrylamide content was attenuated from 5.06 µg/100 mL in A100 to 1.71 µg/100 mL in D100. Reduction in viscosity was also observed from 0.93 (A100) to 0.86 mPa.s (D100). The mean value of the color parameter including L*, a* and b* in the 100% Coffea Arabica brew was more than the 100% date seed coffee, which indicated that the coffees brewed from date seeds in different proportions were brighter and had higher red and yellow color parameters. Substitution with date seed had less effect on the total phenol content as TPC of coffees ranged from 28 to 42 mg/100 mL for 100% date seeds brew and Coffea Arabica brew, respectively. On the other hand, the flavonoid content (TFC) of coffees was significantly affected by the amount of date seeds (5 to75 mg/100 mL for 100% date seeds and Coffea Arabica brew, respectively). All brews have high antioxidant activity. For DPPH the highest results (88/9 %) were obtained in the coffee brewed from 100% date seeds, while the FRAP value it was vice versa. The results of sensory evaluation indicated a high similarity among A100 and D10 coffees as parameters such as aroma, color and texture (concentration) of coffee were evaluated appropriate. The results also showed that substituting Coffea Arabica up to 35% with roasted date seeds can improve the overall acceptance of the coffee brews by reducing bitterness.Conclusion: In general, the ability to replace Coffea Arabica with date seeds up to 10 and 35% was reported acceptable in terms of sensory characteristics, as the color and aroma were similar to 100% Coffea Arabica. Besides that due to reduced bitterness, the overall acceptance were almost high.
Reza Farhoosh; Mohammad Shahedi; Ali Sharif
Abstract
The best PH for getting Millard reaction started and Acrylamide formation ranges 7 to 8. PH below the range slows the reaction speed down and the resultant Acrylamide formation delayed. This research assess how Acetic Acid in 0.05, 0.15, 0.25% concentrations together with sourdough may promote acidity ...
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The best PH for getting Millard reaction started and Acrylamide formation ranges 7 to 8. PH below the range slows the reaction speed down and the resultant Acrylamide formation delayed. This research assess how Acetic Acid in 0.05, 0.15, 0.25% concentrations together with sourdough may promote acidity in bread dough and how they can cause a reduction of acrylamide content in Sangak bread [an Iranian traditional bread]. Here the acrylamide is assessed after it was derived and then transferring it to gaseous chromatography with ion indicator. The concentration of acrylamide in Sangak breads made of sourdough with 0.05, 0.15 and 0.25% of acid acetic showed a decrease of 73.47, 81.50 and 82.10% and also a 90.55, 92.80 and 95.96 % decrease when the bread has been made of the same compounds and yeast. The acidity of compounds with acidity rate of 0.05, 0.15 and 0.25% in Sangak bread made of yeast equates to 0.12, 0.14 and 0.17% (normal) respectively; while these values for Sangak breads made of sourdough stand at 0.16, 0.18 and 0.21% (normal). Therefore, decreased acrylamide can be attributed to increased acidity of dough.
