Life Cycle Environmental Impacts and Health Effects of Protein-Rich Food as Meat Alternatives: A Review

Production of high protein yeast using enzymatically liquefied almond hulls

Animal feed ingredients, especially those abundant in high quality protein, are the most expensive component of livestock production. Sustainable alternative feedstocks may be sourced from abundant, low value agricultural byproducts. California almond production generates nearly 3 Mtons of biomass per year with about 50% in the form of hulls. Almond hulls are a low-value byproduct currently used primarily for animal feed for dairy cattle. However, the protein and essential amino acid content are low, at ~30% d.b.. The purpose of this study was to improve the protein content and quality using yeast. To achieve this, the almond hulls were liquefied to liberate soluble and structural sugars. A multi-phase screening approach was used to identify yeasts that can consume a large proportion of the sugars in almond hulls while accumulating high concentrations of amino acids essential for livestock feed. Compositional analysis showed that almond hulls are rich in polygalacturonic acid (pectin) and soluble sucrose. A pectinase-assisted process was optimized to liquefy and release soluble sugars from almond hulls. The resulting almond hull slurry containing solubilized sugars was subsequently used to grow high-protein yeasts that could consume nutrients in almond hulls while accumulating high concentrations of high-quality protein rich in essential amino acids needed for livestock feed, yielding a process that would produce 72 mg protein/g almond hull. Further work is needed to achieve conversion of galacturonic acid to yeast cell biomass.

Plant-Based Diets Are Not Enough? Understanding the Consumption of Plant-Based Meat Alternatives Along Ultra-processed Foods in Different Dietary Patterns in Germany

A low-processive plant-based diet is considered valuable for a sustainable diet profile-it is supposed to meet health as well as environmental concerns. However, there is a growing trend toward plant-based meat alternatives, most of which are to be classified as ultra-processed food (UPF). The paper aimed to understand the consumption of different ultra-processed foods to describe their relation to dietary patterns and sustainability. The objective was (1) to depict the status-quo of consumption of plant-based meat alternatives along with other UPF groups (i.e., convenience products, fast foods, snacks, ultra-processed beverages) in a German sample (n = 814) and (2) to investigate the extent to which all examined UPFs are represented in different dietary patterns (vegetarian, flexitarian, regular meat-eaters, high meat-eaters). UPF intake and dietary groups were determined using a food frequency questionnaire (FFQ). Potential factors influencing UPF consumption, such as attitudes toward sustainability and healthy eating practices, were assessed using validated and fitted psychometric scales. Overall, the frequency of UPF consumption varies significantly along the product groups studied. Plant-based meat alternatives were the least consumed food (12.3%), followed by convenience products (57.4%), fast foods (55.9%), ultra-processed beverages (80.1%), and sweet and salty snacks (97.3%). Plant-based meat alternative consumption predominated within a vegetarian diet, while other UPFs, like convenience products, fast foods, sweet and salty snacks, and ultra-processed beverages, were mainly consumed by meat-eaters. Remarkably, flexitarian diets depict low consumption of all types of ultra-processed foods. In order to meet societal sustainability goals, diets and corresponding societal and political actions should emphasize not only plant orientation but also the increase of non- and low-processed foods.