24 research outputs found
The potential and limitations for applications of oat proteins in the food industry
Received: February 1st, 2022 ; Accepted: March 4th, 2022 ; Published: March 14th, 2022 ; Correspondence: [email protected] proteins have gained high attractive popularity in the market as future protein
alternatives in various food products. The extracted oat protein fractions are characterised by a
relatively high protein content and a unique amino acid profile compared to other cereal grains.
From another aspect, the oat protein is separated unintentionally during the production of oat
flours, oat drinks, and oat flakes which encourages the incorporation of oat proteins in the food
industry to valorise the food wastes. Therefore, commercial oat proteins possess poor technofunctionality and water solubility in the usual environmental conditions for most food products;
therefore, modification of oat proteins functionalities is highly recommended. Several
modification methods, including chemical, physical and enzymatic, have been proposed to
improve the techno-functionality of native oat proteins and their biological activities. This review
highlights the nutritional value of the oat protein fractions, their techno-functional properties and
their food industrial challenging limitations. Additionally, it summarises several prospective
methods effective for boosting the functionality of oat protein fractions and broadening their
application in a range of food industries (bakery, dairy, meat, and their alternative products) with
an overview of their impact on humans, animals, and environmental health
Enrichment of the low-fat yoghurt with oat β-glucan and EPS-producing Bifidobacterium bifidum improves its quality
The addition of β-glucan or EPS-producing bacteria is mainly used to improve the
quality and the acceptability of low-fat yoghurt. The purpose of this study was to investigate the
effect of adding β-glucan, EPS-producing Bifidobacterium bifidum, or both on physical
properties, fermentation time, and organoleptic criteria of low-fat yoghurt, additionally to the
viability of L. bulgaricus and B. bifidum. Two types of low-fat yoghurt (1.5% fat) were prepared,
with the addition of standard oat β-glucan by 0.15% or without its addition. Each type of yoghurt
mixture was inoculated with two kinds of starters: traditional and probiotic (B. bifidum) culture.
The physicochemical properties, the count of viable bacterial starter culture, and the organoleptic
evaluation for all yoghurt types were evaluated after storage 24 h at 4 °C. Moreover, the
fermentation time was monitored. The incorporation of both β-glucan and EPS in yoghurt
resulted in the highest viscosity (13.7 mPa.s) and WHC (55.94%), besides to the lowest syneresis
(28.47%). The acidity and pH of the yoghurt samples were significantly affected (p > 0.05) by
the β-glucan addition. The yoghurt type Bifidobacterium glucan had the shortest fermentation
time (215 min), and the maximum viability of both B. bifidum (7.63 Log CFU g
-1
) and
L. bulgaricus (7.50 Log CFU g
-1
). The β-glucan had a pronounced effect on the overall
acceptability of yoghurt more than the EPS. In conclusion, enriching the low-fat yoghurt with oat
β-glucan and EPS-producing B. bifidum is the highest effective method for improving the
yoghurt’s quality and the viability of probiotics
Volatile organic compounds and their generation in sourdough
Received: October 30th, 2022 ; Accepted: April 1st, 2023 ; Published: April 14th, 2023 ; Correspondence: [email protected] technology is involved in bread making process for improving the sensory,
rheological, nutritional and shelf life characteristics of bakery products. More than 540 volatile
organic compounds (VOCs) and other flavour precursors belonging to the chemical classes, such as
aldehydes, ketones, esters, acids, alcohols, terpenes and others, have been identified in sourdoughs
and sourdough breads. The synthesis of VOCs is microbial species-specific, originating mainly
from fermentation process. VOCs can be used as indicators to characterize microbial processes.
Other additional sources of VOCs in sourdoughs are lipid oxidation and browning reactions, the
latter of which occurs during the production of dried starter cultures. The purpose of this article
is to provide an overview of the composition of VOCs and their effect on the sensory properties
of sourdough bread, and to describe the most common extraction methods of VOCs used in the
studies of sourdough and bread aroma profile. Long-term propagated sourdough VOCs have been
less studied compared to volatiles found in bread crust and crumb or sourdoughs started with
defined starter culture(s) due to their complexity and diversity in metabolic pathways, including
sophistication of the analytical methodology of VOCs. The relation between sourdough
microbiota and its volatile profile is not fully understood and therefore, their variability and
precise role as a bread flavour enhancer is not yet known in detail
Dietary fiber from underutilized plant resources—a positive approach for valorization of fruit and vegetable wastes
Agri-food industries generate enormous amounts of fruit and vegetable processing wastes,
which opens up an important research area aimed towards minimizing and managing them effciently
to support zero wastes and/or circular economy concept. These wastes remain underutilized owing
to a lack of appropriate processing technologies vital for their effcient valorization, especially for
recovery of health beneficial bioactives like dietary fibers. Dietary fiber finds wide applications in
food and pharmaceutical industries and holds high promise as a potential food additive and/or
as a functional food ingredient to meet the techno-functional purposes important for developing
health-promoting value-added products. Based on this, the present review has been designed to
support ‘zero waste’ and ‘waste to wealth’ concepts. In addition, the focus revolves around providing
updated information on various sustainability challenges incurred towards valorization of fruit and
vegetable wastes for extraction of health promoting dietary fibers
Compositional evaluation of hot-pressed rapeseed cake for the purpose of bioplastic production
Received: January 29th, 2021 ; Accepted: April 10th, 2021 ; Published: April 13th, 2021 ; Correspondence: [email protected] is widely cultivated for biodiesel or food-grade oil production. As the oil production process generates huge amounts of wastes and by-products (e.g. oil press cake and meal) that have relatively high crude protein content, valorisation as input material for protein-based bioplastics has a lot of potential. There is a limited number of studies undertaken on using rapeseed cake directly (without prior protein extraction) for biomaterial production, but the initial results have been very promising. As rape and turnip rapeseeds are also some of the most harvested crops in Estonia, the rapeseed oil press cake as a by-product is also available from local food-grade rapeseed oil production. In this regard, we investigated locally available rapeseed oil press cake for chemical composition and explored suitability for bioplastic production. The results indicate suitability for direct biomaterial production, meaning properties for biomaterial formation could be further explored.This work was supported by the European Union’s Horizon 2020
research and innovation programme under grant agreement No 810630: ERA Chair for Food
(By-) Products Valorisation Technologies of the Estonian University of Life Sciences
(VALORTECH). In addition, funding received from Mobility Plus ERA-Chair support
(Grant no. MOBEC006 ERA Chair for Food (By-) Products Valorisation Technologies of the
Estonian University of Life Sciences) is also gratefully acknowledged
Bioactives from agri-food wastes: present insights and future challenges
Sustainable utilization of agri-food wastes and by-products for producing value-added products (for cosmetic, pharmaceutical or food industrial applications) provides an opportunity for earning additional income for the dependent industrial sector. Besides, effective valorisation of wastes/by-products can efficiently help in reducing environmental stress by decreasing unwarranted pollution. The major focus of this review is to provide comprehensive information on valorisation of agri-food wastes and by-products with focus laid on bioactive compounds and bioactivity. The review covers the bioactives identified from wastes and by-products of plants (fruits, exotic fruits, vegetables and seeds), animals (dairy and meat) and marine (fish, shellfish seaweeds) resources. Further, insights on the present status and future challenges of sustainably utilizing agri-food wastes/by-products for value addition will be highlighted.The theme of this review article is based on the ongoing project- VALORTECH, which has received
funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No
810630
Application of Raw and Defatted by Supercritical CO₂ Hemp Seed Press-Cake and Sweet Grass Antioxidant Extract in Pork Burger Patties
Received: 29 May 2021; Accepted: 12 August 2021; Published: 16 August 2021.There is an increasing tendency toward the application of plant origin ingredients in meat
products. This study evaluates the physicochemical properties and oxidative stability of pork
burger patties produced with the addition of dried raw and defatted by supercritical CO2 extraction
hemp seed press-cake as protein-rich ingredients (1.5–2.0%) and sweet grass ethanolic extract (0.5%)
as a strong natural antioxidant. The main aim of using such a combination was to assess the possibility
of mitigating the negative effects of hemp seed press-cake, containing approx. 10% of highly
unsaturated oil, on the oxidation of meat products. The patties were compared with the control
sample (without additives) during storage on days 0, 4, 8, 15, and 21 at 4 °C in modified atmosphere
conditions. Plant ingredients reduced the lightness of pork patties, while their effects on other physicochemical
characteristics were insignificant. The patties with fully defatted hemp seed flour
showed the lowest grilling losses. Based on the measurement of thiobarbituric acid reactive substances,
raw hemp seed press-cake increased the oxidative rate of pork patties; however, remarkably,
the addition of sweet grass extract completely inhibited oxidation during the whole period of
storage. The sensory characteristics of the products were acceptable; however, the patties with sweet
grass extract received lower evaluation scores.Funding: This study was supported by the European Union’s Horizon 2020 research and innovation
programme project ERA Chair for Food (By-) Products Valorisation Technologies of Estonian University
of Life Sciences—VALORTECH (grant agreement No 810630); by the Estonian Ministry of
Education and Research programme “Support for research and development on resource valorization”,
ResTA focus theme “Food: Innovative valorisation of food and food ingredients“ research
project, and RESTA28 “Valorization of cereal and oilseed crops”; and by the Estonian Agricultural
Registers and Information Board, Innovation cluster MTÜ Liivimaa Lihaveis (project number
616116780016)
Assessment of chemical and sensory quality of unsalted and salted sweet cream butter during storage at different temperatures and time
Quality of butter depends on many factors such as quality of raw material, production method, ingredients used, type of packaging. Chemical changes taking place during storage of final product are also important. Extent of oxidation and the amount of free fatty acids in Estonian butter have not been investigated recently in experimental studies and have been evaluated at national level only with regard to intervention buying-in. The purpose of this work was to evaluate the quality of salted and unsalted sweet cream butter produced in continuous butter machine and stored at different storage temperatures and time periods. Three batches of salted and unsalted sweet cream butter were prepared and were stored at three different temperatures: at –20 °C for 24 weeks, at +5 °C for 12 weeks, at +20 °C for 8 weeks. Dry matter and salt content, peroxide value, acid value and organoleptic properties were evaluated. No major differences were found when comparing acid values and peroxide values at different storage temperatures. There were no significant differences between salted and unsalted butter samples and no age trends for the values. At all storage temperatures, the level of acid value (maximum value 0.81 mmol 100 g-1 fat) was lower than the upper limit established for high-quality butter (1.2 mmol 100 g-1 fat). The peroxide value (maximum value 0.050 meq per kg fat) was also lower than the upper limit established for high-quality butter (0.3 meq kg-1 fat) at all storage temperatures. After eight weeks of storage the sensory characteristics of butter – appearance, taste and flavour – scored at least 4 points or higher on 5 point scale that corresponds to high-quality butter
Impact of Weather Conditions and Farming Systems on Size Distribution of Starch Granules and Flour Yield of Winter Wheat
The size distribution of wheat-grain starch granules has an impact on the yield of finne flour. The aim of the study was to compare the impact of conventional (mineral fertilizers, pesticides) and organic farming treatments (cover crops, composted cattle manure) on (i) the size distribution of starch granules, (ii) the level of the first break whole and fine flour yield. The grain samples of winter wheat cv Fredis were taken from a long-term field crop rotation experiment established in 2008 at the Estonian University of Life Sciences in Tartu County (58°22′ N, 26°40′ E) on Stagnic Luvisol soil. The weather conditions during the grain filling period of winter wheat had a strong impact (p < 0.001) on the grain starch granule size distribution. The proportion of starch granules with a smaller diameter (C-type granules) was higher in years with a longer grain filling period. The size distribution of starch granules was not influenced by farming system. The increased proportion of C-type granules increased the fine flour yield significantly. Fertilisation with organic manure and twice with mineral nitrogen increased significantly the mean diameter value of different starch granules
The effect of ageing on chosen quality characteristics of skeletal muscles of Aberdeen Angus bulls
ArticleThe objective of the trial was to study the qualitative parameters of two muscles of
Aberdeen Angus bulls with 250–300 kg carcass weight. After slaughter, longissimus thoracis et
lumborum (LD) muscle and unseparated semimembranosus and adductor femoris(SMA) muscles
were removed from the chilled carcasses. Muscles were vacuum-packed and wet aged at +2 °C
for 10, 14, 18 and 20 days. Meat pH, electrical conductivity, shear force and colour were
measured in all ageing times. Two thermal treatment methods (sous-vide (SV) and grilling) were
used to determine cooking losses. The effects of muscles, ageing times and muscles by ageing
times interaction was found with two-factorial analysis of variance. The effects of muscles,
ageing times and muscle groups by ageing time interaction for raw and SV treated meat shear
force was significant. Ageing decreased SV treated meat shear force from day 10 (40.8 N) to
18 (29.7 N). Fresh and SV treated LD muscle was tougher compared to the SMA muscle group,
but SM showed a better response to the tenderness within 20 days of ageing. Redness and
yellowness value was higher in the SM group in comparison to LD. Muscles showed good colour
(lightness, redness and yellowness) stability within ageing for 20 days. No interactions were
found between muscle groups and ageing times for SV treated and grilled beef cooking losses.
However, SV treated meat lost more weight than grilled meat slices. The present study suggests
that the optimal ageing time for meat is 18 days when the grilled meat cooking loss is the lowest