nx_preservation.nx

nx_preservation.nx -- FOOD-SCIENCE SUITE / PRESERVATION rung. The classic food-preservation science the ferment ladder didn't yet cover: thermal death kinetics (D-value / z-value / the 12-D botulinum cook), water activity (aw), and Leistner HURDLE technology -- with a never-poison canning gate. All INTEGER-EXACT (no float, no precision cliff): decimal reduction and z-value scaling are powers of ten (exact), water-activity + pH control are threshold rules (exact). Quantities in milli-units: time -> milli-minutes (mmin) temp -> milli-Celsius (mC) aw, pH -> x1000 (aw 0.850 = 850; pH 4.600 = 4600) log-reductions -> milli-reductions (12 log = 12000) THE never-poison line (mirrors nx_ferment_safety, Global Rule 26): a LOW-ACID food (pH >= 4.6, where C. botulinum can grow) may NEVER be preserved by boiling-water-bath canning -- it MUST be pressure-canned to achieve the 12-D botulinum cook. Structural refusal, liar-killed by the gate (the #1 cause of home-canning botulism). THE measured exceed: a single-factor checker calls a food unsafe unless pH<4.6 OR aw<0.85 alone. The HURDLE model correctly finds foods that are stable because pH AND aw are BOTH moderately reduced together (Leistner) -- how shelf-stable fermented sausage, aged cheese, and many intermediate-moisture foods actually work. Grounding (cited; researcher-groundable like nx_probiome): fda_21cfr113_114_low_acid_acidified_canning (pH 4.6 line) c_botulinum_12D_D121_0.21min_z_10C (thermal death) nchfp_pressure_vs_boiling_water_canning (method rule) fda_water_activity_0.85_not_potentially_hazardous (aw pathogen floor) leistner_hurdle_technology_combined_preservation (hurdle exceed) genealogy_id: nishi_ferment_safety_r0_never_poison + food_preservation_science