Effect of the Botanical Origin on Properties of RS3/4 Type Resistant Starch

An Attempt to Replace Pure Citric Acid with Natural Lemon Juice during Potato Starch Esterification

The application of chemical operations in food processing, in which pure chemical compounds are used to modify food ingredients, often raises social concerns. One of the most frequently modified dietary substances is starch, e.g., E1401-E1404, E1412-E1414, E1420, E1422, E1440, E1442, and E1450-E1452. An alternative solution to chemical treatments seems to be the use of raw materials naturally containing substrates applied for starch modification. Heating starch with a lemon juice concentrate can be considered a novel and effective method for producing starch citrate, which is part of the so-called "green chemistry". The modified preparations obtained as a result of potato starch esterification with natural lemon juice had a comparable degree of esterification to that of the esters produced with pure citric acid. In addition, the use of the juice doubled their resistance to amylolytic enzymes compared to the preparations made with pure acid. Replacing citric acid with lemon juice can facilitate the esterification process, and the analyzed properties of both types of modified preparations indicate that starch esters produced with pure citric acid can be successfully replaced by those produced using natural lemon juice, which may increase the social acceptance of these modified preparations.

Functionalization Methods of Starch and Its Derivatives: From Old Limitations to New Possibilities

It has long been known that starch as a raw material is of strategic importance for meeting primarily the nutritional needs of people around the world. Year by year, the demand not only for traditional but also for functional food based on starch and its derivatives is growing. Problems with the availability of petrochemical raw materials, as well as environmental problems with the recycling of post-production waste, make non-food industries also increasingly interested in this biopolymer. Its supporters will point out countless advantages such as wide availability, renewability, and biodegradability. Opponents, in turn, will argue that they will not balance the problems with its processing and storage and poor functional properties. Hence, the race to find new methods to improve starch properties towards multifunctionality is still ongoing. For these reasons, in the presented review, referring to the structure and physicochemical properties of starch, attempts were made to highlight not only the current limitations in its processing but also new possibilities. Attention was paid to progress in the non-selective and selective functionalization of starch to obtain materials with the greatest application potential in the food (resistant starch, dextrins, and maltodextrins) and/or in the non-food industries (hydrophobic and oxidized starch).

Enhancing physicochemical, rheological properties, and in vitro rumen fermentation of starch with Melastoma candidum D. Don fruit extract

The utilization of polyphenol-modified starch in ruminants has not undergone extensive exploration. This study aimed to investigate the impact of the complex formed between starch and Melastoma candidum D. Don fruit extract on physicochemical properties, phenol release kinetics in various buffers simulating the gastrointestinal tract, methane production, and post-rumen digestibility. The interaction between starch and M. candidum D. Don fruit extract significantly (p < 0.001) increased resistant starch and particle size diameter. The maximum phenolic release from complex between starch and M. candidum D. Don fruit extract, due to gastrointestinal tract-simulated buffers, ranged from 22.96 to 34.60 mg/100 mg tannic acid equivalent. However, rumen and abomasum-simulated buffers released more phenolic content, whereas the intestine-simulated buffer showed higher antioxidant activity (ferric ion-reducing antioxidant power). Furthermore, complex between starch and M. candidum D. Don fruit extract significantly decreased dry matter rumen digestibility (p < 0.001) and maximum methane gas production (p < 0.001).

Physicochemical Properties and Digestion Resistance of Acetylated Starch Obtained from Annealed Starch

One of the examples of physical starch modifications is the retention of a starch suspension in water having a temperature slightly lower than the pasting temperature (annealing). The aim of this study was to investigate the effect of the annealing process performed at various temperatures as the first stage of starch modification. The annealed starch preparations were then esterified using acetic acid anhydride. Finally, the annealed and acetylated starch preparations were determined for their properties. The annealing of starch before acetylation triggered changes in the properties of the modified preparations. It contributed to a higher degree of starch substitution with acetic acid residues and to the increased swelling power of starch. Both these properties were also affected by the annealing temperature. The highest resistance to amylolysis was found in the case of the starch preparation annealed at 53.5 °C and acetylated. The double modification involving annealing and acetylation processes increased the onset and end pasting temperatures compared to the acetylation alone. Similar observations were made for the consistency coefficient and yield point.

An Efficient Approach to Prepare Water-Redispersible Starch Nanocrystals from Waxy Potato Starch

Starch nanocrystals (SNCs) are a biodegradable polymer which has been widely studied and used in many fields. In this study, we have developed an efficient procedure for the preparation of SNCs. First, sodium hexametaphosphate (SHMP) and vinyl acetate (VAC) were used to modify waxy potato starch (WPS). Then, the modified starches were hydrolyzed with sulfuric acid to prepare SNCs. Results showed that SNCs prepared with modified starch had higher zeta potentials and better dispersion properties than the original starch. After modification, WPS still maintained its semi-crystalline structure, but the surface became rougher. SHMP-modified WPS showed a decrease in viscosity peak and an increase in gelatinization temperature. VAC-modified WPS showed increased swelling power. Additionally, SNCs prepared with VAC-modified WPS had better water redispersibility and dispersion stability than those from SHMP-modified starch—which will have broader application prospects in the field of safe and biodegradable food packaging.

Effect of the Esterification of Starch with a Mixture of Carboxylic Acids from Yarrowia lipolitica Fermentation Broth on Its Selected Properties

Potato starch was esterified with carboxylic acids contained in the fermentation broth from Yarrowia lipolitica yeast production. Various acid concentrations and various roasting temperatures were used to determine effects of process conditions on ester properties, including the number of acid residues attached to starch chains, starch susceptibility to amylolysis, and thermal characteristics of starch phase transitions. Study results demonstrated the effect of both the composition and the dose of the fermentation broth and of roasting temperature of starch on the number of acid residues attached to starch chains. Citric acid was more susceptible to esterification with starch (DS = 5.65%) compared to the α-ketoglutaric acid (DS = 0.12%). In the case of the latter, a higher degree of substitution was determined in the esters produced at higher roasting temperatures. The lowest digestibility (RS = 20%) was demonstrated for the starch esters with the highest degree of substitution with citric acid, whereas all starch esters showed decreased values of the thermal characteristics of pasting.

Organic Acids of the Microbiological Post-Culture Medium as Substrates to be Used for Starch Modification

This study aimed to identify the feasibility of producing highly-substituted starch esters via thermal modification of starch using a post-culture medium of Yarrowia lipolitica yeast. This manuscript describes a successful attempt at potato starch modification with a post-culture medium of Yarrowia lipolitica yeast with different concentrations of organic acids. Starch preparations produced by roasting (130 °C) and these produced by starch reaction with a synthetic acid mixture were compared in terms of the types and number of acid residues esterified with starch. The effectiveness of starch esterification was found to depend on medium composition and to be higher upon the use of a synthetic acid mixture. In addition, a higher reactivity with starch was demonstrated for citric acid than for α-ketoglutaric acid. The highly-substituted starch esters formed as a result of potato starch modification with post-culture medium were characterized by decreased values of thermal parameters of pasting characteristics, determined with a differential scanning calorimeter (DSC), and by compromised resistance to amylolysis. The intensity of these changes increased along with an increasing total percentage of starch ester substitution.