The impact of addition of pearl millet starch-germ complex in white bread on nutritional, textural, structural, and glycaemic response: Single blinded randomized controlled trial in healthy and pre-diabetic participants.

The rise of pre-diabetes at the global level has created a significant interest in developing low glycaemic index food products. The pearl millet is a cheaper source of starch and its germ contains significant amount of protein and fat. The complexing of pearl millet starch and germ by dry heat treatment (PMSGH) resulted an increase in the resistant starch content upto 45.09 % due to formation of amylose-glutelin-linoleic acid complex. The resulting pearl millet starch germ complex was incorporated into wheat bread at 20, 25, and 30 %. The PMSGH incorporated into bread at 30 % reduced the glycaemic index to 52.31. The PMSGH incorporated bread had significantly (p < 0.05)increased in the hardness with a reduction in springiness and cohesiveness. The structural attributes of the 30 % PMSGH incorporated bread revealed a significant (p < 0.05)increase in 1040/1020 cm-1 ratio and relative crystallinity. The consumption of functional bread incorporated with pearl millet starch germ complex reduced blood glucose levels and in vivo glycaemic index in healthy and pre-diabetic participants when compared to white bread. Hence, the study showed that the incorporation of pearl millet starch-germ complex into food products could be a potential new and healthier approach for improving dietary options in pre-diabetes care.

Modification of sorghum starch as a function of pullulanase hydrolysis and infrared treatment.

Papain-pretreated sorghum grains were modified by using pullulanase and infrared (IR) irradiation to decrease starch digestibility. An optimum synergistic effect was found under conditions of pullulanase (1 U/ml/5h) and IR (220 oC/3 min) treatment, which produced modified corneous endosperm starch with 0.022 hydrolysis rate, 42.58 hydrolysis index, and 0.468 potential digestibility. The modification increased amylose content and crystallinity up to 31.31 % and 62.66 %, respectively. However, the starch modification decreased its swelling power, solubility index, and pasting properties. FTIR revealed an increase in the ratio of 1047/1022 and a decrease in 1022/995, indicating the formation of a more orderly structure. The debranching effect of pullulanase was stabilized by the IR radiation amplifying its effect on starch digestibility. Therefore, the combination of debranching and infrared treatment could be an efficient method to produce 'tailor-made' starch, that can be further utilized in food industries to manufacture food for target population.

Influences of Partial Destruction of Ti-MOFs on Photo(electro)catalytic H2 Evolution by Dominating Role of Charge Carrier Trapping over Surface Area.

The design of water-stable photo and electrocatalysts of metal-organic frameworks (MOFs) for its promising catalytic applications at long-term irradiations or persisted current loads is extremely necessary but still remains as challenging. A limited number of reports on Ti-MOF-based catalysts for water splitting are only available to explain and understand the correlation between the nature of materials and MOFs array. Herein, spherical Ti-MOFs and corresponding partially annealed hollow core-shell Ti-MOFs (Ti-MOF/D) are designed and the correlation with their photo(electro)catalytic water splitting performance is evaluated. The switchable valence state of Ti for the Ti-MOF as a function of molecular bonding is the possible reason behind the observed photocatalytic hydrogen generation and light-harvesting ability of the system. Besides, the defect state, solid core-shell mesoporous structure, and active sites of Ti-MOF help to trap the charge carriers and the reduction of the recombination process. This phenomenon is absent for hollow core-shells Ti-MOF/D spheres due to the rigid TiO2 outer surface although there is a contradiction in surface area with Ti-MOF. Considering the diversity of Ti-MOF and Ti-MOF/D, further novel research can be designed using this way to manipulate their properties as per the requirements.

Monitoring bioaccessibility of iron and zinc in pearl millet grain after sequential milling.

The present study was to understand the effect of sequential milling on the distribution of inhibitory factors and their relation to iron-zinc bioaccessibility in the two pearl millet cultivars differing in grain shape and size. The studies revealed that the yield of decorticated grain and bran fractions differed between the cultivars. The initial bran fractions had lower iron content, which increased on increase of decortication duration (2.33-25.14 mg/100 g), while zinc did not follow this pattern. Among the inhibitory factors, polyphenols and phytic acid were low in the initial stages of milling and subsequently increased as the milling duration increased. Microscopic studies further confirmed that iron-zinc and inhibitory factors coexist in the same tissues of the grain. The ß- carotene was more concentrated in the middle layers of the pericarp. It was observed that iron bioaccessibility was the highest in the 4 min milling bran (7.7%, 3.34%) and final decorticated grain fractions (13.79%, 18.45%) of both the cultivars. Iron bioaccessibility could not be related to any particular inhibitory factors, in bran insoluble fibre and phytic acid were prominent while in decorticated grain galloyls, catechols and phytic acid were the maxima. In both the cultivars, zinc bioaccessibility was high in fractions with low phytic acid and insoluble fibre. The data presented suggest that 6 min decortication that removed around 10-15% of the bran had the highest iron and zinc bioaccessibility. The iron-rich bran fraction after appropriate processing can also be used in speciality food and thereby addresses the problem of micronutrient deficiency. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05072-x.

Cereal by-products as an important functional ingredient: effect of processing.

Cereal is a staple food and major nutrition source throughout the world. The cereal bran obtained from milling as by-product contains multiple benefits and health-promoting components such as dietary fiber, minerals, vitamins, polyphenols, and phytosterols. However, these by-products are usually undervalued and used in animal feed. To increase the functional and food value, processing techniques linked to improving nutritional characteristics, sensory properties and reducing the inhibitory factors have been developed. These processing techniques include mechanical, enzymatic and thermal processing. It aims to improve the functional properties, enhance the extractability of beneficial food ingredients, reduce the complex structure of the bran and improve solubility, decrease the content of inhibitory factors and improve the bio-accessibility of micronutrients. This review highlights the various technological interventions and application of appropriate processing techniques to process cereal bran for the isolation of functional food ingredient and thus utilizing the nutritious by-product of cereal processing industry.

Pearl millet minerals: effect of processing on bioaccessibility.

Pearl millet is an important source of dietary energy, and provides nutritional security for people in the third world countries, particularly in Africa and Asia. Previous studies have shown that pearl millet is an excellent source of micronutrients like iron and zinc. Owing to the presence of inhibitors like phytic acid, polyphenols, and fibres, the bioaccessibility of iron and zinc is very low in pearl millet diet. The present review is an attempt to highlight the localisation of minerals, phytic acid, and polyphenols in pearl millet grains, and various strategies that are being employed for the reduction of inhibitory factors. This review also appraises and gives an overview of the application of combinations of processing conditions and enhancers, that increases the bioaccessibility of iron and zinc either by way of reduction of inhibitory factors or prevention of binding of these inhibitory factors to minerals. The above strategies could be employed to provide better insights into the relevance of different processing methods, to help in the development of speciality foods with enhanced mineral bioaccessibility.

Assessment of inhibitory factors on bioaccessibility of iron and zinc in pearl millet (Pennisetum glaucum (L.) R. Br.) cultivars.

The variations in iron and zinc bioaccessibility as influenced by inhibitory factors in 13 pearl millet cultivars were evaluated. The results indicated that iron and zinc contents ranged between 5.59-13.41 and 2.11-5.19 mg/100 g. Polyphenols, flavonoids and phytic acid were highest in GHB744 (781 mg/100 g), HHB223 (116 mg/100 g) and HHB226 (1.080 g/100 g) respectively. Insoluble fiber content range from 9.36 to 12.89 g/100 g. Iron and zinc bioaccessibility was the highest in local Anantapur (17.95%) and GHB744 (15.19%) cultivar with low phytic acid. HHB226 exhibited high ß-carotene and phytase activity. In this study, the cultivars with high iron and zinc content also possessed high inhibitory factors which affected bioaccessibility. However, the bioaccessibility of iron did not seem to depend on the phytic acid: iron ratio alone. Further, a trend was observed in cultivars with low iron: zinc ratio had increased iron bioaccessibility. On the contrary, phytic acid: zinc ratio appears to play a significant role in zinc bioaccessibility. Certain cultivars with high iron content also had high phytase activity and ß-carotene content which could be exploited for further technological treatments to enhance the bioaccessibility of iron and zinc.

Influence of hydrothermal processing on functional properties and grain morphology of finger millet.

Finger millet was hydrothermally processed followed by decortication. Changes in color, diameter, density, sphericity, thermal and textural characteristics and also some of the functional properties of the millet along with the grain morphology of the kernels after hydrothermal processing and decortication were studied. It was observed that, the millet turned dark after hydrothermal processing and color improved over native millet after decortication. A slight decrease in grain diameter was observed but sphericity of the grains increased on decortication. The soft and fragile endosperm turned into a hard texture and grain hardness increased by about 6 fold. Hydrothermal processing increased solubility and swelling power of the millet at ambient temperature. Pasting profile indicated that, peak viscosity decreased significantly on hydrothermal processing and both hydrothermally processed and decorticated millet exhibited zero breakdown viscosity. Enthalpy was negative for hydrothermally processed millet and positive for decorticated grains. Microscopic studies revealed that the orderly structure of endosperm changed to a coherent mass after hydrothermal processing and the different layers of seed coat get fused with the endosperm.