Stability of avocado paste carotenoids as affected by high hydrostatic pressure processing and storage

Effect of Novel Processing Techniques on the Carotenoid Release during the Production of Red Guava Juice

Red guava, distinguished by its elevated lycopene content, emerges as a promising natural source of carotenoids. This study systematically evaluates the impact of diverse processing techniques on the efficient release of carotenoids. The primary objective is to facilitate the transfer of carotenoids into the juice fraction, yielding carotenoid-enriched juice seamlessly integrable into aqueous-based food matrices. The untreated guava puree exhibited a modest release of carotenoids, with only 66.26% of β-carotene and 57.08% of lycopene reaching the juice. Contrastly, both high-pressure homogenization (HPH) at 25 MPa and enzyme (EM) treatment significantly enhanced carotenoid release efficiency (p < 0.05), while high hydrostatic pressure (HHP) at 400 MPa and pulsed electric field (PEF) of 4 kV/cm did not (p > 0.05). Notably, HPH demonstrated the most substantial release effect, with β-carotene and lycopene reaching 90.78% and 73.85%, respectively. However, the stability of EM-treated samples was relatively poor, evident in a zeta-potential value of -6.51 mV observed in the juice. Correlation analysis highlighted the interactions between pectin and carotenoids likely a key factor influencing the stable dissolution or dispersion of carotenoids in the aqueous phase. The findings underscore HPH as a potent tool for obtaining carotenoid-enriched guava juice, positioning it as a desirable ingredient for clean-label foods.

Development of gelatin/agarose active coatings functionalized with Ocimum gratissimum L. essential oil for enhancing storability of 'Booth 7' avocado

Novel active coating from gelatin/agarose (GA) functionalized with Ocimum gratissimum L. essential oil (OGO) had been developed as a medium to evaluate their properties before being applied for avocado preservation. The resultant coating films showed enhanced mechanical, water-barrier, bactericidal, antioxidant, and UV-shielding properties by adding OGO. The best tensile strength (2.91 MPa) and flexibility (45.82 %) was found in the GA film containing 5 % (w/w) of OGO (GA-OGO-5). Furthermore, this coating formulation presented moderate antibacterial activities against Listeria, Pseudomonas, Salmonella, and Escherichia. The GA-OGO-5 coating film also divulged the highest hydrophobicity and adequate antioxidant function (30.75 μg/mL) and thus, was chosen to coat on 'Booth 7' avocados by dipping method. The GA-OGO-5 coating layers were to be efficient to decline the respiration rate of avocado during 6-day storage at 25 °C and 64 %RH. Peel color, weight loss (5.22 %), total soluble solids (8.14 %), and solution pH (6.79) at the end of storage also indicated that the GA-OGO-5 coating presented the best effectiveness for enhancing the storability of avocado as compared to uncoated and GA-treated fruit. Therefore, the GA-OGO coating has been considered as an alternative post-harvest technique to enhance the avocado storability and could be further commercialized for industry application.

Identification and quantification of fatty acids and lipid-soluble phytochemicals using GC-MS, HPLC-MS, and FTIR and their association with quality parameters during avocado ripening

Consumer demand for the avocado fruit has increased considerably, but accelerated fruit ripening, lack of fruit ripening uniformity, and lack of proper quality characteristics and indices generate considerable problems during fruit handling and trade. Physicochemical parameters are used to determine avocado fruit ripening. These parameters together with lipid-soluble phytochemicals (LSP) and fatty acids (FAs) highlight the health and economic importance of this fruit. Analysis of LSP and FAs in avocado fruit has been reported, but combining the use of analytical techniques such as Fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC-MS), and high-pressure liquid chromatography coupled to mass spectrometry (HPLC-MS) to determine qualitative and quantitative changes during fruit ripening, and their association with physicochemical parameters, has not been conducted. Physicochemical parameters (fruit firmness, color, oil and dry matter contents) were determined, and the changes of FAs and LSP (carotenoids, chlorophylls, and tocopherols) during "Hass" avocado ripening, based on dry matter (DM) content, were analyzed using FTIR, GC-MS, and HPLC-MS. The association between them was also determined using principal component analysis. Fruit with 19% and 25% DM exhibited high LSP and FAs levels. Carotenoids, chlorophylls, and tocopherols were associated with firmness, color, and DM of 19% and 22%, while FAs were associated with fruit weight and DM of 25%. PRACTICAL APPLICATION: There is a major global increase in avocado cultivation and consumer demand. However, a major problem facing the handling and trade of avocado fruit is related to lack of fruit ripening uniformity and quality characteristics and indices. Therefore, a proper association between simple measures of fruit physicochemical properties and bioactive components can establish an excellent, simple, and practical index that can eventually be used for quality evaluation by the industry and the consumers.

High pressure processing improves the texture quality of fermented minced pepper by maintaining pectin characteristics during storage

Texture quality affects the sensory and market acceptance of fermentation minced pepper (FMP), but it will deteriorate during storage. Thus, high pressure processing (HPP) and thermal pasteurization (TP) were used to improve the texture quality of FMP during storage. The results showed that variations in texture quality and pectin characteristics under HPP and TP treatments were similar during storage. The hardness, cell wall material (CWM) and sodium carbonate-soluble pectin (SSP) content, water-soluble pectin (WSP) molecular weight (M_w ) decreased, while WSP content and sodium chelate-soluble pectin (CSP) M_w increased after storage. HPP-treated FMP showed higher hardness (66.64-85.95 N) than that in TP-treated one (57.23-62.72 N) during storage. Rhamnose (Rha), arabinose, mannose, and glucose were the crucial compositions in three pectins, and their total molar ratios, respectively, reached 89.19% and 87.97% after HPP and TP treatment. However, the molar ratio of most monosaccharide in three pectins decreased after storage. Atomic force microscope images indicated the short chains and branch structures increased but aggregates decreased in most pectin components during storage. Pearson correlation analysis demonstrated FMP hardness was extremely (p < 0.01) positively correlated with CWM and SSP content, and extremely (p < 0.01) negatively correlated with WSP content. Compared to TP treatment, HPP presented higher hardness, SSP content and M_w , Rha content, CSP M_w , and lower WSP content during storage. Hence, HPP was an effective method to improve the texture quality of FMP by maintaining pectin characteristics during storage. PRACTICAL APPLICATION: Softening is one of the main factors affecting market value and consumer preferences for FMP, and it is closely related to the modification and depolymerization of pectin. Changes of texture quality and pectin properties in HPP- and TP-treated FMP during storage were assessed, including hardness, the content, monosaccharide compositions, M_w distribution, and nanostructure of WSP, SSP, and CSP. Compared to TP treatment, HPP could effectively improve the texture quality of FMP by inhibiting pectin degradation during storage. All the findings presented in this study would help to provide new insights into regulating the texture quality of FMP.

Effect of High Hydrostatic Pressure on the Extractability and Bioaccessibility of Carotenoids and Their Esters from Papaya (Carica papaya L.) and Its Impact on Tissue Microstructure

High hydrostatic pressure (HHP) is a non-thermal technology widely used in the industry to extend food shelf-life and it has been proven to enhance the extractability of secondary metabolites, such as carotenoids, in plant foods. In this study, fresh-cut papaya pulp of varieties (Sweet Mary, Alicia and Eksotika) from the Canary Islands (Spain) were submitted to the HHP process (pressure: 100, 350 and 600 MPa; time: come-up time (CUT) and 5 min) to evaluate, for the first time, individual carotenoid and carotenoid ester extractability and to assess their bioaccessibility using an in vitro simulated gastrointestinal digestion assay, following the standardized INFOGEST^® methodology. In addition, changes in papaya pulp microstructure after HHP treatments and during the different phases of the in vitro digestion were evaluated with optical light microscopy. HPLC-DAD (LC-MS/MS (APCI+)) analyses revealed that HHP treatments increased the carotenoid content, obtaining the highest extractability in pulp of the Sweet Mary papaya variety treated at 350 MPa during 5 min (4469 ± 124 μg/100 g fresh weight) which was an increase of 269% in respect to the HHP-untreated control sample. The highest carotenoid extraction value within each papaya variety among all HHP treatments was observed for (all-E)-lycopene, in a range of 98–1302 μg/100 g fresh weight (23–344%). Light micrographs of HHP-treated pulps showed many microstructural changes associated to carotenoid release related to the observed increase in their content. Carotenoids and carotenoid esters of papaya pulp submitted to in vitro digestion showed great stability; however, their bioaccessibility was very low due to the low content of fatty acids in papaya pulp necessary for the micellarization process. Further studies will be required to improve papaya carotenoid and carotenoid ester bioaccessibility.

Effect of nonthermal treatments on selected natural food pigments and color changes in plant material

In recent years, traditional high-temperature food processing is continuously being replaced by nonthermal processes. Nonthermal processes have a positive effect on food quality, including color and maintaining natural food pigments. Thus, this article describes the influence of nonthermal, new, and traditional treatments on natural food pigments and color changes in plant materials. Characteristics of natural pigments, such as anthocyanins, betalains, carotenoids, chlorophylls, and so forth available in the plant tissue, are shortly presented. Also, the characteristics and mechanism of nonthermal processes such as pulsed electric field, ultrasound, high hydrostatic pressure, pulsed light, cold plasma, supercritical fluid extraction, and lactic acid fermentation are described. Furthermore, the disadvantages of these processes are mentioned. Each treatment is evaluated in terms of its effects on all types of natural food pigments, and the possible applications are discussed. Analysis of the latest literature showed that the use of nonthermal technologies resulted in better preservation of pigments contained in the plant tissue and improved yield of extraction. However, it is important to select the appropriate processing parameters and to optimize this process in relation to a specific type of raw material.

High Hydrostatic Pressure Processing of Whole Carrots: Effect of Static and Multi-Pulsed Mild Intensity Hydrostatic Pressure Treatments on Bioactive Compounds

In this study, the effects of static and multi-pulsed mild-intensity high hydrostatic pressure (HHP) treatments (60 or 100 MPa, ~23 °C) on the extractability and accumulation of phenolics and carotenoids in whole carrots were evaluated. HHP treatments were applied for the time needed to reach the desired pressure (come-up-time, CUT) either as a single pulse or multi-pulse (2P, 3P, and 4P). Likewise, a single sustained treatment (5 min) applied at 60 or 100 MPa was evaluated. Individual carotenoids, free and bound phenolics were quantified after HHP treatment and subsequent storage (48 h, 15 °C). As an immediate HHP response, phenolic extractability increased by 66.65% and 80.77% in carrots treated with 3P 100 MPa and 4P 60 MPa, respectively. After storage, CUT 60 MPa treatment accumulated free (163.05%) and bound (36.95%) phenolics. Regarding carotenoids, total xanthophylls increased by 27.16% after CUT 60 MPa treatment, whereas no changes were observed after storage. Results indicate that HHP processing of whole carrots at mild conditions is a feasible innovative tool to enhance the nutraceutical properties of whole carrots by increasing their free and bound phenolic content while maintaining carotenoid levels. HHP treated carrots can be used as a new functional food or as raw material for the production of food and beverages with enhanced levels of nutraceuticals.

Insights into Drivers of Liking for Avocado Pulp (Persea americana): Integration of Descriptive Variables and Predictive Modeling

Trends in new food products focus on low-carbohydrate ingredients rich in healthy fats, proteins, and micronutrients; thus, avocado has gained worldwide attention. This study aimed to use predictive modeling to identify the potential sensory drivers of liking for avocado pulp by evaluating acceptability scores and sensory descriptive profiles of two commercial and five non-commercial cultivars. Macronutrient composition, instrumental texture, and color were also characterized. Trained panelists performed a descriptive profile of nineteen sensory attributes. Affective data from frequent avocado adult consumers (n = 116) were collected for predictive modeling of an external preference map (R² = 0.98), which provided insight into sensory descriptors that drove preference for particular avocado pulps. The descriptive map explained 67.6% of the variance in sensory profiles. Most accepted pulps were from Hass and Colin V-33; the latter had sweet and green flavor notes. Descriptive flavor attributes related to liking were global impact, oily, and creamy. Sensory drivers of texture liking included creamy/oily, lipid residue, firmness, and cohesiveness. Instrumental stickiness was disliked and inversely correlated to dry-matter and lipids (r = -0.87 and -0.79, respectively). Color differences (∆E_ab*) also contributed to dislike. Sensory-guided selection of avocado fruits and ingredients can develop products with high acceptability in breeding and industrialization strategies.

Comparison of the carotenoid profiles of commonly consumed smear-ripened cheeses

The objective of this study was to identify the carotenoids imparting the orange colour to the rind, and pale yellow color to the core, of selected smear-ripened cheeses. The cheeses investigated were Charloe, Ashbrook, Taleggio, and Limburger, and were sourced from artisanal markets. Samples of the rind and core were extracted using non-polar solvents, followed by saponification to hydrolyze triglycerides to remove fatty acids, and to release carotenoid esters. Extracts were tested using ultra-high pressure liquid chromatograph-diode array detector-high resolution mass spectrometry (UHPLC-DAD-MS and -MS/MS), and identities of α- and β-carotene, lycopene, and β-cryptoxanthin confirmed with authentic standards. β-Carotene was the predominant species in both the rind and core, absorbing ~70% of the signal at 450 nm in all cheese extracts tested, as well as minor quantities of β-cryptoxanthin and α-carotene. Carotenoids unique to the rind included lycopene as well as the rare bacterial carotenoids previously identified in bacterial isolates of cheeses (i.e. decaprenoxanthin, sarcinaxanthin, and echinenone). This is the first detailed characterisation of carotenoids extracted directly from smear-ripened cheeses, and reveals that smear-ripened cheese can contribute both provitamin A carotenoids as well as C50 carotenoids to the human diet.

Phenolic Compounds in Mesoamerican Fruits-Characterization, Health Potential and Processing with Innovative Technologies

Diets rich in phenolic compounds have been associated to reducing the risk of metabolic syndrome and its derived disorders. Fruits are healthy components of the human diet because of their vitamin, mineral, fiber and phenolic profile. However, they have a short shelf-life which is limited by microbiological growth and enzymatic activity. Innovative preservation methods such as high hydrostatic pressure, pulsed electric fields, ultrasound, microwave, cold plasma and ultraviolet light have become popular for the processing of fruits because they can preserve nutritional quality. In this review, the phenolic profile and health potential of 38 Mesoamerican fruits were assessed. Phenolic compounds were classified based on their contribution to the diet as flavonoids, phenolic acids, tannin, lignins and stilbenoids. Due to this composition, fruits showed a wide range of bioactivities which included anti-inflammatory, anti-diabetic, anti-hypertensive and anti-obesity activities, among others. Phenolic content in fruits submitted to innovative food processing technologies depended on parameters such as enzymatic activity, antioxidant capacity, microstructure integrity and cell viability. Innovative technologies could increase phenolic content while assuring microbiological safety by (i) promoting the release of bound phenolic compounds during processing and (ii) inducing the synthesis of phenolic compounds by activation of phenylpropanoid pathway during storage.

Effects of high pressure processing (HPP) on microorganisms and the quality of mango smoothies during storage

The objective of this study is to investigate the effects of high pressure processing (HPP) on the quality of mango smoothies and the inactivation of microorganisms therein, with heat treatments used as the control. Comparative analysis was conducted on the microbiological changes in the mango smoothies subjected to HPP at 400–600 MPa for 0–15 min. The total plate count (TPC) and the yeast and mold (YM) counts were found to be significantly inactivated through increases in the pressure and treatment time (p < 0.05). Conditions of 90 °C/20 min (HT), 500 MPa/8 min (HPP-500) and 600 MPa/5 min (HPP-600) were, thus, selected as the subsequent treatment for a storage study at 4 °C for 15 days, since these conditions had similar inactivation effects on TPC and YM. After 15 days of storage, the TPC was found to have increased by 3.87, 3.54 and 3.36 log₁₀ cycles in the mango smoothies treated by HT, HPP-500 and HPP-600, respectively, while the YM counts remained at less than 1 log₁₀ cycle in all samples. During storage, compared to the HT and HPP-600 samples, both the color and viscosity at 100 s⁻¹ of samples treated by HPP-500 were found to be better maintained. Carotene content was better retained in storage after the HPP process than after the HT process. However, the different treatments had no effect on the pH nor on the total soluble solids (TSS) in the samples. The study ascertained that HPP-500 is able to ensure both the microbial safety and the quality of mango smoothies more effectively than HT and HPP-600.

The objective of this study is to investigate the effects of high pressure processing (HPP) on the quality of mango smoothies and the inactivation of microorganisms therein, with heat treatments used as the control.

Valorization of byproducts from tropical fruits: Extraction methodologies, applications, environmental, and economic assessment: A review (Part 1: General overview of the byproducts, traditional biorefinery practices, and possible applications)

Tropical fruits represent one of the most important crops in the world. The continuously growing global market for the main tropical fruits is currently estimated at 84 million tons, of which approximately half is lost or wasted throughout the whole processing chain. Developing novel processes for the conversion of these byproducts into value-added products could provide a viable way to manage this waste problem, aiming at the same time to create a sustainable economic growth within a bio-economy perspective. Given the ever-increasing concern about sustainability, complete valorization through a bio-refinery approach, that is, zero waste concept, as well as the use of green techniques is therefore of utmost importance. This paper aims to report the status on the valorization of tropical fruit byproducts within a bio-refinery frame, via the application of traditional methodologies, and with specific attention to the extraction of phenolics and carotenoids as bioactive compounds. The different types of byproducts, and their content of bioactives is reviewed, with a special emphasis on the lesser-known tropical fruits. Moreover, the bioactivity of the different types of extracts and their possible application as a resource for different sectors (food, pharmaceutical, and environmental sciences) is discussed. Consequently, this review presents the concepts of tropical fruit biorefineries, and the potential applications of the isolated fractions.

Simultaneous LC/MS Analysis of Carotenoids and Fat-Soluble Vitamins in Costa Rican Avocados (Persea americana Mill.)

Avocado (a fruit that represents a billion-dollar industry) has become a relevant crop in global trade. The benefits of eating avocados have also been thoroughly described as they contain important nutrients needed to ensure biological functions. For example, avocados contain considerable amounts of vitamins and other phytonutrients, such as carotenoids (e.g., β-carotene), which are fat-soluble. Hence, there is a need to assess accurately these types of compounds. Herein we describe a method that chromatographically separates commercial standard solutions containing both fat-soluble vitamins (vitamin A acetate and palmitate, Vitamin D₂ and D₃, vitamin K₁, α-, δ-, and γ-vitamin E isomers) and carotenoids (β-cryptoxanthin, zeaxanthin, lutein, β-carotene, and lycopene) effectively (i.e., analytical recoveries ranging from 80.43% to 117.02%, for vitamins, and from 43.80% to 108.63%). We optimized saponification conditions and settled at 80 °C using 1 mmol KOH L⁻¹ ethanol during 1 h. We used a non-aqueous gradient that included methanol and methyl tert-butyl ether (starting at an 80:20 ratio) and a C₃₀ chromatographic column to achieve analyte separation (in less than 40 min) and applied this method to avocado, a fruit that characteristically contains both types of compounds. We obtained a method with good linearity at the mid to low range of the mg L⁻¹ (determination coefficients 0.9006–0.9964). To determine both types of compounds in avocado, we developed and validated for the simultaneous analysis of carotenoids and fat-soluble vitamins based on liquid chromatography and single quadrupole mass detection (LC/MS). From actual avocado samples, we found relevant concentrations for cholecalciferol (ranging from 103.5 to 119.5), δ-tocopherol (ranging from 6.16 to 42.48), and lutein (ranging from 6.41 to 15.13 mg/100 g dry weight basis). Simmonds cultivar demonstrated the higher values for all analytes (ranging from 0.03 (zeaxanthin) to 119.5 (cholecalciferol) mg/100 g dry weight basis).

Fatty Acid Profile, Total Carotenoids, and Free Radical-Scavenging from the Lipophilic Fractions of 12 Native Mexican Avocado Accessions

Mexico is the world's largest producer, exporter, and consumer of avocados. "Hass" avocado is the most commercialized cultivar, while the native Mexican avocado varieties have been displaced. Thus, studies regarding their chemical and nutraceutical characterization are scarce. We studied the total lipid content, fatty acid profile, carotenoid content, and free radical-scavenging activity of the fruit pulp from 12 accessions of the native Mexican avocado (Persea americana var. drymifolia). The results show that the chemical and nutraceutical characteristics depend on the accession type. The total lipid content ranged from 13.22 to 23.41%. The major saturated fatty acid in all the avocado accessions was palmitic acid (15.54-22.68%). Monounsaturated fatty acids, like oleic (56.58-74.19%), linoleic (5.62-16.85%) and linolenic (0.63-2.85%) acids were the most abundant unsaturated fatty acids in all the native Mexican avocado accessions. The total carotenoid content (1.57 to 7.83 mg eq. of β-carotene 100 g-¹ fresh weight) and the free radical-scavenging activity (7.58-88.62 mMol trolox equivalent 100 g^-1 fresh weight) also varied significantly (p < 0.05) among accessions. Native Mexican avocados have a great nutraceutical potential due to their high content of omega-9, omega-6, and omega-3 fatty acids and carotenoids. These compounds have been reported to display antioxidant activities and protect against cardiovascular diseases.

Bioactive potential of fruit and vegetable wastes

Fruits and vegetables are essential for human nutrition, delivering a substantial proportion of vitamins, minerals, and fibers in our daily diet. Unfortunately, half the fruits and vegetables produced worldwide end up as wastes, generating environmental issues caused mainly by microbial degradation. Most wastes are generated by industrial processing, the so-called by-products. These by-products still contain many bioactive compounds post-processing, such as macronutrients (proteins and carbohydrates) and phytochemicals (polyphenols and carotenoids). Recently, the recovery of these bioactive compounds from industry by-products has received significant attention, mainly due to their possible health benefits for humans. This chapter focuses on the bioactive potential of fruit and vegetable by-products with possible applications in the food industry (functional foods) and in the health sector (nutraceuticals).

Recent Advances in Food Processing Using High Hydrostatic Pressure Technology

High hydrostatic pressure is an emerging non-thermal technology that can achieve the same standards of food safety as those of heat pasteurization and meet consumer requirements for fresher tasting, minimally processed foods. Applying high-pressure processing can inactivate pathogenic and spoilage microorganisms and enzymes, as well as modify structures with little or no effects on the nutritional and sensory quality of foods. The U.S. Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA) have approved the use of high-pressure processing (HPP), which is a reliable technological alternative to conventional heat pasteurization in food-processing procedures. This paper presents the current applications of HPP in processing fruits, vegetables, meats, seafood, dairy, and egg products; such applications include the combination of pressure and biopreservation to generate specific characteristics in certain products. In addition, this paper describes recent findings on the microbiological, chemical, and molecular aspects of HPP technology used in commercial and research applications.

High hydrostatic pressure as a method to preserve fresh-cut Hachiya persimmons: A structural approach

The “Hachiya” persimmon is the most common astringent cultivar grown in California and it is rich in tannins and carotenoids. Changes in the microstructure and some physicochemical properties during high hydrostatic pressure processing (200–400 MPa, 3 min, 25 ℃) and subsequent refrigerated storage were analyzed in this study in order to evaluate the suitability of this non-thermal technology for preservation of fresh-cut Hachiya persimmons. The effects of high-hydrostatic pressure treatment on the integrity and location of carotenoids and tannins during storage were also analyzed. Significant changes, in particular diffusion of soluble compounds which were released as a result of cell wall and membrane damage, were followed using confocal microscopy. The high-hydrostatic pressure process also induced changes in physicochemical properties, e.g. electrolyte leakage, texture, total soluble solids, pH and color, which were a function of the amount of applied hydrostatic pressure and may affect the consumer acceptance of the product. Nevertheless, the results indicate that the application of 200 MPa could be a suitable preservation treatment for Hachiya persimmon. This treatment seems to improve carotenoid extractability and tannin polymerization, which could improve functionality and remove astringency of the fruit, respectively.

Effect of industrial freezing on the stability of chemopreventive compounds in broccoli

Broccoli (Brassica oleracea L. var. Italica) is largely consumed all over the world and has a high economic importance. Likewise, broccoli contains high levels of glucosinolates, carotenoids and total phenols, which are related with the prevention of chronic diseases. The present project's objective was to evaluate the effect of industrial freezing on the stability of bioactive molecules in seven commercial broccoli cultivars (Tlaloc®, Endurance®, Florapack®, Domador®, Steel®, Iron Man® and Avenger®). In general, industrial freezing increased the extractability of total glucosinolates, whereas total phenols remained constant in most broccoli cultivars. Likewise, broccoli subjected to industrial freezing showed higher levels of total carotenoids (∼60-300% higher) as compared with fresh broccoli. Results suggest that bioactive compounds in frozen broccoli would be more bioavailable than in raw.

High hydrostatic pressure processing reduces the glycemic index of fresh mango puree in healthy subjects

HHP-MP showed a significantly lower GI than the unprocessed-MP. HHP changes in viscosity and solubility could induce lower AUC values and greater glucose retardation indexes.

Analysis of the effect of high hydrostatic pressure treatment and enterocin AS-48 addition on the bacterial communities of cherimoya pulp

In the present study, pulp obtained from cherimoya pulp (Annona cherimola) was inoculated with epiphytic microbiota collected from cherimoya fruits, and supplemented or not with the circular bacteriocin enterocin AS-48 (50μg/g) and then packed under vacuum. Samples supplemented or not with enterocin were treated by high hydrostatic pressure (600MPa, 8min) and then stored at 5°C for 30days. The single AS-48 treatment only delayed microbial growth non-significantly (p>0.05). HHP treatment reduced microbial counts by five log cycles, but it did not prevent further growth of survivors by day 7. The combined treatment (AS-48+HHP) was the most effective, keeping bacterial cell densities at ≤1.5 log CFU/g for up to 15days. 16S rRNA gene pyrosequencing analysis was done on amplicon libraries from the growth on TSA plates seeded with ten-fold dilutions of pulp suspensions and incubated at 22°C for 24h. The results obtained are limited by the experimental conditions used in the study, and only concern the bacterial fraction that was selected by the TSA and growth conditions used. Pantoea (Pantoea agglomerans, Pantoea vagans) were the operational taxonomic units (OTUs) detected at highest relative abundance in bacterial biomass grown from control samples for the first 7days of storage, followed by Enterococcus gallinarum and Leuconostoc mesenteroides during late storage. The single HHP treatment significantly reduced the relative abundance of OTUs belonging to Pantoea and strongly increased that of endosporeformers (mainly Bacillus firmus and Bacillus stratosphericus) early after treatment, although Pantoea became again the predominant OTUs during storage. Samples singly treated with enterocin AS-48 revealed a strong inhibition of E. gallinarum as well as an early decrease in the relative abundance of Pantoea and an increased relative abundance of OTUs belonging to other Gram-negative species (mainly from genera Serratia and Pseudomonas). The strong microbial inactivation achieved by the combined treatment with enterocin and HHP reduced the levels of viable cells below detectable limits at days 0 and 1, and survivors recovered on TSA at day 7 were represented in >99% by B. firmus OTU. OTUs from endosporeformers were no longer detected during prolonged incubation, displaced by Pantoea spp., Erwinia billingiae and leuconostocs. Results from the present study indicate that HHP in combination with enterocin AS-48 is more effective in preserving the microbiological quality of cherimoya pulp during storage than the single HHP treatment.

Advanced retorting, microwave assisted thermal sterilization (MATS), and pressure assisted thermal sterilization (PATS) to process meat products

Conventional thermal processes have been very reliable in offering safe sterilized meat products, but some of those products are of questionable overall quality. Flavor, aroma, and texture, among other attributes, are significantly affected during such processes. To improve those quality attributes, alternative approaches to sterilizing meat and meat products have been explored in the last few years. Most of the new strategies for sterilizing meat products rely on using thermal approaches, but in a more efficient way than in conventional methods. Some of these emerging technologies have proven to be reliable and have been formally approved by regulatory agencies such as the FDA. Additional work needs to be done in order for these technologies to be fully adopted by the food industry and to optimize their use. Some of these emerging technologies for sterilizing meat include pressure assisted thermal sterilization (PATS), microwaves, and advanced retorting. This review deals with fundamental and applied aspects of these new and very promising approaches to sterilization of meat products.

High-pressure processing of berry and other fruit products: implications for bioactive compounds and food safety

Fruits contain a variety of nutrients and polyphenols that are associated with health benefits. Year-round availability of fresh fruits is limited due to perishability. Processing fruits extends shelf life. Individual quick-frozen fruit is the most common for fruits, but nowadays, processing fruits into beverages offers extended shelf life and new market opportunities. Conventional thermal processing is an effective method for producing safe, extended shelf life, and shelf-stable products, including beverages. However, the high temperatures negatively affect nutritive quality by destroying essential nutrients and biologically active "non-essential" components such as polyphenols. Therefore, novel technologies that can preserve nutrient quality while ensuring food safety are warranted. In this review, the application of high-pressure processing (HPP) for preserving nutrients and phytochemicals while ensuring microbiological safety in beverages and other foods containing fruits is discussed.