It is common knowledge that the composition of hops secondary metabolites depends on several factors, among which the storage conditions. In recent years, many studies have been conducted to evaluate ...changes in the chemical composition of hop products in response to different storage temperatures both in aerobic and anaerobic environments. However, little knowledge exists regarding the storage of hop pellets under modified atmosphere for a very long period of time. The aim of this study is to evaluate the effect on hop quality parameters of different storage conditions on U.S. hop cultivar pellets (Chinook and Nugget) in a three-year trial. Storage in modified atmosphere (atmosphere saturated with 70% nitrogen (N2) and 30% carbon dioxide (CO2) and vacuum storage were tested at two different temperatures, 4 °C and 10 °C. In order to establish the best storage condition, the bitter acids content (HPLC-UV method), the essential oil content (steam distillation method) and the essential oil profile (GC-MS method) were determined and characterised at 0, 6, 12 and 36 months. No statistical differences were observed between samples stored under different atmospheres, while significant differences were highlighted as a result of the storage temperature, e.g. the alpha acids content at 4 °C was significantly higher (P = 0.002). The two hop cultivars showed different behaviours in the storage trial, suggesting that high alpha hop varieties, like Nugget, could be stored even at higher temperatures.
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•Hops can be stored for a long time under anaerobic conditions.•During storage, a slight decrease in bitter acids is observed, regardless of storage temperature.•Aromatic profile of hops stored for a long time, at 4 and 10 °C, changes significantly.•Shelf life of hop pellets is cultivar dependent.•To preserve alpha and beta acids hops can be stored at 10 °C.
Hop plants, produce edible sprouts, with interesting qualities, but their conservation is very poor. In this study, the effect of different treatments (freezing, blanching, sterilization and ...pasteurization) on two cultivars (Cascade and Nugget) of green hop sprouts were evaluated. Microstructure, physical analyses (texture and colour), enzymatic activity, DPPH activity and nuclear magnetic resonance (
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H-NMR) were utilized for the assessment of the product quality. Results indicated that freezing caused severe cellular and tissue damages. The results on colour and DPPH activity after treatments are cultivar-dependent. From
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H-NMR analysis, the samples with spectra more similar to raw one are blanched and blanched + freezing. In conclusion, blanched + freezing samples resulted the best choice for the technological and nutritional quality of hop sprouts and for a conservation of them; among final products obtained by thermal treatments, the pasteurized samples seemed to be the one that better preserves hop sprout quality.
In response to the market demand for low processed vegetables, high-pressure treatments (400,600 MPa; 1,5 min) were applied on zucchini slices and compared to a traditional blanching treatment. ...Histological observations, texture and color analysis, pectinmethylesterase (PME) and antioxidant (DPPH) activities were measured and compared to untreated samples. The histological observations revealed that the longer high-pressure treatments (5 min) led to more extended cell lysis and dehydration than the shorter ones (1 min) and blanching. High-pressure treatments resulted less effective than blanching on PME inactivation, with the best results obtained at 400 MPa for 1 min. Comparable texture parameters were observed for high-pressured and blanched samples. The negative correlation found between PME activity and the texture parameter ‘distance of the first peak force’ revealed an effect of PME on the texture recovery after treatments. High pressure led to a general browning of zucchini parenchyma and to DPPH drop. The correlations found between DPPH and color suggest the common nature of the phenomena. The influence of pressure and time on the studied parameters was revealed by two-way ANOVA. Principal component analysis clustered together the four high-pressure-treated samples, being clearly divided by blanched and untreated ones.
Background: Northern Italy has an enormous heritage of hop biodiversity that need to be exploited and studied. The preservation and valorization through the characterization of the existent ...biodiversity is a primary goal of the European Green Deal 2023–2030. The aim of this study was to acquire information on the biodiversity of Italian wild hops. Methods: Genetic characterization of sixty accessions was done resorting to Single Sequence Repeated (SSR) markers. Phytochemical characterization of wild hops was achieved using: (i) high-performance liquid chromatography with ultraviolet detection for bitter acids quantification, (ii) steam distillation for essential oils quantification and (iii) Gas Chromatography-Mass Spectrometry for the determination of the aromatic profile. Results: The eight SSR primers showed high Polymorphic Information Content (PIC), especially HlGA23. α-Acids reached values between 0 and 4.125. The essential oils analysis highlighted variability within the studied population, with some accessions characterized by important spicy fraction, and others by fruity and floral notes. Conclusions: The present study allowed the characterization of Italian wild hops and demonstrated an interesting biodiversity. Part of this biodiversity have been shown to be potentially suitable for use in brewing. Moreover, several genotypes could be used in breeding programs to obtain new more sustainable varieties.
Brewer’s spent grain (BSG) was used as a sustainable and healthy ingredient in two cereal bar formulations, with honey (H) and chocolate (C) used as the binding systems’ characterizing ingredients. ...The two bars, formulated using three levels of BSG (H1: 8.5%; H2: 12.7%; H3: 21.2%; C1: 3.9%; C2: 7.7%; C3: 15.5%) and stored for 20 days, were studied from a physicochemical perspective and compared to non-enriched control bars. The analysis showed that BSG enriched the bars with minerals, B vitamins, proteins, and fibers, meeting the required contents for the “high fiber” nutritional claim. Moisture content and water activity decreased with increasing BSG quantity and storage time. Higher BSG content increased flexibility in H bars after 7 days, while decreasing water content and increasing hardness in C bars at 1 storage day. Higher BSG levels darkened the samples’ color with little change during storage. In addition, a consumer sensory test was conducted. The results showed that providing information on BSG had little impact on liking, purchase intent, and sensory perception. In addition, under blind conditions, H bars were considered more natural and healthier than the C bars; however, these differences were not significant in the informed conditions. This study shows the potential use of upcycled ingredients in cereal bars and highlights the central role of the sensory experience on consumer appreciation, considering also information provision.
The olive is a long-lived evergreen tree, capable of regenerating itself from any part of the plant (pollard tree). This characteristic has allowed the olive trees to survive across the centuries ...until they become real natural monuments. The aim of this work has been to study the monumental “Olivo della Strega” (“Witch’s Olive tree”) olive tree, located in the olive orchard of Santissima Annunziata church, in Magliano (Grosseto, Italy), a tree with a special place in local history and folklore and with estimated age over 700 years. The morphometric data of leaf, fruit, stone and pollen were used to characterize the phenotype, while genetic diversity was assessed on the basis of microsatellite markers. The morphological and genetic analysis pointed to two clearly distinguishable parts in the “Olivo della Strega” tree, called sample left (SL) and sample right (SR). This ancient plant consists of two different genotypes: one part (SL) was identified as cv Frantoio and the other (SR) as an unknown genotype. Moreover, traditional (in vivo conservation) and advanced techniques (cryopreservation) have made conservation achievable to preserve its genetic heritage. In particular “Olivo della Strega” pollen was stored for 1 year in liquid nitrogen. The morphology of pollen grains, viability and germinability of fresh and long term cryopreserved pollen were observed at different times during preservation, without revealing significant differences.
Hops (Humulus lupulus L.) is a species that grows spontaneously in Corsica, but the characterization of this species in this territory has not yet been investigated. The main objectives of this study ...are to explore the features of wild hops from Corsica and to determine the effect of the island terroir on some cultivars in the first year of growth. A multidisciplinary approach consisting of the genetic analysis, morphological comparison and chemical characterization of essential oils was carried out on four wild Corsican hops and three hop cultivars grown in Tettnang, Germany and Corsica, France. The morphological and GC-MS analysis of Corsican wild hops, set cluster coastal samples apart from the one far from the coast. This dissimilarity is supported by the SSR analysis by two of the three coastal accessions. The genetics demonstrate a proximity between the European noble cultivar Tettnanger and the mountain Corsican wild hop from Corte. The morphological comparison between German hops cultivated in Tettnang and in Corsican soil, and the GC-MS characterization of their essential oils’ chemical profiles, show different features between year 0 and year +1 for each sample. This multidisciplinary approach highlights an acclimatization of hop cultivars to the Corsican terroir one year after planting.
Foliar fertilisation is known to influence the physiological response of
(hop plants), but its effect on the flavour profile of beer still has to be investigated. By comparing the effects of four ...fertilisation treatments, this study aims at determining whether different foliar fertilisation treatments have a significant impact on hop plants' aromatic quality and that of the beer produced. Hop cones harvested from each experimental treatment were brewed to obtain five single dry-hopped beers, which were subsequently analysed. Gas chromatography-mass spectrometry (GC-MS) and electronic nose (Cyranose 320) analyses were performed on the hop cones, while headspace solid-phase microextraction-gas chromatography-mass spectrometry HS-SPME-GC-MS, electronic nose and sensory analyses were carried out on the beers produced. The analyses not only allowed for a differentiation between the hops from the four fertilisation treatments and the control but also enabled a differentiation between the beers produced for their identification. Sensory evaluation revealed consumer preferences regarding the dry-hopped beers analysed, evidencing their distinctive features, including significant differences in both aroma and flavour.
(1) Background: The fig tree (
L.) is widely cultivated in the Mediterranean area and it produces fruits largely consumed in the Mediterranean diet. Previous studies have shown that this fruit ...represents a rich source of (poly)phenols, which are mainly located in the peel rather than the pulp. In our study, fig peel derived from twelve different cultivars located in Tuscany was assessed for its (poly)phenol profile. (2) Methods: The (poly)phenol characterization was performed through ultra-high performance liquid chromatography coupled to multiple-stage mass spectrometry. (3) Results: Twenty-eight (poly)phenolic compounds were quantified in the investigated fig peel. It was possible to observe an interesting variability in the (poly)phenol content among the twelve cultivars of fig peel. Rutin and 5-caffeoylquinic acid were the main compounds in the greenish fig peel, while cyanidin-3-
-rutinoside was the main component in the dark-violet fig peel. (4) Conclusions: fig peel could be used as a (poly)phenol-rich ingredient in several food products to increase the bioactive compound content of foods. Moreover, dark-violet peel could be considered potentially suitable as a natural food colorant.
In this study color, texture, starch-pectin, total antioxidant capacity, microbial count, and microstructure of HPP-treated Violina pumpkin cubes were evaluated. Samples were treated at six different ...pressures (100 to 600 MPa-HPP100 to HPP600) for 3 min. Moisture, total soluble solids, and pH showed no significant differences between untreated (UNTR) and treated samples. Pumpkin tissue showed great structural modifications as changes in cell size and shape, cell wall damage, increased cell wall thickness, cell detachment and dehydration, and calcium ions deposition mainly from HPP300 to 600. UNTR samples showed the highest value of maximum and minimum cell elongation, perimeter segment, and a more regular cell wall thickness whereas HPP600 showed the lowest values for all these parameters. A noticeable difference was observed in HPP600 samples, with a difference in terms of color (ΔE 11.3 ± 1.9) and hardness (87.4 ± 27.8 N) compared to the UNTR ones (194.9 ± 37.9 N) whereas treatments at other pressures changed less markedly the color and texture. HPP200 could ensure a higher amount of starch and pectin availability while HPP200 and HPP400 showed the highest total antioxidants capacity. High-pressure treatment from HPP400 to 600 gave the highest destruction of microorganisms but negatively influenced the structural quality as well as texture and microstructure.
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