High-pressure Processing Method Research Articles

Edible oil to powder technologies: Concepts and advances

There is a recent surge in demand for nutritious food from the consumer end. Functional foods are gaining much popularity. With the commercialization of omega-3 fatty acids and their many nutritional advantages, edible powders and smoothies loaded with PUFA are available on the market. Edible oil powders are one such commodity that is consumed for their several nutraceutical properties such as, reducing cardiovascular risk, aiding in weight reduction, providing antioxidant properties, etc. Edible oil is first stabilized into stable emulsions which are then processed to obtain powders. The process of oil-in-water emulsion stabilization is carried out using ultrasonication, homogenization, microfluidization, complex coacervation, and oil structuring mechanisms. The stable emulsions are then microencapsulated using various wall material combinations and ratios to form stable edible oil powders. The wall material protects the active molecules from the ambient environment, high temperature, and high-pressure processing methods. These powders are added to coffee, smoothies, cookies, yogurt, cake mix, and soup powder to impart functional properties to foods. The major challenge in the production of oil powder is the formation of stable emulsion with proper wall-to-core ratio and binding of the wall with core materials to form stable powder with an increased shelf life. This article provides a detailed review of various emulsion stabilization techniques and processing methods to form edible oil powders.

A novel method for the microencapsulation of curcumin by high-pressure processing for enhancing the stability and preservation

Curcumin is used for the development of new pharmaceutical and food products, but its application is generally hindered by the poor solubility of curcumin and thermal instability during storage and processing. In this study, the liposomes of curcumin (cur-liposomes) were prepared by a novel combination of ethanol injection and high-pressure processing (HPP) to enhance the stability and preservation of curcumin. The pasteurization, mean particle size, size distribution, and encapsulation efficiency of cur-liposomes and the kinetics of their thermal degradation were also investigated in this research. From the results, the kinetic rate constants of curcumin in samples of free curcumin and cur-liposome at 25 °C were found to be 1.6 × 10−3 and 0.8 × 10−3 min−1, respectively. The phospholipid bilayer structure could protect curcumin. The results propose that the HPP method for liposome preparation is superior to the probe-sonication method in terms of stability, encapsulation efficiency, and homogeneity. Furthermore, the preparation of cur-liposomes by HPP with a hydrostatic pressure of 200 MPa could maintain the optimal particle size (206.4 nm) and polydispersity index (0.19). Conclusively, the combination of ethanol injection and HPP can not only successfully inactivate the microorganisms during liposome preparation for microencapsulation of bioactive compounds but also effectively preventthe thermal degradation of heat-sensitive substances in non-thermal processing for practical applications.

A New Approach for the Microencapsulation of Clitoria Ternatea Petal Extracts by a High-Pressure Processing Method.

Toxic organic solvent residues and the active substances of thermal degradation (such as anthocyanin and polyphenols) are always a concern with the liposomes produced by traditional techniques. The present study focuses on a new approach for the microencapsulation of Clitoria ternatea petal (CTP) extracts, which contain anthocyanins, by high-pressure processing (HPP) at room temperature. Thus, a series of CTP liposomes were prepared and their physicochemical properties were analyzed by laser granulometry and by scanning electron microscopy (SEM). The results revealed that the average particle size of the liposomes after HPP treatment increased gradually from 300 MPa to 600 MPa, possibly due to the aggregation of liposomes and damage to the phospholipid bilayers. For the preparation of liposomes by the HPP method at 300 MPa, the mean particle size, polydispersity index (PDI), and encapsulation efficiency were 240.7 nm, 0.37, and 77.8%, respectively. The HPP method provided a number of advantages over conventional methods (magnet stirring and ultrasonication) as it could allow liposome preparation with higher encapsulation efficiency, smaller size, and narrower, more reproducible particle size distribution. Conclusively, microencapsulation in the liposomes was successfully achieved with the fast-adiabatic expansion of HPP.

Donor Human Milk for Preterm Infants: A Cost-Consequence Analysis of Alternative Preservation Methods

ObjectivesTo perform cost-consequence and cost-effectiveness analyses of 2 methods of donor human milk (DHM) preservation—Holder pasteurization (HoP) and high-pressure processing (HPP)—in human milk banks in Poland. MethodsWe used the results of the LACTOTECHnology as an answer to special nutritional requirements of preterm infants (LACTOTECH) preclinical study on the impact of different preservation methods on the content of bioactive milk components. The cost analysis was performed from the hospital perspective. To estimate the Diagnosis-Related Group (DRG) tariff for enteral feeding with DHM preserved by HPP, the pricing process used by the Polish health technology assessment agency (Agencja Oceny Technologii Medycznych i Taryfikacji) was followed. One-way deterministic and probabilistic sensitivity analyses on costs and human milk component parameters were undertaken. ResultsHPP maintains an average of 55% more potentially beneficial DHM components than HoP, but is more expensive (€35 750 vs €5066). The DRG tariff relating to milk from human milk banks preserved by the HPP method should be about €54 (130%) higher than with HoP. The cost-effectiveness ratio ranged from €0.84 to €10.27 per 1% gain in the active compound content in a daily portion of DHM. Sensitivity analysis showed that the cost of an HPP device had the most significant impact on pascalization expenses. ConclusionsHPP is a potentially more beneficial method of DHM preservation than HoP, but it is also about 7 times more expensive. Because of high pascalization costs, the cost-effectiveness analysis based on clinically significant endpoints will play an important role in decision making regarding the implementation of HPP into clinical practice of human milk banking.

Comparison between thermal pasteurization and high pressure processing of bovine skim milk in relation to denaturation and immunogenicity of native milk proteins

Abstract High pressure processing (HPP), conducted at 400, 500 or 600 MPa for 15 min at 30 °C, of raw skim milk was studied in comparison to high-temperature short-time (HTST) pasteurization (72 °C for 15 s), considering protein denaturation and immunogenicity. HTST pasteurization least impacted denaturation of native proteins leading to mostly unchanged milk immunogenicity. HPP resulted in denaturation of whey proteins, mostly β-lactoglobulin (BLG) and immunoglobulin G (IgG), and disturbed structure of the casein micelle. HPP at 600 MPa caused protein aggregation, involving mainly BLG and κ-casein, through thiol disulphide interactions. α-Lactalbumin (ALA) was least denatured. The balance between expression of T helper (Th)1 and Th2 type cytokines, which is believed to regulate adverse immune response, was initially shifted toward Th1 with increasing high pressure, then the immunogenic capacity of milk proteins diminished at 600 MPa. This could be related to exposure of T cell-specific linear epitopes followed by unfolding of protein structure firstly and masking of them by protein aggregation subsequently with increasing high pressure. Industrial relevance HPP of raw milk has been well studied as an alternative process for conventional thermal pasteurization, based on inactivation of microorganisms and extension of shelf life. However, HPP can denature native milk proteins leading to altered immunogenicity. Three recommended HPP conditions and a commercial HPP method were assessed in comparison to HTST pasteurization considering impact on denaturation of milk proteins and milk immunogenicity. Scientific findings of the current study would guide the industry to identify HPP conditions that not only achieve the required level of microbial inactivation and shelf life, but also to establish desired levels of native properties of milk and milk immunogenicity.

Comparison Between High-Pressure Processing and Chemical Extraction: Astaxanthin Yield From Six Species of Shrimp Carapace

ABSTRACTAstaxanthin is one of the main carotenoid pigments. It has beneficial effects on the immune system of the human body due to its powerful antioxidant properties. The application of this bioactive compound can be found to be significant in the food, pharmaceutical, and cosmetics industries. The aim of this research was to investigate astaxanthin yield from six species of Malaysian shrimp carapace. Six types of shrimp species—Parapenaeopsis sculptili, Metapenaeus lysianassa, Macrobrachium rosenbergii, Metapenaeopsis hardwickii, Penaeus merguiensis, and Penaeus monodon—were used to investigate total carotenoid content and astaxanthin yield. The investigation was carried out using chemical extraction and high-pressure processing (HPP) methods at 210 MPa, for a period of 10 min with a solvent mixture of acetone and methanol (7:3, v/v). HPP was proven to have a significant impact in increasing the total carotenoid content and astaxanthin yield. The highest total carotenoid content and astaxanthin yield is shown to be contained in the Penaeus monodon species. Total carotenoid was increased from 46.95 µg/ml using chemical extraction to 68.26 µg/ml using HPP; yield of astaxanthin was increased from 29.44 µg/gdw using chemical extraction to 59.9744 µg/gdw using HPP. Therefore, comparison between the HPP and chemical extraction methods showed that HPP is more advantageous with higher astaxanthin yield, higher quality, and shorter extraction time.

Engineering Process Characterization of High-Pressure Homogenization—from Laboratory to Industrial Scale

Fluid foods are a rapidly growing segment serving the needs of consumers’ healthy life style. Though high-pressure pasteurized beverages have been recently commercialized, the batch nature of the technology has been a hurdle for wider adaptation of the technology for high-throughput commodity-oriented beverage products. Further development of continuous flow through high-pressure processing methods is desired. High-pressure homogenization (HPH) consists of forcing a pressurized fluid to flow through a minute gap, which not only homogenizes the fluid but also increases the fluid’s temperature. HPH offers the possibility of combining homogenization and preservation into a single unit operation. By manipulating initial temperature and applied pressure, HPH treatment can be used to pasteurize or sterilize the product. This work critically examines the efforts in understanding fundamental process engineering aspects of HPH, including pressure-thermal process characterization, valve design (gap size and pressure relation), flow pattern, temperature history, and residence time distribution. This review will also highlight the HPH impact on food quality and bioactive compound retention. Quality aspects examined include particle size distribution and microbial and enzyme inactivation. The insight gained by this review will assist readers to gain a better appreciation of the HPH process design and system scale-up.

Effect of High-Pressure Processing on the Microbial Quality throughout the Shelf Life of Vacuum-Packed Sliced Ham and Frankfurters

Microbial spoilage is one of the most important factors threatening the shelf life of meat products. High-pressure processing (HPP) is growing out of its infancy with an increasing number of commercial applications. The aim of this study was to evaluate the efficiency of HPP on the microbial quality of commercial ham and frankfurters over their shelf life period. Commercially manufactured ham and frankfurters were processed with HPP at 600 MPa for 3 min and were then stored in parallel with nontreated samples (control) at 4C for a period of 7 weeks. All samples were weekly analyzed for the following parameters: total aerobic count (TAC), coliforms, Escherichia coli, staphylococci, yeasts and moulds, Salmonella spp., and Listeria spp. At the end of the tested shelf life period, a significant difference (P < 0.005) was observed on the TAC between HPP-treated and nontreated samples for both products tested, demonstrating the efficiency of the HPP method. Practical Applications This study shows that the HPP treatment at 600 MPa for 3 min is effective at increasing significantly the shelf life of the two products tested. Sliced ham and frankfurters are among the most popular meat products consumed and the majority of the producers apply vacuum packaging to these products. The meat industry is seeking ways to increase the shelf life of these products and it was shown here that this can be achieved by the application of modern commercial HPP systems.

Phytochemical Stability and Color Retention of Copigmented and Processed Muscadine Grape Juice

Muscadine (Vitis rotundifolia) grape juice was assessed for color and phytochemical stability as influenced by anthocyanin copigmentation with a water-soluble rosemary extract, fortification with ascorbic acid, and processing by heat or high hydrostatic pressure (HHP). The roles of polyphenolic cofactors in the presence and in the absence of ascorbic acid were assessed as a means to improve the overall processing stability of the juice. Addition of rosemary extract from 0 to 0.4% (v/v) readily formed copigment complexes with anthocyanins and resulted in concentration-dependent hyperchromic shifts from 10 to 27% that corresponded to increased antioxidant activity. The presence of ascorbic acid was generally detrimental to juice quality, especially in the presence of rosemary extract, and resulted in overall anthocyanin, ascorbic acid, and antioxidant activity losses. Although thermal and high-pressure processing methods were detrimental to juice quality, HHP resulted in greater losses after processing, likely due to action from residual oxidase enzymes. Although physicochemical attributes were enhanced by copigmentation with rosemary extract, methods to inactivate residual enzymes should be addressed prior to copigmentation to prevent degradation of anthocyanins in the presence of ascorbic acid.