Coffee leaf valorisation into functional wheat flour rusk: their nutritional, physicochemical, and sensory properties.

Coffee leaves are currently emerging as a promising agri-food resource rich in phenolics. This study aims to valorise coffee leaf powder (CLP) by incorporating it in refined wheat flour rusk formulations and analyse its physio-chemical, rheological, functional and sensory characteristics. The progressive replacement of CLP improved the dietary fibre (2.51 ± 0.2%), ash (1.09 ± 0.11%), and water absorption capacity (59.7 ± 0.1%) of the flours. It considerably enhanced the falling number and sedimentation values of the flour blends while decreased the loaf volume. Progressive increase in the dietary phenolics (232.21-435.19 mg/100 g), chlorogenic acid (6.0-7.5 mg/100 g), and ABTS antioxidant activity (963.89-1607.25 µMTEAC/g) of the rusks was observed upon CLP addition. Rusks with 3% CLP were found to have significantly acceptable physical and sensory characteristics. Thus, supplementation of CLP in rusk helps in valorising coffee leaves besides providing a functional bakery product to the coffee industry. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05927-z.

Quinoa germ-enriched pasta: Technological, nutritional, textural, and morphological properties.

Germ is the most significant component of quinoa having good nutritional value. Quinoa germ (QG), with balanced amino acid profile and unsaturated fatty acid, is a unique ingredient for human nutrition. In present study, pasta supplemented with QG was characterized for physical, nutritional, morphological, and textural properties. Dough rheology showed increased farinograph water absorption and decreased dough stability with the addition of QG. Addition of QG up to 30% significantly improved the pasta protein content from 13.55% to 20.55%. The substitution of QG to pasta showed decrease in whiteness index and increase in optimum cooking time, swelling index, cooked weight, and cooking loss. It is reported that 20% QG supplement pasta was found to be acceptable; beyond, this level the pasta quality was inferior. Firmness value of pasta significantly increased up to 20% supplementation of QG from 157 to 178 g. The micrographs of pasta with the addition of QG observed increased protein matrix around the starch granules. The results inferred that the QG can serve as a potential functional ingredient for the development of nutritionally enhanced pasta for food industry. PRACTICAL APPLICATION: Quinoa germ (QG) is concentrated source of nutrient with unique nutrition and alternative source of protein. Pasta is the one the popular and fast-growing food in world and explored for enhancement of its nutritional composition to target a larger population with specific nutrient demand. Hence, pasta becomes important vehicle for the supplementation. Developed QG-enriched high-protein pasta will help industry to produce nutritious products at large scale.

Correction: Study on the utilization of by-products of wheat milling industry for the development of biodegradable plates.

[This corrects the article DOI: 10.1007/s13197-023-05738-8.].

Study on the utilization of by-products of wheat milling industry for the development of biodegradable plates.

The present study aims at utilizing wheat bran and resultant atta to produce biodegradable-edible plates as an alternative to plastic plates. The edible plates were prepared using different combinations of wheat bran and resultant atta in different ratios viz., WB, 90:10 (WR10); 80:20 (WR20), 70:30 (WR30). Using farinograph, it was observed that the higher the bran higher the water absorption. The doughs from the blends were prepared with water at two different temperatures (100 °C and 27 °C), sheeted, moulded and baked. Plates produced from WR10, 20, 30 were analysed further and based on break test, leak test and sensory WR30 was chosen as the best. WR 30 was found to leak at 23.01 ± 0.24 min with hot water and 85.42 ± 0.11 min with water at room temperature. Moisture, ash, fat, protein, and total dietary fibre content was 4.3 ± 0.016, 4.90 ± 0.08, 3.86 ± 0.075, 16.06 ± 0.082 and 26.92 ± 0.166 respectively. Shelf-life predicted for plate was 250-285 days based on MSI studies done.

Effect of heat treatments on quinoa germ quality and its storage study.

Quinoa is a potential crop to address the situation as it offers a plethora of benefits as it is nutritionally rich and can adapt to extreme climatic and salt conditions. Quinoa germ consists of almost 25-30% of whole grain. Quinoa germ obtained using roller milling has remarkable nutritional properties with high protein, fat and mineral content. Presence higher fat content limits shelf-life of quinoa germ. The objective of the present investigation is to study the effect of different treatment on stabilization of quinoa germ and its storge study. Quinoa germ was subjected to microwave and infrared treatment for shelf-life extension. Colour properties of the germ has not changed drastically by both treatments. Sorption behavior of quinoa germ stored at different RH was studied and results showed typical sigmoid curve for all samples. Sorption studies revealed that treated quinoa germ were stable at 64% RH. The storage study was carried out at accelerated conditions using PET/PE packaging material. Based on the results of the study, it can be inferred that the quinoa germ can be kept up to three months at accelerated conditions. Study demonstrated that microwave treatments of quinoa germ showed highest shelf life of three months at accelerated conditions.

Application and effect of hybrid grinding techniques on the quality of stone chakki atta (whole wheat flour) and flat bread.

Industrially packaged whole wheat flour (atta) is manufactured in motorized stone chakkis, which consumes more electric power. Present study is aimed towards evaluating the effect of hybrid grinding technique of wheat using roller mill on its grinding characteristics and quality of chakki atta and chapatti. Wheat was passed through the pair of first break rolls in MLU 202 with the roll gaps of 1 and 0.9 mm for two different samples. Electrical parameters for grinding energy were compared and the pre-milled wheat was ground in the stone chakki. Atta obtained from 2 different variations and control stone chakki atta were compared for physico-chemical, rheological and chapati making quality. Damaged starch increased from 15.25 for control atta to 17.3% for 0.9 mm sample, whereas, farinograph water absorption increased from 75.9 to 78.9% respectively. Chapatis were prepared and sensory studies were carried out. Chapati colour was found to be brighter for 0.9 mm sample.

Effect of grinding techniques and supplementation of quinoa on the carbohydrate profile of tortillas.

With an aim of studying the implication of the milling interventions and supplementation of non-wheat grains on the effect of the carbohydrate digestive profile of wheat flour the present study was conducted. Quinoa grain was selected for the study due its higher protein content and better amino acid profile than that of cereal grains. Milling of grains to produce atta (whole wheat flour) was carried out using traditional method of stone chakki mill and the other method of separation and recombination of different stream using roller mill. The atta flour was then supplemented with the quinoa flour in different combinations and the physico-chemical, rheological and product making characteristics were studied. The milling technique has an impact on the damaged starch with the difference of around 6% across the flour samples which further impacted the water absorption capacity and the gelatinization temperature of the flour. Carbohydrate digestive profile of the prepared tortillas have shown significant difference when the atta from roller mill substituted with quinoa flour upto 15%. Starch digestibility index of stone chakki atta was higher SDI (78.71) than that of roller milled quiooa supplemented flours (38.52 and 36.74). The rapidly digestible sugar decreased and the slow digestible sugar increased as compared to stone chakki atta tortillas which combinedly is responsible for lower glycaemic index. In the commercial point of view this will open a new avenue for food manufacturer to produce value added and healthy products from quinoa. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05365-9.

Effect of Fenugreek fiber on Rheological and chapati making quality of whole wheat flour.

Increase in awareness of consumers and demand has led to the development of various fibre rich food products from different fiber source. In the present work novel roller milled fenugreek fiber rich fraction (FFRF) rich in galactomannans was used for the development of high fiber chapati. Farinograph water absorption and dough stability increased with increase in the addition of FFRF in blends. The creep measurement results showed reduction in the maximum creep compliance and viscoelastic compliance while the zero shear viscosity showed the increasing trend with the increase in the addition of FFRF. The pliability of chapatis significantly decreased on addition of FFRF. The sensory evaluation concluded that the chapati with 10% FFRF is acceptable. The shear force value of chapatis prepared from the control and WWF-FFRF blends were decreased as the storage time increased showing brittleness in the chapatis. The micrographs of an outer layer of chapati (crust) showed partially gelatinized starch. The crumb micrographs of the WWF-FFRF blends chapatis showed large and small starch granules coated with galactomannans gums, and this coating increased with increased addition of FFRF. The composition of 10% fenugreek fiber chapati contained higher amount of minerals, insoluble and soluble dietary fiber compared to that of control sample. The in vitro starch digestibility of formulated chapati showed significant decrease in the values.

Milling interventions for the production of atta for Indian flat bread with low carbohydrate digestibility.

Study was aimed to produce atta for chapati, an Indian flat bread with low carbohydrate digestibility through different milling interventions; processing and formulating a functional ingredient mix (FM). Granulation, physico-chemical, rheological and chapati making characteristics of chakki atta, CA (control), roller mill atta (RA); RA replaced with 5, 10 and 15% FM (5, 10 and 15% RAFM) were evaluated. RA and RAFM samples showed lower water absorption, higher dough stability, pasting temperature and peak viscosity than CA. Evaluation of carbohydrate digestive profile showed differences in the pattern of carbohydrate digestibility and glucose release between the chapatis prepared from CA, RA and 10% RAFM. Rapidly available glucose (RAG), an indicator of glycemic response in vivo, was found to be lower in the 10% RAFM than CA. It can be concluded that milling interventions and compositional differences together determine the carbohydrate digestibility of the atta.

Effect of grain moisture content during milling on pasting profile and functional properties of amaranth fractions.

Evaluation of functional properties of milled fractions of grain amaranth may be useful to decide the end uses of the grain. Hence, pasting profiles of amaranth fractions obtained by milling the grains at different moisture contents were studied in relation with their starch profile and also with their swelling power and solubility indices. It was observed that, for flour fraction, the viscosity parameters were lowest at 14-16 % moisture content. Swelling power and solubility indices of the samples varied as a function of grain moisture content. The middling fraction also showed similar pasting pattern with the variation of grain moisture content. The seed coat fractions showed higher gelatinization temperature compared to that of fine flour and middling fractions. However, starch content of the fine seed coat fraction was comparable with that of the flour and middling fractions. The coarse seed coat fraction showed lower viscosity parameters than the other samples. Viscosity parameters correlated well among themselves while, they did not show significant correlation with the starch content. However, the viscosity parameters showed negative correlation with the soluble amylose content. The study revealed that, the fractions obtained by milling the grains at different moisture content show differential pasting profiles and functional properties.

A study on rheological characteristics of roller milled fenugreek fractions.

Fenugreek seeds were fractionated by roller milling to get various fractions. The roller milled fractions and whole fenugreek flour (WFF) were evaluated for the flow behavior and time-dependent flow properties using a rotational viscometer at the temperatures of 10-60 (0)C. The samples subjected to a programmed shear rate increase linearly from 0 to 300 s(-1) in 3 min and successive decrease linearly shear rate from 300 s(-1) to 0 in 3 min. The roller milled fractions and WFF paste exhibited non-Newtonian pseudoplastic behavior. Difference in hysteresis loop area was observed among the roller milled fractions and WFF, being more noticeable at lower temperatures. Power law and Casson models were used to predict flow properties of samples. The power law model described well the flow behavior of the roller milled fractions and WFF at temperatures tested. Except flour (FL) fraction, consistency coefficient, m, increased with the temperature both in the forward and backward measurements. The roller milled fractions and WFF exhibited rheopectic behavior that increased viscosity with increasing the shear speed and the temperature. For all the sample tested, initial shear stress increased with increase in shear rate and temperature.

Rheological, physico-sensory, nutritional and storage characteristics of bread enriched with roller milled fractions of black gram (Phaseolus mungo L.).

Black gram grains were fractionated using roller flour mill. Effect of combination of additives (CA) namely dry gluten powder, sodium stearoyl-2-lactylate, fungal α-amylase on the rheological and bread making characteristics of wheat flour partly replaced with roller milled fractions of black gram was studied. With increase in the addition of straight run flour (SRF), protein rich fraction (PRF), protein and fiber rich fraction (P&FRF) from 0 to 20 %, fiber rich fraction, FRF (0-15 %), the farinograph water absorption increased and dough stability decreased; amylograph pasting temperature increased and peak viscosity decreased; bread volume decreased and crumb firmness value increased indicating adverse effect of these fractions on the rheological and bread making characteristics of wheat flour. Sensory evaluation showed that breads were acceptable only up to the level of 15 % for SRF, PRF & P&FRF and 10 % for FRF. However, when CA containing dry gluten powder, sodium stearoyl-2-lactylate and fungal α-amylase was incorporated the overall quality of the products improved. Use of these fractions increased the protein and fiber contents of bread by 1.24-1.66 and 1.48-3.79 times respectively. The results showed that possibility of utilising roller milled black gram fractions along with CA to improve the taste, texture and nutritional quality of bread.

Roller milling process for fractionation of fenugreek seeds (Trigonella foenumgraecum) and characterization of milled fractions.

The fenugreek seed is the richest source of soluble and insoluble fiber and also known for its medicinal and functional properties. The major objective of this present study is fractionation of the fenugreek by roller milling method and characterization of roller milled fractions. The effects of moisture conditioning on fenugreek roller milling were studied using standard methods. The results observed were increase in coarse husk from 33.75-42.46 % and decrease in flour yield from 49.52-41.62 % with increase in addition of moisture from 12-20 %. At 16 % conditioning moisture, the yield of coarse husk was 40.87 % with dietary fiber and protein content of 73.4 % and 6.96 % respectively. The yellowness value (b) for the coarse husk (29.68) found to be lowest at 16 % conditioning moisture compared to the other coarse husk samples, showing maximum clean separation. The fiber fractions showed the viscosity of 6,392 cps at 2 % w/v concentration. The flour fraction was higher in protein (41.83 %) and fat (13.22 %) content. Roller milling process of fenugreek was able to produce > 40 % of coarse husk with 73.4 % dietary fiber (25.56 % soluble & 47.84 % insoluble) and > 48 % flour with 41.83 % protein content, where as the whole fenugreek contained 22.5 % protein & 51.25 % dietary fiber. Thus roller milling has proved to be a valuable method for the fractionation of fenugreek to obtain fiber and protein rich fractions.

Effect of co-milled wheat, green gram and barley on the rheological and quality characteristics of cookies.

Studies were carried out on the co-milling of wheat (W), green gram (GG) and barley (BR) grains using a roller milling system. The co-milled straight run flours obtained by varying proportions of wheat, barley and green gram WGGBR-1 (90:5:5), WGGBR-2 (80:10:10) and WGGBR-3 (70:15:15) were used in the cookie baking experiments. As the amount of GG and BR increased in blend, water absorption increased (56.5-58.4%) and dough stability and extensibility values decreased (104-92 mm). Hardness of cookie doughs and spread ratio (7.70-6.00) of cookies decreased and breaking strength values increased from 2900 to 3700 g in cookies made using co-milled blends WGGBR-1, WGGBR-2 and WGGBR-3. The highest breaking strength value (3700 g), large islands, gummy mouth feel and lowest overall quality score of 51.5 were recorded for cookies made with blend WGGBR-3 indicating that the cookies had unacceptable hard texture. The optimum blend for cookies was WGGBR-2 (80:10:10) and the cookies possessed slightly small islands, crisp, light texture and a pleasant taste. These cookies had 12.30 and 8.00% protein and dietary fibre as against the control cookie values of 8 and 4%, respectively. The in vitro protein digestibility of the control cookies was 61% and it was 51% for cookies made with WGGBR-2 blend.

Roller milling fractionation of green gram (Vigna radiata): optimization of milling conditions and chemical characterization of millstreams.

In the view of recent growing interest in utilization of grain fractions as food ingredient, present investigation was carried out to evaluate the roller milling potential of green gram. The effect of conditioning moistures on green gram roller milling were studied. The results showed decrease in flour yield from 85.56 to 58.74 % with increase in conditioning moisture from 10 to 16 %. Higher yield of flour was observed from the first (C1), second (C2) and third (C3) reduction passages; whereas, the first (B1), second (B2) and third (B3) break passages produced less flour. The distribution of protein, dietary fiber, ash and fat in different flour streams and by-products from roller milled fractions of green gram showed wide variation. The protein content increased with increasing numbers of breaks and reductions in the flour streams. The highest protein content of 30.16 % was found in bran duster flour and lowest (11.32 %) in fine seed coat. The protein content of break streams was found lower than reduction streams. The dietary fiber content of coarse seed coat was highest (71.17 %) followed by the fine seed coat (57.22 %). The microstructure studies of milled fractions of green gram showed more deformed and damaged starch granules in reduction flour streams than break flour streams.

Effect of flour particle size on microstructural, rheological and physico-sensory characteristics of bread and south Indian parotta.

Wheat flour fractioned by sieving into four different particle size fractions namely finer fractions (<75 and 75-118 µm), coarser fractions (118-150 and >150 µm) were analyzed for their chemical, rheological, bread & parotta making characteristics. The finer fractions had lower ash, higher dry gluten, damaged starch and sodium dodecysulphate (SDS)-sedimentation value than the coarser fractions. The flour from finer fractions gave bread with best sensory and textural attributes. The parottas from finer fractions showed significantly higher sensory scores for colour, texture, layers, mouthfeel and overall quality score than the coarser fractions. In the micrograph of finer flour fractions, higher number of loosened single starch granules than the aggregates of starch and protein matrix were seen as compared to coarser fractions. These studies indicate that the flour from the finer fractions produce higher quality bread, parotta owing to the presence of higher damaged starch content, quantity and quality of protein in these fractions than coarser fractions.

Chemical, rheological and bread making characteristics of bran duster flours from roller flourmills.

Bran dusters are used in the wheat flour milling process to increase flour extraction rate. Chemical, rheological and bread characteristics of bran duster flours (BDR1, BDR2, BDR3) and straight run flour (SRF) obtained from two commercial roller flour mills were analyzed. Important chemical characteristics such as ash, dry gluten content, sedimentation value, damaged starch and falling number of bran duster flours were determined. Rheological behavior was tested using farinograph and alveograph equipments. The results showed an increase in ash, dry gluten content and Zeleny's sedimentation value for bran duster flours compared to SRF. Rheological characteristics indicated higher farinograph dough development time and stability values for bran duster flours. Alveograph characteristics indicated higher extensibility and lower elasticity values for bran duster flours. Over all quality score of bread for BDR1 from A and B roller flour mills ranged from 73.4 to 74.7, BDR2 (79-81.8), BDR3 (69-70.4) as against SRF (85.4-86.3).

The cumulative ash curve: a best tool to evaluate complete mill performance.

Slick test is carried out by a flour miller to qualitatively segregate the flour from different streams in a roller flour mill. This test is done manually by pressing flour samples on tray using thin bladed paddle (the slick) and inspecting color or dress of the sample. However, the test is subjective and totally depends on human judgment. Cumulative ash curve relates to cumulative flour ash content and cumulative flour yield, which could help a flour miller to be more precise while selecting flour streams for different needs. In this study, cleaning and conditioning of wheat was carried out in the pilot plant of International School of Milling Technology (ISMT). Further, roller flour milling of wheat was done. Flour from different streams (four breaks, five reductions) was collected. Each flour stream was analyzed for ash content using standard AACC methods. The analytical values of ash content were used to plot the cumulative ash curve. It was found that ash content increased in the break passages from first to last break, with exception of first break (ash content 0.71%). An increase in percentage of ash was observed in the reduction passages (C1 to C5), however, C3 ash (0.76%) was slightly higher than that of C4 (0.65%). Higher yield of flour with minimum ash content was obtained from the front reduction passages C1 and C2; whereas, the break passages and the tail end reduction passages produce less flour with higher ash content.