Utilization of guava seeds [Psidium guajava L.] in some food products

ANALYSIS of guava seed powder revealed that guava seed contained ether extract 7.97%, protein 9.37%, crude fiber 57.6%, dietary fiber 79.37%, lignin 20.37%, cellulose 41.28% and hemicellulose 17.7%. The characteristics of guava seed oil were, acid value 0.85 mg [KOH/g oil], peroxide value 1.15 [meq O[2]/kg oil], saponification value 185.23; unsaponifiable matter 1.21% and iodine value 119.5 [g I[2]/100g oil]. Moreover, the most abundant saturated fatty acid was palmatic. However, the most predominant unsaturated fatty acid was linoleic acid which indicates that the oil is considered as semi drying oil. With regard to protein evaluation of guava seed, results showed that leucine was the predominant essential amino acid with a value of 2.2 [mg/g], while the predominant non-essential amino acid was glutamic acid 6.2 [mg/g]. Biological value of guava seed protein was 56.96 and PER was 0.32. Addition of guava seed powder to rice grits for extrusion caused reduction of the expansion ratio [ER], decrease in the bulk density [BD], slight increase of the water absorption index and decrease in the breaking strength [BS] of the extrudate. The sensory evaluation of the new products indicated that good extrudates were obtained by adding up to 8% of guava seeds powder to rice grits. Adding guava seed powder to semolina flour to produce high fiber macaroni caused decrease in the BS values. The results obtained showed that the absorbed water and solid substance were increased as the level of addition of guava seed powder was increased. The sensory evaluation indicated that macaroni product with excellent and very good grade could be obtained by adding guava seeds powder up to 12%

Preparation and protein-fortification of date bars

To increase the utilization and tile nutritional value of the fruis, of Hayani date cultivar: the most dominant among date cultivars grown in the north eastern sector of Egypt, the fruits were minced, dried and formulated into date bars. Also, the prepared bars were fortified using casein, skim milk powder, sesame, soybean and chickpea flours [3, 5, 7 and 10% of total weight]. The prepared date bars were evaluated for colour, texture, yield and protein content. Sensory properties of the products were also evaluated and compared to the unfortified plain bars. In addition, the proximate composition, the mineral content and the amino acids profile of the fortified [5%] bars were carried out. Data obtained indicated that the prepared plain date bars and the bars fortified to 5% level were organoleptically acceptable. Meanwhile, coating the bars fortified with higher Ievels [7-10%] of the additives with chocolate increased the overall acceptability of the product. The data also revealed that fortification, as expected increased the protein content [from 3.5 to 12.2%] while slight changes in texture and colour of the fortified product were noted. In addition, proximate composition varied according to the fortification source. Total and reducing sugars and crude fibers were slightly decreased, while the ash content was relatively increased. All amino acids including the essential ones were considerably increased in the fortified bars with casein or skim milk powder. These findings indicate that the Hayani dates can be processed into acceptable date bars with improved nutritional profile by fortification using casein, skim milk, soybean or chickpea flour. The application of this process may increase the utilization of Hayani date fruits, which have low eating quality in the fresh unprocessed form, and provide the consumer with date products of high nutritional value

Some valuable compounds from prickly pear seeds and peels

Chemical properties of crude prickly pear seed oil were: acid value 0.63% [mg KOH/g oil], peroxide values 1.65 [meq o[2]/kg oil]; saponification value 188.41, unsaponifiable matter 1.36%, and iodine value 108.26 [g[2]I, /100g oil]. Moreover, palmitic acid was the major saturated fatty acid, while lenoleic acid was the major unsaturated fatty acid in crude oil of prickly pear seed. The biological value [BV] of prickly pear seed was 49.16 and the PER 0.07. The obtained results showed that pectin extracted from peels of ripe prickly pear had higher ash content [2.61 and 2.12%] than that extracted from peels of mature prickly pear [1.59 and 1.05%]. Anhydrogalacturonic acid content was higher in pectin extracted from fresh and dried peels of ripe prickly pear [50.93 and 5 I.12] than that extracted from fresh and dried peels of mature prickly pear [48.98 and 48.30], respectively. Methoxyl percentage of pectin extracted from peels of ripe prickly pear had higher value than the methoxyl percentage of pectin extracted from peels of mature prickly pear. Acetyl content of pectin extracted from peels of ripe prickly pear was slightly higher than that extracted from peel of mature prickly pear. Degrees of estrification [DE] of pectin extracted from ripe prickly pear peels were 31.49% for fresh peels and 34.93% for dried peels. Meanwhile, it was 25.67% for pectin extracted from fresh peels and 26.84% for dried peels of mature prickly pear. The results indicated that there were no significant differences in the viscosity values [at 10 rpm] between pectin extracted at different maturity stages [mature and ripe] or pectin obtained by different extraction methods [fresh and dry]