Comparison of biopreservatives obtained from a starter culture of Pediococcus acidilactici by different techniques

The general objective of this study was to analyse freeze-drying (FD) and spray- drying (SD) and to select the best process to obtain a grapefruit powder of high nutritional, functional and sensorial quality. With this objective in mind, the optimization of each dehydration process was carried out using the response surface methodology. As variables of the processes, in both cases, the concentration of gum arabic (GA) and bamboo fibre (BF), added as carriers, were considered, as well as the feed inlet moisture (Xw) in the case of FD or air inlet temperature (T) in SD. The properties of the obtained products analyzed were the water content, hygroscopicity, porosity, color, bioactive compounds (vitamin C, total carotenoids, total phenols) and antioxidant activity (AOA). In addition, the drying yield and product yield of SD were considered. The obtained results, duly validated, allow to propose for FD, the addition of 4.2g GA and 0.58g BF per 100g of grapefruit pulp and bringing the sample to 90g water/100g feed mixture. In the case of SD, the best product is obtained with T in the equipment is of 120 °C and the addition of 4g AG and 2g BF/100g liquidized grapefruit. The comparison of both products allows us to propose FD as being a better technique than spray-drying. In addition, the powder yield of FD is much higher compared to SD and far fewer by-products are generated. A specific study was carried out to confirm the encapsulating power of the two solutes used. The results obtained confirm the benefit of the joint addition of GA and BF, especially against the spray-drying temperature, offering a greater protection against the degradation of bioactive compounds and AOA, than when solutes are added separately. The characterization of the different bioactive compounds and their correlation with the AOA carried showed that the phenolic compounds contribute significantly to the free radical scavenging activity and the inhibition of the discoloration of s -carotene, while ascorbic acid and ?- tocopherol contribute to an increase in reducing power. In addition, the stability of the optimized powders during storage at 4 and 20 °C and different surrounding relative humidities has been studied. The modeling of the water sorption data together with the variation in the glass transition temperature (Tg) that takes place in line with the water content of the samples permits the determination of the critical values of water content and water activity that ensure the glassy state of the powdered product. In this sense, what is recommended when storing the powders is to maintain the products under refrigeration and with a surrounding relative humidity in the order of 10%. As soon as the grapefruit powder begins the Tg, the degradation of the bioactive compounds begins, with carotenoids being the most sensitive. In less restrictive storage conditions than those mentioned above, in just one month of storage there are already significant losses in the studied compounds, fewer in the FD product than in the SD. In order to detect any…

In our study, oleoresins were explored for their ability to replace the original ground spice and herbs with a standardized taste and aroma, and mask the salt reduction. In order to protect taste and aroma oleoresins from high temperature, and to improve their solubility in food matrices, encapsulation with inulin and maltodextrin was carried out from two mixtures of oleoresins using two drying processes (spray and freeze drying), thus allowing it to be used as an additive to reduce salt for convenience in the food industry. The oleoresins experiment was conducted with two mixtures to apply to meat and fish. Oleoresins were obtained by solvent extraction, and the solvent was removed by evaporation, encapsulated into inulin and maltodextrin microcapsules, and powdered by spray and freeze drying. Physicochemical analyses were carried out using several methods (drying yields, water activity, solubility, hygroscopicity, color, encapsulation efficiency), and characterization of the microcapsules was done by scanning electron microscopy. The total phenolic compounds were quantified using the Folin-Ciocalteau method, and the chemical compounds present in the microcapsules were elucidated by high resolution mass spectrometry. Freeze and spray drying the microcapsules presented good quality products with high yields, high encapsulation efficiency and good solubility. The spray drying process can offer better applications for the food industry due to the more regular shape of the microcapsules. In addition, inulin microcapsules obtained by spray drying showed a more protective effect for flavonoid compounds in fish oleoresins, while maltodextrin microcapsules offered more protection for hydroxycinnamic acids in meat oleoresins. The present study shows an attractive encapsulation system for non-volatile compounds from oleoresins, which results in standardized taste and aroma products that can reduce salt in food systems with different compositions.

Watermelon is a seasonal fruit high in essential ingredients such as lycopene. Due to high water content and water activity, watermelon fruit is susceptible to microbial and enzymatic deterioration. Thus, drying fruit juices into powders has been one of the common methods used to preserve the fruit. A study was conducted to produce watermelon powders using spray dryer and freeze dryer techniques. The major concern is to produce high-quality watermelon fruit powders. Four watermelon extract samples were used on two concentrations of maltodextrin, which were 5% and 13% towards spray drying and freeze-drying technique. The powders were analysed for water content, water activity, colour, and solubility. Results demonstrated that the water activity of watermelon powder using the spray drying technique is less than freeze-drying (0.23-0.27 and 0.44-0.47, respectively). The colour analysis showed that freeze-dried watermelon powder has higher redness (a* value), and yellowness (b* value) than the spray dried powder. The water content of the watermelon powder showed that spray-drying yields lower water content than freeze-drying techniques for both 5% (w/w) and 13% (w/w) of maltodextrin. The solubility of the watermelon powder showed that freeze-drying has a higher solubility time than spray drying. The study found that the spray drying technique is the preferable method to preserve and producing high quality watermelon powder.

The thermal transitions of spray-dried (SD) and freeze-dried (FD) egg whites containing unfreezable water (i.e., lower water contents) and freezable water (i.e., higher water contents) were measured by differential scanning calorimetry (DSC). For the SD and FD samples containing unfreezable water (0.039–0.282 and 0.043–0.206 g water/g sample (w.b.) in SD and FD samples), the denaturation temperatures (Td) of ovotransferrin and ovalbumin were observed in both the SD and FD samples. However, it was difficult to identify the glass transition temperature (Tg) of the egg whites. The Tg was only detected in SD egg whites with low water contents (0.039–0.093 g water/g sample (w.b.)). For the SD and FD samples containing freezable water (0.32–0.72 and 0.31–0.73 g water/g sample (w.b.) in SD and FD samples), the glass transitions were not detected, and only the freezing points (TF) and the end point of freezing (Tm′) were observed. The unfreezable water content and the corresponding characteristic end point of freezing (Tm′)u of the SD samples were both greater than those of the FD samples. The heat denaturation of egg white proteins and different protein solubility (water-binding capacity) may cause the different thermal transitions between SD and FD egg whites. But the Guggenheim-Anderson-de Boer (GAB) monolayer water contents of the SD and FD egg white powders were similar. The results are useful for selecting the optimal process and storage conditions for dried and frozen egg whites.

Generally, Acehnese use asam sunti as a spice in cooking. Asam sunti is made from dried belimbing wuluh (Averrhoa bilimbi Linn), it has a flat shape with brownish colour. To increase the aesthetic value, ease of storage, and maintain its quality, asam sunti is produced in powder form. The quality of asam sunti is determined from several parameters such as water content, ash content and oxalic acid content. The powdered asam sunti was prepared by using Tray and Spray Dryer. The effects of temperature and duration of drying on the quality of asam sunti have been studied. Aesthetically, it is seen that the powdered asam sunti has better appearance than that of the original form. The water, ash and oxalic acid contents in the powdered asam sunti dried using a spray dryer was lower than that of dried by tray dryer. The optimum temperature was obtained at 80 °C. The optimum drying time were 45 minutes and 3 hours for spray and tray dryer, respectively. Water, ash and oxalic acid contents in optimum condition with tray dryer were 49.7%, 26.3% and 10.4%, consecutively. Meanwhile, by using spray dryer, the product has higher quality in terms of water content (4.7%), ash content (14.25%) and oxalic acid level (9.48%).

Effect of spray and freeze drying on physico-chemical, functional, moisture sorption and morphological characteristics of camel milk powder

This study aimed to evaluate the influence of maltodextrin addition on the flow properties of cocoa pulp powder obtained by spray and freeze drying. Cocoa pulp samples received 15% and 30% (m m-1) maltodextrin DE20. Two drying methods were used, spray and freeze drying. Powder morphology was evaluated through scanning electron microscopy (SEM). Wall friction angle, bulk density and tapped density were determined. Carr index (CI), Hausner ratio (HR) and flow index (FI) were used to evaluate powder flow. The particles powders obtained by spray drying showed rounded shapes, whereas the freeze dried powder showed irregular shapes. Increased maltodextrin concentration in the samples altered the powder particle size by spray drying and powder particle surface by freeze drying. The powder by spray drying of the sample with 30% of maltodextrin showed smallest wall friction angles, 13.4 to 14.9. The powder by freeze drying of the samples with 15% and 30% of maltodextrin showed wall friction angles between 14.0 and 20.6. Regarding flow, the powders by spray drying containing 30% of maltodextrin showed the best CI, HR and FI, 24.88, 1.33 and 4.88, respectively, being considered an acceptable flow. According to CI, HR and FI values, samples with 15% of maltodextrin produced powder classified as difficult flow in both methods applied. The higher maltodextrin concentration in cocoa pulp, the lower agglomeration in the powder by spray drying and the smoother particles surfaces in the powder by freeze drying. The addition of maltodextrin to the samples, for both drying methods, improve the powder flow and decrease the powder cohesion.

The use of colorants in products of animal origin is justified by the improvement in the color of foods since this attribute is considered a quality criterion. These additives can be produced using industrial effluents as substrates and appropriate organisms, such as Rubrivivax gelatinosus. Oxycarotenoids represent a class of carotenes responsible for the pigmentation of animals and vegetables. R. gelatinosus grows in fish industry effluent with the resulting production of a bacterial biomass containing oxycarotenoids. The purpose of this study was to compare the use of two drying processes - spray and freeze drying - to obtain powder biomass in terms of the process parameters (yield, productivity, and product recovery) and the product characteristics (color, proximate composition, and oxycarotenoids). No difference was detected in the yield between these techniques, while productivity was higher using spray drying. Higher product recovery and moisture were achieved with freeze drying, while ash was higher with spray drying. The freeze dried biomass was redder, darker and less saturated than the spray dried biomass. No difference in oxycarotenoids was detected between the biomasses. Although it results in lower recovery rate, spray drying was faster and more productive, and it provided the same yield as freeze drying, which makes it the method of choice for obtaining R. gelatinosus biomass.

The use of colorants in products of animal origin is justified by the improvement in the color of foods since this attribute is considered a quality criterion. These additives can be produced using industrial effluents as substrates and appropriate organisms, such as Rubrivivax gelatinosus. Oxycarotenoids represent a class of carotenes responsible for the pigmentation of animals and vegetables. R. gelatinosus grows in fish industry effluent with the resulting production of a bacterial biomass containing oxycarotenoids. The purpose of this study was to compare the use of two drying processes - spray and freeze drying - to obtain powder biomass in terms of the process parameters (yield, productivity, and product recovery) and the product characteristics (color, proximate composition, and oxycarotenoids). No difference was detected in the yield between these techniques, while productivity was higher using spray drying. Higher product recovery and moisture were achieved with freeze drying, while ash was higher with spray drying. The freeze dried biomass was redder, darker and less saturated than the spray dried biomass. No difference in oxycarotenoids was detected between the biomasses. Although it results in lower recovery rate, spray drying was faster and more productive, and it provided the same yield as freeze drying, which makes it the method of choice for obtaining R. gelatinosus biomass.

Microencapsulation of flax oil with zein using spray and freeze drying

Red fruit oil is a potential coloring agent with high carotenoid content. Oil encapsulation could be done to improve its applicability to food products. This study evaluated the effect of different ratios of maltodextrin and whey protein during the encapsulation process of red fruit oil using spray and freeze drying. The powders were analyzed in terms of total carotenoid content, physicochemical properties, and stability. Spray drying resulted in powders with lower moisture content. Freeze drying resulted in powders with high carotenoid content in most samples. All powders showed low hygroscopicity and low crystallinity, but also low flowability. Spray-dried powders were spherical and wrinkled, while freeze-dried powders were irregular and rough. Sample with 1:1 ratio of maltodextrin and whey protein showed generally better properties in both spray and freeze drying. Freeze-dried powder showed better carotenoid stability than spray dried powder throughout the 4 weeks storage period.

Beetroot is a root vegetable with carotenoids, phenols, vitamins, minerals, and water-soluble betalain pigments such as betacyanins (red-violet color) and betaxanthins (yellow-orange color), which have many nutritional and health benefits. Its use in the food industry is mainly as a powdered natural dye. This study aims to investigate the effect of adding pea protein to beetroot juice as an encapsulating agent, and the spray-dried temperature on the physicochemical, structural, and functional properties of the powder. The spray drying was conducted at 125 and 150 °C with 3.5% and 7% pea protein used in the mixtures with the beetroot juice. The water content, bulk density, porosity, hygroscopicity, water solubility, water absorption index, color, and microstructure of the obtained powder were determined. In addition, betacyanin, total phenols, antioxidant capacity, and powder encapsulate efficiency were analyzed. Using pea protein in the spray drying of beetroot juice had shown high yields of spray drying and good characteristics of the powdered product. Beetroot powder with 7% of pea protein was more porous and luminous, and less hygroscopic than beetroot powder with 3.5% of pea protein. However, the use of 7% of pea protein increased the amount of water immobilized by the samples and reduced the soluble solids present in the product compared to beetroot powder with 3.5% of pea protein. The use of 7% of pea protein protected beetroot bioactive compound higher than the use of 3.5%. Higher spray-drying temperature (150 °C) significantly decreased phenols content and antioxidant capacity of the beetroot powders (p < 0.05). Results showed using 7% pea protein mixed with beetroot juice and a 125 °C spray-drying temperature gave the most content of the studied bioactive compounds and antioxidant capacity. Moreover, the proposal gives more stable powders from a functionality viewpoint because it showed the higher encapsulate efficiency.

Background: Whey powder production from whey, a dairy by-product, remains a significant challenge. This study aimed to evaluate how spray drying and freeze drying methods influence the quality of whey powder by comparing their physical, chemical, and functional characteristics. Methods: Six whey samples were collected from a local manufacturer in September 2024 with three processed by spray drying and three by freeze drying. Spray drying was performed at an inlet temperature of 160 °C and freeze drying at -41 to -65 °C under vacuum pressure (0.05 mbar), both with 5% maltodextrin added. The powders were analyzed for physical (color, solubility, hygroscopicity, and wettability), chemical (moisture content, protein content, and titratable acidity), and functional (bulk density, tapped density, Carr’s index, Hausner ratio, foaming capacity, and foaming stability) properties following AOAC and standard methods. Statistical analysis employed one-way ANOVA and Duncan's Multiple Range Test using SPSS (version 22.0, SPSS Inc., Chicago, IL) at a 5% significance level (p<0.05). Results: Spray dried powder had significantly lower moisture (3.26%) and higher titratable acidity than freeze dried powder (p<0.05); nevertheless, there was no apparent difference in the protein content (20-21.01%). Spray dried powder appeared lighter and less greenish in color, whereas freeze dried powder exhibited more yellowish and greenish tones. Solubility (98.76-98.87%) and hygroscopicity (49.06-49.26%) were not significantly different. However, spray dried powder showed lower wettability (154 s). No significant differences were observed in bulk and tapped densities. Flowability was poor in spray dried powder and very poor in freeze dried powder. Freeze dried powder showed significantly higher foaming capacity and stability (p<0.05). Conclusion: Both drying techniques are suitable for large-scale production, depending on their specific uses within the food and pharmaceutical sectors. However, considering factors such as stability, flowability, and economic viability, spray dried powder demonstrated higher efficacy than freeze dried powder.

Background: Tender coconut water contains antioxidants vitamin C, amino acids, L-arginine, polyphenols, selenium, and minerals that prevent oxidative stress, anemia, and inflammation. It also lowers lipid profiles, increases enzyme antioxidant status, and controls lipid peroxidation. Previous investigations have shown that tender coconut water provides health benefits but is difficult to store. This is due to its short shelf life, which can be extended by drying to obtain a dry or powdered form. A special drying method to acquire dry materials and maintain the characteristics of the raw materials is spray or freeze drying. Objective: This study aims to develop tender coconut water into a powder fortified with vitamin E and to differentiate the active compound content of the powder processed by spray and freeze drying. Method: This study used a randomized block design and the sample used was green tender coconut water (Viridis variety) aged about 5-7 months from the Bogor area. The procedures include the purchase of tender coconut water, followed by spray and freeze drying, while the content of active compounds that are beneficial to health was also analyzed. Drying was carried out at the Seafast Center Laboratory of Research and Community Service Institute, Bogor Agricultural Institute (IPB), while the active compound content was analyzed at the Integrated Research and Testing Laboratory, Gadjah Mada University (UGM), Yogyakarta. Result: The active compounds analyzed from powder made from tender coconut water fortified with vitamin E were vitamin C, phenol, L-Arginine, L-Histidine, L-Lycine, L-Phenylalanine, L-Isoleucine, L-Leucine, L-Valine, and minerals consisting of Cu (Copper), Fe (Iron), Mg (Magnesium), Zn (Zinc), Na (Sodium), K (Potassium), and P (Phosphor). Conclusion: There are differences in the content of active compounds in tender coconut water powder fortified with vitamin E between freeze and spray-drying methods.

The different drying methods for preserving fruits may affect fruits' physical and chemical properties, especially dried berries. The expected drying techniques include Spray Drying (SD) and Freeze Drying (FD). The physical characteristics, such as color, taste/odor, and thermal properties, have changed during the process. The higher temperatures in spray drying may affect the phytochemical compounds that will change the final nutritional value. The juice taste and color of berries powders that FD produces are better than SD. However, the morphology of powder that resulted from SD is better. Also, the losses of phenolic compound and anthocyanin content of dried berries produced from SD are much lower than FD. Therefore, the choices of higher quality dried berries can be produced by FD that are suitable to preserve the phytochemical compounds that have health benefits.  Â