Nitrogen/protein and one-step moisture and ash examination in foodstuffs: Validation case analysis using automated combustion and thermogravimetry determination under ISO/IEC 17025 guidelines.

Method validation within food science is a not only paramount to assess method certainty and ensure the quality of the results, but a pennant in analytical chemistry. Proximate analysis is an indispensable requirement for food characterization. To improve proximate analysis, automated protein and thermogravimetric methods were validated according to international guidelines (including ISO 17025) and acceptance criteria of results based on certified reference materials and participation within international recognized proficiency schemes. Common food groups (e.g., meat, dairy, and grain products) were included and at the end of validation, we obtained three rugged and accurate methods with adequate z scores (-2 ≥ x ≤ 2) and recoveries (92-105%). During optimization, variables such as gas flows, subsample masses, and temperatures were varied and specific conditions (those that rendered the best results) were selected for each food group. For each validated method, a comparison (technical and economic) among the data obtained and the data extracted for its traditional counterpart were included: assays validated demonstrate to be more cost-effective labor-wise (ca. 9 and 16-fold) than their traditional alternatives. Specifically for combustion assay regression analysis (y = 0.9361x, y = 1.1001x, and y = 0.9739x, for meat, dairy and grain products, respectively) were performed to assess the factor, if any, which must be applied to the results to effectively match those obtained for Kjeldahl method. Finally, in the case of protein, samples can be analyzed under 5 min with no residue and a subsample mass below 400 mg. Moisture and ash analysis can be performed simultaneously using the same subsample. Data herein will also help harmonize and advance food analysis toward more efficient greener methods for proximate analysis.

Selected Instrumental Techniques Applied in Food and Feed: Quality, Safety and Adulteration Analysis.

This review presents an overall glance at selected instrumental analytical techniques and methods used in food analysis, focusing on their primary food science research applications. The methods described represent approaches that have already been developed or are currently being implemented in our laboratories. Some techniques are widespread and well known and hence we will focus only in very specific examples, whilst the relatively less common techniques applied in food science are covered in a wider fashion. We made a particular emphasis on the works published on this topic in the last five years. When appropriate, we referred the reader to specialized reports highlighting each technique's principle and focused on said technologies' applications in the food analysis field. Each example forwarded will consider the advantages and limitations of the application. Certain study cases will typify that several of the techniques mentioned are used simultaneously to resolve an issue, support novel data, or gather further information from the food sample.

Total and resistant starch from foodstuff for animal and human consumption in Costa Rica.

Starchy ingredients are a key source of carbohydrates and have an essential role in a healthy diet. Starch amount in foodstuffs is paramount as it allows diet professionals to base their formulations on scientific data. Herein, the total (TS) and resistant starch (RS) content, in a selection of typical starchy foods available on the Costa Rican market, for both human and animal consumption, is reported. The major types of starch, including physically encapsulated starch, were determined using in vitro methods AOAC OMASM methods 996.11, 2014.10, 996.11, 2002.02 and AACC 76-13.01 and 32-40.01. Samples were collected during 5 years as part of national surveillance plans. For feedstuffs, n = 252 feed ingredients (e.g., cornmeal and wheat products), n = 103 feeds (e.g., dairy and beef cattle), and n = 150 feed ingredient samples (selected based on their usage in feed formulations) were assessed for RS. In food commodities, sample numbers ascended to n = 287 and n = 371 for TS and RS, respectively (e.g. bananas). Feed ingredients with higher TS values were cassava meal, bakery by-products, rice/broken, sweet potato, and cornmeal (93.37, 81.67, 72.33, 66.66, and 61.43 g/100 g, respectively). TS for beef and dairy cattle, pig, and calf feeds, ranged from 30.26 to 34.46 g/100 g. Plantain/green banana flour, as a feed ingredient, exhibited RS absolute and relative contributions of 37.04 g/100 g and 53.89%, respectively. Products with a higher TS content included banana flour, green plantain flour, japonica rice, and cassava flour (62.87, 63.10, 72.90, 83.37 g/100 g). The primary RS sources in the Costa Rican diet are, in absolute terms, green plantain and malanga (50.41 and 56.59 g/100 g). Depending on a person's food habits, these sources may contribute in the range of 20-30 grams of RS per day. TS and RS intake may vary considerably among ingredients, and the contribution of RS may be of nutritional importance for specific individuals.

Simultaneous LC/MS Analysis of Carotenoids and Fat-Soluble Vitamins in Costa Rican Avocados (Persea americana Mill.).

Avocado (a fruit that represents a billion-dollar industry) has become a relevant crop in global trade. The benefits of eating avocados have also been thoroughly described as they contain important nutrients needed to ensure biological functions. For example, avocados contain considerable amounts of vitamins and other phytonutrients, such as carotenoids (e.g., ß-carotene), which are fat-soluble. Hence, there is a need to assess accurately these types of compounds. Herein we describe a method that chromatographically separates commercial standard solutions containing both fat-soluble vitamins (vitamin A acetate and palmitate, Vitamin D2 and D3, vitamin K1, α-, δ-, and γ-vitamin E isomers) and carotenoids (ß-cryptoxanthin, zeaxanthin, lutein, ß-carotene, and lycopene) effectively (i.e., analytical recoveries ranging from 80.43% to 117.02%, for vitamins, and from 43.80% to 108.63%). We optimized saponification conditions and settled at 80 °C using 1 mmol KOH L-1 ethanol during 1 h. We used a non-aqueous gradient that included methanol and methyl tert-butyl ether (starting at an 80:20 ratio) and a C30 chromatographic column to achieve analyte separation (in less than 40 min) and applied this method to avocado, a fruit that characteristically contains both types of compounds. We obtained a method with good linearity at the mid to low range of the mg L-1 (determination coefficients 0.9006-0.9964). To determine both types of compounds in avocado, we developed and validated for the simultaneous analysis of carotenoids and fat-soluble vitamins based on liquid chromatography and single quadrupole mass detection (LC/MS). From actual avocado samples, we found relevant concentrations for cholecalciferol (ranging from 103.5 to 119.5), δ-tocopherol (ranging from 6.16 to 42.48), and lutein (ranging from 6.41 to 15.13 mg/100 g dry weight basis). Simmonds cultivar demonstrated the higher values for all analytes (ranging from 0.03 (zeaxanthin) to 119.5 (cholecalciferol) mg/100 g dry weight basis).

Pet Food Quality Assurance and Safety and Quality Assurance Survey within the Costa Rican Pet Food Industry.

Costa Rican animal feed production is continually growing, with approximately 1,238,243 metric tons produced in 2018. Production-wise, pet cat and dog food are in fifth place (about 41,635 metric tons per year) amongst animal feeds, and it supplies up to 90% of the national market. Pet food production has increased as a response to the increase in the population of dogs and cats in Costa Rica, where 50.5% of households own at least one dog and indicates more responsible ownership in terms of feeding pets. Part of the process of making dry pet food involves a thermal process called extrusion, which is capable of eliminating the microbial load. However, extrusion can compromise nutritional quality to some extent by denaturing proteins, oxidizing lipids, and reducing digestibility. The objective of this study was to evaluate the quality and safety of dry pet food and to assess the effect of the extrusion process on digestibility and the quality of proteins, amino acids, and fatty acids. Pet food samples were collected before and after extrusion and were used to evaluate Good Manufacturing Practices (GMP), based on Central American Technical Regulation (RTCA 65.05.63:11). In general terms, weaknesses in infrastructure, documentary evidence, and post-process practices were observed in two Costa Rican feed manufactories. Feed safety was surveyed through the analysis of Salmonella spp., Escherichia coli, Listeria spp., Staphylococcus aureus, aerobic mesophilic microorganisms, fungi, and yeasts counts. The extrusion process effectively reduced pathogenic microorganisms, and showed no effect on the digestibility of dog food (p = 0.347), however, it could reduce the availability of some nutrients (e.g., amino acids, fatty acids). Furthermore, a retrospective diagnosis was made for puppy food (n = 68), dog food (n = 158), and cat food (n = 25), to evaluate the history of nutritional quality and safety. Finally, it can be confirmed that the correct implementation of GMP allows feed manufacturers to deliver a product of optimum texture, smell, nutritional composition, and safety.

Liquid Chromatography Analysis of Common Nutritional Components, in Feed and Food.

Food and feed laboratories share several similarities when facing the implementation of liquid-chromatographic analysis. Using the experience acquired over the years, through application chemistry in food and feed research, selected analytes of relevance for both areas were discussed. This review focused on the common obstacles and peculiarities that each analyte offers (during the sample treatment or the chromatographic separation) throughout the implementation of said methods. A brief description of the techniques which we considered to be more pertinent, commonly used to assay such analytes is provided, including approaches using commonly available detectors (especially in starter labs) as well as mass detection. This manuscript consists of three sections: feed analysis (as the start of the food chain); food destined for human consumption determinations (the end of the food chain); and finally, assays shared by either matrices or laboratories. Analytes discussed consist of both those considered undesirable substances, contaminants, additives, and those related to nutritional quality. Our review is comprised of the examination of polyphenols, capsaicinoids, theobromine and caffeine, cholesterol, mycotoxins, antibiotics, amino acids, triphenylmethane dyes, nitrates/nitrites, ethanol soluble carbohydrates/sugars, organic acids, carotenoids, hydro and liposoluble vitamins. All analytes are currently assayed in our laboratories.

Two alternative chromatography methods assisted by the sulfonic acid moeity for the determination of furosine in milk.

N6-(2-(2-Furanyl-2-oxoethyl))-l-lysine (furosine) is a deteriorative reaction product that is produced during heat treatment and storage of milk. This compound affects the quality of commercial dairy products. Accurate determination of furosine is necessary as it may serve as a measure of the degree of protein degradation in dairy products. In this article, two HPLC based methods (1. a novel ion-pairing reagent 2. a strong cation exchange column) are proposed to quantify furosine. These methods were optimized and validated for their application to analyze fluid milk and dried milk powder. •Two methods that can be used for routine milk quality control, including heat damage and adulteration, were developed.•Compared to previous methods, the modified procedures herein using aromatic sulfonic acids (a pairing agent or covalently bound to a matrix on a strong cation exchange column) provide less expensive and more sensitive determinations.•The identification and quantification of the furosine chromatographic signal was successfully achieved during analysis of commercial and spiked samples.

A straightforward LC approach using an amine column and single quad mass detector to determine choline chloride in feed additives and feeds.

Considering choline (ChCl) as an essential ingredient for animals and that it is administered through feed, we developed an easy, accurate, and sensitive method for its analysis. The method is straightforward, derivatization-free and has no secondary chromatographic interactions. •We demonstrated that the method can be used for quality control for feeds and feed additives containing choline chloride•We report a simple chromatographic method which takes advantage of the hydroxyl moiety present in ChCl and a MS detector.•We demonstrated that a single quadrupole detector is an effective option for the quantification of ChCl in feeds as an alternative for the more expensive tandem MS system.

Use of the adamantane structure in medicinal chemistry.

This review summarizes the importance and recent discoveries of the use of adamantane derivatives in Medicinal Chemistry. We have organized the article in 4 sections: 1) Absorption, Distribution, Metabolism, or Excretion (ADME) properties 2) Hydrophobic Effects 3) Ion Channels and 4) Rigid scaffold. Within each section, we have provided examples of how the adamantane group changes the properties of known drugs or provides a important pharmacophore for the design of new drugs.