Alternative Protein Source Research Articles

The Impact of Freeze-Dried Tenebrio molitor Larvae on the Quality, Safety Parameters, and Sensory Acceptability of Wheat Bread.

The research context involves analyzing the potential benefits derived from integrating insect protein into everyday food items. Utilizing methods consistent with established food science protocols, wheat bread was prepared with variations of 0%, 5%, 10%, and 15% Tenebrio molitor larvae powder, derived from larvae cultivated on brewery spent grain. A substrate selected for its superior nutritional content and a substrate with agar-agar gels were used. The tests included basic bread tests; sugar, acrylamide, amino, and fatty acid (FA) tests; and sensory acceptability. The results have shown that the acrylamide levels in bread with larvae remained below harmful thresholds, suggesting that using T. molitor can be a safe alternative protein source. The incorporation of powdered T. molitor larvae (p-TMLs) into bread was observed to increase certain sugar levels, such as glucose, particularly at higher larval concentrations. The addition of T. molitor significantly raised the protein and fat levels in bread. The inclusion of larvae enriched the bread with essential amino acids, enhancing the nutritional value of the bread significantly. The FA profile of the bread was altered by the inclusion of p-TMLs, increasing the levels of monounsaturated FAs. Despite the nutritional benefits, higher concentrations of larvae decreased the sensory acceptability of the bread. This suggests that there is a balance to be found between enhancing the nutritional content and maintaining consumer appeal. These findings highlight the potential for using p-TMLs as a sustainable, nutritious ingredient in bread making, although the sensory qualities at higher concentrations might limit consumer acceptance.

Assessment of Proximate, Mineral, Phytochemical and Antimicrobial Properties of Brassica oleraceae L. Leaf Concentrates

Food insecurity, ill health due to microbial infection and malnutrition have led to the search for alternative and affordable measures to address food shortage problems and associated health issues worldwide. This provides an opportunity to investigate the use of plants as a remedy. A fresh sample of Brassica oleracea was selected for the study; the sample was obtained and identified at the Botany Department of the University of Ibadan, washed before being processed into the leaf concentrate and assessed for proximate, mineral, phytochemical and antimicrobial potentials using the standard methods. The results of proximate analysis in g/100g showed; moisture; 8.80±0.16, Ash; 1.38±0.10, crude fat; 4.66±0.12, crude protein; 35.52±0.3, crude fibre; 3.16±0.06 and NFE; 46.45±0.23. The mineral analysis in mg/100g showed Na; 35.81±0.23, K; 3.37±0.01, Ca; 24.71±0.02, Mg; 0.24±0.00, P; 0.91±0.00, Fe; 0.90±0.01, Zn; 0.50±0.00, Cr; 0.10±0.00, Ni; 0.00, and Cu; 0.02±0.01. The sample contains some bioactive phytochemical compounds like steroids, anthraquinones terpenes, and coumarin. The sample extracts also showed antimicrobial potential against the ten selected microbes. The study conducted so far on the selected sample revealed that the sample will be viable ingredients in food formulation, pharmaceutical raw materials and alternative sources of protein.

Processing, Uses and Constraints to Edible Insect Consumption in Ekiti State, Nigeria

Insects have played an important role in the history of human nutrition, especially as important sources of high protein. This study investigates the processing, uses and constraints to edible insect consumption in Ekiti State. The study area was stratified based on ecological zones into; tropical rainforest and derived savanna. Four local government areas were selected from each ecological zone, and two villages were selected from each LGA. Structured questionnaires were administered to twenty (20) respondents in each of the eight selected villages. Field observations revealed that the majority of the respondents were female (65%), with (48%) of them above 30 years and (41%) of the respondents were farmers. The result revealed that six (6) insects were consumed by the respondents in the study area, with Marcrotermes nigeriensis (31%) being the most consumed insect, followed by Rhynchophorus phoenicis (22%), Cirina forda (20%), while Gryllotalpa africana (6%) was the least consumed insect. The result on the functional values of edible insects revealed that (32%) of the respondents stated that edible insects are rich in protein, while (25%) consume insects as meat for a cheaper alternative source of protein. Another (18%) stated that edible insects are medicinal. The result shows that the commonly used processing method by the respondents is roasting (44%). Lack of knowledge of the nutritional values and seasonal availability were the major challenges against the consumption of edible insects in the study area. The study recommends creating public awareness about the health and nutritional benefits of these edible insects, alongside adopting improved processing and preservation techniques.

90-day oral toxicity study in rats of a protein-rich powder derived from Xanthobacter sp. SoF1.

Xanthobacter sp. SoF1 (SoF1) is an autotrophic hydrogen-oxidizing bacteria that produces protein-rich biomass and has potential to be an alternative protein source that is more environmentally sustainable than animal and plant derived proteins. A protein-rich powder derived from SoF1 was the test material in a 90-day repeated-dose oral toxicity study to explore major toxic effects, demonstrate target organs, and provide an estimate of a no-observed-adverse-effect level (NOAEL). Daily doses of 0 (vehicle only), 375, 750, and 1500 mg/kg bw/day of the test material were administered by gavage to 10 Han:WIST rats/sex/group. An additional group was administered 1290 mg/kg bw/day whey protein concentrate as positive control. No treatment-related adverse effects were observed, and no target organs were determined after 90/91 days of consecutive administration of the test item. A NOAEL of 1500 mg/kg bw/day was determined.

Iodine identification in major edible seaweed Kappaphycus alvarezii and establishment of an iodine reduction method for its protein extract for utilization as a protein source

Kappaphycus alvarezii is the most widely cultivated seaweed globally. The use of the protein contained in K. alvarezii as an alternative protein source seems to be an effective countermeasure against the protein crisis. Here, we identified the iodine chemical species in K. alvarezii and developed an iodine reduction method. We used various fractionation methods and showed that almost all the iodine in the K. alvarezii alkali extract is present as an iodinated protein, and reducing the amount of iodine per protein was difficult. Subsequently, an iodine reduction method was established to cleave the covalent bonds between the protein and iodine, and we could successfully reduce the amount of iodine per protein by approximately half.

Enhancing Protein Content in Wild-Type Saccharomyces cerevisiae via Random Mutagenesis and Optimized Fermentation Conditions.

Single-cell protein (SCP) derived from microorganisms is widely recognized as a viable alternative protein source for the future. Nevertheless, the commercialization of yeast-based SCP is hampered by its relatively low protein content. Therefore, this study aimed to enhance the protein content of Saccharomyces cerevisiae via random mutagenesis. To achieve this, S. cerevisiae KCCM 51811, which exhibited the highest protein concentration among 20 edible S. cerevisiae strains, was selected as a chassis strain. Subsequently, a KCCM 51811 mutant library was constructed (through UV irradiation) and screened to isolate mutants exhibiting high protein content and/or concentration. Among the 174 mutant strains studied, the #126 mutant exhibited a remarkable 43% and 36% higher protein content and concentration, respectively, compared to the parental strain. Finally, the #126 mutant was cultured in a fed-batch system using molasses and corn-steep liquor, resulting in a protein concentration of 21.6 g/l in 100 h, which was 18% higher than that produced by the parental strain. These findings underscore the potential of our approach for the cost-effective production of food-grade SCP.

Socio-economic and cultural drivers of local perceptions and willingness to consume edible insects in Benin

Insects serve as alternative protein sources for humans. While entomophagy, the practice of eating insects, has deep historical roots in some regions, it remains less common in Benin. Understanding perceptions and determinants of entomophagy can guide actions for promoting the consumption of edible insects. The present study aimed to assess local perceptions of consuming edible insects and the drivers of their adoption. An ethnozoological study using interviews was conducted with 450 individuals from rural and peri‑urban areas in Benin's humid and semi-arid zones. Data were analyzed using descriptive statistics, univariate inference, and classification models. Findings showed greater acceptance of insects’ consumption in the semi-arid zone (33.56 %) than in the humid zone (23.11 %) and in rural areas (33.11 %) than in peri‑urban areas (23.56 %). Edible insects’ consumption was also higher in rural areas (34.22 %) than in peri‑urban areas (27.11 %), with no significant difference between biogeographical zones. Gender, age, and biogeographical zones were key determinants of local perceptions regarding the consumption of edible insects. Furthermore, factors influencing the decision to adopt the consumption of edible insects included perceptions of their nutritional value, gender, duration of residence, and geographical location. These factors can inform awareness raising about the usefulness of edible insects in promoting their consumption.

Development and application of a nutritional quality model for life cycle assessment of protein-rich foods

Alternative protein sources (APSs) have emerged as a potentially healthy and, presumably, environmentally sustainable solution for meeting future food demand. Here we develop a new complex nutrient profile model to assess the nutritional quality of protein-rich foods, which, concurrently, allows to evaluate their environmental implications efficiently through the application of life cycle assessment (LCA). The development of the index was guided by the identification of priority nutrients in APSs and main deficiencies of similar models, which gave rise to the ‘quality Nutrient Rich Food 1.10.2’ (qNRF1.10.2). This model is the first nutrient profile system that combines various essential nutrients and a protein quality scoring system, namely Digestible Indispensable Amino Acid Score (DIAAS). From a nutritional perspective, its accuracy was proven and its application identified animal products as the most nutritionally complete food group, surpassing plant-based alternatives. However, when using the index as functional unit in LCA of protein-rich foods, we discovered that seeds, nuts, and mixtures of vegetable foods reported the lowest environmental impacts as a function of their nutrient density. Some exceptions were found for algae or insects, which performed worse than animal-derived foods in terms of resources consumption, or for cereals, which shown an important water deprivation potential. These results suggest that we should find a trade-off between the production of emerging and conventional foodstuffs, and that main environmental issues of each region should condition the location of production systems.

Comprehensive Analysis of Yoghurt Made with the Addition of Yellow Mealworm Powder (Tenebrio molitor).

The study aimed to be able to incorporate mealworm powder into yoghurts to increase protein content. Tenebrio molitor is gaining popularity as an alternative protein source. In the face of a growing human population and the associated challenges of sustainable nutrition, mealworms offer a promising solution. The mealworm is distinguished by its high protein content and for being rich in essential amino acids, vitamins, and minerals, making it a valuable component of diet. Among others, chemical composition, colour, texture, degree of syneresis, sensory analysis, and microbiological analysis were analysed. As expected, the addition of insect powder increased the protein content from 4.91% (0 TM) to 7.41% (5 TM). It also increased the fat content from 1.67% (0 TM) to 3.88% (5 TM). Furthermore, the addition of mealworm powder resulted in a significant change in the colour of the yoghurt to a darker colour, due to the dark brown colour of the powder. Food with added edible insects is increasingly available but is not always popular due to cultural and psychological barriers. Sensory analysis of yoghurts has shown that the more powder that is added, the less appealing the product becomes and the more bitter the taste.

Caracterización de lenteja y jacinto de agua, efecto en la digestibilidad aparente en la tilapia

Objective. To evaluate the nutritional composition of duckweed (DW) (Lemna minor) and water hyacinth (WH) (Eichhornia crassipes) and its effect on the apparent digestibility of dry matter (%, ADDM), apparent digestibility of crude protein (%, ADCP) and the apparent digestibility of the crude lipid (%, ADCL) in the nutrition of tilapia (Oreochromis niloticus). Material and methods. The DW and WH were used to formulate nine isoproteic (32.47%), isolipidic (5.46%) and isoenergetic (16.45 MJ kg-1) diets, with three replicates and 15 male tilapia (36.36± 1.16 g) per repetition: 0% (T0); 10% (T10); 15% (T15); 20% (T20) and 25% (T25), respectively random. A principal component analysis (PCA) was applied. Results. The crude protein (%) of the WH and the DW, were 21.72% and 27.37% (p˂0.05), respectively. Fish fed with WH and DW, up to 10 and 15% inclusion in the diet, respectively, did not show significant differences (p>0.05) for ADDM. However, for ADCP and ADCL, up to 15 and 20%, respectively, significant differences (p>0.05) were not observed. Conclusions. Water hyacinth and duckweed meals were an alternative vegetable protein source, which can partially replace soybean meal and cornmeal in tilapia diets. The PCA suggests that the control diet, 10% WH, 10-15% DW, showed the best results in terms of the apparent digestibility of the nutrients.

Valorisation of agricultural residues into Thauera sp. Sel9 microbial proteins for aquaculture

Unconventional protein sources are necessary to tackle the increasing demand for food. Microbial proteins (MP) are an alternative source of proteins for feed or food, suitable as feed for aquaculture. Substituting fishmeal with MP obtained from agricultural wastes could reduce the environmental burden of aquaculture and help with waste management. In this study, pure culture MP from the PHA-producer Thauera sp. Sel9 were obtained from agricultural residues (agro-zootechnical digestate and pasta industry leftovers). The produced MP was used in feeding tests with the model fish zebrafish (Danio rerio) to assess potential toxic effects and evaluate overall fish health. The obtained MP was rich in protein (59.5 % w/w over TS) and PHAs (15.0 %) and comprised all fish essential amino acids. The chemical scores and essential amino acid index confirmed the excellent quality of the MP. The feeding tests with 50 % feed substitution with MP resulted in survival rates (80–88 %) comparable to the control group (78 %), with only 100 % MP showing increased mortality. Thauera MP obtained from agricultural residues has the potential to become a partial fishmeal substitute in fish-farming.

Comparison of Cricket Protein Powder and Whey Protein Digestibility.

With the global population projected to reach nine billion by 2050, the search for alternative protein sources has become critical. This study evaluated the digestibility of cricket protein powder compared with that of whey protein powder. Cricket protein powder had a slightly lower protein content but higher fat content than whey protein powder. Although both contained all essential amino acids, their quantities varied. The most abundant essential amino acid was leucine in both samples. The essential amino acid index (EAAI) for cricket protein powder reached 79% when utilising crude protein for calculation. When using the amino acid sum calculation method, it increased by nearly 13%. The EAAI for whey protein was then 94% when calculated based on crude protein, with a slight increase observed when using the amino acid sum calculation method. Cricket protein exhibited a gradual increase in digestibility during intestinal digestion, reaching nearly 80%, whereas whey protein digestibility surpassed 97%. Despite the lower digestibility of cricket protein compared with whey protein, it remains sufficiently high for consideration as a valuable protein source. This study highlights the potential of cricket proteins and underscores the importance of assessing their protein content and digestibility in evaluating their nutritional value.

A comparison of the chemical compositions and nutrient values of the sanim and srithong varieties of the farmed golden apple snails (Gastropoda; Ampullariidae; Pomacea canaliculata)

The comparison of the Sanim (SN) and Srithong (ST) varieties of the farmed apple snail Pomacea canaliculata as an alternative protein source has shown that ST contained more hydroxyproline and possessed a greater firmness than SN. Nevertheless, both varieties yielded similar protein contents of 20.90–23.07 % and exhibited similar texture, color, cooking yields and cooking losses after cooking. Good palatability with high liking score was obtained from both snail meat samples, particularly color, texture, and overall attributes. Snail meats possessed good nutritive value with an amount of protein and low fat content, whereas SN contained higher protein and total energy(P < 0.05). Other nutritionally useful chemicals (such as calcium, sodium, iron, vitamins B1 and B2) are present. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results discovered that myosin heavy chain, paramyosin, and actin were the prevalent protein components. Differences in nitrogen content distribution were observed between SN and ST, in which alkaline-soluble protein was the major fraction. Amino acid composition and fatty acid content varied regarding snail varieties with a large amount of essential amino acids and good source of MUFA and PUFA. Therefore, both farmed SN and ST snails could be an effective alternative protein source with a significant amount of nutritive value.

Protein extracts from microalgae and cyanobacteria biomass. Techno-functional properties and bioactivity: A review

Microalgae and cyanobacteria are photosynthetic and unicellular organisms that contain considerable amounts of proteins, lipids, carbohydrates, and polyunsaturated fatty acids, among others, with applications in the cosmetic, pharmaceutical, and food industries. These microorganisms can accumulate protein up to 70 % of total biomass depending on the microalgal strain, hence they have been regarded as an alternative protein source for the future. Microalgal proteins have important applications such as emulsifying, foaming, and gelation properties, which are important for the determination of quality and texture of foods. Some microalgal peptides possess important bioactivity with many health-benefit effects. Therefore, to maximize the production of proteins from microalgae and cyanobacteria, many protein extraction procedures have been studied to increase the economic return. They have been tested towards higher protein yields at low energy cost, the preservation of protein native properties, and lower cell debris. This later is fundamental to facilitate the subsequent purification processes so that the overall cost can be reduced. The aim of this work is to review some cell disruption processes for the extraction of protein from microalgae and cyanobacteria, considering that this step is crucial for the overall process due to the high rigidness of microalgal cell covering, which can hamper the release of proteins. It also aims at reviewing the purification techniques after cellular disruption, from conventional to more recent approaches, and finally addresses the antioxidant, antidiabetic, antihypertensive, antibacterial and other bioactive properties of microalgal protein hydrolysates and peptides.

Influence of Certain Biostimulants on the Vegetative Growth of Annual Moringa (Moringa oleifera. Lam)

Due to the importance of moringa leaves which can help improve the dietary diversity and quality of households that need to improve their nutritional intake, being a potential alternate source of protein, and for the sake of increasing its growth and yield, this study is determine the effect of some biofertilizers, amino acids and seaweed extract on vegetative growth of moringa seedlings As well as, to find out the best fertilization treatment to improve the vegetative growth of Moringa and reducing the intensive use of chemical fertilizers. This study was conducted in the Experimental Farm of the Faculty of Agriculture (Saba-Basha), Alexandria University, Egypt, during two consecutive seasons of 2020 and 2021, to study the effect of biofertilizers, amino acids, and seaweed extract and its combinations on the growth of Moringa (Moringa oleifera, L.). The experiment was designed as split-split plot design it included 27 treatments with three replicates. The results revealed that the highest significant values of vegetative growth as plant height (171.8 cm), stem length (87.30 cm), stem diameter (3.49 cm), leaves fresh weight (70.61 g), leaves dry weight (13.35g), number of leaves per plant (72.03), and number of leaves per shoot (54.41) were achieved when the trees were soil bio-fertilized and sprayed with the investigated amino acid 700 mg/l + seaweed extract 700 mg/l + cerealine (T26) for both seasons of study. While the number of branches per plant (15.28), shoot fresh weight (138.1g), and shoot dry weight (24.07g) were concerned, the highest values were obtained when the plants were treated with soil bio-fertilization (Phosphorine), sprayed with amino acids, and seaweed extract, as the abovementioned treatments, amino acid 700 mg/l + seaweed extract 700 mg/l + Phosphorine (T25), for both seasons of study compared to the other treatments and control.

Estimating the dynamics of greenhouse gas emission during black soldier fly larvae growth under controlled environmental conditions

Edible insects are considered a sustainable alternative protein source. Several studies have indicated that greenhouse gas (GHG) emissions from insects are generally low. These data were usually recorded in closed static chambers, which did not reflect the actual rearing conditions. On the other hand, open respiration chambers need high amounts of substrate and insects, making the analyses time consuming and expensive. In the present study, a novel small-scale open gas exchange recording system for evaluation of GHG emissions from insects is presented. The device consists of four independent respiration chambers, each one equipped with a pump for supplying air, a flow meter and a septum for sampling the flowing air. A validation experiment was carried out using black soldier fly larvae as model organisms and moistened chicken feed (dry matter 40%) as rearing substrate. Three independent runs were conducted, each with two replicates, using 200 neonates larvae and 300 g of substrate. Moistened chicken feed (300 g) without larvae was used as control. Throughout the 12 days rearing period, gas sampling occurred every 12 h. Data interpolation considering a linear tendency between two successive sampling points was applied and overall amounts of gases were quantified as area under the curve. Irrespective of the run, CO2 emissions in the insect-substrate systems increased during the initial 7 d of experiment, consistently followed by a rapid decrease. Multiple cross correlation analysis showed high reproducibility (r ≥ 0.9), while significant differences in the CO2 emissions between insects-substrate system (range 7.76–11.88 g g−1 dry insects) and sole substrate (range 0.20–0.33 g g−1 initial dry substrate) were observed. Very limited N2O (≤1.13 mg g−1 dry insects) and CH4 (≤1.33 mg g−1 dry insects) emissions were detected in this experiment, indicating that the performed black soldier fly larvae rearing did not result in significant production of these GHGs. Overall, the experiment showed that the novel device may be particularly suited for quick and reliable estimation of GHG emissions from edible insects.

Editorial: Alternative protein source for a sustainable and healthy nutrition

Editorial: Alternative protein source for a sustainable and healthy nutrition

Retention of prions in the polychaete Hediste diversicolor and black soldier fly, Hermetia illucens, larvae after short-term experimental immersion and feeding with brain homogenate from scrapie infected sheep

Finding alternative protein and lipid sources for aquafeeds is crucial for the sustainable growth of fed aquaculture. Upcycling industrial side streams and byproducts using extractive species can reduce waste and help reduce the sector's dependence on fish meal and fish oils. Polychaete worms (Hediste diversicolor) and black soldier fly (Hermetia illucens) larvae (BSFL) are promising candidates for converting waste materials into valuable protein and lipid sources. However, further research and evaluations are needed to ensure the safety and regulatory compliance of these alternative feed sources, especially regarding prions spreading potential in the unlikely case that prions would be introduced in the value chain via feedstocks. In the present investigation, BSFL and juvenile polychaetes that had received a massive dose of scrapie prions through immersion and oral inoculation were found to harbour detectable prions using an ultrasensitive amplification method known as PMCA. This observation suggests that both H. diversicolor and BSFL have the potential to serve as mechanical vectors for prions diseases. However, it is important to note that insects, lacking the prion protein gene, are incapable of propagating prions. Therefore, the quantity of prions present in the larvae will inevitably be lower than the amount of prions they encountered. This is the first study to report on the fate of prions through ingestion by these marine and terrestrial invertebrate species.

Application of Carboxymethyl Cellulose and Glycerol Monostearate as Binder Agents for Protein Powder Production from Honey Bee Brood Using Foam-Mat Drying Technique.

This study investigates the development of protein powder from honey bee drone broods using foam-mat drying, a scalable method suitable for community enterprises, as well as the preservation of bee broods as a food ingredient. Initially, honey bee broods were pre-treated by boiling and steaming, with steamed bee brood (S_BB) showing the highest protein content (44.71 g/100 g dry basis). A factorial design optimized the powder formulation through the foam-mat drying process, incorporating varying concentrations of S_BB, glycerol monostearate (GMS), and carboxymethyl cellulose (CMC). The physicochemical properties of the resulting powder, including yield, color spaces, water activity, solubility, protein content, and total amino acids, were evaluated. The results showed that foam-mat drying produced a stable protein powder. The binders (CMC and GMS) increased the powder's yield and lightness but negatively affected the hue angle (yellow-brown), protein content, and amino acid content. The optimal quantities of the three variables (S_BB, GMS, and CMC) were determined to be 30 g, 6 g, and 1.5 g, or 80%, 16%, and 4%, respectively. Under this formulation, the protein powder exhibited a protein content of 19.89 g/100 g. This research highlights the potential of bee brood protein powder as a sustainable and nutritious alternative protein source, enhancing food diversification and security.

A meta-analysis of the meat physicochemical parameters of broiler chickens fed insect-based diet.

A total of 23 studies were identified in a literature search performed in the Scopus, Science Direct and Google Scholar databases for meta-analysis. The criteria used include studies that were published from 2015 to 2023 and those reporting the effects of insect meal utilisation in poultry diets. Data on live weight (LW), carcass weight (CW), moisture, meat pH, lightness (L*), redness (a*), yellowness (b*), proximate composition (protein, fat and ash content) and shear force in broilers were subjected to OpenMEE software, and data were pooled using a random-effect model. Subgroup analysis and meta-regression were performed to ascertain the influence of dietary insect meals on the response of meat aspects and the source of heterogeneity, respectively, using the following moderators (insect species, dosage level, feeding duration and age at slaughter). The results indicated that dietary insect meal did not affect LW, CW, meat L*, pH, shear force, moisture, fat and ash content. In contrast, dietary insect meal increased the a* of the meat (standardised mean differences (SMDs) = 1.03; 95% confidence intervals (CIs) = 0.484-1.578; p ≤ 0.001), b* (SMD = 1.117; 95% CI = 0.334-1.90; p = 0.005), and meat protein content (SMD = 0.365; 95% CI = 0.031-0.7; p = 0.032). The subgroup analysis showed that insect meal dosage of ≤10% and age at slaughtered ≤35 days had improved the LW, CW and meat L*. In addition, the meat a*, protein and ash content were also influenced by insect species, dosage levels and age at slaughter. In conclusion, ≤10% of either Hermetia illucens or Tenebrio molitor can be included in broiler diets without compromising the LW, CW, meat pH, colour, shear force, moisture, fat and ash content in broilers. The study therefore indicated that insect meals have a bright future as an alternative protein source in poultry diets.