Fermented food is one of the first processed food products consumed by humans and it was originally a means of food preservation and was first used more than 7000 BC in the Neolithic period in East Asia [1]. One of the first types of fermentation was alcoholic drinks and cheese, then it developed into fermented milk, pickles, halon and vinegar, which was formerly known as acid wine and butter and the fermentation process was previously done naturally by means of molds and yeasts in the air, or the surrounding environment. The fermentation process improves the nutritional, functional and sensory value of foods such as yogurt, broth and sausages and many fermented foods and beverages contain live precursors such as probiotics that bring health benefits to the host when consumed live and are called biofortified foods [2]. One type or mixture of precursors is added to it, which has well-known health benefits by stimulating the growth of probiotics, or as a functional food. As for the combination of probiotics and prebiotics in one food, the product is called a synergistic food [3]. The production of almonds in the United States of America in 2016 amounted to (2.2) million tons and the price of one pound was 2.84 dollars [4]. Almonds are among the most important types of nuts bearing within their chemical composition of precursors with many health, preventive and curative benefits and its use in bio-synergetic foods is a promising matter of interest due to the health benefits of bio-enhancers and bio-precursors [5].               

Milk Source 

Milk samples were collected from a herd of cows belonging to one of the breeders in the Al-Alam area, east of the city of Tikrit/Salah al-Din. Clean, sterile glass bottles were used for packing and transporting the milk to the laboratory and placing it in the refrigerator at a temperature of (4) °C. The White Side Test was used to ensure that the milk was safe and free of mastitis and as in the narrator the formation of a precipitate or jelly or both was evidence of an infection of the udder.

Preparation of Almond Milk

Almond milk was prepared according to what was mentioned by Al Tamimi [4], with some modifications. After cleaning the almonds were soaked in distilled water weight/volume in a ratio of 3:1 almonds: water for 48 hours at room temperature, then the almonds were washed and put in the electric mixer, add the distilled water, the proportions of almonds: Water 4:1. The mixing process was conducted for 5 minutes, then the product was filtered to separate the solids and then the resulting almond milk was sterilized at a temperature of 121 °C for 5 minutes, cooled and kept in the refrigerator in tightly closed containers; To carry out the examinations and subsequent transactions.

Chemical Tests of Milk

The proportions of fat, protein and lactose were estimated using the (Lactostar) device, while the percentage of ash and pH in milk were estimated according to what was stated in A.O.A.C [6] and the method described in Javai et al. [7], was used to measure the percentage of total acidity.

Microbial Examinations of Milk

The number of total bacteria was estimated by the method of poured plates, as stated in Frank and Yousef, [8] and the number of bacteria of the colon group and the numbers of yeasts and molds were estimated as reported in the American public health [9] and the method used in Chen et al. [10], was used. To estimate the numbers of lactic acid bacteria.

Statistical Analysis

The results of the experiments were analyzed using the Linear Model General within the ready-made statistical program SAS [11], to study the effect of factors on according to the complete random design (CRD). studied at the level (0.05).

Chemical Composition of Almond Milk Fortified With Probiotics

Moisture: The results of the statistical analysis shown in Table 1 show the effect of adding probiotics to almond milk. It is noted from the results that the percentage of moisture in the milk of the treatments (T1, T2, T3, T4) immediately after manufacturing was (88.84, 88.81, 88.85, 86.53) %, respectively. No significant decrease was observed for the treatments (T4, T3, T2) after 7 days of storage. While it was shown from the table that the process of storing milk at refrigerator temperature led to a significant decrease at the probability level (p<0.05) in the moisture content after 14 days of storage, as its values ​​for the treatments (T1, T2, T3, T4) were at 88.66, 88.63, 88.65, 85.89%, respectively.

Table 1: Effect of Different Treatments and Storage Period On the Percentage of Moisture (%)

The numbers in the table represent the mean values ​​± standard deviation. - The different letters in the same row indicate the presence of significant differences at the level (p≤0.05). T1 = Yogurt T2 = Almond Milk and Yogurt Paddy T3 = Almond Milk, L. bulgaricus and Lactobacillus acidophilus T4 = Almond Milk, Bifidobacterium longum and Lactobacillus acidophilus

These results are in agreement with the findings of Yilmaz-Ersan and Topcuoglu [12], who indicated that the moisture content of almond milk is higher than that of yogurt and these results were similar to what Bahrami et al. [13], found that the moisture content of full-fat yogurt is 87.22 % and the results show a decrease in the percentage of moisture during storage, as the values ​​ranged after 14 days of storage at a temperature of (2±5 ° C) for yogurt and almonds between 85.89 and 88.66% and this is consistent with what Qureshi et al. [14], found. Those who indicated a decrease in milk moisture from 84.78 to 84.65% during the storage period of 15 days and they attributed the reason for this decrease to a little evaporation during storage.

Fat

Table 2 shows the effect of adding probiotics to raw milk and almond milk, as it appears from the results that the percentage of fat in the milk of the treatments (T1, T2, T3, T4) immediately after manufacturing was (3.20, 2.07, 2.09, 2.04) %. Straight. It is noted from the results that storage at a temperature of 5±2°C for 7 days did not show any significant differences in treatments T2, T3 and T4, while a significant increase occurred in treatment T1. The table also shows that storage in the refrigerator temperature for 14 days did not lead to significant differences in the percentage of fat in treatments T2, T3 and T4, as it reached (2.13, 2.12, 2.10) %, while there was a significant increase in the T1 treatment, which amounted to (3.36) %.

Table 2: Effect of Different Treatments and Storage Period On the Percentage of Fat (%)

The numbers in the table represent the mean values ​​± standard deviation. - The different letters in the same row indicate the presence of significant differences at the level (p≤0.05). T1 = Yogurt T2 = Almond Milk and Yogurt Paddy T3 = Almond Milk, L. bulgaricus and Lactobacillus acidophilus T4 = Almond Milk, Bifidobacterium longum and Lactobacillus acidophilus

These results were in agreement with the findings of Yilmaz-Ersan and Topcuoglu [12], where they indicated that the percentage of fat in almond milk was less than the percentage of fat in yogurt, reaching 2.1 and 3.3%, respectively. Sengupta et al. [15]. The results also showed an increase in the percentage of fat during the storage period, so the values ​​after 14 days of manufacturing ranged between 2.10 and 3.36% for the manufactured products and that this increase coincides with the gradual decrease in moisture during storage. This study also agrees with the findings of Khattab and Dosh [16], who indicated that there was a slight increase in the percentage of fat in milk and attributed this to the low percentage of moisture, which led to an increase in the percentage of total solids.

Protein

Table 3 shows the effect of adding probiotics on the percentage of protein in raw milk and almond milk, as it appears from the results that the percentage of protein in the milk of the treatments (T1, T2, T3, T4) immediately after manufacturing was (3.46, 1.60, 1.58, 1.60%)%, respectively. It appears from the results that storage at a temperature of 5±2°C for 7 days did not show any significant differences in treatments T2, T3 and T4, while a significant increase occurred in treatment T1. It is noted from the table that storage in the refrigerator temperature for 14 days led to significant differences in the percentage of fat in treatments T1, T2, T3 and T4, which amounted to (3.61, 1.69, 1.65, 1.70) %, respectively.

Table 3: Effect of Different Treatments and Storage Period On the Percentage of Protein (%)

The numbers in the table represent the mean values ​​± standard deviation. - The different letters in the same row indicate the presence of significant differences at the level (p≤0.05). T1 = Yogurt T2 = Almond Milk and Yogurt Paddy T3 = Almond Milk, L. bulgaricus and Lactobacillus acidophilus T4 = Almond Milk, Bifidobacterium longum and Lactobacillus acidophilus

These results were in agreement with the findings of Yilmaz-Ersan and Topcuoglu [12], as they showed that the percentage of protein in almond milk was less than the percentage of protein in yogurt (1.54 and 3.43%, respectively) and these results also agree with what Qureshi indicated. and others [14], who indicated a high percentage of milk protein during the 15-day storage period and they attributed the reason for this to the low percentage of moisture, which led to an increase in the percentage of total solids.

Ash

The results of the statistical analysis in Table 4 show the effectiveness of adding probiotics on the percentage of ash in raw milk and almond milk. It is noted from the results that the percentage of ash in the milk of the treatments (T1, T2, T3, T4) immediately after manufacturing was (0.68, 2.89, 2.85, 2.88) %, respectively. It appears from the results that storage at the refrigerator temperature for 7 and 14 days led to significant differences in treatment T1 whose values ​​were at 0.76 and 0.81%, respectively. While it is noted from the table that storage in the refrigerator temperature for 7 and 14 days did not lead to significant differences in the percentage of ash in treatments T2, T3 and T4, whose values ​​were (2.92, 2.87, 2.91, 2.95, 2.90, 2.94) %, respectively.

Table 4: Effect of Different Treatments and Storage Period On the Percentage of Ash (%)

The numbers in the table represent the mean values ​​± standard deviation. - The different letters in the same row indicate the presence of significant differences at the level (p≤0.05). T1 = Yogurt T2 = Almond Milk and Yogurt Paddy T3 = Almond Milk, L. bulgaricus and Lactobacillus acidophilus T4 = Almond Milk, Bifidobacterium longum and Lactobacillus acidophilus

This result is in agreement with what was indicated by Yilmaz-Ersan and Topcuoglu [12], which showed that the ash percentage in almond milk was higher than the ash percentage in yogurt and this result was close to what was found by Stijepic et al. It is also noted that there was a rise in the percentage of ash during the storage period, so the values ​​after 14 days of manufacturing were 0.81% for yogurt on, due to the decrease in the percentage of moisture and the increase of total solids in the samples during storage. This result is consistent with what was found by Khattab and Dosh [15], who They indicated a high percentage of ash in milk with the progression of storage period.

pH

Table 5 shows the effectiveness of adding some probiotics to raw milk and almond milk, as it appears from the results that the pH value in the milk of the treatments (T1, T2, T3, T4) immediately after manufacturing was at (4.58, 4.65, 4.63, 4.69) respectively. It appears from the results that storage at a temperature of 5±2°C for 7 days led to significant differences at the probability level (p<0.05) in all treatments (4.41, 4.44, 4.45, 4.45), respectively. It is also noted from the results that the pH values ​​decreased with the progression of the storage period and the values ​​were after 14 days of manufacture (3.95, 4.07, 4.00, 4.09), respectively.

Table 5: Effect of Different Treatments and Storage Period On The PH Value

The numbers in the table represent the mean values ​​± standard deviation. - The different letters in the same row indicate the presence of significant differences at the level (p≤0.05). T1 = Yogurt T2 = Almond Milk and Yogurt Paddy T3 = Almond Milk, L. bulgaricus and Lactobacillus acidophilus T4 = Almond Milk, Bifidobacterium longum and Lactobacillus acidophilus

This result is consistent with the findings of Yilmaz-Ersan and Topcuoglu [12], who indicated that the pH of almond milk was 4.63 after processing and the pH of yogurt was 4.59, as well as what was found by Ibrahim [16]. The reason for this is due to the continued activity of the initiator bacteria during storage, but slowly [15]. This may be consistent with what was mentioned by Donkor et al. [17], who indicated a decrease in the pH value of therapeutic milk during refrigerated storage at 4°C for three weeks. These results were also in agreement with what Hussan et al. reported, as they noticed that the pH value decreased significantly during storage of almond milk in refrigerator temperature for 7 days and 14 days. The reason for this was attributed to the activity of microorganisms that cause the fermentation of lactose sugar and the production of acetic acid, formic acid and lactic acid and thus cause a decrease in the pH value.

Total Acidity

The results of the statistical analysis show in Table 6 the effect of adding probiotics on the percentage of total acidity (calculated on the basis of lactic acid) in raw milk and almond milk. It is noted from the results that the percentage of acidity in the milk of the four treatments (T1, T2, T3, T4) immediately after manufacturing it was at (0.84, 0.80, 0.81, 0.78) %, respectively. It appears from the results that storage at refrigerator temperature for 7 days led to significant differences in all different treatments, as their values ​​were at 0.93, 0.88, 0.86 and 0.84 percent, respectively. The table also shows a decrease in the total acidity values ​​with the progression of the storage period and the values ​​after 14 days of manufacture were (1.05, 0.96, 0.95, 0.91) %, respectively.

Table 6: Effect of Different Treatments and Storage Period On the Percentage of Total Acidity (%)

The numbers in the table represent the mean values ​​± standard deviation. - The different letters in the same row indicate the presence of significant differences at the level (p≤0.05). T1 = Yogurt T2 = Almond Milk and Yogurt Paddy T3 = Almond Milk, L. bulgaricus and Lactobacillus acidophilus T4 = Almond Milk, Bifidobacterium longum and Lactobacillus acidophilus

This result is consistent with what was found by Yilmaz-Ersan and Topcuoglu [12], who indicated that the acidity value of sapphire milk was 0.85% and that of almond milk was 0.80%. One day after manufacturing, it was 0.85%. It is also noted from the results that the total acidity values ​​increased during the storage period and the values ​​were after 14 days and the reason for this is attributed to the continued activity of the initiator bacteria during storage. for three weeks. The results were also consistent with what Hussan et al. mentioned, as they noted that storing almond milk at refrigerator temperature for two weeks led to a significant increase in the total acidity value by 14% and the reason for this was attributed to the activity of most microorganisms that have the ability to Fermentation of lactose sugar and production of lactic acid.

Bacteriological Examinations of Milk Produced

Table 7 shows the results of the estimation of microorganisms, which included the total number of bacteria, the number of coliform bacteria, the number of lactic acid bacteria, the number of yeasts and molds for yogurt and almonds stored for 14 days at a temperature of (2±5) °C. From the results in the table, it is clear that the total number of bacteria immediately after manufacturing was 104 x 68, 104 x 57, 104 x 53 and 104 x 50. T. m/g of milk for the treatments T1, T2, T3 and T4 respectively and this result is consistent with what was found by Al-Jubouri [1], which indicated that the total number of bacteria in yogurt was higher than the therapeutic milk (104 x 58 and 104 x 64) and T. m/gm, respectively. We also find that the number of bacteria began to decrease during cold storage, as it was after 14 days of storage in the refrigerator 104 x 60, 104 x 56 and 104 x 53 W.T.m/g for the treatments (T4, T3, T2) respectively and the reason is due In this gradual decrease, the accumulation of secondary metabolites produced by bacteria, which has an inhibitory effect on bacterial growth, as well as the increase in milk acidity, as the high percentage of lactic acid leads to a decrease in the number of microorganisms [18].

Table 7: Effect of Different Treatments and Storage Period On the Microbial Content (Wtm/Gm) Of Processed Milk

The numbers in the table represent the mean values ​​± standard deviation. - The different letters in the same row indicate the presence of significant differences at the level (p≤0.05). T1 = Yogurt T2 = Almond Milk and Yogurt Paddy T3 = Almond Milk, L. bulgaricus and Lactobacillus acidophilus T4 = Almond Milk, Bifidobacterium longum and Lactobacillus acidophilus

We also note from the results shown in Table 7 that there were no colon bacteria growths immediately after manufacturing, as well as no growths appearing after 14 days of storage. No growths appear after two weeks of storage. As for the numbers of lactic acid bacteria in yogurt, almond milk and various probiotics stored for 14 days at a temperature of (2±5) °C, it is noted from the results that the numbers of lactic acid bacteria immediately after manufacturing were 104×30, 104×38 and 104× 38 and 104 x 40 WC/gm for the four treatments. These results are consistent with the findings of Al-Jubouri [1], that the numbers of lactic acid bacteria in therapeutic milk were higher than that of yogurt. The results show a decrease in the number of lactic acid bacteria during storage. The values ​​after 14 days of storage at a temperature of (2±5) °C for treatments T1, T2, T3 and T4 were at 104 x 45, 104 x 48, 104 x 50 and 104 x 51. This is in agreement with what Donkor et al. [17], reported that all the probiotic bacteria strains that were stored by cryopreservation at 4° C for 28 days had their viability at the level required to have a therapeutic effect of 610 UTM/ml in The end of the storage period and some of these strains exceeded the number 710-810 WTm/mL. This is consistent with what Shin et al. [19], also mentioned that milk used with Bifidobacteria and other species and stored at 4°C for three weeks should contain bacteria numbers greater than 106 WTM/mL. It is noted from the table that some samples had a slight increase in the number of bacteria in the first week of storage compared to time zero and this may be due to the cells being active and to the availability of raw materials necessary for the activity and vitality of the cells and the lack of metabolic products that limit or prevent the growth of bacteria. The reason for the decrease at the end of the second week is the accumulation of secondary metabolites produced by bacteria, which have an inhibitory effect on bacterial growth, such as bacteriocins and organic acids [20]. As for the preparation of yeasts and molds for yoghurt and sapphire milk stored in the refrigerator for 14 days, no growths appeared during the duration of the experiment.

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