High-pressure and thermal processing of cloudy hawthorn berry (Crataegus pinnatifida) juice: Impact on microbial shelf-life, enzyme activity and quality-related attributes

Quality of bee pollen submitted to drying, pasteurization, and high-pressure processing - A comparative approach

Bee Pollen is a valuable and useful natural food product that can be used for different purposes, among which medical ones. This matrix is deemed a superfood because of its chemical composition, which is rich in nutrients and possesses significant bioactivities, including antioxidant and microbiological properties. Nevertheless, the storage conditions and processing methods must be optimized to maintain their properties and maximise their application. This work investigates the best bee pollen conservation process and its impact on individual constituents. Monofloral bee pollen was analysed for 30 and 60 days after three different storage processes (drying, pasteurization, and high-pressure pasteurization). The results showed a decrease mainly in fatty acid and amino acid content for the dried samples. The best results were obtained with high-pressure pasteurization, maintaining the proteins, amino acids and lipids characteristics of pollen and the lowest microbial contamination.

Evaluation of Ultra-High-Pressure Sterilization in Terms of Bactericidal Effect, Qualities, and Shelf Life of 'Xinli No. 7' (Pyrus sinkiangensis) Pear Juice

In this study, ultra-high-pressure sterilization (UHPS) of Xinli No. 7 juice (XL7) was explored and optimized. A challenge to implement UHPS in juice as a full alternative to thermal treatment could be represented by the adoption of a pressure level of up to 500 MPa for 20 min at one cycle followed by the packaging in aseptic conditions. It was found that UHPS and HS treatments could effectively kill the microorganisms in XL7 juice but HS treatment would inevitably lose the nutritional quality in the juice, while UHPS treatment could better maintain the glyconic acid content, functional components, and antioxidant activity and reduce Browning degree and improve the stability of XL7 juice. The deterioration rate of UHPS and HS-treated XL7 juice increased with the increased storage temperature. The predicted shelf life of UHPS and HS-treated XL7 juice was 68 and 41 days at 4 °C, respectively. Collectively, UHPS treatment combined with low-temperature storage might be an effective way to prolong the shelf life of XL7 juice.

Non-thermal treatments of strawberry pulp: The relationship between quality attributes and microstructure

The relationship between quality attributes and microstructure in strawberry pulp after pasteurization (PS), ultrasound (US), electron beam irradiation (EB), and high pressure (HP) treatments was investigated. The results showed that US treatment decreased the viscosity to the lowest by 80.15% and increased the a* value, cloudy stability, and contents of titratable acid, total soluble solid, organic acids, total phenols, total flavonoids, and total anthocyanins (TAC), as well as its antioxidant capacity, due to the decrease in particle size, the destruction of microstructure, and the release of intracellular compounds. US and EB treatments could maintain the volatile compounds. The greatest deterioration in TAC and volatile compound content was found in the pulp treated with PS and HP treatments. HP treatment was beneficial to the enhancement of apparent viscosity, organic acids, and soluble sugar. These results provided insights into the enhancement of quality attributes in strawberry pulp due to the microstructure change.

The influence of non-thermal technologies on color pigments of food materials: An updated review

The color of any food is influenced by several factors, such as food attributes (presence of pigments, maturity, and variety), processing methods, packaging, and storage conditions. Thus, measuring the color profile of food can be used to control the quality of food and examine the changes in chemical composition. With the advent of non-thermal processing techniques and their growing significance in the industry, there is a demand to understand the effects of these technologies on various quality attributes, including color. This paper reviews the effects of novel, non-thermal processing technologies on the color attributes of processed food and the implications on consumer acceptability. The recent developments in this context and a discussion on color systems and various color measurement techniques are also included. The novel non-thermal techniques, including high-pressure processing, pulsed electric field, ultrasonication, and irradiation which employ low processing temperatures for a short period, have been found effective. Since food products are processed at ambient temperature by subjecting them to non-thermal treatment for a very short time, there is no possibility of damage to heat-sensitive nutrient components in the food, any deterioration in the texture of the food, and any toxic compounds in the food due to heat. These techniques not only yield higher nutritional quality but are also observed to maintain better color attributes. However, suppose foods are exposed to prolonged exposure or processed at a higher intensity. In that case, these non-thermal technologies can cause undesirable changes in food, such as oxidation of lipids and loss of color and flavor. Developing equipment for batch food processing using non-thermal technology, understanding the appropriate mechanisms, developing processing standards using non-thermal processes, and clarifying consumer myths and misconceptions about these technologies will help promote non-thermal technologies in the food industry.

Characterize the physicochemical properties and microstructure of pectin from high-pressure and thermal processed cloudy hawthorn (Crataegus pinnatifida) juice based on acid heating extraction

Physicochemical properties and morphological features of pectin in high-pressure-processing (JHPP) and thermal-processing (JTP) treated cloudy hawthorn juice were investigated based on acid heating extraction. Pectin from hawthorn juice was identified as low methoxy pectin (41.77%), which was significantly reduced to 34.56%-39.51% from JHPP, while pectin esterification degree (DE) from JTP increased to 45.58%, which can also be confirmed by Fourier transform infrared spectroscopy. In comparison to control, pectin linearity of JHPP and JTP significantly decreased with more highly branched-chains. However, no significate difference was observed in thermostability, crystallinity and main functional groups. Interestingly, a large number of aggregations was observed in JHPP pectin, and the intermodular distance of JTP pectin was enhanced, which was consistent with the results of viscosity, molecular weight and DE. These findings provided insights into utilization of hawthorn pectin and application of high-pressure processing (HPP) for improving quality property of fruit products by pectin modification.

Effect of citric acid/ pomelo essential oil nanoemulsion combined with high hydrostatic pressure on the quality of banana puree

In this work, the influence of citric acid & pomelo essential oil nanoemulsion (CA&PEN) assisted with HHP on microbial counts, oxidative enzyme activity and related quality of banana puree were examined. The total aerobic bacteria (TAB) counts of all groups decreased to 1.2 ∼ 2.52 lg CFU/g from 3.97 lg CFU/g, except the CA&PEN group, which was still below the detection level. CA&PEN combined with HHP (500 or 600 MPa, 5 min) succeeded in keeping TAB counts of banana puree below the detection limit for 3 months of cold storage. During 90 days of cold storage, the color, total phenolics, DPPH and ABTS antioxidant capacities were better conserved in acidified groups than non-acidified groups. In conclusion, CA&PEN assisted with HHP can be utilized to promote the inhibition of enzymatic browning and maintain the quality of banana puree, due to its reduced oxidative enzyme activity, low pH, strong antioxidant capacity and excellent color retention.

Characterization of the flavor, sensory quality and in vitro bioaccessibility in cloudy pomegranate juice treated by high pressure and thermal processing

BACKGROUND

Recently, cloudy pomegranate juice (PJ) has become popular due to its rich phenolic and health-promoting effects. The aim of the present work was to evaluate the application of high hydrostatic pressure processing (HPP), pasteurization (PT) and high-temperature short-time sterilization (HTST) on physicochemical properties (color, flow behavior, turbidity, sugars, organic acids, aroma and sensory evaluation) and in vitro bioaccessibility of total phenolics content (TPC), total flavonoids content (TFC) and phenolics of cloudy PJ.

RESULTS

Compared to HPP, thermal sterilization significantly increased the brightness (L*), redness (a*), total color difference (ΔE) and turbidity, and decreased the TPC and TFC. HPP maintained the volatile profile of cloudy PJ better, while thermal sterilization significantly changed the profile by decreasing alcohols 23.8-32.7% and increasing acids by 33.6%-182.8%. The bioaccessibility of flavonoids, phenolic acids and tannins in the control cloudy PJ after in vitro oral-gastric-intestinal digestion were 1.5%, 4.9%, and 9.0%, respectively, which were not significantly changed by different treatments.

CONCLUSION

These results contributed to promoting the color quality and health benefits of cloudy PJ rich in phenolics by optimizing the processing conditions in the food industry. © 2022 Society of Chemical Industry.

Comparative Genomic and Phylogenetic Analysis of Chloroplast Genomes of Hawthorn (Crataegus spp.) in Southwest China

The hawthorns (Crataegus spp.) are widely distributed and famous for their edible and medicinal values. There are ∼18 species and seven varieties of hawthorn in China distributed throughout the country. We now report the chloroplast genome sequences from C. scabrifolia, C. chungtienensis and C. oresbia, from the southwest of China and compare them with the previously released six species in Crataegus and four species in Rosaceae. The chloroplast genome structure of Crataegus is typical and can be divided into four parts. The genome sizes are between 159,654 and 159,898bp. The three newly sequenced chloroplast genomes encode 132 genes, including 85 protein-coding genes, 37 tRNA genes, and eight rRNA genes. Comparative analysis of the chloroplast genomes revealed six divergent hotspot regions, including ndhA, rps16-trnQ-UUG, ndhF-rpl32, rps16-psbK, trnR-UCU-atpA and rpl32-trnL-UAG. According to the correlation and co-occurrence analysis of repeats with indels and SNPs, the relationship between them cannot be ignored. The phylogenetic tree constructed based on the complete chloroplast genome and intergenic region sequences indicated that C. scabrifolia has a different origin from C. chungtienensis and C. oresbia. We support the placement of C. hupehensis, C. cuneata, C. scabrifolia in C. subg. Crataegus and C. kansuensis, C. oresbia, C. kansuensis in C. subg. Sanguineae. In addition, based on the morphology, geographic distribution and phylogenetic relationships of C. chungtienensis and C. oresbia, we speculate that these two species may be the same species. In conclusion, this study has enriched the chloroplast genome resources of Crataegus and provided valuable information for the phylogeny and species identification of this genus.