Recovery of caprine whey protein and its application in a food protein formulation

Evaluation of Cellular Responses by Chlamydomonas reinhardtii in Media Containing Dairy-Processing Residues Derived from Cheese as Nutrients by Analyzing Cell Growth Activity and Comprehensive Gene Transcription Levels

Utilities of whey powder (WP) and whey protein concentrate 34% powder (WPC34) prepared as dairy-processing residues were evaluated using a green alga Chlamydomonas reinhardtii. Analysis of C. reinhardtii growth showed that the strain used WP and WPC34 as nitrogen sources. Its specific growth rate and maximum cell density in WP-containing medium were higher than those in WPC34-containing medium; growth with WPC34 was improved by adding KCl or K2HPO4, which content was decreased as a result of WPC34's preparation from WP. Although the lipid contents in media containing dairy-processing residues were 2.72 ± 0.31 wt% and 2.62 ± 0.20 wt% with no significant difference, the composition ratio of fatty acid C14 with WPC34 was higher than that with WP and the composition ratio of the sum of fatty acid-C16 and -C18 with WPC34 tended to be lower than that with WP. Additionally, analyses of gene transcription showed that the transcription level of acetyl-CoA carboxylase biotin carboxyl carrier protein in WPC34-containing medium was lower than that in WP-containing medium, possibly affecting the ratios of the chain lengths of fatty acids. The transcription of genes involved in glycolysis and the TCA cycle was outstandingly lower in algae grown in WPC34-containing medium when compared to those cultivated in the presence of WP, resulting in differences in energy production for cell proliferation.

The enzymatic modification of whey-proteins for spray drying encapsulation of Ginkgo-biloba extract

Ginkgo biloba extract (GBLE) contains many bioactives including flavonoids and terpene trilactones that play some pharmacological roles. These compounds are sensitive to operating conditions; so, encapsulation is a suitable approach to protect them. In this study, different carriers including maltodextrin (MD), and its combination with gum-Arabic (MD-GA), whey protein concentrate (MD-WPC), and whey-protein hydrolysate (MD-HWPC) were used to encapsulate GBLE. Powder production yield, physicochemical/functional characteristics, physical stability and flowability of particles were affected by the type and composition of carriers. FTIR results indicated the placement of phenolic compounds in the carrier matrix. The SEM images also showed the morphological changes of particles (especially the size, indentation and surface shrinkage) under the influence of various carriers. Microencapsulated powders formulated using MD-HWPC showed the highest values of TPC, DPPH, and ABTS and a lighter color which determined the suitability of this wall material (due to the improvement of surface activity and emulsifying properties of protein as a result of partial enzymatic hydrolysis) to protect the antioxidant properties of GBLE during spray-drying, improving the production yield and preserving physical and functional characteristics of the encapsulated powders.

Effects of blending ratios and baking temperature on physicochemical properties and sensory acceptability of biscuits prepared from pumpkin, common bean, and wheat composite flour

The utilization of vegetables with supplementation of cereals and pulses plays a vital role in improving protein-energy malnutrition and micronutrient deficiency. Therefore, the study aimed to develop biscuits from pumpkin, common bean, and wheat composite flour with better physicochemical properties and sensory acceptability. All quality parameters were evaluated by using an official standard procedure. The results showed a significant (p < 0.05) difference among products. The addition of pumpkin and common bean flour to composite biscuits significantly (p < 0.05) increased the protein (9.44-16.16%), fat (17.03-21.42%), ash (1.72-2.08%), and crude fibre (1.37-2.06%) contents. In addition, the biscuit's lightness decreased as the incorporation of pumpkin and common bean increased. However, the redness and yellowness of the sample increased. Sensory evaluation scores indicated that biscuits supplemented with 10% pumpkin, 15% common bean, and 75% wheat composite flour baked at 200 °C were more preferred than other formulated products. Therefore, substituting pumpkin powder with wheat-common bean flour significantly improved the nutritional content of the biscuit with desirable sensory acceptability. The findings also showed that the developed products are essential in improving dietary diversity and food insecurity among low-income families.

Impacts of Pretreatment Techniques on the Quality of Tuber Flours

Besides dietary sources of energy, roots and tuber crops can also serve as functional foods and nutraceutical ingredients to be explored in disease risk reduction and wellness. However, they are easily spoiled because of their high moisture contents and enzymatic reactions. Therefore, this review aimed at gathering information on the effects of various pretreatment methods on the quality of tuber crops before converting them into flour. Studies reported by different scholars showed that there were significant differences in physicochemical and functional properties between untreated tuber and the treated tuber samples. The review also highlighted that the chemical treatment methods, particularly sulfite treatment, could increase the lightness value of the flour. In addition, blanching could induce a decrease in protein, ash, and fat. Despite this, blanching pretreatment techniques increased moisture and carbohydrate content. Chemical treatment increases the ash content, which might be responsible for chemical diffusion into the sample. The reviewed results showed that the application of different pretreatments on tuber crops significantly improves many quality characteristics such as color, fiber content, carbohydrate, and the functional properties used for value addition during food product development in the industry. Therefore, application of pretreatment methods particularly chemical treatments could enhance nutritional value, and functional and physical properties of tuber flours.

Effect of Pretreatment and Drying Methods on the Quality of Anchote (Coccinia abyssinica (Lam.)) Flour

Reduction of postharvest losses through improved technique is studied in this work. Pretreatment and drying, in particular, are important methods for using various tuber-based food items to produce intermediate products that increase economic benefit and availability with a longer shelf life in the production and consumption communities. This study was conducted to evaluate the effect of pretreatment and drying methods on the proximate composition and physical and functional properties of flour developed from anchote. The treated anchote flour was prepared using hot distilled water for blanching and potassium metabisulphite solution and drying methods (sun, solar, and oven). The obtained data were statistically analyzed using SAS software at $P<0.05$ . Accordingly, the untreated and sun-dried anchote had greater moisture content (10.34%) than the chemically treated and oven-dried anchote (8.71%). The samples treated with potassium metabisulphite and the solar-drying methods have higher protein content (4.02%) than the blanched and sun-dried samples (3.14%). Samples treated with blanching and solar drying have lower ash content (3.96%) than samples treated with potassium metabisulphite and dried (4.89%). The highest fiber content was recorded for samples treated with blanching and oven-drying methods, with a rating of 4.71%. Sun-dried samples had an increased fat content (1.14%) compared to blanch with all drying methods (0.72%). The untreated and sun-dried flour had lower carbohydrate content (80.95%) than blanched and oven-dried (83.03%). The potassium-metabisulphite-treated and oven-dried samples rated 2.66% with the highest water absorption value. The blanched and oven-dried samples had the lowest oil absorption capacity of 1.71%, a significantly different value from the highest value of 1.98% for the potassium-metabisulphite-treated and solar-dried samples. Oven-dried samples had higher swelling power than solar- and sun-drying methods. The anchote samples treated by blanching methods and dried in the oven had the highest solubility rating of 43.84% and the lowest value of 38.8% for control and sun-dried samples. The sun-dried anchote flour had the highest dispersibility value, which is significantly different from both the oven-dried and solar-dried versions. Along with that, the untreated samples had significantly lower dispersibility values than the potassium-metabisulphite-treated and blanched flour samples. The proximate values of anchote flour were significantly affected by pretreatment and drying methods. Additionally, the main and interactive effect of pretreatment and drying methods influenced the water absorption capacity, oil absorption capacity, swelling power, solubility, and dispersibility significantly. Further research is required to improve flour properties and characterize pasting properties to assess the suitability of the starch for different industrial inputs.

Nutritional, Textural, and Sensory Quality of Aloe Vera Leaf Gel Powder Fortified Plain Cake

Aloe Vera leaves have great potential as an economic supplement with an adequate nutritional profile. The current study aimed to fortify plain (loaf) cakes with Aloe Vera leaf gel (AVG) powder. AVG was freeze-dried to produce Aloe Vera powder (ALP), and four plain (loaf) cakes were prepared with different proportions of ALP (0, 4, 6, and 8%). ALP contained significantly (p < 0.05) more protein (22.23 vs. 12.24), ash (19.83 vs. 0.64), and iron (175 vs. 3.05) than refined wheat flour (RWF). Along with total polyphenols and total flavonoids, ALP demonstrated good antioxidant activity. ALP-cakes and RWF-cakes were also evaluated for their nutritional and functional properties. The addition of 6 and 8% ALP to the formulation increased total polyphenols, total flavonoids, and antioxidant activity in plain (loaf) cakes. Hardness and chewiness increased in ALP-cakes but decreased in RWF-cakes, while cohesiveness and springiness decreased in ALP-cakes. In conclusion, the best formulation was a 4% ALP incorporated cake, and ALP can be supplemented in plain cakes at a rate of up to 8% to improve nutrient value. This is the first study to evaluate the quality characteristics of fortified plain (loaf) cakes using ALP.

Valorization of Goat Cheese Whey through an Integrated Process of Ultrafiltration and Nanofiltration

Goat cheese whey is a co-product that comes from goat cheese manufacture. Due to its high organic load, adequate treatment is necessary before its disposal. Additionally, the recent growing interest in caprine products, attributed to their specific nutritional and nutraceutical characteristics, such as the lower allergenicity of their proteins and higher content of oligosaccharides, compared with bovine products, made the recovery of goat cheese whey a challenge. In this study, an integrated process for the recovery of sweet goat whey components was carried out. It includes filtration, centrifugation and pasteurization, followed by sequential membrane processes, ultrafiltration/dilution, nanofiltration of ultrafiltration permeates in dilution mode and the concentration/dilution of nanofiltration retentates. Ultrafiltration was performed with membranes of 10 and 1 kDa. Membranes of 10 kDa have higher permeate fluxes and, in a single stage of dilution, allowed for better protein retention and higher lactose purity, with a separation factor of 14. The concentration of lactose by nanofiltration/dilution led to the retention of almost all the lactose in retentates and to a final permeate, whose application in cheese dairy plants will allow for the total recovery of whey. The application of this integrated process in small- or medium-sized goat cheese dairies can represent an important contribution to their sustainability.

Systematical characterization of functional and antioxidative properties of heat-induced polymerized whey proteins

Effects of pH (6-8), protein concentration (6-11%, w/v), heating temperature (70-95 °C) and time (5-30 min) on functional and antioxidative properties of heat-induced polymerized whey protein were systematically investigated. All samples were determined for solubility at pH 4.6, emulsion capacity and stability, and antioxidative properties involving 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis(2-ethylbenzothiazoline-6-sulfonate) (ABTS) scavenging abilities. Heating resulted in significant loss in solubility, emulsion capacity and stability for whey protein, p < 0.05. Heating decreased DPPH but enhanced ABTS scavenging ability for whey protein significantly, p < 0.05. Changes caused by pH variation were much stronger than those observed for other factors. Both protein concentration and heating time had negative effects while heating temperature had positive effect on emulsion capacity of whey protein. Data indicates that functional and antioxidative properties of whey protein could be altered by factors including pH, protein concentration, heating temperature and time.

Quality assessment of dried okara as a source of production of gluten-free flour

BACKGROUND

Okara is a by-product of soymilk and of tofu elaboration that is rich in protein, fiber and vegetable oils as a source of gluten-free flour. In order to take advantage of the nutritional characteristics of okara and to be able to determine an appropriate drying methodology, microwave, rotary dryer and freeze-drying were assessed. Furthermore, flour with an enzymatic treatment was characterized as well as its functional, physicochemical, and textural properties.

RESULTS

The results showed that the physiochemical characteristics of the flour were affected by the drying process, reaching adequate water content, and high protein and fiber content. The freeze-drying process produced clearer flours with porous structure and high water absorption capacity, and with a higher protein denaturation. Okara dried by microwave and rotary dryer exhibited a denser structure with similar functional properties and improved textural characteristics such as firmness and consistency. The microwave-produced flour was darker due to the non-enzymatic browning reactions. The enzymatic treatment employed improved the consistency of the flour.

CONCLUSION

It was possible to choose the drying process to be applied according to the feasible use of the flour, intended to preserve the favorable nutritional aspects of the okara flour. Based on the results, it can be affirmed that the physicochemical properties and attributes of okara are influenced by the drying process employed. Okara dried by freeze-drying resulted in a better product because it had a low final moisture content and the highest whiteness index. The flour presented a porous structure with high solubility, which is an indicator of potential applications in foods developments. © 2016 Society of Chemical Industry.

Incorporation of Okara into Gluten-Free Cookies with High Quality and Nutritional Value

Soy products are a source of protein relatively inexpensive and recognized for their high nutritional value and functional properties. Okara is a byproduct from soy milk production. Gluten-free cookies have been developed using okara and commercial manioc flour. Four formulations were developed with different proportions of okara: 50%; 30%; 15%; and 0%. Physicochemical, physical properties, sensory analysis, and nutritional studies were performed. The use of inulin as partial replacement of sugar was evaluated. The incorporation of okara increased protein and fiber content. Furthermore, the hardness of cookies increased while the index of whiteness decreased. From the sensory evaluation, it could be concluded that the cookies presented a great acceptability. The cookies developed in this study have functional characteristics, providing added value to a waste product; furthermore the products were suitable for celiacs with acceptable quality and improved nutrition value.