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Investigation of the prebiotic potential of rice varieties for Lactobacillus acidophilus bacteria

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Jamila Smanalieva at Technische Universität Dresden
Jamila Smanalieva
Janyl Iskakova at Kyrgyzstan-Turkey Manas University
Janyl Iskakova
Peter Fischer at ETH Zurich
Peter Fischer
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This study investigated the interaction of rice flour and two local strains of Lactobacillus acidophilus bacteria (LAB) from Kyrgyzstan used for the modification of a functional product for infant nutrition. White rice 2% w/w and a local variety of brown rice 2% w/w were used as prebiotic ingredients. The fermentation time of the samples ranged from 257 to 270 min to reduce the pH from 6.5 to 4.6. In the control product with 4% (w/w) sugar the fermentation was faster (257 min), however, gel setting G′/G″, measured with oscillation rheology, occurred at least after 182 min. Gel formation of the white rice-enriched samples was detected at 116 min and for brown rice-enriched samples at 168 min. The average pH of the samples at the end of 7 days of storage was in the following range: for control sample 4.68; for brown rice—4.29; for white rice—4.18. Within 7 days of storage, the viability of LAB in all samples remains high 87.71–95.40%. Additionally, supplementation with 2% white and brown rice reduced syneresis, i.e. increased the water-holding capacity, viscosity, gel strength, and sensory properties of the end product. Newly developed food with probiotic and prebiotic ingredients, regarding low sugar content, low acidity, and suitable consistency, was recommended for infant nutrition on the first 2 days of production.
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European Food Research and Technology (2021) 247:1815–1824
https://doi.org/10.1007/s00217-021-03754-6
ORIGINAL PAPER
Investigation oftheprebiotic potential ofrice varieties
forLactobacillus acidophilus bacteria
JamilaSmanalieva1 · JanylIskakova2· PeterFischer3
Received: 6 February 2021 / Revised: 4 April 2021 / Accepted: 10 April 2021 / Published online: 23 April 2021
© The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2021
Abstract
This study investigated the interaction of rice flour and two local strains of Lactobacillus acidophilus bacteria (LAB) from
Kyrgyzstan used for the modification of a functional product for infant nutrition. White rice 2% w/w and a local variety of
brown rice 2% w/w were used as prebiotic ingredients. The fermentation time of the samples ranged from 257 to 270min to
reduce the pH from 6.5 to 4.6. In the control product with 4% (w/w) sugar the fermentation was faster (257min), however, gel
setting G′/G″, measured with oscillation rheology, occurred at least after 182min. Gel formation of the white rice-enriched
samples was detected at 116min and for brown rice-enriched samples at 168min. The average pH of the samples at the end
of 7days of storage was in the following range: for control sample 4.68; for brown rice—4.29; for white rice—4.18. Within
7days of storage, the viability of LAB in all samples remains high 87.71–95.40%. Additionally, supplementation with 2%
white and brown rice reduced syneresis, i.e. increased the water-holding capacity, viscosity, gel strength, and sensory prop-
erties of the end product. Newly developed food with probiotic and prebiotic ingredients, regarding low sugar content, low
acidity, and suitable consistency, was recommended for infant nutrition on the first 2 days of production.
Keywords Lactobacillus acidophilus· Prebiotics· Rice· Milk acidification· Gel strength· Sensory properties
Introduction
Development of functional foods for paediatric nutrition
is an urgent task of modern nutrition science. According
to Gutiérrez, the perspectives in this field are oriented to
the manufacture of foods that allow the best care of the
intestinal microbiota and the regulation of the biochemi-
cal processes associated with the metabolism of nutrients,
which allow improving the immune response and promoting
the adequate physical and cognitive performance of babies
and children [1]. Fermented milk products with lactic acid
bacteria (LAB) are well known as probiotic foods [2]. The
LAB produce different antimicrobial compounds, such as
bacteriocins [3], lactic acid, hydrogen peroxide, benzoic
acid, fatty acids, diacetyl, and other low molecular weight
compounds, which have been shown to reduce inflammation,
enhance immune function [3, 4]. Probiotic bacteria from
local foods and also from normal intestinal microflora were
studied in the former Soviet Union in the 1970–1980s, for
the prevention and treatment of acute and chronic intestinal
infections, constipation, allergies, dysbacteriosis of various
origins, etc. In total 62 strains (17 strains L. bulgaricus, and
45 L. acidophilus) of LAB were isolated from indigenous
food Ayran from Kyrgyzstan [5]. The prebiotic properties
of these LAB strains were evaluated in antibiotic activity
against pathogens including Staphylococcus spp., Escheri-
chia coli, Enterobacter aerogenes, and Shigella sonnei [6].
Additionally, the isolated strains of Lactobacillus acido-
philus have shown proteolytic activity, so that children can
receive the essential amino acids from milk in an accessible
form. As part of these studies, a dairy product “Biolact’” was
developed [5]. Biolact, due to its low acidity and probiotic
properties, has been widely used in paediatric nutrition espe-
cially in hospitals from 1980 to the present day.
* Jamila Smanalieva
jamila.smanalieva@gmail.com
1 Department ofFood Production Technology, Technology
Faculty, I. Razzakov Kyrgyz State Technical University, Pr.
Aytmatov 66, 720044Bishkek, Kyrgyzstan
2 Environmental Engineering Department, Engineering
Faculty, Kyrgyz-Turkish Manas University, Pr. Aytmatov 54,
720044Bishkek, Kyrgyzstan
3 Institute ofFood, Nutrition, andHealth, ETH Zurich,
8092Zurich, Switzerland
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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  • Mar 2018
  • FOOD HYDROCOLLOID
Despite its excellent nutritional properties, unlike other cereals oat displays poor baking properties and therefore is mainly processed in products like rolled oats or serves as raw material for the functional ingredient β-glucan. During β-glucan production, a protein-rich fraction remains as a by-product. Functionalisation of this protein-rich oat-fraction and its application as a valuable food ingredient would improve the sustainability of the process. In the present study, oat protein-enriched cow's milk yoghurt was produced. The main foci were on the characterisation of techno-functional properties, as well as on the analysis of the organoleptic perception and sensory properties by a trained panel. Cow's milk yoghurt, following a traditional formulation with addition of skim milk powder (SMP), served as a reference. Oat protein was incorporated using two preparations: oat protein concentrate (OPC) and oat protein isolate (OPI). Fermentation of yoghurt enriched with SMP, OPC or OPI was monitored via pH-value, formation of lactic acid and rheological measurements. In addition, texture analysis and measurement of syneresis were performed and sensory properties were evaluated. Yoghurt containing SMP showed the highest strength in texture analysis but also a high rate of syneresis. Addition of OPC resulted in a product, which combines nutritional benefits with the sustainable use of the by-product of oat processing as well as improved product quality with respect to syneresis and sensory evaluation, especially mouthfeel. In case of OPI, strong sedimentation took place and high syneresis was observed. It is assumed that the compatibility of oat protein with milk proteins is low, which may be compensated by gelatinisation of starch during yoghurt production.
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Effects of Probiotics, Prebiotics, and Synbiotics on Human Health
Article
Full-text available
  • Sep 2017
The human gastrointestinal tract is colonised by a complex ecosystem of microorganisms. Intestinal bacteria are not only commensal, but they also undergo a synbiotic co-evolution along with their host. Beneficial intestinal bacteria have numerous and important functions, e.g., they produce various nutrients for their host, prevent infections caused by intestinal pathogens, and modulate a normal immunological response. Therefore, modification of the intestinal microbiota in order to achieve, restore, and maintain favourable balance in the ecosystem, and the activity of microorganisms present in the gastrointestinal tract is necessary for the improved health condition of the host. The introduction of probiotics, prebiotics, or synbiotics into human diet is favourable for the intestinal microbiota. They may be consumed in the form of raw vegetables and fruit, fermented pickles, or dairy products. Another source may be pharmaceutical formulas and functional food. This paper provides a review of available information and summarises the current knowledge on the effects of probiotics, prebiotics, and synbiotics on human health. The mechanism of beneficial action of those substances is discussed, and verified study results proving their efficacy in human nutrition are presented.
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Food Science, Technology and Nutrition for Babies and Children
Book
  • Mar 2020
Infants and children are regularly fed with processed foods, yet despite their importance in human development, these foods are rarely studied. This important book provides an exhaustive analysis of key technologies in the development of foods for babies and children, as well as the regulation and marketing of these food products. Contributors cover different aspects of food science and technology in development of baby foods, making this text an unique source of information on the subject. Food Science, Technology, and Nutrition for Babies and Children includes relevant chapters on infant milk formulas, essential fatty acids in baby foods, baby food-based cereals and macro- and micronutrients. This book also offers alternatives from the point of view of food technology for babies and children with special diet regimes associated to metabolic or enzymatic diseases such as allergy to casein, phenylalanine (phenylketonuria or commonly known as PKU) and gluten (celiac disease), or lactose intolerance. This book also addresses some nutritional aspects of babies and children in terms of the childhood obesity, child’s appetite and parental feeding. With its comprehensive scope and up-to-date coverage of issues and trends in baby and children’s foods, this is an outstanding book for food scientists and technologists, food industry professionals, researchers and nutritionists working with babies and children.
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Impact of pectin-rich orange fibre on gel characteristics and sensory properties in lactic acid fermented yoghurt
Article
  • Mar 2019
  • FOOD HYDROCOLLOID
Dietary fibre yields an additional benefit in terms of stabilisation of food structure or nutritional value, but may alter sensory properties in fibre-enriched foods. This study aims to investigate the impact of pectin-rich orange fibre on rheological, sensory and tribological properties of yoghurt gels. More specifically, the effect of the fibre particle size (coarse and fine) and fibre concentration (0.1 and 1.0%) is evaluated. Both, coarse and fine fibre accelerate structure formation during lactic acid fermentation. At low concentration fibre-enriched yoghurts exhibit rheological properties similar to the plain yoghurt and syneresis is decreased. At high concentration coarse fibre considerably reduces gel firmness whereas fine fibre additionally stabilises the casein network as a filler. This stabilising effect might be favoured by pectin, which leaches from orange fibre during mechanical and thermal pre-treatment and subsequently supports the bridging of casein micelles due to its calcium sensitivity. Depending on the criteria for classification of gels, fibre-enriched yoghurts show either strong or weak gel properties. Fibre addition causes alterations in sensory perception. A slight decrease in overall acceptance compared to the plain yoghurt is mainly related to a more compact texture and an increased particulate mouthfeel. Tribological data reveal that increased friction is mainly related to a reduced ability of coarse fibre yoghurt to immobilise water at high strain and that the protein (casein) network dominates lubrication properties in plain yoghurt.
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Impact of prebiotics on the rheological characteristics and volatile compounds of Greek yogurt
Article
  • Feb 2019
  • LWT-FOOD SCI TECHNOL
The objective of this study was to evaluate the effect of the addition of prebiotics (xylooligosaccharide, galactooligosaccharide, polydextrose, fructooligosaccharide, or inulin) on the quality parameters of Greek yogurt. Composition, rheological parameters, and the volatile compounds profile were evaluated. The effect of prebiotic addition was dependent on the type of the component used. The addition of galactooligosaccharide, polydextrose, and inulin resulted in more consistent (increase in k and decrease in n), elastic (increase in G′), viscous (decrease in tan δ) and firm products (increase in G * and z). In addition, the volatile compounds profile was diverse, with the appearance of isobutyric acid, 5-hydroxy-2,7-dimethyl-4-octanone, 2 (5H) -furanone and/or 2-hydroxy-3-pentanone, which contributes to the sweet aroma, sweet taste, and buttery flavor of the products. The addition of fructooligosaccharides had a negative impact on the rheological parameters, resulting in less consistent, elastic, viscous, and firm products. The addition of xylooligosaccharide resulted in products with intermediate characteristics. Therefore, galactooligosaccharide, polydextrose, and inulin proved to be technological and interesting alternatives for the manufacture of prebiotic Greek yogurts.
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